Thursday, July 28, 2011

Book Review: Kaufman Field Guide to Advanced Birding

(Transcript of For the Birds for July 28, 2011
Imagine being able to go out on hundreds of birding excursions with one of the finest authorities on bird identification in the world. And imagine that he’s endlessly patient, explaining every step of how he identifies each bird, giving you a wealth of tips so you can more clearly understand why a bird’s picture in a field guide does not perfectly match the bird you’re actually seeing. His advice and information are top level, yet he is always friendly and easy to understand.

We may not all get to go birding with Kenn Kaufman, but we don’t need to as long as we have his book, the Field Guide to Advanced Birding. If you’re a beginner, please don’t let the term “advanced birding” scare you away. This book has a clearer, simpler explanation of the steps we take when looking at an unfamiliar bird to figure out what it is than any field guide on the market. I used to say that if you want to be a birder, there are two essentials—binoculars to help you see birds better, and a field guide to help you identify them. But Kenn Kaufman’s guide does more to explain in simple steps how we identify birds than any single book ever written.

The 38 pages of the book’s first and second parts, “An Integrated Approach to Field Identification of Birds” and “Principles and Pitfalls of Field Identification” can give any beginner a firm grounding that will make bird identification much easier. He also explains some of the tricky situations that can make figuring out a bird harder. Feathers may show abnormal pigmentation, can become discolored, stained, or faded, or may be broken, missing, or disarranged. Bills can be broken or deformed. A bird may actually be a hybrid with parents of different species, or an escaped pet native to another continent.

Even as he discusses the many reasons an individual bird might be harder than usual to identify definitely, he reassures his readers, “If any group of birds leaves you confused, irritated, or uninterested, it’s okay to simply ignore that group,” and notes that “As long as you’re not causing serious disturbance to the birds, their habitat, or other people, there is no ‘wrong way’ to go birding,” and continues, “I’ve often said that birding is something that we do for enjoyment—so, if you enjoy it, you’re a good birder. If you enjoy it a lot, you’re a great birder. If, as a great birder, you decide to learn more about identifying difficult species, I hope this book will help you. But if you decide not to tackle these challenges, please continue to pursue your birding in whatever way brings you the most satisfaction.”

The book has not just the simplest explanations and illustrations of feather wear and molt I’ve ever seen, but also the best coverage of how feathers are arranged. Even really advanced birders can benefit from the chapters helping identify specific groups. Seabirds, raptors, shorebirds, gulls, terns, jaegers, flycatchers, swallows, warblers, sparrows—no matter what a birder’s nemesis birds might be, Kenn’s guide has wonderful tips for reducing the number of question marks on our trip lists. And for advanced birders, the book also serves as a wonderful tutorial on how to teach novices about birds. Most birders who have been able to identify birds since childhood are not good about articulating the differences between groups that seem so obvious to them that they’ve never thought deeply about the ways they’re alike as well as different. Kenn doesn’t shout across the chasm to beginners that it’s easy to cross—the bridge is right over there. No, he walks across and leads you by the hand. In my opinion, after reading it cover to cover, Kenn Kaufman’s Field Guide to Advanced Birding is not just a great bird identification book. It’s the greatest bird identification book.

Tuesday, July 26, 2011

"Mystical" connections with birds

(Transcript of three For the Birds segments, from July 25, July 26, and July 27, 2011)
American Crow
Last week I was in Cable, Wisconsin, where a gentleman told me a most interesting story about someone who loved birds, especially crows, very much. When the person died, a group of crows gathered in a tree and remained quietly during the entire service. He saw this himself, and found it incredibly moving and significant.

I came home to a letter from a friend of mine in Washington D.C. She sent me a clipping from the Washington Post from July 14. A veterinarian named Michael W. Fox does a question/answer column for them, and the first letter fascinated my friend. It was from a J.K. in Bethesda, and read:

Dear Dr Fox:
I read with great interest your volumn about birds and your request for stories that involve te appearance of birds during an emotional or sensitive time.

