Research Highlights from 2,000 Ornithologists at the NAOC 2016 Meeting
By Miyoko Chu, Gustave Axelson, Charles Eldermire, and Hugh Powell
August 18, 2016
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The final day of the conference kicked off with the somewhat checkered history of the study of sexual selection, summarized by plenary speaker Mike Webster of the Cornell Lab. Charles Darwin proposed the idea of sexual selection alongside natural selection, Webster said, but the prudish Victorian culture frowned on the idea of females having free will in selecting their mates, and the idea languished.
Social mores aside, Darwin was right, and so-called “female choice” is now recognized as a powerful force in evolution. Webster illustrated just a few of countless examples, showing how, over time, females’ decisions have affected the behavior and plumage of males. For example, male Black-throated Blue Warblers have become stay-at-home dads and Red-backed Fairywrens developed brilliantly scarlet display feathers as a sign of their aggressiveness. Each time a female chooses a male to mate with, his traits are passed along to the next generation—meaning that the beautiful, at times outlandish features we see in the natural world are the echoes of females’ choices in eons past.
After Webster closed his remarks, some 2,000 bipedal primates emerged into the hallways of the Hilton to attend one last day of talks and discussion. Here are just a few of the stories that caught our eye:
Hovering Hummingbirds Get Hot—Maybe Too Hot. Hovering is hard work, and as anyone with a down jacket knows, feathers are great insulation. So how does a hard-working hummingbird keep from boiling over? Infrared video shows most of the heat leaves via bare skin: around the eyes, under the wings, and in the feet, according to Don Powers of George Fox University. The catch: when the air warms above the hummingbird’s temperature, those areas start to absorb heat, making the hummer’s problems worse. In very hot regions, hummingbirds may have to take longer breaks during the heat of the day, possibly threatening their ability to feed.
Bird Cams Reveal Hard-Working Hawk Family: Big Red and Ezra, the Red-tailed Hawks whose nest is live-streamed on our Bird Cams, make up to 230 food deliveries each year, carrying roughly 88–100 pounds of food to their three nestlings. Prey varies over time, but chipmunks, Rock Pigeons, and squirrels top the menu. With millions of viewers to help log each and every prey delivery, this prey record is by far the most detailed and complete ever compiled for a wild raptor, reported Bird Cams leader Charles Eldermire.
How Do You Pack 2,000 Swifts Into a 3-Foot-Wide Chimney in 5 Minutes? To study a swirling mob of Chimney Swifts at dusk, Dennis Evangelista of the Naval Research Lab traced the path of every single swift. (It was fairly straightforward, he said, except you do need a supercomputer.) The resulting 3-D model showed that individual swifts often sync up with a few others, traveling in formation for a few revolutions of the circle as the overall flock changes shape. The model also allowed him to create a swift’s-eye view of the circling flock. (When the slide projector went on the blink, Evangelista got style points for inviting the audience to the front of the room and giving his entire talk on an iPad Mini.)
Good News for Feeder Birds: Each year, 50 million people in North America buy 1 million tons of bird food. After surveying data for 136 species, Project FeederWatch leader Emma Greig found that most feeder birds have strong populations. The flip side is that the species most in trouble—such as seabirds and shorebirds—don’t come to feeders and are declining because of other threats. Greig’s conclusion: Feeding birds may not help the hardest-hit species, but it may inspire people to support conservation, too.
Wish List for Conserving Migratory Birds: This conference celebrated the 100th anniversary of the Migratory Bird Treaty Act, and today a panel of leaders looked ahead to the next century of conservation. Here are four main themes we should work toward, they said:
- Bring together social and natural sciences. So many of our conservation challenges hinge on human behavior, more so than bird behavior, said Ashley Dayer of Virginia Tech.
- Make conservation part of the entire landscape. Parks and other protected land will never be more than 15% of the landscape, said Charles Francis of Environment and Climate Change Canada. If we want to keep common birds common, we need make all types of land work for birds.
