Saturday, December 22, 2007

More Canadian Birds Show Up in Christmas Bird Count

There was more snow on the ground than I can remember in my eleven years of doing the Brattleboro Area Christmas Bird Count (CBC). And it was colder than previous years. And when the wind blew, it was colder yet. By mid-afternoon, the clouds began moving in; the air became dank and damp and felt even colder. My heavy insulated boots kept my feet warm, but everything became chilled.

Tiny birds moving through tree tops are located by ear, not eye, and that means exposing tender, delicate flesh to the frigid air. We could sort of warm up in the car as we crept slowly from place to place, except that the windows had to be down so we could listen as we crept along, and the fan motor on the heater had to be low or off because it made too much noise. The rivers and ponds were frozen. The fields were barren and cold. There were icy patches on many roads, and no place to pull off the road when we had to stop, walk, listen, count, freeze and shiver.

I had a blast!

The annual CBC is one of my favorite days of birding throughout the year. In the late Spring, I can stand in my backyard and see or hear thirty to forty species in the early morning hours. Last Saturday, the team I was with scoured our assigned area and eventually tallied twenty-nine species. We wandered slowly along dirt roads until somebody watching or listening through the car windows cried, “Stop.” Then we tumbled out of the vehicle before it had stopped to chase an elusive sound or sight.

But in the winter landscape, when all of life seems to have gone into hiding, finding signs of life still on the move - up and about and around - is energizing and affirming. And we never know what we will find.

We almost always find wintering bluebirds in our survey area, and this year we found one lone bluebird perched on a wire not far from Brattleboro. We continued searching the orchards along our route. Sooner or later we almost always find bluebirds working through one or more of these orchards, but not this year.

In the mid-afternoon we were in a dense stand of hemlocks; Juncos moved through the forest understory. Watching them, and counting, we were led to a Golden-crowned Kinglet in a small, leafless beech, and that lone kinglet led us to more kinglets. Conventional wisdom has it that several species will forage together through the winter woods, and we soon found the only Brown Creeper of the day, inching its way up a huge hemlock, then following the juncos and kinglets south along the road. Movement deep in the woods caught our attention. A larger bird ... another ... and another. One landed on the road forty feet from us, picked salt and grit from the road, and flew. Eastern Bluebirds - thirteen in the flock.

About thirty people participated in this year’s CBC. Seven teams surveyed assigned areas and counted the winter birds. One team searched frustratingly all day and tallied only a few species and few numbers. But they had a great time following mammal tracks. Numbers often seemed hard to come by. But by the end of the day, forty-eight species had been tallied with an unofficial total around 3000. Additional “count week” species brought the total for this year’s CBC to fifty-five.

Fifty-plus species has become the norm for the Brattleboro CBC. The species vary from year to year. Each year there are a few species reported which have no business being here; they should have gone south long ago. This year there was a Great Blue Heron seen in flight, and a Northern Flicker. Species recorded for the first time were Yellow-bellied Sapsucker (two) and an American Woodcock. These migrants should have migrated before now, and quite frankly, not having done so may be a fatal mistake.

With almost no open water, it was no surprise that Canada Geese (some years there are hundreds) were completely absent as were most other waterfowl. A few ducks were found in the open water above and below the Vernon Dam and where Whetstone Brook enters the Connecticut River.

Totals for most of the usual wintering birds were close to the average for the last nine years. Here are a few “Average/’07 Count” - American Crow: 230/74; Blue Jay 195/161; Black-capped Chickadee: 447/576; Downy Woodpecker: 42/38; Hairy Woodpecker: 15/27; Tufted Titmouse: 54/54; Northern Cardinal: 34/41; Mourning Dove: 196/206; White-breasted Nuthatch: 58/55.

Count numbers for the invasive birds that no one likes but which feed the wintering hawks also matched recent numbers - European Starling: 362/336; Rock Pigeon: 285/ 271; House Sparrow: 211/166

The significant difference this year was the presence of wintering finches. Reports of birds irrupting south from Canada (where many seeds crops failed this year) have been coming from all over the Northeast. But we had to find them on count day, and we did. We counted fifty-one Common Redpolls, probably an undercount - since these birds are very nomadic as they forage. One year counters found a single flock of redpolls with over 200 birds, but not this year. There was a flock of twenty Snow Buntings, a scattering of forty-plus Tree Sparrows, and fourteen Evening Grosbeaks.

The buzz came with two other winter finch species which have only been recorded once in the last dozen years. In 2001, eleven Pine Grosbeaks were reported. This year, eighty-one were counted. These large, tame, red and gray male - or olive and gray female - finches are being found in fruit trees and berry bushes in many locations in southeastern Vermont. They stripped my loaded crab apple weeks ago.