I had an unusual bird event the day that my mother died.

My mother had stopped talking and was in a sleeping state. I was alone with her in her second-floor bedroom. The room was very quiet, until I heard a chirp at the window. This by itself was unusual. I walked to the window and saw the most amazing sight: The tree outside was filled with birds, and not just a flock of one kind. There were cardinals, robins, crows, chickadees, purple finches, goldfinches, mourning doves, sparrows, and one tufted titmouse.

Our minister came to deliver last rites that afternoon. I told her what had happened, and she said she’d heard of such a gathering before. Nature knows when something extraordinary is happening, and these birds were gathering for the event.
The arrival of these birds continues to amaze me and has given me hope that there really is a spiritual world beyond the living. I ponder this nature mystery and hope that sharing this will give hope to others.

Dr. Fox answered:
Readers might remember my account of an event almost identical to what you describe that occurred around the time of my mother’s death thousands of miles away.

Skeptics speak of mere coincidence, but we should not lose our sense of awe and wonder. In the metaphysics of such coincidental events might be deeper truths that mortals do not yet fully comprehend.

Those whose hearts and minds are open to nature are surely more receptive to such messages or unusual animal phenomena, especially during the passing of a loved one, than are those who are not mindful of possible spiritual connection between humans and fellow creatures.

Over the years many people have told me similar stories, and I have some of my own. Tomorrow I’ll talk about the ways birds have touched my life at some of the most profound moments of loss and what I think it means.

Brown Thrasher

Yesterday I talked about a Washington Post column by a veterinarian talking about unusual appearances of birds surrounding a person’s death. These things have happened to me, too.

When my cousin died in the early 70s, a Brown Thrasher sang outside the church throughout the funeral Mass. When his dad, my uncle, died in the 90s, his funeral was held in the same church, and again a Brown Thrasher sang outside the church. It was very lovely and moving for me, and now I can’t hear a Brown Thrasher without remembering my cousin and uncle. Of course, both of them died at the same point in spring when Brown Thrashers in the Chicago area are expected to be singing, and since the funerals were held in the same church, it’s not surprising that the same birds would be drawn to the surrounding habitat. After both, I asked family members if they’d noticed the Brown Thrasher singing, but no one else did. I can hardly attribute their singing outside the funeral to anything except my own awareness of birds. I feel richer to be able to stir up memories of two dearly-loved people whenever I hear a Brown Thrasher, but this is due to my personal connection to birds, not to birds feeling some obligation to go outside their own lives to enrich ours.

After I returned from my father’s funeral, I took a walk in my favorite park and saw a group of Buff-breasted Sandpipers. I’d never seen that species before, and wouldn’t have expected them where I saw them, but it was early September, right when they’re migrating, and you never really know what to expect when you go birding. I still found it exceptionally moving to have that particular species, lovely in a soft, literally grounded sort of way, appear when I felt so bereft and lost.

I was very close to the uncle who was my godfather. He loved the outdoors as much as I did. I stayed with him and my aunt for a few weeks while he was dying. When I needed a few minutes of respite, I’d leave their Chicago lakeshore apartment to take a little walk along the lake near Montrose Harbor. He died in late summer, when birds were first starting to migrate. I hadn’t spent much time birding in that area along Lake Shore Drive before, and the birds I was seeing in there were extraordinary. I could have attached all sorts of spiritual significance to them being there as if they were gathering in recognition that my uncle’s ebbing life was a cosmic event. But that area of the lakeshore is actually well-known to be a migration magnet. There was no magic involved, even if seeing those birds at such a difficult time was deeply soothing and healing for me. He died in the middle of the night, and the following morning, after all the various essentials were dealt with, my aunt went to her sister’s and my sister-in-law picked me up to take me away for a day of peace. We headed up to Hyde Park, where I finally got to see the storied Monk Parakeets that have nested there for decades. Seeing their homey little family groups was balm to my soul.

