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Sam Murray, June 2017 eBirder of the Month

Mon, 07/17/2017 - 15:18

Sam Murray, June eBirder of the Month

17 July 2017

Sam birding in coastal Georgia
Please join us in congratulating Sam Murray of Augusta, GA, winner of the June 2017 eBird Challenge, sponsored by Carl Zeiss Sports Optics. Our June winner was drawn from eBirders who submitted 15 or more eligible checklists containing at least one breeding code in June. Sam’s name was drawn randomly from the 1,769 eligible eBirders who achieved the June challenge threshold. Sam will receive new ZEISS Conquest HD 8×42 binoculars for his eBirding efforts. Read more to see Sam’s full story.

When I started birding in November 2012, I was immediately hooked on the competitive side of birding. I loved making lists, seeing how many species I could rack up and find in a limited time period. When I was introduced to eBird a few months later, my addiction for birding only increased! I was determined to rise up the ranks of the Top 100 in my region, and I was simply amazed by the analysis tools the site had to offer.

I just returned from a 3 week road trip in Arizona with 2 fellow birders. It was the best 3 weeks of my life, and we couldn’t have had the luck we had without eBird. Over these three weeks we racked up 255 species total, with 109 of them being lifers for myself. Being from Georgia, the Western species were new game for me. I’m sure many will agree with me when I say that Southeast Arizona could be mistaken for another planet. Everything, from the bugs, to the landscape, to the stars seems different out there. Picking up Black-throated Gray Warblers along the Grand Canyon, and getting cut up by Junipers while chasing Black-capped Vireos in Texas, are memories I will never forget. Our best birds included Montezuma Quail, Flame-colored Tanager, and Common Crane. Some of my favorites were Elegant Trogon, Buff-breasted Flycatcher, Red-faced Warbler, and Mexican Whip-poor-will. Without eBird, we would not have been able to find a large amount of the species we saw.

Montezuma Quail from the recent Arizona trip. Photo by Sam Murray/Macaulay Library.

It’s also a great feeling submitting checklists, knowing you’re benefitting research for these species, while picking up lifers at the same time! I think eBird is the best thing to happen to birding in a long time, and I hope everyone is using it someday.

eBird’s New Illustrated Checklists: Digital Bird Guides for Any Region in the World

Fri, 07/14/2017 - 08:47

eBird Illustrated Checklists are here!

14 July 2017

Want to work on your tricky IDs? Use an Illustrated Checklist to see and hear all the possible species at a place! Henslow’s Sparrow by Ian Davies/Macaulay Library
You can now view a digital bird guide for any hotspot or region in the world: an Illustrated Checklist. The best part? It’s all using sightings that you contributed! We take the highest-rated photo and sound from the Macaulay Library, combine with eBird data to show seasonal occurrence, and include the last date when a species was seen in that place. The result: a quick overview for the region that gives the most relevant information. Want your photo to be the best image for that region? Add them to your eBird checklists! To check out Illustrated Checklists, search for any region or search for any hotspot. At the top of the species list you’ll see a new tab titled “Illustrated Checklist”. Here’s an example.

This functionality is another great example of the close connection between eBird and the Macaulay Library at the Cornell Lab of Ornithology. We hope these Illustrated Checklists provide an exciting new way to visualize the contributions you’ve made to eBird and ML, an added incentive to add your top photos from your favorite spots, and a window through which you can explore the contributions of others. Have fun, and don’t forget to add star ratings for your images! Now we’re going to get back to uploading our photos to our favorite patches…

Looking for sounds and photos of the birds you might see on your next trip? Illustrated Checklists have everything you need to get prepared.

Eight Great Reasons to Love the Migratory Bird Stamp

Wed, 07/12/2017 - 09:04
The 2017-2018 stamp features a trio of Canada Geese and was painted by James Hautman.Jennifer Miller's gorgeous painting of a pair of Ruddy Ducks is on the 2015-2016 stamp.The 2013 stamp featured a Common Goldeneye and was painted by Robert Steiner, who also won the contest in 1998-1999 with a picture of a Barrow's Goldeneye.Robert Steiner's 1998 stamp of a Barrow's Goldeneye, raised nearly $25 million for refuges in a single year.The very first duck stamp sold for $1 in 1934 and was designed by "Ding" Darling (who now has a refuge named for him).The 1950-51 stamp (Trumpeter Swans by Walter A. Weber) was the first to be chosen by competition.Sherrie Russell Meline won the 2005 contest with her Ross's Goose, becoming only the second woman to have won so far.In 1960, this Redheads stamp by John A. Ruthven was the first to top $5 million in sales.Black-bellied Whistling-Ducks by James Hautman (1990). In the movie "Fargo," a character named Hautman is a strong Duck Stamp contender.These Cinnamon Teal from 1971 remain the highest-selling stamp with almost 2.5 million sold. By Maynard Reece.For more on the history and future of the stamp, join the Friends of the Migratory Bird/Duck Stamp (see link below).PreviousNext

Tip: You can buy the 2017-2018 stamp at many post offices, National Wildlife Refuge offices, and sporting-goods stores, as well as online from USPS and Amplex.

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A brand-new piece of fine art went on sale this summer, and at just $25 it’s a bargain. Its official name is the 2017–2018 Migratory Bird Hunting and Conservation Stamp, but many people know it as the Federal Duck Stamp. Here at the Cornell Lab, we call it the Migratory Bird Stamp because it benefits many kinds of birds and is a great idea for any bird watcher or conservationist.

Buying a Migratory Bird Stamp is a simple and direct way for people to contribute to grassland and wetland conservation. In 2013, the New York Times ran a piece on the annual stamp art competition; now here’s our own list of eight reasons to love the stamp:

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1. Over $900 million for conservation and counting. The first stamp was issued in 1934. It cost $1 (about $18 in today’s dollars) and sold 635,001 copies. By law, the funds raised go directly to habitat acquisition in the lower 48 states. By now, stamp sales have surpassed $900 million and helped to protect 6.5 million acres of wetland and grassland habitat.

2. A 79-year tradition of beautiful wildlife art. The Migratory Bird Stamp is a beautiful collectible and a great artistic tradition. Since 1949, the design of each year’s duck stamp has been chosen in an open art contest. The 2015 stamp, showing a pair of Ruddy Ducks, is by Jennifer Miller (see a gallery of all stamps back to 1934), who is only the third woman to win the contest.

3. A bargain at $25. Ninety-eight cents of each dollar spent on a stamp goes directly to land acquisition (and immediate related expenses) for the National Wildlife Refuge System. This $25 purchase is perhaps the single simplest thing you can do to support a legacy of wetland and grassland conservation for birds.

4. It’s much more than ducks. Waterfowl hunters have long been the main supporters for the program—the stamps are a requirement for anyone over 16 who wants to hunt. But the funds benefit scores of other bird species, including shorebirds, herons, raptors, and songbirds, not to mention reptiles, amphibians, fish, butterflies, native plants, and more.

5. Save wetlands; save grasslands. Since 1958, the U.S. Fish and Wildlife Service has used stamp revenues to protect “waterfowl production areas”—over 3 million acres—within the critical Prairie Pothole Region. The same program also protects declining prairie-nesting birds in the face of increasing loss of grasslands. As a result, refuges are among the best places to find grassland specialties such as Bobolinks, Grasshopper Sparrows, Clay-colored Sparrows, Sedge Wrens, and others.

6. The benefits are gorgeous. Some of the most diverse and wildlife-rich refuges across the Lower 48 have been acquired with stamp funds. Check out this map—chances are there’s a wildlife refuge near you that has benefited:

7. It’s your free pass to refuges. A migratory bird stamp is a free pass for an entire year to all refuges that charge for admission—so your $25 could even save you money.

8. As bird watchers, let’s get in on the secret. Though it’s long been a fixture in hunting circles, the Migratory Bird Hunting and Conservation Stamp is one of the best-kept secrets in all of bird conservation. It’s time to buy and show your stamp!

The Cornell Lab is a strong supporter of the Migratory Bird Stamp, and we’ve often written about its value as a direct aid to conservation—for example, in this 2009 column by Lab director John Fitzpatrick. You can buy the stamp at many U.S. Post Offices, National Wildlife Refuges, and sporting-goods stores. You can also order the stamp online at the USPS store and from the stamp’s printer, Amplex (both stores add a charge for shipping).

(Thanks to the Friends of the Migratory Bird/Duck Stamp for help in preparing this post.)

Gaining Control of Invasive Plants

Mon, 07/10/2017 - 14:01

Gaining Control of Invasive Plants
Jacob Johnston July 10, 2017
00–0
In a flash, invasive plants can alter plant communities in the natural areas, backyards, and other green spaces around us, leaving us feeling a bit helpless and overwhelmed at the sheer scale of their transformative power. Resistance may seem futile, but management is possible. The impressive picture above shows Japanese knotweed’s eye-popping efficiency as a nonnative invader. Aggressive species like this come equipped with a suite of growth and reproduction advantages aimed at efficient colonization; but, when they are non-native, they lack the common predators, diseases, and other natural forces of their native range that usually control or limit their spread. This can advantage them over native plants that are now under greater competition for the same resources. With the right approach, you can become the predator or pathogen that keeps invasive plants from assimilating your landscape.

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Invasive plant species may come from all over the planet but can typically be separated into a limited number of categories based on growth habits. Asking questions about the plant species you are dealing with, whether it is an annual or perennial, has fibrous or tap roots, woody or herbaceous stems, and knowing what the seasonal timing of growth and reproductive events are will reveal important things to consider when developing a plan for management. Knowing the categories an invasive plant falls into also lets you know which specific approaches to management are likely to work. Here, we help you to understand these characteristics and how to target your efforts at key phases of their life cycles to put the pressure on and gain some control of the processes that create invasions.

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Practices for controlling invasive species vary in scale and size and cover a range of costs and benefits. Some methods of habitat management are handled by trained and certified professionals, like the seasonal controlled or prescribed burn of Reed Canary grass demonstrated above, but most methods are accessible to the general gardener or land manager.

LEAF interns remove invasive species—Asiatic Bittersweet and Black Swallow-wart—from TNC’s Lewis Farm on Block Island in Rhode Island. These invasives threaten the native Milkweed plant, a treat and stopover point for monarch butterflies during thei
Mechanical control methods are the most common and include actions like mowing, pruning, and pulling. These can be labor intensive but are, generally, inexpensive. Chemical control methods are less laborious and can be highly effective but are more costly and have other risks associated with them. We’ll discuss some ecological tips to reduce the labor, costs, and risks for the methods you choose.

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Biological control, although rare, is another effective method implemented in large-scale cases of nonnative plant invasion. This method uses biological elements like insect predators, fungus, parasites, or other pathogens of the plant from its native range to control the population. A popular example of a biological control is use of beetle and weevil species that eat parts of purple loosestrife (latin name) whose overpopulation in North American wetlands dramatically influences the local ecology where it growsopen_in_new. The image above shows one of the 4 species of insects that are used in the biocontrol–two beetles that eat leaves, a weevil that eats blossoms, and another weevil that lives in the soil and eats at the roots.

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Years of extensive research and trials are required to obtain a successful biocontrol that is safe to release into the environment. The insects, like those selected to treat purple loosestrife, need to be capable of reproducing and maintaining a viable population but not pose a threat–like eating non-target plants–to the environment where they are released. Although successful in many parts of the country, the local results of this biocontrol, along with many invasive species controls, depend a lot on the conditions and surrounding influences of the site, and the restoration effort or management afterward.

TNC Kentucky staff look at preserve plans at Dupree Nature Preserve.
Start with a Plan
Before digging in, it is important to determine the overall achievable goal given the size of the area and the degree of the invasion. A goal of complete eradication may only be possible in a small area with minimal invasion. As elimination is not usually practical, control of the existing population is the next desirable outcome. Control requires active measures to remove a large proportion of the invasive population, replant native plant selections, and then maintain negative pressure on the reproduction processes of the remaining invasive species to restore a balance to the resource competition in the area, creating a diversity of plants, habitats, and ecosystem services.

Conservancy staff and volunteers hike up to Cascade Head Preserve in Otis, Oregon to remove invasive Himalayan blackberry bushes.
If the area is too large for the available effort, alternate options for the overall goal of management include containment and mitigation. In vast areas with heavy invasion, sometimes containment may be the the best option, depending on the available resources, to prevent further spread into neighboring areas. For example, a nearby infested area, with more work than possible, may threaten to encroaching on a pristine area and it is easier to remove the few that come to the area or leave the containment area. This requires the smaller task of monitoring and taking steps to remove any new or existing occurrences outside of the designated containment area. Above, the few invasive Himalayan blackberry bushes attempting to spread beyond the contained area are easily being removed. Mitigation may allow the continued spread of the invasive but will attempt to offset some of the damaging effects of the invasion through active measures.

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To decide the amount of effort and the overall goal of the management, divide the area into sections that require different types of control. Investigate the best control for each type of invasive species within those areas. You may have invasive shrubs in the hedgerow that require mechanical removal, a ground cover that is taking over the gardens, and garlic mustard filling the understory of the back woods. These all require different control measures with different timeframes and various goals for the outcome. Your plan should out line these actions and their timeframes.

 

As managers and stewards of the land, we have the opportunity (and the responsibility!) to be the control factor that puts growth limits on invasive species. With the right knowledge and the correct tools, we can be efficient and effective forces on nonnative plants in ways that limit their reproduction, their influence, and their inevitable spread. Regional, large scale eradication has not usually been possibleopen_in_new but maintaining native plant diversity in select areas, like backyards or local parks, can certainly be achieved.

Previous Article: Why Are Invasive Plants Invasive?

NEXT ARTICLE: Control Measures for Invasive Plants
(Coming Soon!)

Minimize Ticks in Your Outdoor Spaces with These Tips from Habitat Network

Thu, 07/06/2017 - 13:28

Creating beautiful landscapes at home and in our community that support a diversity of wildlife while also minimizing our exposure to ticks requires us to understand tick ecology and design our spaces appropriately.

The post Managing Yards and Green Spaces to Minimize Tick Populations appeared first on Habitat Network.

What Makes a Tick, Tick? The Ecological Needs and Life Cycle of the Blacklegged Tick

Thu, 07/06/2017 - 13:27

What Makes a Tick, Tick? The Ecological Needs and Life Cycle of the Blacklegged Tick
Becca Rodomsky-Bish July 6, 2017
Healthy Ecosystems Other Wildlife
00–0
Ticks are ecologically complex Arachnids. Researchers are continuously discovering new dimensions to the elaborate interplay between ticks, their ecosystems, and human health. Understanding what makes ticks, tick may help individuals and communities make management decisions to minimize tick populations. In this article we’ll set the stage for these recommendations by elaborating on the life of a tick. Then, in a sister article we provide land management recommendations based on current understandings of tick ecology.

tick range
Media attention has focused on the blacklegged tick (Ixodes scapularis) and western blacklegged tick (Ixodes pacificus) because these species transmit the Lyme disease-causing bacterium, Borrelia borgdorferi . Lyme is a growing human health concern with over 300,000 reported cases per year.open_in_new The blacklegged tick (Ixodes scapularis) is found throughout the northeast, southeast, and in portions of the midwest. The western blacklegged tick (Ixodes pacificus) is found predominantly in California, Oregon, Washington, and parts of New Mexico, Arizona, and Utah. While all ticks are capable of carrying pathogens that can cause disease, not all ticks that bite are carriers of pathogens or can transfer disease. To learn more about the diversity of ticks and the diseases they carry, visit the Center for Disease Control and Prevention. For purposes of this article we will focus on the blacklegged ticks.