The other finch species, also last reported in 2001 during count week, was found in a pine forest atop Stratton Hill in Newfane - five White-winged Crossbills. This is be the first time our CBC has recorded an actual count number for this species which feeds on pine and spruce cones.

So it was cold, and wintery, and sometimes difficult to find the birds. But the end result is a snapshot of the bird life present in the Brattleboro area in the middle of December. Added to the results of thousands of other counts done around North America, we also contribute to a snapshot of the continental bird life. These accumulated snapshots from many years help researchers analyze the health and well-being of the birds, and more importantly, of the state of the environment and climate on which the birds - and all other life, including us - depend.

And it was fun. The Christmas Bird Count is always a good day spent with some crazy bird nerds and resulting in - by definition - a day of good birding.

Saturday, December 08, 2007

Winter Finches Have Arrived

Winter finches have arrived! They’ve been expected, and the reports from around the state indicate that they are here. Birds that breed in the boreal forests of Canada and winter in those forests, are on the move and are being seen in widely through the Northeast.

During Monday’s snowstorm, I was continually distracted from my Christmas baking by the need to take photographs through the kitchen window. There were more Common Redpolls at my bird feeders than I have ever had - a flock of thirty to forty feasted on my largess throughout the day. On at least one occasion, redpolls occupied the six perches on the thistle feeder, the nine perches on the sunflower feeder plus the rim, and lined the mixed feed seeder. Another eighteen crowded the platform feeder. Two squeezed onto the window feeder, while others waited in line impatiently. With the camera set next to the window, I frequently interrupted my baking to snap off another batch of photos.

Mixed in with the redpolls were goldfinches and siskins. An Evening Grosbeak showed up around noon. And all of the neighbor residents came by - chickadees, titmice, cardinals, doves, pigeons, jays, nuthatches, downy and hairy. Judging by an increased noise level around noon, there may even have been a Sharp-shinned or Cooper’s Hawk in the area for a while.

It is the winter finches that have bird watchers in a mode of heightened anticipation. And they’ve been that way for at least a month, maybe two. One of the grandaddies of Vermont birders posted a message on the VTBird listserve last weekend that said simply - “Redpolls finally!” With reports of Common Redpolls coming in from all over, he had been feeling frustrated that he had missed them.

Redpolls generally appear in notable numbers in the Northeast every other year. There were very modest numbers in the winter of ‘05-‘06. Looking through my records, I had a couple at my feeders briefly in early January, ‘06. I have never had the flocks like I had early this week.

What’s happening? And why have birders been expecting it?

Ron Pittaway of Ontario Field Ornithologists makes a prediction each year about the movement of birds during the winter. He collects information from the Ontario Ministry of Natural Resources about food sources in the boreal forest and then does what most in the birding community are unwilling to do: make predictions. His late September predictions for this winter put bird watchers in a state of agitation.

Finches are seed eaters in the winter, and throughout most of Ontario and western Quebec, coniferous and deciduous trees had a very poor seed crop. Here is one of Pittman’s predictions: “There will be a big flight of redpolls into southern Ontario and bordering United States. Seed crops on white birch, yellow birch and alder are very poor in most of Ontario. Expect redpolls at bird feeders this winter.”

I began to wake up to what was happening in mid-October when Pine Siskins started appearing at my bird feeders in significant numbers. Some years, they barely appear at all. But cone crop failures caused most Pine Siskins to leave Canada’s boreal forest in the summer. The energy expended in long flights is high. This year, with the shortage of food, the expense of not traveling south is even higher. I suspect that many siskins have continued to roam southward, but I also expect that they will be seen regularly throughout the winter and into the spring.

In mid-November, my spouse returned from a late afternoon walk along Augur Hole Road and casually mentioned that there was a flock of Pine Grosbeaks feeding in some cherry trees. At the same time, a neighbor called to share bird reports. I passed along the grosbeak report. Fifteen minutes later when I drove along Augur Hole Road looking for the grosbeaks, he was there on his bike. Neither of us had seen this boreal species for several years. The tame flock of twenty-plus birds allowed us to approach within a few feet of where they were feeding.

When I finally found Pittaway’s prediction report, I read: “[The Pine Grosbeak] will irrupt south of the breeding range because crops on native mountain-ashes (rowan berries) are generally poor in northeastern Ontario and across the boreal forest ... After irruptions, Pine Grosbeaks return north earlier than other northern finches. Most are gone by late March.”

Other finches which are likely to be moving southward because of the seed failure are Purple Finch, Red Crossbill, White-winged Crossbill, and American Goldfinch.

Flocks of Common Redpolls should be checked carefully for Hoary Redpoll. An adult male Hoary is sometimes described as a "snowball," and is said to be fairly easy to identify, but females and first year Hoarys are very difficult to identify.