Monk Parakeet

Comforting as it is to see birds during trying times, especially ones as emotionally fraught as experiencing a death, the birds themselves are too involved in their own lives to be spending time providing symbolism and meaning for our lives. Tomorrow I’ll talk a bit more about why we attach such significance to birds, but why we diminish the meaning and significance of their lives when we get too carried away with this.

Snowy Owl

My father-in-law died during a Snowy Owl invasion. For weeks, every morning either my husband or I, or both of us, drove to Port Wing. And every single day, we saw at least one Snowy Owl, and sometimes several. Many people believe seeing an owl portends a death, but really, no more people died that winter than other years, and other people I’ve loved died without my seeing a single owl near the time of death. And most people seeing those owls didn’t lose anyone that year. Those owls weren’t there because my father-in-law was dying—they were there for reasons particular to them, but their presence, though unconnected in any way to me, was endlessly comforting to me.

Something deep within humans makes us yearn to understand the universe and our place in it. Ironically, this human need is precisely at the crux of both science and religion. Scientists look at birds and see research subjects that can help us understand evolution, animal behavior, how brain neurons regenerate, and all manner of other subjects. Other people look at those same birds and see mystic connections to angels—indeed, virtually all depictions of angels show them with bird wings. To raise birds even higher in our spiritual awareness, Christians have the New Testament line about God noting the fall of a sparrow. Some bird songs are ethereally beautiful, and they seem to fly almost up to the sky, which many of us associate with heaven.

White-tailed Deer

Even people who don’t belong to any religious faith usually have some sense of yearning that our love for nature is requited. Robert Frost wrote a lovely poem, Two Look at Two, about a couple taking a walk and encountering a doe and then a buck in the woods. He ends it:

Still they stood,
A great wave from it going over them,
As if the earth in one unlooked-for favour
Had made them certain earth returned their love.

Black-capped Chickadee

I’m pretty sure that when I die, my kids will look at chickadees differently. But I trust they won’t think my soul is flitting around in those tiny beings who have plenty enough on their plate as it is without having to drag human spirits everywhere they go. Many of us, especially me, look to birds for spiritual comfort, but that shouldn’t require molding birds into our spiritual needs.

Brooks Atkinson wrote:
Although birds coexist with us on this eroded planet, they live independently of us with a self-sufficiency that is almost a rebuke. In the world of birds a symposium on the purpose of life would be inconceivable. They do not need it. We are not that self-reliant. We are the ones who have lost our way.

But looking at birds can help us find our way. When it comes down to it, seeing birds as birds, not as angels or messengers but simply as themselves, whether flying in the heavens or pulling worms from the earth, is plenty beautiful and evocative enough. While grappling with breast cancer, Rachel Carson wrote,
There is symbolic as well as actual beauty in the migration of the birds; in the ebb and flow of the tides; responding to sun and moon as they have done for millions of years; in the repose of the folded bud in winter, ready within its sheath for spring. There is something infinitely healing in these repeated refrains of nature, the assurance that night after night, dawn comes, and spring after winter.
Terry Tempest Williams wrote in her lyrical book, Refuge:
I pray to the birds. I pray to the birds because I believe they will carry the messages of my heart upward. I pray to them because I believe in their existence, the way their songs begin and end each day—the invocations and benedictions of Earth. I pray to the birds because they remind me of what I love rather than what I fear. And at the end of my prayers, they teach me how to listen.


Thursday, July 7, 2011


Black-capped Chickadee fledgling

(Transcript of For the Birds for July 8)

I love watching chickadees every day of the year, through every season, and it seems especially fun in summer. Watching my neighborhood chickadees splitting into pairs and raising families is very fun. The males start out so solicitous of their mates, feeding them before they take a bite themselves, during courtship and while the female is incubating their eggs. Then the babies hatch out, and dad gets totally focused on providing food for the young. He may start ignoring his mate’s plaintive begging, knowing she’s perfectly capable of finding her own food. Some females don’t seem to mind at all—they are just as focused on feeding their young as the male is. But there’s a lot of individual variation in chickadee behaviors, and it’s fun to watch each pair work out their priorities.

