All About Birds Blog

Home Page


A White-breasted Nuthatch in its characteristic upside-down stance. Photo by Brian Kushner via Birdshare.

Of all the regulars at your bird feeder in winter, nuthatches are the ones that are just a tad quirky. They move differently than other birds, scaling the trunks of nearby trees up, down, and sideways with the erratic motion of a wind-up toy. They also sound different, giving a funny little nasal nyuk-nyuk-nyuk or peeping or squeaking. And they look different, sort of plump with a straight, sharp bill.

Winter is the perfect time to observe how nuthatches earned their common name, as they jam large seeds and nuts into tree bark before whacking them with their sharp bill to hatch out the seed from the inside.

Nuthatches are also into caching, meaning they store food to eat later. They often store seeds, one at a time, under the loose bark of a tree, typically hiding their cache with a piece of bark, lichen, moss, or snow. Scientists have observed nuthatches retrieving and eating more cached seeds when the weather gets colder, meaning they may use caching as a strategy for keeping a ready food supply throughout winter.

In North America there are four species of nuthatch; each one using a slightly different suite of behaviors to make it through the cold winter months. Match the species to the map, and let us know if you’ve seen any of these behaviors near you:


North America is home to four species of nuthatch, each with special strategies to survive cold winter months.

White-breasted Nuthatch (Sitta carolinensis): In winter, White-breasted Nuthatches survive by staying in mixed flocks and using caching to have a steady supply of food. These birds join foraging flocks led by chickadees or titmice, perhaps partly because more eyes in a group make food easier to find and predators easier to spot. The winter feeder watcher may notice that male White-breasted Nuthatches can be rude, by human standards, pushing females aside at a platform full of bird seed. And nuthatches may steal from each others’ caches, so they tend to fly off in opposite directions from a feeder to avoid leading an onlooking bird to their secret stashes of seeds.

Red-breasted Nuthatch (Sitta canadensis): Red-breasted Nuthatches live in the North Woods and mountain forests of the West, where their excitable yank-yank calls sound like tiny tin horns being honked in the treetops. These little birds survive the cold months by migrating to areas with a more reliable winter food supply. Red-breasted Nuthatches at the northern end of their range in Canada migrate south every year, though southern populations don’t move unless the conifer seed crop is poor. When that happens, large numbers of Red-breasted Nuthatches can irrupt as far south as the Gulf Coast.

Brown-headed Nuthatch (Sitta pusilla): One of the few birds found almost exclusively in the United States, the Brown-headed Nuthatch lives in the pine forests of the southeastern states (with another small isolated population in the Bahamas). Like other nuthatches, Brown-headed Nuthatches may rely on caches of food for the winter, but they also have another trick up their sleeve: they are one of the few birds that use tools, utilizing a piece of bark as a lever to pry up the bark on a tree and look for food. Their tools give them access to additional sources of food in the winter, and they may carry their bark tool from tree to tree and also use it to cover up a seed cache.

Pygmy Nuthatch (Sitta pygmaea): Small even by nuthatch standards, Pygmy Nuthatches are tiny bundles of hyperactive energy that climb up and down ponderosa pines in the West, all the while squeaking like a rubber ducky. They are highly social and use their sociability to get them through the winter. During the cold months, they pile into a hole in a tree and roost communally; as many as 100 may share a roost. Pygmy Nuthatches survive cold nights by huddling together and going into torpor, letting their body temperature drop into hypothermia in order to conserve energy. They are the only birds in North America that combine these three energy-saving mechanisms (roosting in tree cavities, huddling together, and torpor) into one winter-survival strategy.


From left: White-breasted Nuthatch by Bill Thompson, Red-breasted Nuthatch by Kirchmeier, Brown-headed Nuthatch by Andrew Jordan, Pygmy Nuthatch by Bob Gunderson, all via Birdshare.

For more information:

Posted in Birds | Tagged , , , , , | Leave a comment

The females of the Bahama Woodstar (above) and Inaguan Lyretail are nearly identical, but differences in song, behavior, physical measurements, and DNA recently led researchers to conclude these are two distinct species. Photo by Matt MacGillivray via Birdshare.

By Jennie Miller

These days, the discovery of a species usually requires treacherous treks into remote jungles untouched by science. But the world’s newest bird species was discovered, not in some remote tropical jungle, but in backyards in the Bahamas. A member of the bee hummingbird family, the Bahama Woodstar includes two subspecies which scientists now say should be recognized as two distinct species.

“Much of fieldwork was conducted sitting at the backyard tables of birders, holding the recorder in one hand and a cup of tea in the other,” explained Teresa Feo, a doctoral student at Yale University and lead author of the study, published in the January issue of The Auk.