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Blacklegged ticks are native to the United States. They are not an introduced invasive species. Changing environmental conditions, however, may be affecting the percentage of ticks harboring the Lyme disease-causing bacterium (B. burgdorferi) and increasing in their populations by enabling the expansion of tick ranges.open_in_new
These conditions include, but are not limited to:

Warmer, wetter, and more humid conditions within blacklegged tick ranges.open_in_new
Growing populations of preferred blood meal hosts White-footed mice and white-tailed deer (Hosts are organisms that parasites like ticks depend on to acquire nourishment and shelter).
Habitat fragmentation.open_in_new
Decreased biodiversity in native habitat.open_in_new
Fewer predators of mice and deer, which are the primary hosts responsible for transmission of B. burgdorferi in natural ecosystems.open_in_new
We will examine each of these conditions as they relate to the complex ecological needs and life cycle of ticks.

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Ticks have long life cycles. Adult female ticks generally feed on a mammalian host and mate in the fall before overwintering in the leaf litter or soil (see image below, the engorged female in the bottom of the image just laid the shiny yellow eggs). In spring the females lay a batch of eggs (on average an egg mass is approximately 3000 eggs), which hatch into larvae in the summer (larva is depicted as the small tick to the right, above the egg mass). These larvae seek a blood meal, drop off the host, and then molt into the nymphal stage (nymph is center, above the egg mass, looks like a small adult tick). The nymphs then become inactive and overwinter in the leaf litter or soil.

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The next spring, nymphs emerge and seek a blood meal. In early summer they molt into an adult (the female is the largest tick to the left, male is the darker, smaller large tick to the right) and go in search of a blood meal and mate in preparation for laying eggs the next spring.open_in_new

There can be some variation to this cycle depending on weather and availability of hosts. Under pressure, ticks can remain in larval, nymphal, and adult developmental stages for longer periods of time.open_in_new On average, however, their life cycle spans two years, but can span up to four years for the blacklegged tick (I. scapularis) and three years for the western blacklegged tick (I. pacificus)open_in_new

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The length of a ticks’ life cycle is one of the greatest challenges in efforts to study and minimize tick populations. As ecologist Solny A. Adalsteinsson articulates, ticks have long lags in their developmental phasesopen_in_new and climatic or environmental pressures that may minimize the density of ticks at one developmental stage may not impact ticks at other developmental stages. For instance, heavy rainfall may flood forests in the spring and summer while nymphs are questing for blood meals. This flooding, however, may not affect ticks at other developmental stages. A set back one year, at one developmental level, is not likely to have a major long-term impact in overall populations of ticks.

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Blacklegged ticks require a somewhat particular set of environmental conditions to survive. Like Goldilocks, they need environments that are not too wet and not too dry, not too hot or too cold, and with weather that is relatively stable.open_in_new

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Ticks have some tolerance to cold temperatures. In laboratory studies conducted on fed vs. unfed larvae and nymphs there is between 50-100% mortality of the blacklegged tick (I. scapularis) exposed to eight hours or more of temperatures in the -10°C (14°F) to -17°C (1.4°F).open_in_new Those with blood meals in their system, can tolerate colder temperatures for longer periods of time.

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In native habitat, ticks may be more hardy in colder temperatures depending on the depth of leaf litter or availability of insulating snow.open_in_new This may be one reason for a slower expansion of ticks in the higher altitudes and northern latitudes of their natural ranges.open_in_new Some research points to the abundance of tick predators in ecosystems as being more significant than snow pack or cold temperatures, such as this Lycosidae family of wolf spiders pictured above.open_in_new

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In temperatures 32°C (89.6°F) and above ticks exhibit a reduced ability to lay eggs, less questing (searching for host to attach to for bloodmeal), and some mortality.open_in_new Temperatures above 40°C (104°F) result in significant tick mortality.open_in_new Heat equals desiccation (dryness). Heat, especially in the absence of humidity, can be a killer of ticks.

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Moisture and humidity are ticks’ best friends. As small, hard-bodied animals, they rely on their environment to maintain adequate hydration. In a tick’s long life cycle, they will only feed up to three times–spending the rest of the time trying to stay alive between moltsopen_in_new by hiding in the thick, moist, leaf litter to avoid desiccation. This is why most ticks, in all stages of their life cycle, favor forested or semi-forested conditions where there is substantial leaf litter and soil organic matter.open_in_new

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In research comparing tick densities in deciduous vs. coniferous forests, tick nymph’s populations were greater in deciduous forests. This bias is speculated to be correlated with the movement of bloodmeal hosts, specifically white-tailed deer (Odocoileus virginianus) who prefer feeding in the rich understory of deciduous forests.open_in_new

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Blood meals are essential for ticks to survive at the larval, nymphal, and adult phases. Mammals and birds are blacklegged ticks preferred targets. Larval and nymphal ticks generally feed on North American rodents such as mice, chipmunks, and squirrels. They will also feed on various other mammals such as opossums, raccoons, and deer. Ticks, unbenounced to some, are not born with the Lyme disease-causing bacterium, B. borgdorferi. They acquire this bacteria during a blood meal on an infected animal.

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White-footed mouse (Peromyscus leucopus), which thrive in close habitation to human-built environments, is the most likely reservoir host of the Lyme disease-causing bacterium (B. burgdorferi).open_in_new White-footed mice are carriers of the bacteria but are asymptomatic for Lyme. A tick, usually during the larval or nymphal stage, will feed on a white-footed mouse and, if the mouse is infected with (B. burgdorferi), the tick can become a carrier of the disease.

Blacklegged tick nymph
Ticks in the nymphal stage are the most dangerous for transmitting the Lyme disease-causing bacterium because they are a small and hard to see which makes them more likely to attach long enough to transmit bacteria into the host.open_in_new There is no consensus among scientists about the minimum amount of time this takes, but, generally, the tick has to be attached +24 hours for B. borgdorferi transmission.open_in_new Ticks can transfer this bacteria to any animal they feed on once infected. The eggs laid by an infected adult, however, do not contain the bacteria–the new offspring would need to feed on an infected host to acquire Lyme disease-causing bacterium, Borrelia borgdorferi.

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White-tailed deer (O. virginianus) are a favorite vertebrate host for adult ticks. Look closely at the image above, what appear to be sores on this deer, are actually engorged ticks. By the time an adult tick feeds on a deer, they are either infected with Lyme disease-causing bacterium, B. borgdorferi, or not. Deer do not transmit this bacteria to the tick. Deer act as transporters for ticks as they move through habitats and as a date site for adult males and females to find one another to reproduce.open_in_new

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Deer populations are growing in suburban and urban areas.open_in_new Deer have few remaining predators in areas where laws forbid hunting. This allows deer populations in some regions to skyrocket. And, accompanying an increase in deer populations is an increase in ticks populations.open_in_new

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The why of this relationship is fascinating. Aside from being a site for blood meals and reproduction–deer, mice, and ticks all thrive in patchy ecosystems created by forest fragmentation (depicted above in image of Ithaca, New York). Forest fragmentation describes the patches of forest that result when larger forested areas are divided by development. The resulting patches are often pushed-up against human-created habitats such as fallow fields, abandoned lots, fields of invasive shrubs, a suburban or urban neighborhoods, etc.open_in_new Do ticks thrive in these environments because that is where their preferred hosts thrive, or for other ecological reasons? Researchers are trying to understand this phenomena more thoroughly; but, the fragmentation theory does help explain the rise of tick populations and increasing Lyme disease transmission to humans.open_in_new Ticks follow their hosts. If mice and deer can live near humans, so, too, can ticks.

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To date, however, none of the observed changes in risk of exposure to I. scapularis or B. burgdorferi can be conclusively linked to climate change even though this may be a very likely cause or cofactor.

Rebecca J. Eisen
Climate Change adds another layer to the complex ecological landscape of blacklegged ticks. Projections are hard to make given the complexities of the tick life cycle; but, speculative studies indicate that as temperatures warm at higher latitudes the northern and western range of the blacklegged tick could expand. As temperatures in its southern range increase and rainfall decreases, populations may contract in the south. Ticks will continue to be limited by dry regions lacking humid conditions or regions that become too hot or too cold for ticks to thrive. The exact range expansion or contraction will depend on how climate change continues in North America.open_in_new

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The short story of the long story is ticks are tricky. Ticks’ long life cycles, coupled with their ability to ride-out fluctuations in temperatures, their flexible feeding schedule, and their ability to thrive in human-created landscapes make them hard to pin down. Using this complex network of information, we’ve made specific land-management recommendations for individual homeowners to implement to minimize tick populations. There are no silver-bullets. There rarely are in complex, ecological systems. Addressing this issue using multiple strategies is our best bet in minimizing tick populations in yards and community green spaces.

Continue to article: Managing Yards and Green Spaces to Minimize Tick Populations

 

Download Educational Guides Inspired by the Cornell Lab’s Books

Wed, 07/05/2017 - 09:26

 

EDUCATIONAL GUIDES INSPIRED BY THE CORNELL LAB’S BOOKS

Birdsleuth has created these Educational Guides to help educators of all kinds use Cornell Lab Publishing Group books to inspire learning and fun.
The hands-on activities within the Guides are tied to national education standards, and are parent and teacher tested and approved!
Check back as the diversity of Educational Guides will continue to grow!

A PERFECT DAY FOR AN ALBATROSS
Written and Illustrated by Caren Loebel-Fried
Purchase a copy of the book
Guide overview and supplemental materials

ON DUCK POND
Written by Jane Yolen and Illustrated by Bob Marstall
Purchase a copy of the book
Guide overview and supplemental material

AM I LIKE YOU?

Written by Laura Erickson and Brian Sockin and Illustrated by Anna Rettberg
Purchase a copy of the book
Guide overview and supplemental materials

 

ON BIRD HILL
Written by Jane Yolen and Illustrated by Bob Marstall
Purchase a copy of the book
Guide overview and supplemental materials

Home Tweet Home Photo Contest

Sat, 07/01/2017 - 15:42
  • HOME TWEET HOMEupload and share photos
    Home Tweet Home
    Are you watching nests? Take photos and win prizes! For the month of July, enter your photos of nests here for chances to win. Entering is easy, just upload one or more photos of the nesting cycle to any or all of these categories, including Beautiful Eggs, Cutest Baby, Feeding Time, and Best Nest! And while you’re taking photos, become an official NestWatcher and record what you’re seeing in our scientific database! Contest starts July 1!PRIZES
    There will be prizes awarded to the entry with the highest vote in each category along with a first and second overall prize. Prizes will be awarded at the end of the contest period (August 1st).

    1st Prize
    Deluxe Pennington Bird Feeder & the book Nests: Fifty Nests and the Birds That Built Them by Sharon Beals
    plus a Cornell Lab of Ornithology prize pack2nd Prize
    Pennington Cedar Chickadee Nest Box & the book Nests: Fifty Nests and the Birds That Built Them by Sharon Beals
    plus a Cornell Lab of Ornithology prize pack4 Category Winners
    Cornell Lab of Ornithology prize pack
    A tote bag, birdwatching journal and pen, water bottle, window clings, and Voices of North American Owls downloadposterWe’ll also hand out some NestWatch Cavity Nesting Birds posters to our personal favorites!
    ATTENTION PLEASE
    Before going out to find nests, take a few minutes to learn a little about how to observe nests without harming the birds, and read our best practices for photographing nests. Please don’t handle eggs, nests, or nestlings in order to improve a shot.
    CATEGORIES
    categoryname
    Beautiful Eggs
    84 Submissions
    categoryname
    Best Nest
    171 Submissions
    categoryname
    Cutest Baby
    267 Submissions
    categoryname
    Feeding Time
    208 Submissions

Dance Moves Support Evidence for New Bird-of-Paradise Species

Fri, 06/30/2017 - 16:36

Superb Bird-of-Paradise Lophorina superba © Tim Laman ML 62128001
Dance Moves Support Evidence for New Bird-of-Paradise Species
30 Jun 2017
The Superb Bird-of-Paradise—the shape-shifting black bird of central New Guinea that woos its mate with an iridescent blue “smiley-face” dance—has an equally superb cousin in the isolated mountains of Indonesia’s Bird’s Head Peninsula in the island’s far west. Scientist Ed Scholes and photographer Tim Laman, with the Cornell Lab of Ornithology’s Birds-of-Paradise Project, have now visually documented the distinct differences between the western population in the Arfak Mountains and the more common form found elsewhere on the island. Both believe the western form should be considered a new species.
“The courtship dance is different. The vocalizations are different. Even the shape of the displaying male is different,” says Scholes. “For centuries, people thought the Superb Bird-of-Paradise in the mountains of the Bird’s Head region was a little different from the other populations throughout the rest of New Guinea, but no one had ever documented its display in the 200 plus years this bird has been known to occur there.”

“Even after many trips to the region, we’d never seen the Arfak birds do their courtship display,” says Birds-of-Paradise Project co-leader Tim Laman. “When we finally located a display site and saw a male open his cape for the first time, what we saw was a complete surprise!”

When expanded for courtship display, the western male’s raised cape creates a completely different appearance—crescent-shaped with pointed tips rather than the oval shape of the widespread form of the species. The way the western male dances for the female is also is distinctive, being smooth instead of bouncy.
The raised cape of the western male (left) is crescent shaped and unlike the oval shape of the widespread Superb Bird-of-Paradise (right) found throughout most of New Guinea. Left image © Tim Laman ML 62126951. Right image © Ed Scholes ML 458003.
Scholes and Laman have been studying and filming birds-of-paradise behavior in the Arfak Mountains for the past 13 years. They first uncovered this population’s unique courtship behaviors in June 2016 and returned again this year to gather additional documentation for a forthcoming scientific paper.

A recently published independent genetic study confirms the visual and behavioral evidence collected by Scholes and Laman. A team of researchers from Sweden and Australia used DNA samples from museum specimens to examine the evolutionary relationships among Superb Bird-of-Paradise forms throughout New Guinea. Their research, published online in the Zoological Journal of the Linnean Society, found that the western form is more genetically distinct from the widespread form than previously thought. They, too, say the western population should be recognized as a full species called Lophorina neidda inopinata.

“The timing of this DNA-based study is perfect,” said Ed Scholes, “because it is great to have our field observations supported by solid genetic evidence. We really appreciate this in-depth study of the evolutionary relationships among the different forms of Superb Bird-of-Paradise.”

The Cornell Lab’s Birds-of-Paradise Project (birdsofparadiseproject.org) is a research and education initiative to document, interpret, and protect the birds-of-paradise, their native environments, and the other biodiversity of the New Guinea region—one of the largest remaining tropical wildernesses on the planet.

Cornell Lab of Ornithology Press Release published June 29, 2017.