Black-capped Chickadee

This year when I was at Hunt Hill Audubon Sanctuary, I got to watch Bruce Bacon, a wonderful bird bander, band an adult chickadee, and I took photos of her enormous brood patch. Right when summer heat makes extra insulation unnecessary, birds that incubate eggs tend to lose all the down feathers from their bellies. You can’t notice this when they’re flying about because their outer feathers are broad enough to cover the bald area, but a chickadee can part the feathers away so while she’s incubating, her hot skin can be pressed directly on her eggs. And because she lays as many as 13 eggs, her brood patch is very large, allowing her tummy to be in contact with the entire clutch.

Black-capped Chickadee brood patch

During the two weeks that the chicks are in the nest, both parents are run ragged flying here and there in a constant search for food. Keeping all those mouths filled from sunup to sundown is exhausting work. And the parents also have to keep the nest clean, which they do by carrying away the babies’ fecal sacs as quickly as they produce them. I got photos of that process at Hunt Hill, too.

Black-capped Chickadee

Once the babies finally leave the nest, the parents’ duties are far from over. Before they’re good at flight, the little fledglings stick together and their parents bring food to them. But it doesn’t take more than a few days for the little ones to get impatient and start following their parents everywhere, constantly begging by fluttering their wings, opening their wide mouths, and making insistent little sounds.

Black-capped Chickadee fledgling

The parents don’t have time to rest or preen, and their feathers grow increasingly ratty looking. This coincides with the parents starting to molt, giving them an even more disheveled appearance. In my neighborhood, the baby chickadees from this year are full sized now, even their tails full length, but they’re easy to distinguish from the adults because the young birds have perfect plumage and still have yellow mouth linings. The adults look ridiculously bedraggled right now—I’ve taken some photos that are on my blog. [Well, THIS is that blog.]

Bedraggled Black-capped Chickadee

During August, chickadee families will all be breaking up and the young dispersing. Regardless of how devoted and attentive the parents are right now, the young will each head off on their own to join a flock different from the flocks of each of their brothers and sisters and their parents. No one knows what triggers this—the parents continue to feed the young and don’t act aggressively toward them, but suddenly the young will be gone. By then the parents will be wearing new plumage again, and rejoining their old winter flock and welcoming in new young chickadees, unrelated to any of the adults, and working out a new flock hierarchy. No matter where today falls on the calendar, today is the ideal time to watch chickadees.

Black-capped Chickadee



(Transcript of today's For the Birds)

If I had to choose 10 favorite bird songs, the list would definitely include the Veery. This mellifluous song cascades through woodlands most reliably in the evening, right when many people are sitting on their porches to enjoy the performance. Veeries belong to the genus Catharus, which comes from the Latin word pure, in reference to the pure tones of these thrushes’ songs. Intriguingly, another North American bird whose name start with V, the Turkey Vulture, also shares the derivation of its scientific name, Cathartes, but for a wildly disparate reason. The Turkey Vulture genus name was given in reference to a cathartic, which purifies or purges the digestive tract. When a predator approaches a vulture who can’t escape, the vulture purges its stomach contents via projectile vomit. Vultures like their meals not just merely dead but really most sincerely dead, and what comes out their throats is much, much yuckier than what went in. Fortunately for those of us who enjoy Veeries, what comes out of their throats is pure and sweet. Veery songs sound similar to our ears, but Veeries can distinguish fine points in one another’s songs to recognize the sounds of their neighbors, which don’t seem to upset them. But they react aggressively when an unfamiliar Veery song is heard near their territory.