The Bahama Woodstar species contains two subspecies, Calliphlox evelynae evelynae found throughout the northern islands of the Bahamas, and Calliphlox evelynae lyrura found only among the southern Inaguan islands of the chain. Both males and females of the two are strikingly similar, but in this case appearances were deceiving.


Tail shape played a major role in distinguishing the Inaguan Lyretail (right) as a separate species from the Bahama Woodstar (left). The forked, lyre-shaped tail feathers of the Inaguan Lyretail produce a different sound during male courtship display dives than the fanned tail feathers of the Bahama Woodstar. Photos by Anand Varma.

Physically, males in the two subspecies differ only in their forehead colors and forked tail feathers. These minor differences helped naturalists originally describe the birds as different species in the 1800’s. Yet James Peters ignored that precedent when he published the Check-list of Birds of the World in 1949 and lumped the species together as the Bahama Woodstar.

Sixty years later in 2009, Feo teamed up with ornithologist Christopher Clark from the University of California, Riverside, to study the bioacoustics of the Bahama Woodstar, specifically to record the pops and whistles produced when air runs along male tail feathers during mating display dives.

“We originally wanted to study the two subspecies simply to capture the diversity of sounds they might produce with their tail feathers,” said Feo, “And in the course of doing fieldwork it became obvious that they were different…and different more than just normal subspecies.”


Christopher Clark (left) and Jacob Musser (right) place a caged Bahama Woodstar female in the territory of a male in order to record audio and high speed video of male courtship displays. Photo by Jen Marks Clark.

Feo and Clark found that small differences in the tail feathers between the two subspecies resulted in distinct visual and acoustic courtship signals so that males would attract only females of their own kind.

Researchers could also distinguish between the birds just by their vocalizations. Males from the more widespread subspecies in the northern islands produced the classic hummingbird “light tinkling, rambling songs,” described Feo, while males from the southern islands sounded more like “wet squeaky shoes.” The birds also sang different calls and scolding sounds, indicating a long history of geographic separation. Because hummingbirds learn their songs from parents and neighbors, species separated by distance can develop unique dialects, much like humans. In this case, separation between the northern and southern islands of the Bahamas was enough for the subspecies to create different languages.

The team also compared beak and wing lengths, and collected tissue samples from the two populations for genetic analyses. Doctoral students Jacob Berv from the Cornell Lab of Ornithology and Jacob Musser from Yale worked together to sequence the birds’ DNA and found many species-level differences that indicated the populations have evolved in isolation for about half a million years.


Jacob Musser, Christopher Clark, Teresa Feo and Jen Marks Clark (left to right) observed and recorded the courtship displays of male Bahama Woodstars conveniently in the backyard of local birders. Photo by Jen Marks Clark.

Feo, Clark, Berv, and Musser conclude that the northern islands subspecies should keep the familiar name, ‘Bahama Woodstar’, and they suggest ‘Inaguan Lyretail’ for the other subspecies because it is found only among the southern Inaguan Islands of the Bahamas and because its forked tail shape resembles a classical lyre harp. The team will soon petition the American Ornithologists’ Union to officially recognize the species split. But exactly how the birds should be reclassified offers new dilemmas. “All of bee hummingbird taxonomy is in a major flux at the moment,” explains Feo.

The study is a reminder that new discoveries still exist close to home. “There’s a big wide world out there and a lot to learn about birds,” reflected Feo, “And sometimes there’s new stuff to learn even in your own backyard.”

For more on hummingbirds:

Posted in Birds | Tagged , , , , , , | 3 Comments

From December 2014 until February 2015, the Cornell Lab’s Science Editor, Hugh Powell, was in Antarctica following the work of Project CONVERGE scientists as they studied the food chain that supports everything from phytoplankton to krill to penguins. While there, he hosted two live broadcasts from Palmer Station, Antarctica. Watch them here to meet the penguins and learn from some of the scientists working on the other side of the world.

If you enjoyed these broadcasts, check out Powell’s blog that follows the scientists’ daily lives as they get up close to penguins, brave the dangerous seas, and more.

These livestreamed broadcasts took place January 29 and 31, 2015. If you enjoyed them, check out a list of future seminar speakers—we’ll note which upcoming talks will be livestreamed—or come visit us in person!

See our index of archived livestreamed seminars to enjoy more talks from the Cornell Lab.


Posted in Antarctica, field reports | Tagged , , , , , , | Leave a comment


By Pat Leonard

The 18th annual Great Backyard Bird Count includes Valentine’s Day this year, with the count spanning four days from February 13 through 16. That’s fitting, given that people who join the GBBC love birds and love sharing what they see.

An estimated 140,000+ bird watchers from 135 countries contributed their observations during the 2014 GBBC. Their collective effort was incredible—more than 4,000 species counted, or 40% of all the bird species in the world, over just a three-day span.