There are other passerines which are also affected by the seed crop failure. Red-breasted Nuthatch is likely to seen more often than usual. The year-round Red-breasted Nuthatches are likely to be joined by those from further north.

Bohemian Waxwings are already being reported with unusual frequency. Like the Pine Grosbeaks, they like mountain-ash berries, and there are few of those in the Bohemian’s normal home range. They will sometimes join the large nomadic flocks of Cedar Waxwings, but we should also be alert for flocks of just Bohemians.

It has been several years since a Boreal Chickadee has been reported in southern Vermont, but this could be the year. Gray Jays in Canada are on the move. I know of no reports of Gray Jays as far south as southern Vermont, but if they need food, they may wander far out of their normal range.

Northern Shrikes are being reported frequently. Most birders know the Northern Shrike as a predator of songbirds, but in winter their prime food source is the meadow vole. The meadow vole population in the Hudson Bay lowlands, after an abundant summer, suddenly crashed in October and November.

The abundance of meadow voles during the summer meant that northern owls had a great deal of breeding success. But now those owls, like the shrikes, will be looking for food. Significant movement of owls has been reported throughout the Fall. Northern Saw-whet Owl, Northern Hawk Owl, Boreal Owl, and Great Gray Owl, - all might be expected.

This is a good time to spend time with a copy of Sibley’s Guide to Birds. This guide presents the most illustrations of plumage variations. Study these possible winter visitors. Then expect the unexpected. If you are unfamiliar with the birds, be cautious. If possible, take a photo. Be alert.

The predictions, and the reports so far, point toward a winter of very good birding.

Saturday, December 01, 2007

Shorebirds in Hawaii Have Remarkable Journeys

When I was in California a few years ago, there were two wintering shorebirds that I was unsuccessful in finding: the Pacific Golden-Plover and the Wandering Tattler. The plover is closely related, and very similar, to the American Golden-Plover which appears along the New England coastline in very small numbers (usually juveniles) during the Fall. The two were considered one species until 1993. The Wandering Tattler is similar to our Spotted Sandpiper which is common along our New England streams. The tattler is larger; it wanders widely along Pacific coastlines after finishing its breeding task. Both the Pacific Golden-Plover and the Wandering Tattler nest in Alaska and northwestern Canada. The occasional report of one of these species on the Atlantic coast are usually dubious.

With no chance of seeing either bird in the East, I had hoped to see them on that trip to California. In the tattler’s case, I gave the search especial diligence, returning to a rocky piece of coastline several times where one was known to be spending the winter. No luck.

The main problem with looking for these North American birds along the Pacific coast of California is that they winter there in very small numbers. However, had I gone 2000 miles further west across 2000 miles of open ocean with no land along the way, I would have had no trouble in finding these two shorebirds.

On our first day in the Hawaiian islands, we were trying out one of the many beautiful beaches on Maui. It was late afternoon; the low sun cast a warm glow on the palm trees, the white sand, the gentle surf, and the many sun worshipers. I was enjoying all of the sights (although some of the sun worshipers I enjoyed more than others). The beach was interrupted by a jagged crop of lava rock. I noticed a shorebird silhouetted atop the rock and immediately forsook the other sights for a closer look at the bird. Maybe it is a sign of age that I so readily abandoned some of those sights for a bird, but ... this bird was a slim, sleek, gentle-looking, golden-brown shorebird. Pacific Golden-Plover.

Two days later, we were returning from a snorkeling trip to Molokini Crater (where a whole new underwater world of beauty had been opened). Walking back to our car along the rocky shore, I noticed a shorebird. Like the golden-plover, it was silhouetted atop the rocks. Like most shorebirds, it was rather nondescript - shaped like a Spotted Sandpiper, mostly gray and streaked gray. Its body perched atop bright yellow legs; its tail bobbed from time to time. Wandering Tattler.

Subsequent to these first sightings of the golden-plover and the tattler were many more. The Pacific Golden-Plover is an abundant wintering bird in the Hawaiian Islands. Occasionally I saw it on a rocky shore, but more commonly it was foraging on golf courses and the grassy expanses of lawns, city parks, and cow pastures. It ran with short bursts, then stopped to feed on insects and invertebrates, then ran again.

On the Big Island, Hawaii, we stayed in a home on the edge of a thermally heated lagoon filled with native tropical fish. (Yes, life can be difficult.) Near the edge of the lagoon, I lifted my head to clear water from my snorkeling mask. Ten feet away, a gray bird bobbed its tail, then uttered a “tattling” call as it flew off. But not to worry - it was regular around our lagoon, often choosing the grassy edge to preen and rest.