It’s rude to play recordings of their song to draw them close because they get so distressed. If a person must play a Veery recording for research or other purposes, it’s kindest to play the song very softly before stopping. In a 1956 study, researchers found the louder a taped song was played, the more a Veery tried to escape; the lower the volume, the more likely the bird was to assume an attack stance. Both the bird and his mate might assume he lost the encounter if he was retreating during the last, loud song played, but that he won the encounter if the sound grows softer and then disappears.


The Veery isn’t the only thrush in the upper Midwest—robins are the most abundant, but in our own north woods we also get Swainson’s and Hermit Thrushes, and even an occasional Wood Thrush. Of all these species, Veeries prefer the youngest, wettest woods—I expect to hear them wherever I see a dense stand of ferns. During migration through Central America, they are more drawn to mature second growth forest, and that’s also their preferences on their winter range in the cloud forests of southern Brazil. Every Veery who we’ve heard singing this year has already made at least one round trip journey a minimum of 5,000 miles each way. The oldest Veery on record was an adult female caught in New Jersey in July 1980, and recaught, alive and healthy, in July 1989, when it was a minimum of 10 years old and had migrated over its lifetime a minimum of 100,000 miles.


During the brief time that Veeries are with us, from early May through late August, they mostly remain hidden in the vegetation, unobtrusively raising their young on insects and fruits and trying to steer clear of snakes, chipmunks, red squirrels, and other predators of eggs and chicks. White-tailed Deer are known to eat the eggs and chicks of ground nesting birds, though I couldn’t find any data establishing that they are a significant problem for Veeries as predators. But deer also browse the understory plants that define Veery habitat. During their nocturnal migration flights, they’re frequent victims of collisions with lighted structures. And on their wintering grounds they are harmed by deforestation. It’s tough to be a Veery, and sure enough, their numbers throughout the continent have been declining steadily since the 1960s, especially in a large swath of land that includes Minnesota and Wisconsin. I don’t know what we need to do to protect these beautiful birds with their shy ways and sweet songs, but without them the north woods would be diminished indeed.


Tuesday, July 5, 2011

Golden-winged Warbler

Golden-winged Warbler
(Transcript of today's For the Birds)

A year or two ago, a Penn State student named Anna Sewell was taking a seminar course about endangered species and became fascinated with the plight of the Golden-winged Warbler. She wrote a paper about the little bird, and became so alarmed with how grievously its numbers were declining that she kept working on the project and finished the rigorous research required to file a petition with the U.S. Fish and Wildlife Service asking to have the bird officially listed as threatened or endangered. She filed her petition on February 10, 2010—a year and a half ago. The petition was referred to the Division of Ecological Services, who had to make two key decisions. First, they had to make a 90-day finding, in which they decide whether the information in the petition is substantial enough to justify additional evaluation. In this case it was. Next they must prepare a 12-month finding, based on a review of the scientific evidence, and a call to state agencies, organizations, and the public for additional relevant information. Then a document is prepared to explain whether the petitioned listing is warranted, not warranted, or warranted but precluded. Warranted but precluded means that the species does warrant listing, but that other species have higher priority in the decision queue; after listing decisions are made for those species, the warranted but precluded species will get its turn. Evaluation is based on the criteria of the Endangered Species Act: the likelihood of extinction in the foreseeable future throughout all or a significant portion of the species’ range. If a species is ultimately listed, the next step is normally the preparation of a recovery plan. It can take several years for meaningful actions to occur that actually help a species to recover.

Golden-winged Warbler

The Golden-winged Warbler proposal is still in the one-year review stage, and so it will be a while before it gets any help under the Endangered Species Act. But it’s tricky researching the species to help figure out why it’s declined so egregiously in virtually all its range except a small part of Northern Wisconsin and in Minnesota west of a line from Duluth to the Twin Cities. For one thing, Golden-winged Warblers are one songbird that simply doesn’t deal well with some research techniques. A pilot telemetry study in Kentucky found that of that of four male Golden-winged Warblers tagged with radio transmitters, two disappeared from their territories and were not observed in the study area again. This species is also exceptionally vulnerable to communications towers—their mortality at these towers during nocturnal migration is exceptionally high relative to other species that are orders of magnitude more abundant but have only slightly higher mortality. States in the Appalachians and the Northeast have lost virtually all their Golden-wings even where appropriate habitat appears to be available.