July 4 Bald Eagle Gallery

Fri, 06/30/2017 - 13:56
Happy Fourth of July! America’s national bird since 1782, the Bald Eagle is an enduring symbol of freedom. Photo by Karen E. Brown via Birdshare. A Bald Eagle snatches a fish from the water. Bald Eagles will soar directly over their prey before suddenly pouncing with one or both feet. Photo by Brian Kushner via Birdshare. An adult Bald Eagle with a juvenile. The young bird will not develop the adult’s distinctive white head feathers until it is about five years old. Photo by Jeff Rawes via Birdshare.Photo by Mitch Vanbeekum via Birdshare.Look at its breath! For such a large bird, Bald Eagles emit surprisingly weak calls. Photo by Simon Richards via Birdshare. How majestic! A Bald Eagle’s wingspan ranges from 5.5 to 8 feet, with females being about 25 percent larger than males. Photo by Susan Newgewirtz via Birdshare.Two Bald Eagles lock talons in courtship. Such rituals include acrobatic displays like cartwheels and high-speed chases. Photo by Jon McRay (Nikographer) via Birdshare. A parent keeps watch over its chicks. Nestlings develop rapidly, leaving the nest as early as eight weeks old. Photo by Keith Williams via Birdshare.A Bald Eagle carries a branch to its nest. Both the male and the female build the nest, which may take from four days to three months to complete. Photo by Priscilla Morris/GBBC.Photo by Margaret Viens/Macaulay Library.A Bald Eagle grasps its prey. Fish are Bald Eagles’ favorite food, accounting for 56 percent of their diet. Photo by Brian Kushner via Birdshare.A young Bald Eagle swoops down on an unsuspecting crow. You can identify immature bald eagles by their dark brown plumage. Photo by Tony Varela/Macaulay Library. The unusual partially-colored plumage on this Bald Eagle is called “dilute.” Photo by Shravan Sundaram via Birdshare.A parent and its youngster perched on their nest. Bald Eagles often use the same nest from year to year. Photo by Susan Schalbe via Birdshare.PreviousNext

Bird Academy Giveaway: How to Identify Bird Songs

Fri, 06/30/2017 - 11:00
Bird Academy giveaway: How to Identify Bird Songs

30 June 2017

Dickcissel by Marc Favre/Macaulay Library

As summer winds down across much of the Northern Hemisphere, there’s still a lot of bird song to be heard. Want to improve your audio birding skills? Or perhaps brush up on how to learn song before the austral summer? We’re excited to partner with the Cornell Lab’s Bird Academy to offer a suite of exciting educational resources in thanks for your eBirding: in July, every eligible checklist that you submit gives you a chance to get free access to Be a Better Birder: How to Identify Bird Songs.

Ten lucky eBirders will get this course for free from their July eBirding! If you like taking part in the eBirder of the Month Challenges, here are even more excuses to motivate yourself to get out birding. Each month of 2017 will feature a different Bird Academy course offering—tune in at the start of August to see what’s on tap for next month.

The Female Bird Song Project

Wed, 06/14/2017 - 15:30

Female Bird Song Project

14 June 2017

Baltimore Oriole by Marky M/Macaulay Library
by Karan Odom
Most birders know that males of many bird species sing. Less well known is that females of many species sing too – and that their songs can often be equally beautiful and complex. In fact, recent research shows that females sing in about 2/3 of songbird species, and that female songs likely evolved alongside male songs in the early ancestors of modern songbirds. Yet, female songs are greatly underrepresented in recording collections. For researchers to understand how songbirds evolved their diverse songs, we need recordings of female songs from around the world. This is a daunting task. The Female Bird Song Project is asking birders, like yourself, to help observe and record female songs through your eBird checklists. Read more to find out how you can help!

How can you help?

First, be aware that female songbirds sing. Do not assume that a singing bird is male. Females sing in many dimorphic species, where females and males look different (download a full list of species with known female song here). By making sure you see the singer, you may be able to record unexpected instances of female song. It is also important to be aware of when you do not know the sex of the bird. In looking through Macaulay Library recordings (including those coming in via eBird), I am finding that recordists will label recordings of singing birds as male, even in monomorphic species that cannot easily be identified to sex in the field. Singing is often associated with breeding behaviors, such as copulating or nest building, in monomorphic species, and careful observation of these behaviors can provide clues as to which bird is which sex. Here are some tips on recognizing females in dimorphic and monomorphic species. Most important is to know when you can and cannot tell which sex is which.

Second, note how you determined sex. When you upload recordings or enter an observation of female song, always select something for the field requesting sex of the bird. If you can’t tell, select sex: ‘unknown’. It is valuable for researchers using your data know when you could not determine sex. If you do indicate sex, please use the Species Comments field to explain how you knew the bird was female or male. Describe the plumage, behavior, or what was distinctive about the individual that allowed you to determine sex. If you are uploading audio or video recording the bird, your audio announcement in the recording should note which bird is which sex, when each vocalizes, and how you knew the sex. Observations and recordings with comprehensive written and verbal notes are the most valuable to researchers now and into the future.

Red-winged Fairywren is a species with known female song. Photo by John Van Doorn/Macaulay Library.

Third, submit your observations and recordings. All media (photos, audio, and video) uploaded through eBird contribute to the Cornell Lab of Ornithology’s Macaulay Library. Submitting your observations and recordings to lasting online collections ensures that they can be found and used by researchers. Learn how to upload media through eBird here. Lastly, and most importantly, enter the exact phrase: “Contributed for the female bird song project: femalebirdsong.org” in your species comments. This will ensure that your observations and recordings of female songs are recognized as part of the Female Bird Song Project. All observations, audio recordings, or videos of female bird songs will help.

To learn more about female bird song, see Lauryn Benedict and Karan Odom’s article in the April issue of Birding Magazine.

Thanks to Karan Odom, a postdoctoral researcher at the Cornell Lab of Ornithology, for this article. Please see her website, The Female Bird Song Project website, Facebook page, or twitter account (@femalebirdsong) for more information, as well as these references used in this article:

Odom et al. 2014. Nature Communications: 3379. doi:10.1038/ncomms4379

Webb et al. 2016. Frontiers in Ecology and Evolution. doi.org/10.3389/fevo.2016.00022

Soaring in Circles: Two Road Trips to See California Condors, Thirty Years Apart

Mon, 06/12/2017 - 20:22
The author’s father, Bob Powell, took every opportunity to take his family on birding expeditions, like this one with his son Giles in Arizona, 1973. Photo courtesy Powell family.

In late July of 1981, my father came home and asked me and my younger brother, Giles, if we wanted to go to California to look for condors. Be warned, he said: “It will be a knock-down, drag-out, no-holds-barred birding adventure with no concessions for kiddies.”

We said yes.

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That Saturday morning, we got in our Chevy Suburban and my father drove 925 miles in one day to Mt. Pinos, California, one of the most reliable condor lookout points remaining, from our home at Holloman Air Force Base in New Mexico.

At the time, as a 12-year-old kid, I thought we were just going on another of my dad’s adventures. I didn’t appreciate that he was seizing a moment, or that later in that same decade, these great vultures were going to vanish from the skies. Now I’m middle-aged, and condors are flying free once again, in 10 times their 1981 numbers. If not for the foresight of the Endangered Species Act, we would have lost this largest North American bird entirely.

After our trip, my father wrote in his bird journal, “I believe that by my death, the only remaining condors will be in zoos.” He’s going to be wrong about that.

But while California Condors are a spectacular success story, much like Bald Eagles and Peregrine Falcons, there’s one glaring difference—we haven’t really gained the bird back. Their number-one problem—poisoning from lead ammunition—has yet to be solved.  Even with the Endangered Species Act, the bird is still doomed, not to extinction but to constant maintenance, and always vulnerable to political vicissitudes that might end the recovery program.

“If you had asked me, ‘Is it worth spending however many millions of dollars on this species?’ I don’t know,” says Noel Snyder, who led the condor recovery program for the U.S. Fish and Wildlife Service during a crucial period in the early 1980s. “I’m very fond of condors and in some sense I’m very glad. But if it doesn’t go any farther than right now, basically you haven’t saved the bird.”

The California Condor is North America’s largest bird. Their broad wings and massive bodies give them a powerful presence in the air. Photo by Gregory Smith via a Creative Commons license.

We had only been in California for about 18 hours when we saw ours. We had spent the night in the back of the Suburban and by 9 a.m. we were on the 8,800-foot summit of Mt. Pinos. Below us, canyon slopes stood like great chevrons with gray-green chaparral spreading over them.

My father was an Air Force fighter pilot and had eyes like a bird of prey. He picked up a dot over the sides of Mount Able. “Maybe 4, 5 miles,” he wrote later, in his daily bird journal. The two main confusion species were Turkey Vultures and Cessna twin-engine aircraft.

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Update your browser or Flash plugin Listen to Bob Powell recounting his trip to Mt. Pinos to look for California Condors. Recorded in 2016 by Hugh Powell.

This dot was large, flat-winged, and so steady in the air it seemed not to be moving. “We watched it and said, ‘Well, could it be, might it be? It’s not flapping,’” my father recalls. “And all of a sudden it took a big double dip”—wings bending up and back down again, wingtips almost touching—“which is kind of a distinctive flight mode for the condor, and it kept coming slowly but surely.” That was the only wingbeat we ever saw it take.

After about 20 minutes the condor came right over the top of us. A little bird was harassing it the way a Red-winged Blackbird harries a crow, except this little bird was a Red-tailed Hawk.

I remember the condor’s massive wings filling the view of my 7×35 binoculars. The fingered primaries curved upward as clear California air rushed past the wingtips, holding the bird aloft. The white triangles in the underwing gleamed in the light, with just a few black feathers mixed among them. The bird wore no wing tags, because no condors at that time had ever been tagged. Today, they all are.

A watch-for-condors sign along the dirt road to the condor recovery program’s field headquarters on the Hopper Mountain National Wildlife Refuge. Photo by Hugh Powell.

Very few people in 1981 recognized lead poisoning as a problem for California Condors, and nobody had any evidence. Conventional wisdom still held that condors were too big, too slow to reproduce, too dependent on large game. They were a “senile species,” according to one account, and the writing had been on the wall ever since the mammoths had disappeared. Condor recovery consisted of watching them from a distance and trying to preserve large tracts of wilderness so they could be left alone.

Things started to change in 1980, when Snyder took the helm of the recovery program. He wanted to use new technology to track where condors went and to breed them in captivity. But the team had yet to gain permission for the work, and there was a tooth-and-nail battle going on over whether captive breeding was a viable tactic or a last insult to a doomed species.

A condor's huge flight feathers take a long time to grow in. Regrowing feathers—such as that shorter primary feather second from the wingtip—create a distinctive wing outline that was used to identify and count condors in the 1980s. Read more about molt patterns and bird ages. Photo by John Cancalosi.

Nobody even knew how many condors were left until 1982, when a California Polytechnic professor named Eric Johnson started paying attention to molt patterns. The slow-growing primary feathers created distinctive wing outlines that could be used to identify individuals, much the way humpback whales are catalogued by patterns in their tail flukes. By arming students and volunteers with telephoto lenses and then carefully matching up hundreds of black-and-white prints, the team determined that just 21 condors remained in the wild.

“All of a sudden we knew how many condors there were and it was less than everyone had thought,” Snyder says. The low number helped gain approval for radio-tracking. Though the goal was to learn about condor movements, Snyder says the most important thing radio tags did was lead the team to dead ones.

In 1984, a radio tag led researchers to the body of IC1, the first California Condor known to die of lead poisoning. The next year, two more birds died from lead. There was little else to be done but start building up a captive population.

At the time, no one knew whether it would even be possible to breed California Condors in captivity, so Snyder had begun working with Andean Condors, for practice. By the early 1980s, “we knew that Andean Condors breed like chickens,” he says, and it turned out that California Condors did too, often doubling the yearly output that a wild pair could produce on its own. The team caught the last wild bird on Easter Sunday, 1987. My father’s prediction had come true: for the first time in at least 10,000 years, no condors flew over California.

By 1993 captive breeding had grown the population past 50 individuals, and by 1998 it passed 150. The recovery program still had lots of work to do, such as getting condors properly socialized to each other and unattached to humans, but the imminent prospect of extinction had passed.

What remained was lead.

Lead in Hunted Animals: A Threat to People as Well as Condors When lead bullets strike an animal, they break apart and leave a spray of tiny but toxic fragments in the flesh. Photo courtesy of the Peregrine Fund.

Read more about the problem of lead bullet fragments in meat from deer and other big game in Get the Lead Out, from Autumn 2009 Living Bird.

“If they’re in the wild long enough, they’re going to get lead exposure.” That’s how Myra Finkelstein sums up the problem condors face. Finkelstein runs a lab at the University of California, Santa Cruz, that tests blood samples from wild condors. In the first 14 years after the recovery team began releasing captive-bred birds in 1997, biologists tested 150 different condors for lead a total of 1,154 times. What they found led Finkelstein to publish a paper titled “Lead poisoning and the deceptive recovery of the critically endangered California Condor.” Almost half of all free-flying condors had at some point developed lead levels so high that they needed to be brought to a zoo for emergency treatment. In some years, nearly 9 out of every 10 wild condors showed elevated lead levels.

Lead doesn’t build up in the food chain, or bioaccumulate, the way pollutants like DDT do. That means a condor can’t get lead poisoning just from eating a lead-poisoned animal—it has to consume the lead fragment itself. Unfortunately, it doesn’t take much: lead toxicity is measured in billionths of a gram. The snowstorm of flakes that a bullet sheds as it enters a deer, wild boar, or other animal’s body provides more than enough.

Bullets are almost pure lead, Finkelstein says, “so even a tiny fragment, if it gets in their digestive system and leaches out, can be enough to poison a condor.”

It’s tragic that condors don’t get better with age at avoiding lead. They’re very good at finding carcasses, visiting an estimated 150 per year, but they have no way of learning which ones have been shot. Old veteran condors are just as vulnerable to lead poisoning as a fresh fledgling is.

Because lead poisoning is so direct, tracing it back to its source is fairly easy. By measuring two isotopes of lead, Finkelstein can create something akin to a fingerprint that matches condor blood samples to environmental sources—it’s the same process used to trace lead contamination in homes. With condors, years of research have shown that the animals almost always get their lead exposure from ammunition. Finkelstein’s instruments can unequivocally distinguish between different sources of lead, such as bullets versus old lead paint.

Watch a Condor Chick Grow Up

Her evidence led to a 2008 ban on lead ammunition for big-game hunters in California’s condor country. But it’s been hard to enforce, and there are loopholes: lead bullets are allowed when euthanizing livestock and for controlling “nuisance” animals like coyotes and ground squirrels—all of which are on the condor’s menu.

More On Birds Coming Back From the Brink

As a result, condors showed no drop in lead poisoning after the 2008 ban—a result that pro-lead factions have used to argue for lifting the ban, perceived by some as unfairly scapegoating hunters. In 2013 the lead ammunition ban was expanded to cover all types of hunting and will include the entire state by 2019.

For Finkelstein, lead is a much larger public health issue. “As a society we have recognized that lead is toxic for a very long time, and gotten lead out of paint, and gotten lead out of gas,” she says. Alternatives to lead ammunition are no more anti-hunter than unleaded gas is anti-car, she says: “Changing from lead in gasoline didn’t mean you couldn’t drive your car. It just meant you had to use something else in your tank.”