The Hawaiian Islands are so isolated that relatively few birds found their way across the oceans and survived. The several species of Hawaiian honeycreepers are believed to be descended from a single undistinguished species of finch related to such birds as goldfinches and crossbills. Only a handful of birds found the islands, stayed put, and have gone, or are going, their own evolutionary way. In wetlands there is the Hawaiian Coot (related to American Coot), Hawaiian Duck (related to Mallard), Nene (related to Canada Goose), Hawaiian Stilt (a sub-species of Black-necked Stilt) and Common Moorhen (an Hawaiian sub-species).

However, this extreme isolation of the Hawaiian Islands presents no barrier to a few species of shorebirds, notably the Pacific Golden-Plover and the Wandering Tattler. These birds make a remarkable journey twice each year. As the short Arctic summer wanes, these birds bulk up in western Alaska. Then, they fly some 3000 miles non-stop. Adults make the trip in August. Juveniles, with no adults to guide them, do it in late September. Once they have begun their flight, there is no choice about the flight being non-stop. There is no place to stop. There are no islands on which to rest along the way. If one of these birds burns up its fat reserves before reaching the islands, it dies.

The Pacific Golden-Plover makes the non-stop flight in about two days, flying at speeds somewhere around sixty miles per hour. It is no wonder that the bird appears thin beneath its feathers when it arrives. It is thin. The plover spends the winter, restores its fat reserves toward spring, and makes the northbound journey in May

Like the Wandering Tattler and the endangered Bristle-thighed Curlew, the Pacific Golden-Plover winters on tropical islands throughout the Pacific. Why would birds evolve such a physically demanding migration pattern? I could speculate reasons, and scientists probably have some empirical explanations. But I am content, for the moment, to gape at the journey.

One thing I do not have to speculate about. Randomness does not figure into the migratory journey. The birds which make this long flight across the open Pacific waters know where they are going. Individual Pacific Golden-Plovers will return to the same spot on the same island year after year. On that favored spot - the fairway of the third hole of a particular golf course, for example - that individual golden-plover will aggressively defend its wintering territory from others of its kind. The same bird will often be in the same spot day after day and will return year after year. It may share the general territory with aliens like the Common Myna or Cattle Egret, but it is loath to share it with another golden-plover.

I enjoyed wandering the beaches in Hawaii. The beach fauna came from all over and in many sizes and shapes. Most sported minimum winter plumage. And some beach fauna, in shape and minimum plumage, were truly eye-catching. But with the exception of a few island residents, all came with the help of technologically sophisticated navigational instrumentation operated in their behalf. By contrast, the Pacific Golden-Plover and the Wandering Tattler have been finding their way to these same places with only their own inherited resources. For me, most of the time, that makes them the more interesting and fascinating.

Good birding!

Wednesday, November 28, 2007

A Few Hawaiian Birds

Here are a few Hawaiian birds that I probably will not be writing about in my regular Brattleboro Reformer column, but which deserve at least one mention and photo.

First, two endemic honeycreepers.

The I'iwi is an icon for endemic Hawaiian forest birds.

The Apapane is the honeycreeper which I saw most often while in the islands, but it rarely stayed still long enough for a photo. It's red, like the I'iwi, but the black bill in the photo betrays its identity.

The Red-crested Cardinal was common on Maui, Hawaii, and Kaua'i. While non-native (introduced from South America), it is still a stunning bird.

Also from South America, also a stunning bird, but found only on Hawaii, is the Yellow-billed Cardinal.

The Spotted Dove, also known as the Lace-necked Dove and on the islands as the Mountain Dove, was introduced from Asia in the mid 1800s.

Saturday, November 17, 2007

A First Encounter with Birds in Hawai’i

I just got back from Hawaii. I did not go to the islands to watch birds. I went to help with grandchildren, handle luggage, cook, and to be a tourist. Nevertheless, whenever possible I paid attention to the birds.

When I travel to a new place, I learn about the place, and its bird life, in advance. In the case of Hawaii’s birds, this book knowledge came from two slim volumes. From these guides, I learned that the birds most sought after by birders would be very difficult to see. These endemic species are largely confined to mountainous forests; they are often rare, many are endangered, and some may be extinct. On the other hand, in the areas where human impact is the greatest, Hawaii’s bird life has become an avian melting pot, with alien species from around the world having found open ecological niches where they can thrive. Since even most these alien species were birds I had never seen before, I approached the islands with anticipation and expectation.

A good rule of thumb in this journey of life is to keep limits on one’s anticipation level. To wit: the first bird I saw after traveling some five thousand miles was in the Maui airport’s baggage claim area. While corralling luggage, and recounting the checked bags of six people, I noticed birds flying about. With no glass walls or electronically controlled doors, and oblivious to all security stations, House Sparrows scavenged the terminal for crumbs dropped by weary travelers. Yes, House Sparrows - those ubiquitous little brown birds that occupy the ecological barrens in our cities and towns, and even wander into the lush gardens of the rural village where I live.