- Conserve them wherever they go. To conserve migratory birds means working with people in Central and South America, too, said Greg Butcher of the U.S. Forest Service. The bonus: bird conservation goes hand in hand with alleviating poverty for humans.
- Widen the reach of citizen science. Tapping the help and commitment of bird watchers creates data useful not just to scientists, but to the people themselves. They can use that data to guide public decisions in their communities, said Humberto Berlanga of Mexico’s CONABIO agency. Here are 9 examples of how eBird data helped make conservation happen.
One of the great things about a conference is the chance to spot your heroes. Yesterday, the great birder Kenn Kaufman stood at a podium (looking almost like a kingbird at a perch) where he was leading a symposium on birders and conservation. Today the gifted artist and field guide author David Sibley could be seen squeezing between rows of chairs on his way between talks, looking very much like the rest of us.
With so many bird experts around, it was only a matter of time before someone started birding. In fact, the hotel now boasts its own eBird Hotspot. After three days, (and without any checklists from Kaufman or Sibley yet) the total hotel list is up to 37 species including Bald Eagle, Double-crested Cormorant, and Indigo Bunting. Not bad for downtown Washington, D.C.
The Cornell Lab has four writers roving two floors of the Washington Hilton conference center and learning as much as we can possibly cram into our brains. Here are just a handful of the fascinating stories we ran across today:
Flycatchers May See in Slow Motion: One day while peering through a microscope at an Acadian Flycatcher’s eyes, Luke Tyrrell of Purdue University saw something he didn’t recognize: hefty (though tiny) orange triangles on the retina. They didn’t resemble anything ever described in the bird world, despite all that’s known about bird vision. After much searching, he found the structures likely help flycatchers filter distracting background colors to detect tiny motions (like buzzing insects). At the same time, the structures seem to shunt extra energy to retinal cells, possibly allowing them to see the action in fraction-of-a-second intervals.
Pop-Up Artist Turns Scientists Into “BioSketches.” What do you study? Where do you study it? What do you like about it? Science writer, artist, field biologist (and All About Birds contributor) Abby McBride collars conference attendees and asks these sorts of questions. When the startled scientists answer, she makes a quick, colorful sketch on a dry-erase board and then snaps a photo of the scientist and his/her “biosketch.” The result is a moving portrait of the conference itself and all its faces—see some examples at right.
Mistaken Identities Lead to Pointless Warbler Fights: In the Appalachians, Golden-winged and Chestnut-sided Warblers nest in different places and eat different foods, but for some reason the males fight all the time anyway. Using model birds to investigate the source of the ill will, John Jones of Tulane found the birds seem to be confused by the gold crown that both species share. These fight-happy warblers would do well to brush up on their bird ID skills, it seems—as fighting a nonthreatening species is energy wasted during the crucial breeding season.
Don’t Do What I Did: Crows seem to pay attention to their dead, often gathering to scold or mob fallen crows they find. A closer look by Kaeli Swift at the University of Washington suggests they pay the closest attention to their elders. Up to two times as many crows gathered around dead adults than dead juvenile birds, especially in fall and winter. Swift suggested that checking out an adult’s misfortune might help a young, naïve bird learn about risks in its surroundings.
Goodbye Tree Climb, Hello Drone: Ornithologists rappel down cliffs, climb up trees, and more to study inaccessible birds—but maybe they no longer have to. David Bird of McGill University led a symposium on the new possibilities of science by drone, including studies counting Osprey eggs, monitoring Common Tern colonies, automatically classifying penguin nests, getting birds-eye views of Least Bittern habitats, finding hidden Bobolink nests using infrared, and even conducting birdsong surveys from up in the sky.
Flickers Only Drill When They Have To: Woodpeckers typically excavate a new nest hole each year, but Northern Flickers not so much. In fact, a full two-thirds of flickers at Karen Wiebe’s long-term study site in British Columbia never excavated a nest in their entire lifetime. And over 7 years, less than a quarter of 1,800 flicker nests were placed in freshly excavated holes. Most of those happened after fires or other disturbance destroyed existing holes. In other words, flickers are reluctant cavity excavators, going to work only when there’s a housing shortage.