“It really seemed to me that this was a very solvable problem,” Snyder recalls thinking after the three lead poisonings of the 1980s. “But nobody anticipated how hard the politics would be.”

Meanwhile, the recovery program goes on. Condors continue to breed in captivity, and increasingly in the wild. The recovery team toils to follow radio- tagged birds, set out lead-free carcasses, sweep nests for trash, check eggs for fertility, and capture each of the more than 250 free-flying birds to test for lead twice a year. According to exposure rates in Finkelstein’s 2012 paper, a typical year would see at least 175 of those birds developing elevated lead levels. “Even though I had been working with the data for years, it was still shocking,” Finkelstein says. “These birds are acutely poisoned all the time.”

What if the lead problem could be solved? Finkelstein has run the numbers: “Even if you just got rid of 80 percent of lead poisoning, the population would start increasing, and you would have a positive population growth rate, even without releasing birds.”

Through the Years: In addition to being a birder, Bob Powell was a fighter pilot in the U.S. Air Force. He's pictured here in the cockpit of an F-4 in 1968, the year the author was born.Bob Powell in 2016 with a grandson.The author in 1982, the year after the great condor road trip.The author in 2017, with son. Photos courtesy Powell family.PreviousNext

My dad had budgeted three days to wait for condors on Mt. Pinos. After one buzzed us before lunchtime on the first day, he deployed his contingency plan: head to Yosemite for his lifer Black Swift and Hermit Warbler. These landscapes—Mojave, Ventura, Sequoia, Yosemite—these were what crystallized in my mind as a boy going on adventures. On our way home, my father took a detour in Arizona for Violet-crowned Hummingbird, and then drove us home all night, through pelting thunderstorms, so we wouldn’t have to stay in a motel.

I remember watching his face in the rearview mirror. He was staring out into the raindrops and leaning over the steering wheel to keep himself awake. He was 40 years old—younger than I am today. I had total confidence in this man, who spent his workdays flying faster than the speed of sound. We had seen condors together—a bird that in the adult world was in crisis, but in my world had been almost a sure thing ever since my father had decreed we would go find it.

I didn’t know it then, but the whole reason we had taken this abrupt vacation was a shakeup in his squadron, a kink in his career trajectory he was dismayed to find he could not change. Until then, my father had been an Eagle Scout; a math whiz; a state-champion football player; a rock climber; a war veteran; a knockdown, drag-out birder.

He kept leading us on adventures, switching to small-boat sailing when the Air Force moved us to Florida a couple of years later. But somewhere in this period was a high-water mark, after which I realized birding might not, after all, be the second-coolest activity in the world after flying jets. And that vulnerability is not reserved only for the weak or the small, but can settle its heavy weight anywhere, even onto the largest wings on the continent.

Biologists Joseph Brandt (center) and Jenny Schmidt (right) check the nest of condor #237, who watches, at left. Photo by Hugh Powell.

Thirty-two years later, I returned to California to accompany four condor biologists on a nest check at the Hopper Mountain National Wildlife Refuge, just 20 miles from Mt. Pinos. We hiked through thick chaparral as a hot wind barreled up the slopes and flung fine dust in our eyes.

We stopped at a sheer fin of sandstone with an almond-shaped cave perhaps 50 feet below the ridge. In that alcove, tucked deep in the cool shadows, lay a single egg. Biologists Joseph Brandt of the U.S. Fish and Wildlife Service, and Jenny Schmidt of the L.A. Zoo, put on climbing gear and rappelled down to check the egg.

As we approached, a condor sailed up the canyon toward us, its big body impervious to the buffeting winds. Just before he came overhead he stalled and turned on the air, his great finger-primaries spread against the blue, his legs dangling roughly below him. Rotating slowly in spite of gravity and wind, he completed the circle and began an arc back toward the valley, then abruptly dropped below the ridge and onto the nest entrance. His wing tag was yellow, meaning “200,” and bore the number 37.

This was male #237, at 23 pounds a big bird even for a condor, and “always really standoffish,” according to Brandt, who notes every condor has its own personality. This male and his mate, female #255, had both hatched in captivity in 2001 and were released the following year. This was their fourth nesting attempt each.

Brandt is 6’2”, thick-trunked as a sequoia, with blond dreadlocks. When he arrived at the cave entrance and unclipped from the rope, he didn’t have to bend down to walk in. Schmidt came after, carefully placed the egg in a black bag to block the light and checked it with a flashlight: it was fertile.

Later that month, the pale blue-white egg cracked from within and a chick pushed its way into the world. The little gray nestling became condor #717, a female who is still flying free today.

The Beauty and Biology of Egg Color

Mon, 06/12/2017 - 20:02
More From Living Bird

Fish do it. Frogs do it. Even insects lay eggs with color. But birds do it best.

Only birds produce eggs in such a wide range of eye-pleasing shades and intricate patterns on the hard surface of their eggs.

Like gems in a jeweler’s window, they vary in base color, how shiny they are, and whether they are covered in Sanskrit-like scrawls or patterns of spots.

But, how does the color get there? What is it made of? Does it benefit the embryo? And, why are some eggs plain white?

Egg pigmentation is surprisingly complex.

Building the Egg The production process of eggs resembles a miniature assembly line inside a female bird. Eggs receive their signature color and patterning during the last few hours before they are laid. From Handbook of Bird Biology, Second Edition.

An egg’s story begins in a female bird’s single ovary. When an ovum is released into the oviduct and fertilized, it is just a protein-packed yolk. The albumen—the gelatinous egg white—is added next. The blobby mass then gets plumped up with water and encased in soft, stretchy membrane layers. The first globs of the calcium carbonate shell are then deposited on the exterior, with the mineral squirting from special cells lining the shell gland (uterus). Pigmentation, if any, comes next, with an overall protein coating added before the egg is laid. It takes about 24 hours to build a single egg.

In his book, The Most Perfect Thing: Inside (and Outside) a Bird’s Egg, University of Sheffield zoologist Tim Birkhead compares the pigmentation process to an array of “paint guns.” Each gun is genetically programmed to fire at a certain time so that the signature background color and spotting of a species’ eggs is produced.

“Examination of birds’ oviducts at the time the color is placed on the egg suggests that the color is produced and released over a very short time frame,” Birkhead says, “usually in the last few hours before the egg is laid, and that makes it very hard to study.”

The intricate squiggles of the Great Bowerbird egg make it stunningly beautiful. Photo by John Weinstein, © 2014 The Field Museum. Egg from the collection of the Western Foundation of Vertebrate Zoology. Coatings of Many Colors

Despite the variety of egg colors and patterns, the palette is surprisingly small. Egg pigments are versatile substances made of complex molecules synthesized in a bird’s shell gland. Only two pigments are at work. Protoporphyrin produces reddish-brown colors. Biliverdin produces shades of blue and green. More of one pigment, less of the other, and the egg gets a different background color, spots of a different color, or a combination of both.

Cetti’s Warbler eggs are an intense brick-red. Photo by John Weinstein, © 2014 The Field Museum.

For example, the intense brick-red of Cetti’s Warbler eggs comes from protoporphyrin alone. All birds are likely to have the basic genetic machinery to produce the two pigments, even if they use only one of them, or use none at all and produce plain white eggs.

A female bird needs to take in extra calcium in order to produce the egg­shell, and her diet can also be a factor in the production of the type and quantity of pigments. Paler-than-normal colors may be the by-product of a bird’s poor diet or an immune system challenged by disease. Even in the same clutch, each egg will be pigmented somewhat differently.

All of these eggs were laid by Common Murres. Each has a distinctive color or pattern, possibly to help parents identify their own egg among all the others in a breeding colony. Photo by Pat Leonard; eggs from the Cornell University Museum of Vertebrates.

“Birds that lay multiple eggs, such as thrushes and flycatchers, seem to change the color of their eggs through­out the laying cycle as if they were running out of the pigments,” says Cornell PhD Mark Hauber, who wrote The Book of Eggs and studies them at Hunter College of the City University of New York.

And over time, eggshell colors and patterns within a species can also change. Mark Hauber feels bird-egg pigmentation may have evolved and disappeared multiple times and says it seems to be a rather “pliable” trait.

“With just two mutations, a Japa­nese Quail, which lays beige eggs with brown speckles, can start laying plain blue eggs,” Hauber says. “So, it’s really easy to genetically regulate metabolic pathways to start laying different col­ored eggs.”

The deep history of egg color re­mains unknown. Some scientists think the dinosaur ancestors of birds pro­duced only white eggs, as reptiles still do today, and that pigmentation came later. Others suggest dinosaur eggs could have been blue.

Left: The eggs of the Black Tinamou (top) and the Red-winged Tinamou (bottom) get their high-gloss shine from a protein-based coating. Right: The background color of a Guira Cuckoo egg can range from gray to the lovely turquoise shade shown here. Note along the broken edge, the turquoise color is not just deposited on the surface but permeates the entire shell. Photos of tinamou eggs by John Weinstein © 2014 The Field Museum. Cuckoo egg by Paula and Michael Webster. Finishing Touches

Though all bird eggs are made of calcium carbonate, the underlying shell structure differs among species. The outer coating of the shell—the cuticle—can also make a difference in the finish of the egg. For example, the glossy eggs of the tinamou family—from the reddish-purple egg of the Red-winged Tinamou to the emer­ald green of the Elegant Crested-Tina­mou—give off a high-wattage shine.

The white deposits on the exterior of this Guira Cuckoo egg resemble the surface of the moon. Photo by John Weinstein © 2014 The Field Museum.

The Guira Cuckoo’s egg is a wonder. Before the egg is laid, the base color is covered with a chalky layer of flaky cal­cium carbonate called vaterite that is structurally different from the eggshell itself. During incubation, the outer layer flakes off in patches, revealing a smoky gray or turquoise underneath in intricate patterns, rather like an artist’s scratch­board. It’s one of Hauber’s favorite eggs.

“It’s like having a little jewel in your hand,” he says. “The eggs of some spe­cies of anis are like this, too. Among communal nesters that chalky lay­er might act as a bumper to prevent damage when the eggs knock against each other. We’re trying to figure out if that flaky white material has any pigments in it.”

A Killdeer on its nest with well-camouflaged eggs. Photo by Wayne Bierbaum via Birdshare. Pigmentation as a Parental Cue Semipalmated Plover eggs are laid in the open, and both eggs and chicks are extremely well camouflaged for protection from predators. Photo by Doug Sonerholm via Birdshare.

Some egg pigment functions are well established by science. Camouflage is one. Many species that nest on the ground produce speckled or streaked eggs that blend in well with their surroundings and befuddle predators. Look at the eggs of any shorebird and you’ll find nearly all of them are speckled to blend in among rocks, pebbles, and sand to foil egg-stealing snakes, lizards, squirrels, and raptors.

As a general rule, birds that lay all-white eggs tend to be cavity-nesting species, such as owls and woodpeckers. Their eggs are already hidden from view so there’s no reason to produce pigmented eggs. There’s also a theory that white eggs show up better in a dark cavity.

But, there are exceptions. Even though camouflage makes sense for most species that lay their eggs in nests on the ground, some ground-nesting species—such as tinamous and nightjars—produce bright-colored, conspicuous eggs, which means other forces are at work. It helps to understand a species’ life history.

Great Gray Owls lay dull white, unmarked eggs in old nests built by other birds. Photo by Michael Quinton/Minden Pictures.

Several Great Tinamou females may lay their shiny, unspeckled turquoise eggs on contrasting brown leaf litter in the same depression or scrape on the ground without building an actual nest of sticks or mud. Cornell PhD Patricia Brennan, now at the University of Massachusetts, Amherst, studied these birds in Costa Rica, noting that the eggs are not camouflaged or well concealed despite the threat of predation. Brennan suggests that egg color is a signal to other females, drawing their attention to the nest and promoting synchronous laying. The benefit to the birds is that, even if a predator does strike, it cannot eat all the eggs and those of any one individual stand a better chance of surviving.

Scientists say some species get away with laying conspicuous eggs because the parents sit tightly on the nest, with both male and female sharing round-the-clock incubation duty so the eggs are almost never exposed to view. In fact, another novel, though disputed, explanation for brightly colored, conspicuous eggs is called the “blackmail theory.” Bucknell University’s Daniel Hanley has theorized that, because conspicuous eggs are at greater risk of predation, females may lay them to blackmail their mate into more active participation at the nest. If the male wants the showy eggs to stay covered up and protected, he must take turns incubating on the nest himself or bring food to the female so she can stay on the nest.

Tawny-flanked Prinia eggs (left) often sit side by side in their nest with eggs laid by the Parasitic Weaver (right). The colors are similar, but the weaver cannot replicate the prinia’s fine squiggles. Photo by Claire Spottiswoode. Pigmentation as Identifier

Some eggs are pigmented and patterned in defense against brood parasitism, which is when one species lays its eggs in the nest of another species as a ploy to get host parents to raise its young. Brown-headed Cowbirds are among the most famous nest parasites in North America, inducing Red-winged Blackbirds and other species into caring for cowbird nestlings.

A single, reddish-brown-spotted cowbird egg sits next to three smaller, whiter Yellow Warbler eggs. Photo by Stylurus via Birdshare.

Evolutionary biologist Claire Spottiswoode from the University of Cambridge says egg speckling can be a strategy to help parents differentiate their own eggs from those laid by an intruder. But it doesn’t always work.

“It seems likely that natural selection seized on egg speckling and elaborated upon it to generate the complex egg signatures of identity that we see in host birds,” explains Spottiswoode. “But those patterns can also be mimicked to some degree by their parasites.”

Spottiswoode’s studies of a species called the Parasitic Weaver in Zambia attempt to measure the competing pressures on both host and parasite in what she terms a “coevolutionary arms race.” The battle between host and parasite often plays out in alternating egg pigmentation changes. Over time, the host species alters the look of its eggs, which the parasite then tries to mimic closely enough so that its eggs are not rejected. These changes happen surprisingly quickly—even within a few decades.

Bird eggs from various species can be pigmented in a variety of patterns, including spots, blotches, scrawls, and streaks. Illustration by Katherine A. Smith.

“What we’ve seen in Zambia is primarily a shift in the frequency of existing colors, given that the range of egg pigments is actually quite limited,” Spottiswoode says. “We know from other systems that natural selection can sometimes be startlingly effective in generating evolutionary change and that eons aren’t always needed!”

But again, nature throws in a few wrinkles that are hard to explain. For example, the Tawny-flanked Prinia produces fine squiggles on its eggs that are impossible for Parasitic Weavers to replicate, yet the weaver often successfully parasitizes prinia nests.

“This is a real mystery to me because having apparently evolved a perfect signature, the prinias seem not to use it,” Spottiswoode says. “Unsquiggled eggs are clearly accepted at least sometimes, otherwise this strain of parasites would be defeated and have died out.”