Ah well. I was still in anticipation. The next morning I was up at dawn. With coffee in hand, I stood on the lanai (the Hawaiian word for porch or deck, in case you’ve never been to the islands), watched the sky lighten, saw the cloud caught on the mountain peak of West Maui turn pink, and listened to the cacophony of bird song. It was wild, noisy ... and new. It seemed like some thirty or more birds were greeting the new day. Through several more cups of coffee, I listened and watched, and began to impose some order and make identifications.

None of the birds I saw that first morning were endemics. All are native to somewhere else in the world. The rooster that was crowing may have the best claim to being a true Hawaiian bird. It was a Red Junglefowl, a chicken brought to the islands by the first Polynesian settlers a millennium and a half ago. Occasionally during our time in Hawaii, we saw one that was tethered, but most were free ranging, feral or semi-feral, and in the jungles, truly wild birds. And stunningly beautiful! Just as noisy, but much plainer, was the Gray Francolin, a game bird introduced from India, that was foraging on a nearby lawn and flew briefly to the roof of our house.

During the course of the morning, I identified new birds and sorted out the many songs and calls I was hearing. Eventually, I thought I was recognizing some familiar sounds - a mimic who was repeating songs in triplet, a clear “chip” call, and snatches of a warble. They seemed familiar because they were familiar: Northern Mockingbird, Northern Cardinal, and House Finch. Each behaved just as I would expect them to behave on any day of the year in Vermont. The mockingbird sang from the tip-top of a palm tree. The cardinal skulked through the lower thicket, his presence betrayed by his brilliance.

There were doves, the Spotted and the Zebra, both Asian natives, both occupying the niche we might associate with our Mourning Dove, both with haunting coos like our dove.

Two small songbirds were common in our yard. The Java Sparrow was unlike any bird with the “sparrow” name in North America. Far from being a little brown bird, this sparrow is warm gray with a black cap, a bold white cheek, and a large beak (proportionately bigger than a cardinal’s) that is bright red at the base, fading to white at the tip. The Japanese White-eye is a green, warbler-like bird with a bright white eye ring. Both are beautiful birds, but as alien species in Hawaii, they often move into the habitats of native species and pose a threat to those species.

As I have already written, standing on the lanai with my cup of coffee that first morning, I heard at least thirty different birds. If you have been counting, you will realize that I have named nine species. The other twenty-one plus birds that I heard that morning were the Common Myna.

The Common Myna, native to India, is a close relative of our European Starling, and like our starling, is an adaptable and successful introduced species. It looks something like a juvenile starling with a dark head cap. It has a yellow teardrop behind the eye, bright yellow legs and beak, and shows large, splashy white patches on its wings when it flies.

The myna does not often mimic other sounds, but it doesn’t need to. Its repertoire of whistles, squawks, and chatter is diverse ... and loud ... and constant. Imagine the various calls and screams made by a flock of Blue Jays, then throw in the additional variability of the mockingbird, catbird, thrasher, and starling, and you begin to get a sense of the myna’s vocal presence.

I know that the myna is alien to Hawaii, and as such, probably poses threats to endemic species, but I liked the myna. It travels in pairs and gathers in flocks. It gleans insects - or anything else edible - around airports and hotels, on golf courses and lawns, in landscaped gardens and dense tropical jungles. And all the time, it is chattering.

The Common Myna was simply entertaining - a starling with the roguish love-ability of a Blue Jay. That first morning a pair landed on the lanai and hopped toward me. When I stepped tentatively in their direction, they hopped back. When I took two more steps, they flew to the railing, then the roof. One more step on my part, and they flew to a palm. They chattered to one another, then changed trees and squawked some more. When I ignored them, they came back to the lanai and we replayed the whole scene.

It took me another day to formulate a theory about this behavior, and a third day to test the theory. With the help of our four-year old, we placed some stale bread crumbs on the railing of the lanai, then pretended to do something else. Sure enough, one myna came right to the crumbs, and a second one followed. We repeated the experiment. This time the pair came together and gulped down the crumbs. They also talked with each other, and it seemed to me that one of them said, “It took that dummy long enough to figure it out.” And the other one agreed. I tried to explain to them that back home the Blue Jays are too impatient to wait around and beg, while my chickadees thank me when I feed them. But the mynas didn’t seem to care about my explanations.

Which reminds me - I’d better go check my bird feeders.