Participation is free and easy—just count up the birds you see over the second weekend in February, either right in your backyard or as far as you’re willing to venture, and report what you find on the GBBC website. For the photographers among you, check out the 2015 GBBC Photo Contest. You can start submitting photos Friday, February 13th (only photos taken during the GBBC can be entered).

Here’s a peek at what birders can expect for this year’s big global count.


A Common Redpoll (left) looks like it has an earful for this Black-capped Chickadee (right) in Ontario. Though redpolls are only winter visitors and chickadees are area residents year-round, it is important to record both species during the GBBC. Photo by Corey Hayes via Birdshare.

Snowy Owls Again, and Winter Finches

Magnificent Snowy Owls are popping up again this winter, and while there aren’t quite as many as last winter, there are still significantly higher snowy numbers than usual. Check out this eBird map showing where Snowy Owls have been reported from November 2014 through today.

Winter finches are also dropping farther south, as they typically do when seed crops are down in the boreal forests of Canada. Pine Siskins are being found as far south as Florida and Texas this year, Common Redpolls are beginning to make a good push south into the Lower 48 States, and reports of Red Crossbills are streaming in to eBird from the Pacific Northwest.

Common Birds Make for Good Science

While it’s exciting to see an unusual bird, scientists stress the importance of GBBCers reporting the regular traffic to their backyards—the chickadees, Northern Cardinals, Tufted Titmice, and Steller’s Jays—as well as the size of flocks such as Snow Geese, European Starlings, or Red-winged Blackbirds. Reporting your common bird observations during this annual four-day window may seem like a small thing, but it helps scientists analyze some of the larger and longer-trend changes in bird populations. Has the Eurasian Collared-Dove finally expanded its range into your area? Are there more ducks and geese than usual? Are Red-bellied Woodpeckers farther north than they were 10 years ago?


Green Bee-eaters, taken by Dr. Sukhendu Mukhopadhyay in Itachuna, West Bengal, India, during the 2014 GBBC.

Great GLOBAL Backyard Bird Count

In 2014, only the second year of broad international participation in the Great Backyard Bird Count (thanks to a switch to eBird for list management), bird counts were submitted from all seven continents. India was #3 among countries for checklists (behind the U.S. and Canada), and GBBC was a springboard to a vibrant eBird India community that just crossed one million observations. On GBBC weekend, watch the India page to see if they beat last year’s totals of 820 species on 3,209 checklists.

Australia, Argentina, Ecuador, and much of Central America also have growing eBird communities, and other countries are ramping up—such as Portugal, Serbia, the United Arab Emirates, Kuwait, Iran, and Taiwan, where a Mandarin language option will soon be available. New countries joining the GBBC this year include Malaysia, the Philippines, and Turkey.

After you enter your bird sightings, take a trip around the world to see what your fellow GBBCers are seeing all over the planet by using the GBBC location explorer tool.

New this year…Pledge to Fledge


It’s never too early to start encouraging youngsters to enjoy birds and nature. Photo by Bill Harrison/2008GBBC.

Nearly 70 percent of GBBC participants say they were encouraged to appreciate birds by friends, family, or colleagues. In other words, most new bird watchers are minted through a mentor who took a little time to share their passion.

To encourage that mentorship among birders, this year the GBBC is incorporating a grassroots campaign called “Pledge to Fledge,” an effort begun by the Global Birding Initiative. The underlying theory relies on basic math—if every bird watcher inspired just one other person to watch birds, there would be twice as many people who enjoy and care about birds. And once a person cares about and appreciates birds, they are much more inclined to do what they can to protect and preserve them.
Birders who want to entice someone to come along and count birds for the GBBC can find tips and materials at the Pledge to Fledge web page.

How did you become a birder?

Birding can make a big difference in the lives of young people. These students at Cornell University— who are now pursuing careers in biology, ornithology, and conservation—say they owe their love of birding to an adult to who took the time to mentor a young person. You can find ideas and tips for being a birding mentor at the Pledge to Fledge web page


BenBarkley_png“My dad introduced me to birds and taught me how to bird! So I owe it all to him!”
Ben Barkley

BenVanDoren_pngI was introduced to birding by my third grade teacher…I had been somewhat interested in birds before that, but that was the real spark.”
Benjamin Van Doren

HopeBatcheller_pngI was introduced to birding by my mom. When I was about eight years old we were hiking and found an Ovenbird nest. Never had I seen anything so cool!
–Hope Batcheller

 EricGulson_png“One of my Dad’s coworkers mentioned she was a birder and invited us to a bird outing. We went to the central highlands of Mexico to visit an alkaline lake and some pre-Hispanic ruins, saw awesome birds, and I was immediately hooked!”
–Eric Gulson

TeresaPegan_pngMy family has always been into the outdoors and wildlife…my parents would take me and my siblings to see unusual birds.
– Teresa Pegan

Posted in citizen science, Great Backyard Birdcount | Tagged , | 10 Comments
Older Entries |