“Robin’s-egg blue” isn’t just a fanciful term: American Robins and many other thrushes lay eggs that are a lovely sky-blue to blue-green color. Photo by Steve Fisher via Birdshare. Ten Cool Facts About Eggs Ostrich egg. Photo by Jabruson/Minden Pictures.
  1. In passerines, eggshell formation takes place mainly at night.
  2. Depending on species, eggshells can have anywhere from a few hundred pores to tens of thousands.
  3. An egg loses 18 percent of its mass, on average, between laying and hatching, mostly from water loss through shell pores.
  4. The size of the air cell is smaller in newly laid eggs, so they sink in water. Older eggs have more air space and will float.
  5. More than 100 types of antimicrobial enzymes are found in albumen, the egg white.
  6. Regardless of an egg’s position, the yolk rotates so that in the early stages of development the embryo always floats to the top.
  7. Up to 10 percent of the calcium used for shell formation can come from the female’s bones.
  8. A bird’s ovum must be penetrated by multiple sperm in order for the embryo to develop.
  9. Precocial chicks, which hatch covered in downy feathers, come from larger yolks. Altricial chicks, which hatch naked, come from smaller yolks. With less food available inside the egg, the latter hatch at an earlier stage of development.
  10. The egg of an Ostrich is the largest living cell on Earth.

Source: The Most Perfect Thing, by Tim Birkhead; Handbook of Bird Biology, 2nd edition. Cornell Lab of Ornithology.
Pigmentation as Sun Block

Pigment may also have a specific func­tion related to sunlight. David Lahti, at Queens College of the City Universi­ty of New York, and Cornell PhD Dan Ardia at Franklin and Marshall College, studied specimens of Village Weaver eggs from Africa, which naturally vary from white to blue-green. Their theory is that egg color can represent a balanc­ing act between two impacts of light—one good, one bad.

“There must be a trade-off between embryo protection from damaging UV rays, what we call the parasol effect, and the cost of additional pigmenta­tion causing overheating, the dark-car effect,” Ardia explains. “We found good evidence that DNA-damaging UV light transmits more easily through the egg­shell when there isn’t much pigmen­tation. But heavily pigmented eggs do heat up faster, which is also very dan­gerous for the embryo.”

Lahti plans further studies to explore whether light levels have an influence on egg colors in other species.

Multiple studies have examined egg color in relation to the embryo’s growth. Some theories suggest that variable amounts of pigment at each end of an egg allow differing levels of light to filter through, which may help the embryo develop a sense of direction and also cue the development of specific structures in its body. Another idea is that darker or lighter colors among eggs in the same clutch might play a role in whether the eggs hatch all at once or in sequence.

Some researchers think the intensity of an egg’s color may say something about the health of the female bird, important information for males who may be decid­ing how much time to invest in incubat­ing eggs and bringing food to the nest.

“There are many competing hy­potheses to explain egg coloration and they’re not all mutually exclusive,” Ardia points out. “Pigment function is almost surely a complicated combination of factors depending on the idiosyncrasies of each species.”

More Questions

Despite the research already done on the colors and patterns of bird eggs, plenty of questions remain.

For example, what do the birds see when they look at the eggs? Mark Hau­ber’s lab is investigating how some birds see more of the light spectrum than hu­mans do.

“Some birds, such as most galliforms or ducks, don’t see ultraviolet light,” Hauber explains. “But some gulls, hum­mingbirds, most songbirds, and even ostriches do see UV light and might be picking up more information from egg colors and patterns than we can see.”

Lahti is fascinated by instances in which some birds lay only blue eggs, but other individuals of the same species lay only white eggs, as is the case with East­ern Bluebirds.

A New Guide for Bird Egg ID

The Cornell Lab of Ornithology and Waterford Press have teamed up to offer a series of handy, folding pocket field guides about birds, including a guide to identifying nests and eggs for North American backyard birds. The guide includes illustrations and descriptions of eggs and nests for 24 common bird species.

“I don’t know what’s going on there,” he says. “Bluebirds are in the Turdidae family in which nearly all species have blue eggs. But bluebirds may be mak­ing an evolutionary transition to white eggs, which would be expected since they nest in cavities or nest boxes.”

“One persistent mystery is why many open-nesters like the American Robin lay blue eggs. Is this camouflage? Does it sig­nal, as one study strongly suggests, female quality? We don’t know,” muses Birkhead. “Among other species, we also don’t know how those exquisite pencil-like scribbles are produced on some eggs.”

Whether scientists are trying to un­lock their secrets, or simply enjoy their beauty, bird eggs are one of nature’s lit­tle miracles—a fragile, self-contained, breathable package evolved to protect the tender bud of life unfolding within.

A New Guide for Bird Egg ID The Cornell Lab of Ornithology and Waterford Press have teamed up to offer a series of handy, folding pocket field guides about birds, including a Nests and Eggs guide for North American backyard birds. The guide includes illustrations and descriptions of eggs and nests for 24 common bird species. Find out more. [/sidebar]-->

Analysis: The Economic Value of Birds

Mon, 06/12/2017 - 19:54

For ornithologists, bird watchers, and many people who enjoy birds, the idea of calculating the economic value of birds as pest-control agents, pollinators, carcass cleaners, and various other ecosystem service providers may be off-putting. I still feel offended when anyone asks me: “Why should we care about birds?”

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As director of an environmental organization, I have to answer that question regularly, for everyone from impoverished villagers to Turkey’s president. My instinctive response is: “Because they exist, and it is immoral to kill other creatures and destroy their habitats.”

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However, this reply is rarely convincing. On the other hand, talking about the ecological and economic benefits of birds raises peoples’ interest and support for bird conservation.

As ornithologist Matt Johnson puts it elegantly: “The fact that you pay a plumber for his services does not diminish his personal value as a father, friend, or human being.

Knowing that healthy vulture populations can save human lives by reducing the incidence of rabies does not make them any less magnificent. But it’s the increases in rabies deaths in some areas that have prompted interest in vulture conservation among people I have talked to, from garbage men in Turkey to government officials in Ethiopia.

With birds’ ecological roles and their economic consequences in mind, I—along with my co-editors, visiting professor Chris Whelan of the University of Illinois at Chicago and biologist Dan Wenny of San Francisco Bay Bird Observatory—recently published the book Why Birds Matter.

The book provides an overview of birds’ ecological functions and ecosystem services, which typically fall into one of four categories:

  • Provisioning services, such as game meat for food, down for garments, and guano for fertilizer;
  • Regulating services, such as scavenging carcasses and waste, controlling populations of invertebrate and vertebrate pests, pollinating plants, and dispersing seeds;
  • Supporting services, such as cycling nutrients, and even contributing to soil formation; and,
  • Cultural services, exemplified by birds’ prominent roles in art and religion and by the billions of dollars spent on bird watching.

Since much has been written, by myself and others, about the economic importance of bird watching and hunting, I am going to focus on a few of the other services provided by birds with some economic examples from our book. Only a small fraction of bird ecosystem services have been evaluated economically, but even these few examples show how birds are critical for the healthy functioning of ecosystems and contribute billions of dollars to the world’s GDP.

Eurasian Jays plant seeds in a service worth thousands of dollars in human labor savings. Photo by Bengt Lundberg/Minden Pictures. Seed Dispersal and Pollination

Seed dispersal may be the most important bird ecological function. In some tropical forests, birds disperse up to 92 percent of all tree and woody species, including 85 timber species, 182 genera of edible plants (including spices), 153 medicinal plants, 146 ornamental plants, and 84 genera with other economic or cultural uses.

Find out More: Birds and Seed Dispersal

Some important tree species, such as African mahoganies (Meliaceae), depend on a few specialized avian dispersers. The disappearance of large frugivorous birds such as hornbills and curassows is economically detrimental because many bird-dispersed timber tree species, such as Antiaris toxicaria in Ghana, have very large seeds and only large birds can disperse the seeds. Indeed, two valuable African mahogany species, Entandrophragma utile and Khaya anthotheca, rely almost entirely on birds for seed dispersal.

Clark's Nutcracker by Luis Villablanca.[/caption] Find out More: Birds and Seed Dispersal

Soul Mates: Nutcrackers, Whitebark Pine, and a Bond That Holds an Ecosystem Together

Jays And Crows Act As Ecosystem Engineers Jay And Pine Intertwined

Where Is That Bird Going With That Seed? It’s Caching Food For Later

[/sidebar]-->Even though there are far fewer bird-dispersed plants in temperate regions, birds’ economic value there can still be substantial. In Sweden’s Stockholm National Urban Park, the human labor cost of replacing the seeding or planting of tree seeds by Eurasian Jays was estimated to be $2,450 to $11,250 per bird and $210,000 to $950,000 across the park. According to Diana Tomback, a professor of forest ecology at the University of Colorado at Denver, the estimated cost of replacing Clark’s Nutcrackers’ seed dispersal of whitebark pine is $1,980 to $2,405 per hectare and $11.4 to $13.9 billion across the range of whitebark pines in the U.S.

Though bird pollination is less common than seed dispersal, it is important in certain regions, such as Australia, Oceania, and Andean cloud forests, and for certain plant groups, such as tropical understory herbs. Despite limited research, birds are thought to pollinate between 3 and 5 percent of more than 1,500 species of crop or medicinal plants, three-quarters of which cannot self-pollinate. Studies on commercial plants—such as Eucalyptus, feijoa, loquat, silky oak, and red silk cotton tree—indicate that birds may be providing higher-quality pollination of mixed-mating tree crops than insects, such as honeybees. As shown by the ecologist Sandra Anderson of the University of Auckland and coauthors in our book, bird pollination has been overlooked, especially in winter when most insects are inactive.

Bay-breasted Warblers and many other bird species help control pest populations in timber stands. Photo by Arni Stinnissen/ArniWorks Nature Photography. Pest Control

Avian control of insects that do damage to plants can have a large economic value. Birds can reduce the intensity of spruce budworm outbreaks and mitigate damage on spruce tree plantations comparable to effective insecticides. In Washington, avian control of spruce budworm was calculated to be worth at least $1,473 per square kilometer per year.

Insectivorous species, such as this Gray-headed Kingfisher in Africa, provide valuable pest control services to local farms. Photo by Çağan H. Şekercioğlu.

Insectivorous birds have been observed to reduce insect pest damage in various agricultural systems, such as apples, broccoli, cacao, coffee, corn, kale, grapes, and oil palm. For example, in Dutch apple plantations, researchers found that birds’ reduction of insect pest damage translated to a 66 percent increase in the yield of domestic apples. Similarly, researchers in Borneo estimated that bird pest control prevented 9 to 26 percent of the fruit loss in oil palm plantations. Matt Johnson and colleagues discovered that by reducing the damage caused by coffee berry borer beetles, birds in Jamaican coffee plantations increased coffee yield and farmers’ income by $310 per hectare.

We know less about birds of prey as pest control agents. But we do know that in its lifetime a Barn Owl may eat more than 11,000 mice that would have consumed 13 tons of crops. Field experiments in Israel with a trained Barn Owl revealed that the presence of an avian predator creates a “landscape of fear” that can significantly reduce seed consumption by small rodents. Owls have also been shown to control rat populations in various field crops, such as wheat, rice, and corn. In Malaysia, oil palm farmers put up Barn Owl nest boxes when local rodents developed resistance to the rodenticide warfarin. The switch to owls had the added benefit of population increases of other species that were being poisoned by warfarin, including mammalian predators, such as common palm civets and leopard cats.

A Barn Owl with prey. Photo by Tony Rawson via Birdshare.

Birds can even be used to control the populations of other birds that are considered nuisances. In New Zealand, falcons in vineyards decreased the abundance of pest bird species and reduced grape loss by 95 percent. At airports, raptors can be especially important in keeping away birds that regularly collide with aircraft. The U.S. Air Force paid $200,000 per year for trained Peregrine Falcons to drive away European Starlings, Canada Geese, and other birds around the McGuire Air Force Base.

Any discussion of birds as pest-control agents should also mention that birds tend to be overestimated as pests themselves. Agricultural damage estimates by granivorous birds are often exaggerated. In surveys, farmers estimated they were losing an average of 25 percent of their crops to birds, due to subjective impressions based on the conspicuousness of large and localized bird flocks. But studies of damage to various crops, including cereal, corn, rice, and sorghum, by species such as Red-winged Blackbirds, Dickcissels, and Red-billed Queleas have shown that actual damage amounts to less than 1 percent of production.

Scavengers and Sanitary Services A Turkey Vulture cleans up a carcass. Photo by Brian Kushner via Birdshare.

Carcass-removal services of vultures in Spain alone led to a minimum annual savings of about €1 million, because without vultures the carcasses of free-ranging livestock must be disposed of professionally. Vultures are particularly important in developing countries where sanitary waste programs may be limited or nonexistent. Vultures possess the ability to resist and possibly detoxify bacterial toxins in rotting flesh. Extremely acidic secretions of the vulture stomach kill all but the most resistant spores, reducing the pathogenic bacteria by consuming carcasses and thereby reducing disease.

Unfortunately, Old World vulture populations have drastically declined. In India, vulture populations crashed in the 1990s as vultures were poisoned while feeding on the carcasses of livestock that had been administered the veterinary drug diclofenac, which causes kidney failure in vultures. As vultures disappeared, there were increases in rotting animal carcasses. With fewer carcasses consumed by vultures, feral dog and rat numbers went up. At one Indian garbage dump, there was a 20-fold increase in the number of feral dogs.

The increase in these potential disease vectors led to an increase in rabies, and possibly caused the 1994 bubonic plague outbreak in western India that killed 54 people and cost India over $2 billion. Economist Anil Markandya and colleagues calculated that from 1992 to 2006 alone, the disappearance of vultures led to approximately 48,000 additional human rabies deaths and cost $34 billion to the Indian economy.

Even though diclofenac was banned for veterinary use in India and Pakistan, it was recently permitted by Tanzania. Thousands of African vultures die from eating poisoned carcasses, and now their populations are crashing in sub-Saharan Africa.

Losing Birds and Their Ecosystem Services About the Author

Çağan H. Şekercioğlu is a professor of biology at the University of Utah and an author of Why Birds Matter: Avian Ecological Function and Ecosystem Services, University of Chicago Press. Follow him on Instagram and Twitter: @WhyBirdsMatter.

According to the IUCN Red List, 23 percent of the world’s birds are threatened or near-threatened with extinction, and 44 percent have declining populations. Bird extinctions and population reductions are already disrupting important ecosystem processes. Many bird species, such as Southern Cassowaries and Three-wattled Bellbirds, have irreplaceable roles as efficient dispersers of large-seeded plants.

The societal importance of ecosystem services is often appreciated only upon their loss. When introduced red foxes wiped out seabird colonies and their nutrient-rich guano from some Aleutian islands, the entire ecosystem changed from lush grassland to tundra. The loss of birds can change entire ecosystems.

Investments in understanding and preventing declines in populations of birds and other organisms will pay off, but only while we still have time to act.

View from Sapsucker Woods: Endowing a Future for the Kirtland’s Warbler

Mon, 06/12/2017 - 16:25

 

Birds are remarkably resilient creatures. Over the past century, spectacular examples demonstrate that even the most endangered, vulnerable species can turn the corner once we uncover and eliminate the environmental problems that were driving them downward. It is hard to imagine, for example, that Snowy Egrets and other wading birds that are common today were once on the verge of extinction in North America until we stopped hunting them for the plume trade. Depleted waterfowl populations rebounded after harvest quotas, wetland protection, and science-based monitoring were introduced at continental scales. Bald Eagles, Peregrine Falcons, and Brown Pelicans flourished once again following the banning of DDT and related pesticides in the 1970s. With such high-profile successes mounting, the species-recovery formula codified by our Endangered Species Act might seem straightforward: remove the stressors, ensure sufficient habitat, and the species will recover.