Sunday, November 11, 2007

Turkey Vultures - Avian Victims of Prejudice

The Turkey Vulture is not one of my favorite birds. Like most people, I prefer the cuteness of the chickadee or titmouse, the comic antics of the nuthatch, the gaudiness of the Wood Duck or Harlequin, the majesty of the Bald Eagle, the power of the stooping Peregrine, the ethereal song of the thrushes, or the sheer endurance and metabolic efficiency of a long distant migrant, like the Blackpoll. The Blackpoll burns fat reserves in its one ounce body during a 2000 mile journey across open ocean at the equivalent rate of an automobile which would get 750,000 miles per gallon.

Nevertheless, the Turkey Vulture is a much maligned bird, and the victim of what can only be called ignorant and irrational prejudice (if you will excuse the unnecessary and redundant adjectives).

First, some background. The Turkey Vulture is a relatively new arrival in New England. In the first half of the nineteenth century, Audubon knew of the bird in New Jersey, but did not know anyone who had observed it in New York. The same was true in Massachusetts and Maine. “On my later northern journeys,” he wrote, “I nowhere saw it. A very few remain and spend the winter in New Jersey and Pennsylvania, where I have seen them only during summer, and where they breed. As we proceed farther south, they become more and more abundant.” In the early twentieth century, Forbush had occasional reports of the Turkey Vulture in New England. Today they are widespread throughout Vermont. Locally. thirty to fifty birds congregate around the Retreat Meadows in Brattleboro from Spring through Fall. In winter, they can be found in southern Connecticut. Although increasingly common in our neighborhood, I know no one who waxes eloquent about their presence.

Occasionally in our history, Turkey Vultures have been protected. In Charleston, South Carolina, Turkey Vultures were relied upon to clean up the offal and waste of the local slaughterhouses. It was a criminal offense to harm one of the birds, and the city officials rigorously enforced the law.

Such is not the case today. Today there is seldom much love expressed toward the Turkey Vulture. Much of the prejudice toward the Turkey Vulture is attributable to its diet - it feeds on carrion. Its diet is often referred to by such terms as filthy, foul, and malodorous. It is a scavenger, gathering where animal waste, scraps and garbage have been discarded.

But why should that be a cause for prejudice and distaste? Lots of birds do the same. Have you never seen crows feeding on a road killed squirrel, chipmunk, or opossum? Gulls are notorious scavengers. Some birders spend hours at town dumps, studying the feeding gulls in search of a rare species, while the gulls pick through the foul-smelling tons of human generated garbage.

A few years ago there was great excitement when an adult Bald Eagle was spotted on the ice in the West River. Traffic along Route 30 was slowed, even stopped, by people trying to get a look at the eagle. The eagle was feeding on a dead deer. Would the same kind of excitement be generated during the summer by vultures feeding on a deer carcass along the river bank? Perhaps if there was a Black Vulture among Turkey Vultures, it might attract the interest of some serious birders. The Black Vulture, a native of our Southeast, is extending its range northward. It is starting to show up in Vermont in the early Spring and mid-Fall. Birders will take notice of a Black Vulture. But the general public? They’ll only be annoyed at having to slow down.

Ah, someone says, the Turkey Vulture is disgusting because it feeds on disgusting, rancid, rotting flesh. If you think that, please read on.

John James Audubon (1785-1851) is synonymous with birds in America. He was a brilliant artist, an inveterate traveler, and a self-promoted frontier woodsman who sported long hair and fir-trimmed buckskins. He was also a superb naturalist with an abiding curiosity. Among the questions he asked was how does the Turkey Vulture find the carrion on which it feeds? By sight? Or smell? To answer the question, he first created a dummy deer carcass filled with straw and laid it in the open. Before long, Turkey Vultures appeared. That answered part of the question. Next he took a hog carcass and hid it under brush in a ravine. Vultures flew overhead but never came down to investigate or feed. Ergo, Turkey Vultures rely on sight, not smell. The authority had spoken.

Unfortunately, Audubon was wrong on two counts. He was wrong in his methodology, and as a result, wrong in his conclusion. In the 1960s, Audubon’s experiment was repeated with a carcass concealed in a box. A small fan blew gently across the carcass. Turkey Vultures soon gathered from many directions downwind and circled the area.

What had Audubon done wrong? The answer did not become clear until further experiments were conducted in the 1980s. Apparently Audubon had used a truly stinking, rotten carcass, presumably reasoning that what he would find odorously offensive would be appealing to Turkey Vultures. Not so. Turkey Vultures like their food properly aged - about one to four days. The Turkey Vultures could smell Audubon’s carcass, but it had the same appeal to them as it would have had to Audubon. None at all. It is now known that Turkey Vultures have a very acute sense of smell. A few straying molecules, often many miles from a carcass, can be detected by Turkey Vultures and lead them to their meal.

Turkey Vultures are one of the few birds which have a good sense of smell. Even their cousins, the Black Vultures, do not have a sense of smell. Black Vultures often travel with Turkey Vultures in order to take advantage of the latter’s ability to smell food. The Blacks follow the TVs to the food source.