Golden-winged Warbler

The last holdout where Golden-winged Warblers are surviving in strong numbers is in central and northern Michigan, central and northern Wisconsin, and central Minnesota. Its population is expanding in Manitoba. Many of us are lucky to live where the tiny warblers are still easy to find, but based on their rapid decline in eastern states, this is a bird that should not be taken for granted. It took a Penn State student to get Golden-winged Warblers the attention they deserve. Maybe it’s time for us non-professionals to take similar initiative to demand that other seriously declining species, such as Evening Grosbeaks, to get similar attention.

Golden-winged Warbler

Monday, July 4, 2011

Falcon Independence Day

"Waters" the Peregrine Falcon

(Transcript of today's For the Birds)
If you have any money to spare in these tough times, PLEASE consider donating to Duluth's Peregrine Watch program!

Every year right around the Fourth of July, baby Peregrine Falcons make a break for independence by taking their first flights. Since May they’ve been peering out of the nesting box on the Greysolon Plaza building, and they’ve spent many hours flapping their wings and then jumping from the box to the ledge of the building, and walking tentatively along the ledge. But the first leap from the ledge or box into mid-air requires both a leap of faith and some anti-gravity karma. We’ve lost birds in past years who crashed into windows, and because so many tourists flock to Duluth during the very weekend that the birds are most vulnerable, heavy downtown traffic is a huge risk.

"Waters" the Peregrine Falcon

I spent several hours downtown on both Saturday and Sunday, watching the newly-fledged chicks. I joined Hawk Ridge’s Peregrine Watch group, led by the effervescent Julie O’Connor, on Saturday. The one named Waters took her first flight on Saturday morning, and then stayed in one place, sitting tight on some ventilation ductwork, the entire day. She can be recognized at the right angle with good binoculars because her leg band has a W and a 71.

"Waters" the Peregrine Falcon

The other chick, named Laura, fledged on Friday, so she was a bit more adventurous, flying on several rooftops. Her leg band has a W and a 70.

"Laura" the Peregrine Falcon

Julie is an excellent observer and also has some magical peregrine intuition—she always seems to know where all the birds are.

Laura's night on the town

On Sunday, I tracked them with the wonderful photographer Mike Furtman.

Mike Furtman photographing Peregrine Falcons

One bird sat tight for several hours on one of the ornamental decorations on the Greysolon building. We assumed that one was Waters...

"Laura" the Peregrine Falcon

...and that the more restless one on the roof of the Duluth Opera House and the Norshor Theater Building was Laura until she came close enough for us to see the 71 on the band—she was actually Waters.

"Waters" the Peregrine Falcon

I got lots of photos. The female falcon nesting in the box on the Greysolon Building had been a bird named Amy from 2004 through last year, but she apparently died at some point before May, when people noticed that the bird nesting in the box had a different band number. The new female is named Jenna, and she has an entirely different nature from Amy.

"Jenna" the Peregrine Falcon mother

The unbanded male who has been at the box since 2003 had great teamwork with Amy, who was big and aggressive, took on every Bald Eagle who came anywhere near, and took food from him in mid-air, and then took the lead in feeding the young. Jenna is milder mannered, and even sits back allowing her mate to feed the chicks, so he seems to be working harder this year.

Peregrine Falcon

Unlike Amy, Jenna allowed me to come rather close for photographs, though it’s tricky to get good angles when the birds are on rooftops.

"Jenna" the Peregrine Falcon mother

Sunday evening while I was busy getting my photographs up on the internet, Laura the falcon was having adventures downtown. Julie O’Connor called me after getting a call from people at the casino telling her a bird had been grounded. Someone downtown had called 911 about it, and the dispatcher had alerted raptor expert Dave Evans, too. When Julie and I arrived, Laura was sitting on a car parked on Superior Street, with heavy traffic passing by and a small crowd assembled watching her.