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In many respects, the Kirtland’s Warbler represents yet another textbook case of recovery. Given how bleak their prognosis looked in the early 1970s, today’s breeding population (more than 2,000 breeding pairs) and last year’s disbanding of the Kirtland’s Warbler Recovery Team might warrant highest honors on the All-Star Team of endangered species recoveries. Unlike the success stories mentioned above, however, this case has one huge caveat that illustrates an emerging dilemma in endangered species management. The dilemma even has a name: the Kirtland’s Warbler is a “conservation-reliant species,” meaning that its continued recovery and longterm persistence will require perpetual input of management energy and financial resources by humans.

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Can we really call a species “recovered” if we have to keep pouring in resources in order to ensure its sustainability? Not only do I think we can, but I regard the evolution of thinking and organizing around the future of the Kirtland’s Warbler to be a model for how we ought to approach all conservation-reliant cases. To begin with, last year’s transition away from a Recovery Team was more of a hand-off than an outright disbanding, because the Kirtland’s Warbler Conservation Team formed simultaneously, and included many of the same experts. This conservation team is already acting on the full set of detailed recommendations provided by the outgoing recovery team. Three separate working groups attend to issues related to breeding grounds, wintering grounds, and human social dimensions. With due respect to my scientist colleagues involved in the first two of these working groups, the third one will be the key to the future of the Kirtland’s Warbler. Chief among its charges is “capacity building”—the modern euphemism for raising friends and funds. To this end, the remarkable Kirtland’s Warbler Alliance was formed in 2013, with the goals “to secure longterm sustainability for the Kirtland’s Warbler regardless of listing status…to eventually see the Kirtland’s Warbler graduate from protections provided by the federal Endangered Species Act…and thrive as a result of strong public–private funding and land management partnerships.”

The underlying concept of the Alliance is worth emphasizing, and emulating. The Endangered Species Act did its job—the Kirtland’s Warbler rose from the ashes of imminent extinction as a direct result of significant federal protection and funding. Now, because sustaining this ecologically specialized warbler requires perpetual investment, we must organize and generate state and private capacity to supply this investment. In my view, what makes this approach especially attractive is that it is amenable to a simple one-time solution: calculate the annual costs of the most crucial on-the-ground actions (probably cowbird trapping and jack pine management), and raise the necessary endowment to ensure that those expenses will be met forever. I am pleased to commit the Cornell Lab of Ornithology to working with the Kirtland’s Warbler Alliance to help bring this revolutionary approach to fruition.

A New Dawn for the Night Parrot

Mon, 06/12/2017 - 15:38
Night Parrots were rediscovered in 2013, a century after the last sighting of a living individual. Image courtesy of the Biodiversity Heritage Library via Creative Commons.

“Next to the discovery of a new species, there is no event so exciting as the rediscovery of a lost one,” a biologist named Hugh Wilson wrote 80 years ago in a paper about Australia’s Night Parrot. At the time, there hadn’t been a confirmed sighting of a Night Parrot in 25 years, and despite his hopeful tone, there were to be no more sightings for the rest of the century.

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Even by the standards of Australian wildlife, the Night Parrot is an odd, almost fantastical creature. It’s a bright yellow-and-green parrot with big eyes and stubby legs that creeps through the driest regions of Australia beneath a spiky, almost impenetrable kind of grass called spinifex. It only comes out under cover of darkness. And until recently, no one even knew what it sounded like.

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Night Parrots were recorded into the early 20th century, but Australia was changing. European settlement during the late 1800s brought invasive plants, predatory cats and foxes, and different fire regimes to the continent’s dry interior. Alongside many of Australia’s small desert mammals, Night Parrots drifted into extinction. Or so it seemed.

“If we had intentionally gone out and tried to make these things extinct, we couldn’t have done it better,” says Steve Murphy, a Night Parrot expert with the nonprofit Bush Heritage Australia.

Now, in just the last five years, a flurry of unexpected breakthroughs has changed the whole story. With two sightings on opposite sides of the continent, recordings of the bird’s call, a better understanding of their habitat, and even the discovery of a nest, a new view is emerging of this enigmatic bird.

Hope for the Night Parrot started to return in 1990, when a group of ornithologists stopped to bird along a remote highway in western Queensland. They happened to pull up beside a pile of feathers that turned out to be a roadkilled Night Parrot, a tantalizing confirmation that somehow, somewhere, a population endured.

Inspired by their story, a birder named John Young spent 15 years searching for that population. In 2013 his persistence paid off: he discovered Night Parrots in remote southwestern Queensland, the first living birds recorded in over a century.

Young had heard unfamiliar calls that he suspected were Night Parrots in 2008, but it still took five years before he successfully called a bird into a spotlight to get photo documentation. After his discovery, Bush Heritage Australia, state and federal governments, and scientists swung into action, protecting the location through a secret reserve known as Pullen Pullen and forming a Night Parrot Recovery Team.

Young’s audio recordings were kept under wraps to protect the few known birds, and only released in February 2017 to aid searchers in other parts of Australia (playback is still banned around Pullen Pullen). The hope was that birders equipped with the calls  would be able to find new Night Parrot locations.

In 2017, four birders found this Night Parrot in Western Australia, more than 1,000 miles away from the Queensland sightings—adding to optimism that the species still survives in the Australian outback. Photo by Nigel Jackett.

The very next month, 1,200 miles away from the Queensland site, four birders discovered a second population. “It was all very surreal,” says Nigel Jackett as he recalls flushing the first Night Parrot seen in Western Australia in over a century. For Jackett and his fellow birders, it was the culmination of a seven-year search that had begun even before Young’s discovery in Queensland.

More On Birds Coming Back From the Brink

Despite the timing, Jackett says the Queensland recordings didn’t help the group so much as confuse them. They heard strange calls, but “they didn’t really match the quality of the released calls… there’s definitely some sort of regional dialect,” he says. Instead, Jackett says their success lay in their understanding of Night Parrot ecology, pieced together from historic accounts and recent, undocumented sightings from a team led by Neil Hamilton of the Department of Parks and Wildlife in Western Australia. Their search was also aided by insights from traditional Martu landowners.

With help from Hamilton, “we figured out that what these Night Parrots are likely to live in is very old spinifex,” Jackett says. “Once we tried that, it was actually the very first place where we found them.”

Ancient spinifex hummocks—some nearly 90 years old—are uncommon in Australia. Most were eliminated by massive fires fed by years of fuel build-up from European settlers’ fire suppression, leaving barely any old spinifex to shelter Night Parrots. Cats and foxes preyed on any parrots that were left, along with many of central Australia’s native mammals.

Biologist Steve Murphy holds a male Night Parrot in Queensland, Australia, and prepares to attach a tiny GPS tag. Data on the bird's movements will help scientists learn about how this mysterious bird uses its habitat. Photo by Rachel Murphy.

“Basically, if you’re a mammal [or a Night Parrot] in central Australia about the size of a rabbit, you’re either extinct or critically endangered,” Murphy says.

Despite these pressures, Night Parrots seem to have persisted in areas that managed to resist the changes. In the so-called “Channel Country” of southwestern Queensland, bare patches of rock surround spinifex hummocks, keeping them safe from fires. In Western Australia, networks of dry salt lakes, with soil too alkaline for plants to grow, serve a similar function. Better yet for the parrot, foxes are rare in both areas.

So if their habitat didn’t completely vanish, how did two different populations go unnoticed for a century? Hamilton thinks Night Parrots and other aridland birds and mammals have rebounded thanks to long-running restoration efforts. These include work to remove introduced cats and keep out spinifex-eating cattle and camels. Add to that a stroke of luck in the form of recent heavy rains, which cause spinifex to bloom and spur the parrots to call more frequently as they scramble to begin breeding, Hamilton says.

Jackett’s team made their discovery in the remote Australian outback in Western Australia, where the population density is 300 times lower than Wyoming, the least populated U.S. state.

“Where Night Parrots live is probably a thousand kilometers from any capital city, and it’s really a hostile place,” Jackett said. “You need to be fully self-sufficient. Where we were going, if it rained, we would have been trapped there for potentially a week.” On their expedition, the group traveled with a week’s food and water, a generator, and a backup vehicle.

Now that Night Parrots been found in two widely separated places, Jackett believes the birds may live on in other remote areas. “I think they’ve just been overlooked due to lack of knowledge about their ecology,” he says. “I think figuring out this habitat, a lot more birders are going to have the confidence to look for them in the right way.”

Murphy concurs: “One of the places that always jumps out at me is northern South Australia.”

While they’re still anything but common, there’s a good chance that more Night Parrots are out there in the Australian outback, foraging by moonlight in ancient riverbeds and slumbering by day in the thick, spiny protection of spinifex.

Sarah Toner is a Biological Sciences major at Cornell University (Class of 2019) and current president of the Cornell Student Birding Club. Her work on this story was made possible by the Cornell Lab of Ornithology Science Communication Fund, with support from Jay Branegan (Cornell ’72) and Stefania Pittaluga.

Jack Pine Juggernauts: What Will Happen to Kirtland’s Warblers After Delisting?

Thu, 06/08/2017 - 15:34

Amid a sea of scrubby jack pine, several scientists gather as a male Kirtland’s Warbler—one of several within earshot—sits on the tip of a tree branch and fills the sky with his buoyant, clear song. The large warbler, with dandelion-yellow breast and slate-blue head and back, stands out as clearly as a traffic sign. It seems somehow incongruent that one of the continent’s rarest migratory birds would sing so boldly in plain view, only 30 feet away.

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“Oh, we can get way closer,” marvels Nathan Cooper, a researcher at the Smithsonian Migratory Bird Center. “They just sing. They seem to sing all the time.”

The spirited male makes no effort to hide or evade. “They just don’t know any better,” adds Peter Marra, the head of the Smithsonian center and an expert in songbird migration and population dynamics.

Kirtland's Warbler male singsMedia Player Error
Update your browser or Flash pluginA male Kirtland’s Warbler sings his spirited chip-chip-che-way-o song from the tree tops in northern Michigan. Video by Benjamin M. Clock/Macaulay Library.

The task of finding a singing Kirtland’s Warbler on its nesting ground would have been vastly harder three decades ago. At that time, the entire known population numbered only 167 breeding pairs scattered across the jack pine barrens of the northern portion of Michigan’s Lower Peninsula. But in the years since, the boisterous warbler has multiplied to more than 2,000 pairs and has spread—albeit tentatively—to Michigan’s Upper Peninsula, northern Wisconsin, and across the border to Ontario.

“I think it’s a tremendous success story,” says Marra. “Are we out of hot water? No, I would say we’re not out of hot water, especially given some of the threats that we’re seeing during the nonbreeding season, like climate change and sea level rise,” which could affect the warbler’s wintering habitat in the low-lying Caribbean.

“So it’s important that we continue to do this kind of research to really understand as much as we can about the species and to get the population size as high as we possibly can so it’s safe, not just for the next 50 years but maybe 200, 300 years.”

The success and upward trajectory of the warbler’s numbers has prompted the U.S. Fish and Wildlife Service to consider downlisting the Kirtland’s from “endangered” to “threatened” on the federal endangered species list, or removing it altogether.

But hurdles remain. And even if the path is cleared for removing endangered species protections entirely, the Kirtland’s Warbler will remain utterly dependent on continued human maintenance of its breeding habitat.

“The Kirtland’s Warbler is one of those ‘conservation-reliant’ species,” says Christie Deloria, a Fish and Wildlife Service biologist and member of the Kirtland’s recovery team who has worked with the species for more than 20 years.

“This is a species that’s going to need our attention into the future,” she says. “There are many other listed species that are in the same boat. But what’s unique maybe with Kirtland’s is that we’ve had huge success at recovering the species. And we are perhaps one of the first groups to be figuring out how do we take a conservation-reliant species off of the endangered species list.”

Kirtland’s Warbler by David Speiser. Habitat Loss and Cowbird Eggs

The Kirtland’s is jumbo  by warbler standards—up to 15 grams, about twice the size of an American Redstart. It was named for an Ohio doctor and naturalist (Jared Potter Kirtland), but sometimes it is called the “jack pine warbler,” because it habitually nests on the ground beneath young jack pines. And it is there that the long story of its decline and near-extinction begins.

From the Great Lakes to the Bahamas: This map shows a model of probable Kirtland’s Warbler residency, based on data downloaded from a geolocator tracking device. The warbler followed a looped migration route: the dashed line shows fall migration; the solid line shows spring migration. The project gathered data from 27 Kirtland’s Warblers carrying geolocators. Map from a Journal of Avian Biology paper.

Each spring Kirtland’s Warblers fly north from the Bahamas to Michigan, where they pair up and nest almost exclusively in large tracts of jack pine between 1 to 4 meters (3 to 12 feet) tall. Marra says it’s not clear why Kirtland’s Warblers will nest only among young trees. But it is clear that once the stand reaches about 15 years old, the birds disappear.

It’s also not clear if the warbler’s reliance on young jack pine evolved since the last glacial retreat about 10,000 years ago, or if the bird has followed jack pine forests at glacial margins through several ice ages. But the warbler and jack pine are inextricably linked now, and the only natural way to create sweeping stands of scraggly young jack pine is through forest fire.

In the past, fires were ignited by lightning and also by indigenous peoples to create openings for game and forest crops, such as blueberries. The Kirtland’s was probably never common, even in its Michigan range. Its numbers may have peaked in the late 1800s, when wildfires scorched the land in the wake of pine logging. By the 1920s, settlers got serious about stomping out wildfire. The amount of land in warbler territory that burned each year fell from an average of 14,000 acres (based on fire records) to only about 1,000. Jack pine grew too old and tall to interest warblers.

Vanishing habitat wasn’t the only problem. By the early 1900s, Brown-headed Cowbirds were becoming common, taking advantage of the openings created by logging and agriculture. Cowbirds lay their eggs in the nests of other birds, and the cowbird young hatch early and monopolize food. The first instance of cowbird parasitism of a Kirtland’s Warbler’s nest was reported in 1908. The warbler seemed unable to identify the intruders or remove their eggs or even defend its own young. Parasitism rates ranged from 48 to 86 percent of Kirtland’s Warbler nests, according to Fish and Wildlife researchers William Shake and James Mattsson. Kirtland’s nests on average produced fewer than a single warbler fledgling.

As fire-generated habitat disappeared and cowbirds invaded, the number of warblers plummeted. A 1951 census counted only 432 singing males in 28 townships. By 1971, the number had fallen to 201 in just 16 townships. In 1974 and again in 1987, the population hit its nadir at 167 singing males.

Trapping and removal of Brown-headed Cowbirds—a nest parasite that lays its eggs in other species’ nests—has been a key component of reducing the threats to Kirtland’s Warbler breeding success. The average output of Kirtland’s young per nest has tripled since the program began. But at a price tag of $100,000 per year, the continuation of cowbird trapping is uncertain if funding is reduced due to Kirtland’s Warbler delisting. A High-Maintenance Project Pays Off

As early as 1957,  state and federal wildlife managers began creating more jack pine stands to benefit warblers. In 1973, the Kirtland’s Warbler became one of the first species protected under the Endangered Species Act. A recovery team of federal and state biologists aimed to “reestablish a self-sustaining Kirtland’s Warbler population throughout its known range at a minimum level of 1,000 pairs.”