Banned Chemical Shows Up in Condor Eggs: Along California’s Big Sur coast, free-flying California Condors once again scavenge for dead sea lions as they did centuries ago—but their eggs show thin shells and signs of contamination by the infamous pesticide DDT. Joe Burnett from the Ventana Wildlife Society explained that the condors most likely picked it up by eating sea lions still affected by DDT dumped in the ocean four decades ago. Read more about this detective work. The good news: 260 condors live in the wild today, up from just 27 captive birds in 1987.
Last night, a thunderstorm of operatic proportions knocked over newspaper kiosks and flooded the streets. Lightning bolts doubled and quadrupled themselves in skyscraper windows. For a tense half-hour it seemed as if D.C. might be hosting a meeting of valkyries. But in the light of morning it was indeed scientists and not mythological warriors that flooded into the plenary room for Day Two of the North American Ornithological Conference.
Here are a few of the stories we found today:
Surprise Warbler Finding Packs the House: Listeners crowded five people deep at the doors and pushed in, rock-concert style, to hear details about the incredibly similar DNA of Golden-winged and Blue-winged Warblers. Cornell Lab researcher David Toews and his collaborators found the two species are 99.97% alike genetically and might be the same species.
Endangered Falcons Become Vineyard Vigilantes: In New Zealand’s wine country, introduced birds like the Song Thrush and European Blackbird are serious pests of grapes. Recently, Sara Kross of University of California, Davis, studied the reintroduction of the New Zealand Falcon, or karearea, to the region. It has been good for birds and winemakers alike. With the looming prospect of death by falcon, grape damage dropped by as much as 95% in vineyards—a pest control savings of up to $330 per acre.
Like Bug Spray, But With Feathers: Australia grows 40,000 tons of macadamia nuts per year, and at least part of that bumper crop has birds to thank for it. Eduardo Crisol-Martinez of Central Queensland University found 65 bird species living in macadamia orchards. Some 78% eat insects, including the green vegetable bug and other known pests. Common birds like the Eastern Yellow-Robin and Lewin’s Honeyeater positively wolf the bugs down, providing a pesticide-like service for free—all we have to do is let them.
DNA Shows Woodpecker–Fungus Connection. By swabbing the bills and wings of Acorn Woodpeckers, Michelle Jusino of the U.S. Forest Service found the DNA of more than 1,000 kinds of fungi—including 300 on a single bird. By also testing trees, she discovered the most prevalent fungi tended to occur on trees with woodpecker holes rather than intact trees, possibly showing the woodpeckers seek out decayed trees because the soft wood is easier to excavate.
Bird Conservation in a Cup of Coffee…With Cream: A Nicaragua farm that grows Smithsonian certified Bird-Friendly coffee harbored more than 25 species of North American migrants in a wintertime study sponsored by Birds & Beans coffee. Meanwhile, on an Organic Valley dairy farm in Minnesota, surveys found more than 50 bird species, including several migrant species, according to Tom Will of the U.S. Fish and Wildlife Service. Baltimore Orioles were found in both places—tying not just a continent together but also the coffee and cream you put in your cup.
Eyes In The Sky Show Where Birds Go. New technology allows researchers to place tiny tags on birds and then automatically identify them whenever the birds pass within range of a receiving station—often a high tower. In a fast-paced “lightning symposium,” 13 researchers had just 5 minutes each to share what these tags revealed, including that Bank Swallows sometimes leave their nests to roost communally in wetlands, and that migrating American Redstarts and Yellow-rumped Warblers fly at the same speed (around 22 mph), but redstarts stop more often along the way.