So, why is there this prejudice toward the Turkey Vulture? Yes, it eats dead meat, but it is particular about its meat being properly aged, just as I am particular about my dead meat being properly cooked. Most humans eat carrion, though we don’t call it that, and, since we lack the proper beak for the job, we have a butcher cut it up for us. We may have prejudice toward some humans, but except for the odd misanthrope, we are not prejudiced toward all humans. I don’t have an answer for this prejudice toward the vulture, any more than I have an answer for prejudice toward other people - except that all the evidence I seem able to garner suggests that prejudice - avian or human - is ignorance. Which, as a basis for an opinion, is stupid!

Good Birding!

Saturday, November 03, 2007

Vultures Are Storks, Not Hawks

I don’t know anyone who would list the Turkey Vulture among their favorite birds. The Turkey Vulture is big. It is ugly. It has disgusting habits. It feeds entirely on carrion - dead meat, usually thought of as rotten and rancid. The Massachusetts ornithologist, Edward Forbush, described the buzzard (as it is known in folk-circles) as a “cowardly fowl .... They often gather, not only about dead animals, but also about the sick or disabled when death seems imminent. If the death of the victim seems assured they approach their prey. Over what follows let us draw the veil.” He refers to their diet as “filthy cargo,” “foul matter” and “malodorous decaying bodies.” Some four hundred years ago, the habits of vultures gave to our language (according to the Oxford English Dictionary) a noun which could be applied to “a person of vile and rapacious disposition.”

There’s not much in the way of endearing qualities to be found in the vultures.

But ... as masters of the air, the vultures have few equals. The soaring buteos, such as the Red-tailed Hawk, receive good notices as they ride the wind currents. Flocks of people gather on ridges and hill tops when the Broad-winged Hawks are at their peak during Fall migration. The feathered flocks kettle upward on invisible thermals with scarcely a movement of their wings - dozens of birds, in some places hundreds and even thousands - drawing oohs and aahs from the spectators below as they ride the currents, and then stream southward. Few people pay much mind to the nearby Turkey Vultures.

Yet the TVs, as they are cryptically known, could give flying lessons to most of the raptors. They are aloft when the thermals and winds are so weak that the buteos are grounded. With broad wings and a wingspan of five and a half feet, they can capture the faintest of rising thermal and the gentlest of air currents. At four pounds, they are relatively light. They fly with their wings in a “V”, or dihedral. They tip and teeter on their way, like an uncertain tight-rope walker. In heavy winds, they rush through the air, in total control. In the same winds, the smaller hawks are buffeted, and struggle to maintain control of their flight, or perhaps give up entirely and perch until conditions are calmer.

Turkey Vultures, along with the other New World vultures, are popularly grouped with the diurnal raptors - the day hunting birds of prey like the falcons, eagles and hawks. But scientists have long suspected that the relationship may be something very different. New World vultures, for example, have toes which are distinctly different from other birds of prey; the hind toe is small and weak. As such, they cannot carry away their food. When on foot, they are gawky, hopping clumsily. This is very different from the powerful toe and sharp talons of the hawks, which allow them to carry food, but not to walk with any grace.

DNA studies have finally confirmed what scientists have long suspected, with the result that our New World vultures have been reclassified. They are now known to be closely related to storks, and not to any of the hawks nor even the Old World vultures, which are classified in the same order as hawks. Like storks, New World vultures cool their relatively long (and un-hawk-like) legs by defecating on them, which is what gives the vultures the appearance of having white legs. The cooling is affected by the evaporation of the liquid in the feces. (This is yet another of the less appealing characteristics of our vultures.) They also have a vestige of webbing between their toes, suggesting that they once waded in muddy ponds like the storks. Unlike Old World vultures, the New World vultures do not build stick nests, do not have true vocalizations (they lack a syrinx and can only hiss and grunt), and do not nest colonially. The similarities between Old World and New World vultures, such as bald heads, beaks which can tear meat, and regurgitating food to feed young, are the result of what scientists call “convergent evolution.” These adaptations for feeding on carrion evolved independently.

When I lived in Pennsylvania, the pine trees across the street from my home were a roosting place for Turkey Vultures in the late Fall. In the waning afternoon sun, they drifted in from all directions, the low rays turning these big black birds into golden brown. They settled into the tree tops where they were all but invisible, but still wary and skittish. A nearby barking dog might spook them into flight, and then the trees seemed to come alive with the thunderous flapping of wings. In the morning, they perched on the leafless branches of the maples and oaks, their wings open to capture the warmth of the morning sun. Then they lifted off and were gone for the day. Until one day in November day, they did not return at night, and were gone for the season.