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Foresters created habitat through clearcutting and then prescribed burning. But the thousands of homes, cabins, and trailers tucked into the woods along dirt roads and country highways made fire a risky bet. The Mack Lake fire in 1980 forced a major rethinking in strategy.

On the morning of May 5, a district ranger on the Huron National Forest gave the okay to light a prescribed burn in southern Oscoda County. As described in a 1981 article in American Forests  magazine, relative humidity was low and the temperature, already 74, was forecast to rise during the day. Several spot fires broke out along the perimeter of the burn. Shortly after noon, fire leapt into the crowns of jack pine along Highway 33. By 12:20 p.m. the call went out that the Forest Service needed help. The fire was out of control.

Seven hours later, according to American Forests , nearly 25,000 acres were charred. Forty-four homes and cabins were damaged or destroyed. A Forest Service fire technician was dead. Local resident Joe Walker remarked as he raked through the remains of his cabin, “I hope that warbler enjoys his nest. My nest is burned.”

Mack Lake made the use of fire fraught, if not impossible. Instead, land managers developed a method of clearcutting and mechanical planting, incorporating half-acre openings among the rows of jack pine. Currently, about 4,000 acres are harvested and replanted each year, about half on state land and half on the Huron-Manistee and Hiawatha National Forests. The timber management is purely in the name of habitat—young jack pines have very little commercial value.

A cowbird trap.

Creating habitat was one thing, but keeping cowbirds away was another. In 1972, the Fish and Wildlife Service began trapping cowbirds and quickly reduced parasitism to less than 10 percent of Kirtland’s Warbler nests. The rate has continued to drop as the agency has spent roughly $100,000 a year to capture and euthanize an average of nearly 4,000 cowbirds each season in Michigan.

That two-pronged approach did the trick. By the late 1980s, Kirtland’s Warblers began to increase in number. Annual production of young has more than tripled to 3.52 young fledged per nest attempt. The species surpassed its recovery goal of 1,000 breeding pairs in 2001 and has doubled since then.

Despite this success, the Kirtland’s Warbler will continue to be a high-maintenance project—probably for as long as warblers and humans share the continent. Unlike, say, the Bald Eagle, a bird that could take care of its own recovery after humans stopped using DDT, the Kirtland’s Warbler will depend on the high-cost creation of its nesting habitat and ongoing cowbird control.

Money to maintain habitat and trap cowbirds is available through the warbler’s designation as a federally endangered species. But “when we take it off the endangered species list, that money goes away,” says Deloria, whose first job with the Fish and Wildlife Service was running the cowbird trapping program.

That’s where Marra’s research with the Smithsonian Migratory Bird Center comes in. “This study that they are doing is really important,” says Deloria. “If we could operate fewer traps on the landscape, and the program costs less to operate, maybe we don’t have to raise as much money.”

For their nests, Kirtland’s Warblers carve out shallow depressions in the sandy soil and then build open cups woven from sedges and pine needles. Linking Summer and Winter Habitats, and the Places In Between

Marra has stalked the Kirtland’s nesting grounds for several years now. In a study published in 2009, Marra and PhD student Sarah Rockwell examined isotope signatures found in the blood, feathers, and nails of Kirtland’s Warblers to determine the conditions of their wintering habitat in the Bahamas. They recorded how early the birds arrived on their nesting grounds and how many fledglings they produced. Wetter years in the Bahamas meant more fruit and insects for warblers, earlier migration, and better reproductive success 1,400 miles north in Michigan.

“To some degree, Bahamian rainfall drives reproductive success [in Michigan],” says Marra. That knowledge may become ever more critical as sea level affects the low-lying Bahamas and a changing climate affects precipitation patterns.

Lakeland University biology professor Paul Pickhardt assisted with monitoring nesting progress in the study area. Early results show it may be possible to scale back cowbird trapping and keep the Kirtland’s Warbler population growing.Scientists use nets to trap the birds before banding and fitting them with geolocator backpacks.A Kirtland's Warbler caught in a net will get fitted with geolocator backpack.Tracking data from the geolocators helped scientists identify key Kirtland’s Warbler habitat for breeding, migration, and wintering.The geolocator backpacks weigh less than 3 percent of the bird’s body weight.PreviousNext

More recently, Marra and Nathan Cooper, a postdoctoral student, fastened 0.5-gram geolocators like tiny backpacks to Kirtland’s Warblers they netted in the pines. When the birds were recaptured on the nesting grounds a year later, data stored in the tiny sensors allowed Marra and Cooper to calculate within about 120 miles the location of their wintering grounds (almost exclusively in the central Bahamas), and more important, the routes of their migration and location of their stopovers.

“We were able to identify three to five key areas during spring and fall migrations that look like they make up the really important migration stopover sites for these birds while they’re moving,” says Marra. “So this allows us to target those areas and get more and more information about birds in those spots. What are the key stopover areas? What are the key threats? It’s all ultimately going to help save the species even more than we’ve been doing now.”

On this particular morning—the summer solstice—we hike down a sandy track into the heart of a stand of young jack pine nearly a mile across, about 3 miles east of Grayling, Michigan. Most trees stand not much taller than a living room Christmas tree. As we duck into the pines, brittle lichens crunch underfoot. Among the trees,  the ground is covered by blueberries, the pale green fruit the size of BBs. In another month, the berries will be ripe for birds and black bears.

For the past several weeks Cooper has been searching jack pine stands throughout the warbler’s range for nests. He and Marra are working on a study to determine the rate of cowbird parasitism and the success of Kirtland’s nesting. They have worked with the Fish and Wildlife Service to suspend cowbird trapping in certain areas to determine whether the costly control can be scaled back without imperiling the warblers’ recovery.

“Right now we have a series of [nest] sites from right next to the cowbird traps to all the way out to 12 kilometers [7 miles] from active cowbird traps,” says Cooper. “The idea was to look at how that parasitism rate varies with distance from the nearest trap.

A Kirtland's Warbler feeds its chicksMedia Player Error
Update your browser or Flash pluginA Kirtland’s Warbler feeds its chicks. Video by Benjamin M. Clock/Macaulay Library.

“Historically, every Kirtland’s [nest] has been within a mile of a cowbird trap. But that rule has never been extensively tested. Basically we know it works, but it could be that five miles is fine or 10 miles is fine or that trapping every other year is fine. We don’t know. Now that they’ve met their recovery goal, it’s a little safer to play around with these things.”

Early in the season, Cooper and four assistants watched adult birds gather sedges and noted where they dove down to the base of a jack pine to build their nests. The task became easier as eggs hatched and the adults—warbling males in particular—made repeated food runs back to the nests.

“They’ll spend the majority of their time flying around collecting food, singing the whole time,” says Cooper. “You can actually hear the difference in their song when their mouth is full. They’re trying to do the same song but without opening their mouth and losing all the bugs.”

Cooper leads us to a nest location that has already been marked on his GPS. It’s tucked into a mound of shrubbery near the tip of a descending jack pine branch. He bends down, pulls the leaves aside, and peers in.

“Five nestlings,” he says. “They’re looking like six to seven days old. A couple more days they’ll be out of here, if they make it. Predation rates are pretty high during this phase. Just like it’s easy for us to find it, it is for everybody else.” Squirrels, chipmunks, snakes, feral cats, and Blue Jays all snack on Kirtland’s nestlings. Meanwhile, a male is chipping in a nearby tree. Says Cooper, “He’s a little [ticked] off right now.”

So far, Cooper and Marra are hopeful that cowbird trapping might be scaled back. Says Cooper, “This year we’re up to 90 nests so far and only one cowbird egg, infertile.”

Smithsonian Migratory Bird Center scientists Scott Sillett, Nathan Cooper, and Peter Marra (left to right) conducted field research in June 2016 to see how Kirtland’s Warblers responded to different management strategies. Making Progress: From Endangered to Threatened

The Fish and Wildlife Service recommended in a five-year review completed in 2012 that the Kirtland’s Warbler be downlisted from “endangered” to “threatened.” Now, the agency is poised to go even further and take the bird off the endangered species list altogether.

The recovery team officially folded its tent in March 2016 and passed responsibilities to a conservation team, says Deloria. The conservation team—which includes some of the same researchers and administrators from the earlier team—is looking for ways, in Deloria’s metaphor, to build a three-legged stool.

The first leg, largely accomplished, is securing commitments from state and federal agencies to continue creating habitat, trapping cowbirds as needed, and monitoring the recovery. Says Deloria, “We’ve got a 40-year history of working together, so we’re not basing this on nothing. We’ve all been working together for a long time.”

The second leg is funding. Agencies are committed to creating habitat, but no one has volunteered money for cowbird trapping. “The cowbird trapping program is probably one of the biggest holes,” says Deloria. That’s why Marra’s research could be such a boon if it shows a way to reduce the intensity and cost of cowbird control.

The third leg is cultivating a friends group to support the warbler. Deloria thinks they’ve found such a group in the local Kirtland’s Warbler Alliance, a volunteer group of birders and biologists. “They can help garner more support from the local communities that we’re working in,” she says.

“It’s a pretty amazing thing that’s happened with Kirtland’s Warbler when you think about it, the amount of effort that has gone into saving the species,” says Scott Hicks, field supervisor for the Fish and Wildlife Service in East Lansing, the office responsible for much of the Kirtland’s territory. “I feel good about where we’re at and the opportunity to hopefully propose to delist it in the future.”

Hicks says the agency has received funding to begin the two-year process of downlisting or delisting, which involves  writing a proposal and responding to public comments and expert opinion.

“We anticipate that the downlisting proposal will be published in the fall of 2017,” he says.

Celebrity of the Jack Pines A Kirtland’s Warbler among the jack pines. Photo by Steve Gettle/Minden Pictures.

As our little band emerges from the jack pines, a party of bird watchers parks along the dirt road and scrambles from their cars with cameras and telescopes. The Kirtland’s Warbler has become a minor celebrity in the northern Lower Peninsula. The latest Fish and Wildlife Service survey estimated that wildlife watchers spend more than $1 billion in Michigan each year. And the magazine Bird Watching  pegs the Kirtland’s Warbler as the nation’s seventh most sought-after species. Michigan Audubon runs tours out of nearby Hartwick Pines State Park, and the Forest Service offers Kirtland’s safaris out of the town of Mio.

The birders line up along the shoulder of the road. Then one spots a male Kirtland’s in the branches of a tall tree. As the warbler calls out, a ripple of excitement passes through the crowd. People adjust their optics and crane to find the distant bird in their spotting scopes and camera viewfinders.

If only they knew to relax. In just a few minutes, once they hike down the dusty path to the heart of the jack pine stand, they will no doubt find Kirtland’s Warblers all but perching on the ends of their binoculars and the brims of their floppy hats.

Greg Breining has written about nature, science, and medicine for several national publications, including the New York Times, National Geographic Traveler, and Audubon.    

Lost Birds: The Search to Rediscover Species That Might Not Yet Be Extinct

Thu, 06/08/2017 - 15:32

The song was a surprise: A succession of coos like water drops, both monotonous and musical. They sounded sleepy, familiar, and yet just foreign enough to catch ornithologist Rafael Bessa’s attention.

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It was a brilliant June afternoon in 2015, and the song fluted from some rock outcroppings near the verdant palms of a vereda, or oasis, in an expanse of shrubby grasslands in southern Brazil. The country’s Amazon rainforest has long captured conservation headlines, but the cerrado—as this mixed savanna of grass, brush, and dry forest is called—covers 20 percent of the country’s landmass, and is more threatened. Bessa himself was there in the state of Minas Gerais to conduct an environmental assessment for a proposed agricultural operation. He had stumbled on the vereda while driving from his hotel to a distant survey site. There was no time to investigate the plaintive call, but the “woo-up…woo-up…woo-up” sounded a bit faster and deeper than the Ruddy Ground-Doves that occur in abundance in the area. Bessa decided to return.

The next day, he managed to record the mysterious call and summon its maker into a nearby bush with the playback. He aimed his camera and took a series of photographs, then zoomed in on the images.

The Blue-eyed Ground-Dove was rediscovered in Brazil in 2015 after a 74-year absence from the scientific record. It was rediscovered more than 600 miles away from where it had last been seen in 1941. Photo by Rafael Bessa.

It was indeed a small dove—not necessarily the sort of quarry birders get twisted up over. Its back was an unspectacular greenish-brown, and its head, tail, and breast were a muted ruddy orange, blending to a creamy belly and a set of bony pink feet. But its eyes were arresting pools of spectacular cobalt blue, echoed by little half moons of the same dabbed across its wings.

Bessa’s hands began to shake. “I had no doubt that I found something really special,” he says.

Seeking confirmation, he texted his friend Luciano Lima, the technical coordinator at the Observatório de Aves of the Instituto Butantan, São Paulo’s biological and health research center. Lima had done his master’s degree in a museum with an extensive specimen collection, and agreed to drive to his office to pull up the photos on his computer and see if he could identify the mystery dove.

“I was in my car,” Lima recalls, “and he suddenly sent me one of the pictures, and I almost crashed!”

Lima called Bessa back from the institute: “‘Hey man, you found the bird! You found the bird!’ I remember repeating it to him like a thousand times.”

Bessa had discovered a pocket refuge of Columbina cyanopis, the Blue-eyed Ground-Dove. The creature was exceedingly rare; some suspected it was extinct. Though there had been a few published sightings over the past couple of decades, it hadn’t been documented with hard evidence in 74 years. And Bessa had taken the first-ever photos and recordings of the bird some 600 miles away from the nearest place specimens had been collected.

“There is thousands and thousands, and hundreds of thousands, and millions of thousands of hectares, and he just managed to be in the exactly right place,” Lima marvels.

When Lima himself went out to see the bird a year later, after the rediscovery was announced, he was overcome.

“I don’t have words to describe it,” he says. “It’s like seeing a ghost.”

Three Lost Birds: The American Bird Conservancy’s Lost Birds of the Americas project is mounting expeditions in hopes of rediscovering the Kinglet Calyptura in Brazil, the Turquoise-throated Puffleg in Ecuador, and the Táchira Antpitta in Venezuela (left to right). Images by William Swainson, John Gould, and Handbook of the Birds of the World Alive, Lynx Edicions. Lazarus Species

The reappearance of such ghost species isn’t as unusual as you might think. According to a 2011 review in the journal PLOS ONE, some 144 bird species have been “rediscovered” over the last 122 years, the vast majority of them after 1980. In 1984, ornithologist Dick Watling stumbled on the “extinct” Fiji Petrel after years of searching when a juvenile flew into his head one rainy night.

“A more undignified return to human awareness after 129 years of peaceful oblivion could not be imagined,” Watling later wrote.

In a recent wave of finds, researchers turned up the Banggai Crow, not seen since 1900, in Indonesia in 2007; the Jerdon’s Babbler, undocumented since 1941, in Myanmar in 2014; and, the Blue-bearded Helmetcrest hummingbird in Colombia in 2015, after a 70-year absence.