Laura's night on the town

Laura's night on the town

Julie has been dealing with downed peregrines for quite a while, and she figured Laura would eventually fly up to a roof again, but we stayed put to ensure that when she did take off and lost altitude at first we could stop the traffic. It took at least 20 minutes, and the couple owning the car arrived well before Laura decided to release it to them, but they were patient.

Laura's night on the town

Finally she took off, narrowly missing the windshield of a tall SUV but then gaining altitude and reaching the roof of the casino.

Laura's night on the town

The next few days are going to be treacherous for the baby falcons, and scary for Julie and me and everyone else who has been following this little family. Julie says within a day or two, the flying part becomes very easy for them, but working out the landings is much trickier. I’ll breathe better when they’re truly independent.

Laura's night on the town

Sunday, July 3, 2011

Rodents vs. Birds

White-footed Deer Mouse
Transcript of July 1, 2011 For the Birds
Last week when I was staying in a lovely little cabin in northern Wisconsin, I was brushing my teeth one evening before bed when I noticed a young white-footed deer mouse in my shower stall— there was an opening in the wall where it joined the ceiling, and he’d apparently been crawling around up there until he suddenly dropped down. The shower door was closed so the little guy couldn’t get out on his own. I didn’t want him loose in the cabin, and didn’t want to hurt him, so while he was away from the door I slid it open, put in a wastebasket on its side, closed the door again, and then sat waiting patiently, and then impatiently, for the little guy to finally go into the wastebasket. The mouse was very suspicious, a quality that may serve it well in the long run but was most inconvenient for me, because although this was a small shower stall, he steered clear of the wastebasket for three full hours. Finally, he tentatively entered the wastebasket and I snatched it up, brought it out the door, and set it down on its side on the forest floor. He took a minute or two to sniff before finally leaving the wastebasket and scurrying off into the darkness. Not a minute later, a Barred Owl started hooting. I went to bed thinking about how tricky it is negotiating life on a planet where predation is such a widespread phenomenon, and hoping my little mouse would beat the odds and eke out a long and prosperous existence.

Then this week I read a newly-published paper in the Journal of Animal Ecology, about a study of how two of my favorite forest birds, Veeries and Ovenbirds, elude mammalian predators by avoiding nesting in places where they vocalize. When the researchers set out speakers playing the calls of chipmunks, both Veeries and Ovenbirds avoided a wide area around the speakers. If the speakers were playing calls of innocuous frogs, the birds didn’t show this avoidance of the speakers. White-footed deer mice don’t make much noise, so the authors didn’t play sounds of them, but in their discussion they mentioned that deer mice feed on the eggs and nestlings of these ground-nesting birds, too. Rodents actually eat eggs and nestlings both in trees and on the ground, though ground-nesting birds suffer far more from it. And I suspect smaller birds are more helpless to stop a chipmunk or mouse than larger birds are—the study found that Ovenbirds kept their nests twice as far from the speakers than the larger Veeries did.


People have long known that birds respond to their own species’ vocalizations—it’s cool that people are finally noticing that they also hear and recognize the sounds made by other species, and are able to use a wide variety of cues in their environment to make important life decisions. A lot of people still seem to think that bird intelligence is extremely limited and that most of their behaviors are based strictly on instinct, but in reality, they are far more intelligent and adaptable than we give them credit for.


So finding yet more confirmation of my beliefs about bird intelligence and adaptability was a big take home message of the study. But the other message was an added awareness of how hard mice, chipmunks, and other rodents are on birds. I still find them adorable, and can hardly judge them harshly after eating a breakfast of eggs and looking forward to a dinner of barbecued chicken. But somehow releasing that little mouse, to eat baby birds until it’s in turn one day eaten by an owl, seems more fraught with complexity than it did at 1 a.m. when I just wanted to get the little guy out of my cabin.