Foresight Repaid: How much has California’s bird life changed in the last century? We’d have no way to know for certain if not for the great naturalist Joseph Grinnell, who in 1911 made detailed surveys as his gift for the future. Now, UC Berkeley graduate student Sarah Maclean has resurveyed 45 of the same Central Valley spots. Despite wetland loss and widespread development, on average the sites support more species now than then, including Great-tailed Grackle, Eurasian Collared-Dove, and others.
It’s the end of Day One of the North American Ornithological Conference here in Washington, D.C. There are 2,028 scientists here from more than 40 countries, and they’ve already delivered more than 250 talks just today.
It all started with Dr. Jessica Meir‘s inspiring story of her career as an ornithologist and then astronaut. Her life so far has included scuba diving with Emperor Penguins, flying Bar-headed Geese alongside her bike, becoming a Harvard professor, flying fighter jets, learning Russian, and figuring out how to drink water in zero gravity. Remember to always broaden your perspective, she said, as she turned us loose into the hallways and meeting rooms.
Here are a few of the stories we found today:
Life as an Urban Cardinal: City living has affected basic traits of Northern Cardinals, according to the Cornell Lab’s Conservation Science director, Amanda Rodewald. In urban Ohio, cardinals start nesting earlier (taking advantage of warmer temps and earlier leaf-out), have narrower bills (perhaps for eating smaller city seeds), and sing longer, faster, higher pitched songs (to be heard above city noise). It seems to be working. Many early nests in the city failed, but the cardinals had time to nest again, making up for their losses.
Follow the Eagles Home, and Save Them: Using GPS tracking data from the New Jersey Division of Fish and Wildlife, biologist Cristina Frank of energy company Pepco found 80 Bald Eagle roost sites (55 of them new to the Bald Eagle Roost Database). She evaluated the collision risk that nearby power lines posed to the eagles, using specialized “bird flight diverters” to mitigate the greatest risks. As eagle and Osprey populations continue to rebound, collaborative mapping efforts like these between industry, government, and scientists could be key to keeping them safe.
A Cool Refuge in the Canadian Maritimes: As climate change alters habitats, North America’s 3 to 5 billion boreal birds may wind up strapped for options, reported Diana Stralberg of the University of Alberta. She used models from the Boreal Avian Modeling Project to find out which species will be able to keep pace with shifting habitats. The moist, cool Maritimes may offer refuge for as many as 53 boreal species by the year 2100—key information for conservation planners.
It’s More Spectacular From a Female’s Point of View: In New Guinea’s birds-of-paradise species, the males dazzle the females with brilliant colors, fancy plumes, and outrageous dances. They also tweak the vegetation so that females have to watch from the perfect angle. But no one knew quite what the females could see, until Ed Scholes of the Cornell Lab and colleagues filmed the males from exactly that angle and made 3D models of the lighting conditions. They found that all those fancy male traits combine to give females an even more stunning view than a casual observer has.
Wood Thrushes Go Tropical in Winter: With the help of miniature GPS locators, Calandra Stanley from the Smithsonian Migratory Bird Center is learning exactly where Wood Thrushes migrate to. It seems different Wood Thrushes use different strategies to survive the winter. About half the birds she tracked to Belize moved up to 12 miles during the winter; the other half were stay-at-homes and moved no more than a football field away from where they landed after their 2,000 mile migration journeys.
Godwits Get Sandblasted on Migration: Black-tailed Godwits are a sharply declining species, and the worst part of their year might be their migration between Africa and northern Europe, reports Nathan Senner of the University of Montana. Senner found that in two years, the birds’ spring passage across northern Africa put them in the path of massive sandstorms that blow across the Sahara Desert—storms so strong that they can blow sand all the way across the Atlantic Ocean to the Amazon.
Small Changes Rapidly Create New Species: In parts of South America, 6 species of seedeaters can live in one field. Males look and sound very different, but most females can’t even be separated in the hand. Even their DNA is almost identical, said Leonardo Campagna of the Cornell Lab. All except for a very few regions, which show rapid change and turn out to code for aspects of male plumage color—suggesting one species can rapidly become many by altering just a few details in one sex.