Against the backdrop of a human-caused sixth mass extinction, it’s tempting to regard such tales as glimmers of light in a dark time. Just as there is a recently coined term for the last individual of a species—an endling—so too is there a much older phrase for those that reemerge—a Lazarus taxon, named after the man Jesus brings back from the dead in the Bible.

The Cherry-throated Tanager was rediscovered in Brazil in 1998. Photo by Ciro Albano.

Still, rediscoveries say less about miraculous recovery than they do about our limited knowledge of a world we are reshaping at a breakneck pace. As Paul Donald, Nigel Collar, Stuart Marsden, and Deborah Pain wrote in their 2013 book, Facing Extinction, nearly all birds “begin their taxonomic lives—their epistemological existences—as rarities,” known only from one location and a specimen or two. It’s only with consistent attention and study that a more complete picture of a species emerges—where it lives, what it needs, how numerous it is. Even today, though birds are some of the best-studied creatures on Earth, many species remain “inveterate skulkers in the historical undergrowth.”

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The 2011 PLOS review found that 40 percent of rediscovered bird species were known only from the original type specimens that led to the first formal description of the species, decades to centuries ago. Some may have been hard to refind because their collector hadn’t noted basic details about the location of capture, let alone life history and habitat requirements. Others may not have been resurveyed or confirmed because they were remote and had secretive habits that made them difficult to track. Or people simply may have not been searching for them. Some were locked away in conflict zones where it was dangerous to search. For example, the Táchira Antpitta—a leggy, quail-sized bird known only from four specimens collected 60 years ago—has been difficult to reconfirm because it was initially found in cloud forests on the Venezuela-Colombia border, an area rife with guerrilla activity and drug trafficking.

As the number of searchers and searches has increased—with more taxonomists, bird watchers, ecotourists, and expeditions—so too has the number of rediscoveries climbed, particularly in the tropics where there are vastly more species. Ironically, increasing incursion into and development of wild places has probably also fed the trend.

“If a bird has not been seen in North America or Europe for several decades, then it’s a safe bet that it just isn’t around anymore. Too many people looking, too few places to hide,” explains Neotropical bird expert Tom Schulenberg, a research associate at the Cornell Lab of Ornithology. But “countries in the tropics tend to have less in the way of infrastructure. Fewer roads, fewer scientific institutions, fewer biologists, less money to throw around on pursuits such as searching for lost species.” That leaves more yet to discover—and rediscover.

If a “lost” bird species has made it long enough to be rediscovered, there is the hope of helping them eke out an existence for a little longer.~Tom Schulenberg

For hard-to-find creatures, the difference between steep population decline and actual extinction is a murky one. Often rediscoveries simply reveal that a rare species is getting rarer. Some 86 percent of birds described in the PLOS paper remained highly threatened when they reappeared on the scientific radar, many for decades afterward.

Still, reemergence is also evidence of resilience, and a chance at some kind of redemption. A small population makes a species more vulnerable to random destructive events and inbreeding, but it’s not necessarily a death sentence. Biologists have successfully used interventions such as nest protection and captive breeding to bring California Condors back from 22 individuals in 1981 to more than 200 in the wild in 2014, and Mauritius Kestrels from the last four of their kind in 1974 to a wild population of around 400 in 2012.

If a “lost” bird species has made it long enough to be rediscovered, Schulenberg says, “there is the hope of helping them eke out an existence for a little longer.”

To search for the Turquoise-throated Puffleg, the American Bird Conservancy and its Ecuadorian partner Fundación Jocotoco are sending researchers into the Río Piganta region in the Andes Mountains. The species was last seen in 1976. Photo courtesy of Juan Freile. Hunting for Ghosts

That hope is what Daniel Lebbin, vice president of international programs at the American Bird Conservancy, had in mind when he cooked up the organization’s Lost Birds of the Americas project about three years ago. Combing over the International Union for Conservation of Nature’s Red List of Threatened Species, Lebbin made note of some 24 birds that were listed as critically endangered, but hadn’t been seen in the wild for a long time. Then, he eliminated some species that had already been searched for unsuccessfully, and island endemics that had likely been devoured out of existence by invasive species such as rats or killed off by exotic disease. In the end, he was left with just a few continental species whose potentially larger ranges left more room for holdouts.

Chestnut-bellied Flowerpiercer
Last Seen: 1965 — Found: 2003
A small tanager found at higher elevations in a few locales in Colombia. Flowerpiercers feed on nectar by piercing the bases of flowers. Photo by Ciro Albano.Dusky Starfrontlet
Last Seen: 1951 — Found: 2004
Deforestation and mineral extraction threaten the incredibly small range of this bird in northwestern Colombia. Photo by Nigel Voaden/Macaulay Library.Biet's Laughingthrush
Last Seen: 1989 – Found: 2008
Scattered populations in Yunnan and Sichuan provinces in China are small and declining due to habitat loss. Photo by Alister Benn.Rusty-throated Wren-Babbler
Last Seen: 1947 - Found: 2004

A tiny, vocal songbird in the Mishmi Hills in northeast India. Photo by Claudio Koller.Kaempfer's Woodpecker
Last Seen: 1926 — Found: 2006

A bamboo specialist with populations that are uncommon despite its broad range in eastern Brazil. Photo by Ciro Albano. Recurve-billed Bushbird
Last Seen: 1965 — Found: 2004

A remarkable-looking antbird from Venezuela with a bizarrely large, wedge-shaped and upturned bill. Photo by Chris Sharpe.Cone-billed Tanager
Last Seen: 1938 — Found: 2003

Currently known only from two sites in central Brazil, but additional populations may be discovered as more fieldwork is conducted. Photo by Bertrando Campos.Yellow-eared Parrot
Last Seen: 1919 – Found: 2005
Large, nomadic species that nests in wax palms in western Colombia and possibly northern Ecuador. Photo by Felix Uribe.PreviousNext

There was the Turquoise-throated Puffleg—an Ecuadorian hummingbird with colors as flamboyant as its name, collected in 1850, with an unconfirmed sighting in 1976. There was Brazil’s Kinglet Calyptura, which had vanished for 119 years before a brief dip back into scientific consciousness in 1996. And there was the Táchira Antpitta, the enigmatic species that had vanished into a zone of guerrilla conflict that now seems to have quieted a bit.

“Not much is going to happen conservation-wise for these birds unless you know where they are,” Lebbin says. And with habitat destruction proceeding apace, not looking for them raises the prospect of what some biologists have called the Romeo Error: In Shakespeare’s classic play, Romeo ensures Juliet’s death by believing, wrongly, that she is already dead.

Lost Birds expeditions have been carried out and are continuing by South American partner organizations with ABC’s funding, but none have yet resulted in published, peer-reviewed finds. And even if they do, more study will likely be needed to help the birds.

“If we don’t know how many, or what’s the habitat of the [lost] bird, or the behavior of the bird, then not much can be really done to preserve it,” points out Jhonathan Miranda, a Venezuelan university student who works for the nonprofit group Provita and has led the ground search for the antpitta.

Those are exactly the sorts of information gaps that researchers have been working to fill for Brazil’s Blue-eyed Ground-Dove. With funding from Rainforest Trust, the conservation organization SAVE Brasil set out to assess whether the bird was under imminent threat. Fortunately, the corner of cerrado where it lived turned out to be too rocky for farms, says SAVE Brasil Executive Director Pedro Develey, “so we have a little time.”

Researchers have used that time to identify other suitable Blue-eyed Ground-Dove habitat, with the help of computer models and satellite images. Early surveys of new sites have so far come up empty, but about a dozen Blue-eyed Ground-Doves have turned up in the general area around Bessa’s 2015 discovery. And in April, a graduate student named Bruno Rennó began a field project studying the rediscovered population, with the support of Fundação Grupo Boticário, SAVE Brasil, and others. Over the next year, he hopes to nail down some basics about the doves’ lives and habits.

Meanwhile, SAVE Brasil and Rainforest Trust have raised much of the money necessary to buy the 640 hectares where the Blue-eyed Ground-Dove was rediscovered as a private reserve. The find also generated momentum for a pre-existing community-supported proposal for a nearby 30,000-hectare public reserve.

Whether those considerable achievements will be enough to help the species, though, will depend on what Rennó and others actually find out about the cobalt-eyed doves. As Schulenberg points out: “A lot of ground-doves are semi-nomadic. If it’s tracking some resource, some plant that seeds only at particular seasons in particular places,” then the species may need a larger landscape to roam across than the reserve actually covers. “If it’s literally 12 to 15 birds left,” Schulenberg says, “the prognosis in the wild is terrible.”

Develey is hopeful that bird watchers will turn up more doves, and that the private reserve will be formally established by the end of this year. But not all habitat protection efforts for Lazarus birds go as smoothly. SAVE Brasil has been working with local government officials for more than 10 years without resolution to secure a public reserve for the spectacular Cherry-throated Tanager, rediscovered in the country’s heavily cut Atlantic forests in 1998. Political turnover, local opposition, and lack of resources have all been obstacles to government protection, Develey says, though a local company is completing a 1,500-hectare private reserve. And even now, scientists still know next to nothing about the bird. It lives high in the canopy, which makes it difficult to study. And it may number fewer than 40 individuals, making it hard to know whether the current conservation strategy is working.

The Kinglet Calyptura expedition project produced this wanted poster to inform the public about the search for one of Brazil’s lost birds.

Still, Lima, who is working on the so-far-unsuccessful Kinglet Calyptura search with the help of ABC funding, is optimistic about the bigger picture.

“Finding the bird is just one of the results of the project,” he says, pointing to a major Brazilian television network’s recent segment on the species. “Imagine that no one ever heard about Kinglet Calyptura, and then, after a Saturday 10-minute program, millions of people in Brazil know what a Kinglet Calyptura is, and how the bird is going extinct because people destroy the environment.

“We’re trying to make these birds visible,” he says, because people won’t value something if they don’t even know it exists.

As an Observatório de Aves hashtag campaign puts it, #esqueceréextinguir.

Forgetting is extinction, too.

Sarah Gilman is a freelance writer based in Oregon. Her work has appeared in High Country News, where she is a contributing editor, as well as Nationalgeographic.com and Audubon.org.

Two Tips for Telling a Bird’s Age by Its Molt Patterns

Thu, 06/08/2017 - 15:27

Late summer is the time when ragged, disheveled-looking birds start showing up at feeders. Gone is the sleek, clean look of spring. Some birds may even be missing feathers, as if they’ve come out the other end of a bar fight.

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These birds aren’t sick—they’re molting. Feathers are the defining characteristic for birds, and critically important for everything from attracting mates, to keeping warm, to escaping predators. But they don’t last forever, and most feathers wear significantly over the course of a year. Breeding season can be particularly rough, because of the frenetic activity and increased abrasion from dozens of visits to well-hidden nests in dense brush or cavities.

By late summer feathers are often at their worst, but fortunately food resources—insects and seeds—are abundant. So there is plenty of energy around for birds to put into growing new feathers. After chicks have fledged and before it’s time to leave for migration, most adult birds take the opportunity to replace those worn feathers. The chicks, on the other hand, are fresh out of the nest, so their molt schedule is slightly different.

Knowing a bit about what birds look like during the molt can be very useful information. In birding circles, molt has a reputation as an advanced skill. But if you arm yourself with just a couple of basic ideas, they can reveal fascinating secrets about the birds you see.

Two-toned Towhees

Take a towhee, for instance—Eastern or Spotted, depending on which side of the continent you live on. A young towhee just out of the nest looks almost nothing like the dapper black-and-white adult males. Juveniles are brown and streaky, showing the towhee’s sparrow heritage, the better to stay hidden from threats while the young birds learn the ropes.

By fall these birds will have replaced those streaky body feathers with the more traditional towhee pattern: shiny black on the head and back (brown in females), with chestnut flanks and a white belly. But young birds molt only the body feathers, not the flight feathers in the wings and tail, because flight feathers need to be sturdy and so take more energy to replace. First-year towhees won’t replace their brownish flight feathers until the next fall.

So if you ever see a towhee hopping around your feeder with two-toned wings—nice black or rich brown scapulars and wing coverts; dingy brown primaries, secondaries, and tail—you can be sure that bird is a youngster that just hatched that past summer.

This adult Eastern Towhee has glossy black wing feathers that match the color of the back feathers, scapulars, and coverts. Photo by Ryan Schain/Macaulay Library, June, Massachusetts.This immature Eastern Towhee has molted into glossy black plumage on its upperparts. But take a close look at the primary feathers (forming the wingtip): they're worn and brown. This immature won't grow new, black wing feathers until the fall. Photo by Earl Orf, January, Florida.

American Goldfinches also show a difference between adult and young birds due to molting. For example, male American Goldfinches all look shiny yellow in summer, but if you see one with faded brown-black primaries, you know it’s a bird that just hatched the previous year. It looks a little like a person wearing a new suit and worn-out shoes. And once you can spot this pattern in towhees and goldfinches, you can look for it in other species, too.

Molt Limits: Mind the Gap

In its second year, a young bird will finally replace its first flight feathers.  That’s a good time to check out its wings. Look for a pattern of worn old and pristine new feathers located right next to each other. This is called the “molt limit,” so named because it shows how far the bird has progressed in molting.  It can be visible in adult birds, but is easiest to see in the second year.

Larger birds have larger feathers, which make them great subjects for looking at molt limits. While smaller birds squeeze in their molt between the end of breeding and the beginning of migration, larger birds don’t have that luxury. Feathers can only grow so fast, so larger birds often show evidence of molt for more of the year.

This condition allows birders to easily distinguish young birds from older ones. Take the Turkey Vulture, which can live for 16 years or more. Juveniles and adults look nearly identical, but adults nearly always show obvious signs of molt in the warmer months. It takes a Turkey Vulture over one year to grow its foot-long flight feathers, one by one. While adult Turkey Vultures are molting, their older flight feathers are tattered and abraded, and there are noticeable gaps in the wings where new feathers are growing, not unlike the toothy smile of a first grader. On the other hand, young Turkey Vultures recently out of the nest will show a pristine profile with brand new feathers all in good condition and giving an even outline to the wing. It’s a distinction that is obvious even when birds are soaring at great distances.

And it works for most large birds, not just Turkey Vultures: try it out with your local Red-tailed Hawks, pelicans, and cormorants. In fact, in the early 1980s this technique was instrumental in determining exactly how many California Condors remained in the wild.

This adult Turkey Vulture has lighter and darker feathers in its wings and tail—the lighter feathers are old and worn; the darker feathers are newer. A few shorter secondary feathers create a gap in the wing, indicating molting feathers that are still growing in. Molt patterns like these tend to appear in both wings symmetrically. Photo by Brian Sullivan, August, California.This immature Turkey Vulture has uniformly colored, fresh feathers that create an even outline in the wing. Photo by Brian Sullivan, August, California.

These two patterns are just the beginning of what molt can reveal about a bird. Some scientists have used molt patterns to understand whether a bird is a long- or short-distance migrant, or even as clues to when and where a bird breeds. So take a second look at those worn feathers. There’s a lot to be learned even when birds are not at their best.

Nate Swick is social media manager for the American Birding Association and hosts the ABA’s American Birding podcast. He lives in Greensboro, North Carolina.  

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