A few years ago, I was in southern New Jersey in early November, having wiggled my way into a group of hawk banders who were spending a week as volunteers with the Cape May Bird Observatory’s hawk banding project. Bird movement was quiet when we first settled into the blind in the early morning. But as the fog slowly burned off and the air began to warm, large birds started to rise out of the distant trees. Through the morning, I watched and photographed several kettles of these birds. In mid-September on Putney Mountain I would have known with a certainty that these kettles were flocks of Broad-winged Hawks. But the Broad-wings were long gone to the tropics. The weak rays of the late year sun warmed the air but the warmth was fleeting. Yet the birds in those November kettles circled steadily higher and higher. The rocking of their large, v-shaped wings were subtle adjustments to barely moving air currents and feeble thermals. The Turkey Vultures were moving southward.

A week later at home, I carefully marked the photographs of the Turkey Vulture kettles, so that I would not confuse their black dots with the kettles of Broad-winged Hawks I had photographed in September. Two months separated the buteo kettles and the vulture kettles. The Turkey Vultures can migrate with much less help from the thermals and ridge deflected winds than the broad-wings. They are masters of the aerial currents.

Good Birding.

Saturday, October 20, 2007

Pine Siskins - Vanguard of Winter Finches

Goldfinches in camouflage - that’s how one field guide describes the little brown jobs (LBJs) which have been visiting my feeders in large numbers the last few weeks. The Pine Siskin is almost identical in size and shape to the familiar American Goldfinch. The two species often flock together. From a few yards away, it is very easy to miss the Pine Siskin among the olive drab winter plumage of the goldfinch. A casual glance at the dark wings and wing bars make you think that there is only one species, not two. But then you notice that some of the birds in the flock are buffy and unstreaked on breast and back, and others are very streaked, and you realize that there are two different birds which are consuming your sunflower seeds in such quantity.

Or you may see sparrows and female finches busy on the ground around the feeders; these are the birds that define “little brown job” and are so confusing to many observers. But one of them is hoping on the ground in a way that suggests it is not comfortable scratching among the leaves. Or you notice that it is slimmer than the usually robust looking sparrows. It does not have any prominent head markings, and its beak is sharply pointed. When you finally get your binoculars on this LBJ you might notice that there is yellow along the edge of the wings and tail. You are looking at a Pine Siskin.

Pine Siskins are odd little birds. Forbush summarizes their behavior: “The Northern Pine Siskin is almost as erratic as the crossbills. During every month in the year small flocks wander about as if there were no such thing as a breeding season, and individuals may be seen occasionally in summer far south of their usual breeding-grounds. They may breed one year in a certain region and far away the next, and in migration or in winter they may visit a locality in great numbers in one year and pass it by the next.”

This year they are at my feeders in great numbers, often outnumbering the goldfinches. In my backyard, this is a banner year for the siskins. I have been doing an informal poll of other bird watchers to find out if they are also having large numbers of siskins. At best, they have answered, “A few.” More likely they tell me that one visited once, or a couple occasionally. So far in my polling, Pine Siskins are not being reported in unusual numbers, except in my backyard.

Looking back through my notes, I have managed to see the Pine Siskin every year, but in many of those years, the numbers have been very few. On the other hand, they occasionally hang in large numbers where I happen to be. There is no apparent predictability.

I remember one Spring listening to the finches singing in the trees around my home - jumbled, varied, twittering notes celebrated the melting snow and warming temperatures. Occasionally I scanned the trees and picked out a male American Goldfinch in his fresh yellow plumage. But more often I noticed that the twittering song was interrupted suddenly with a rising “zzshrreeeee,” - then the twittering resumed. Most of those singing finches that early Spring were siskins. Every Spring since, I have listened for the cheerful song that is suddenly interrupted, but have heard it only occasionally.

The American Goldfinch and the Pine Siskin are closely related. Both are classified in the Genus Carduelis, from the Latin for “thistle.” Thistle is presumed to be the favorite food of these birds, and both species have been filling the perches on the thistle feeder in my backyard. The siskins that cannot find a perch contentedly scarf the sunflower seeds in large quantity.

The thistle blooms late in the late summer, and this is sometimes used to explain why the goldfinch is one of the latest nesting bird. Generally, they do not begin to get serious about their breeding responsibilities until late June or early July. I remember years ago finding an occupied goldfinch nest in an apple tree in late September. Presumably the goldfinches postpone their nesting until their favorite food becomes available.

But life in nature is never quite that neat and simple. The Pine Siskin, also a “thistle bird,” begins its breeding season in late March or early April. For such a small bird, it builds a relatively large nest, lined with hair, fur, feathers, and other fine materials. It may be that this fine lining serves as insulation against the harsh weather still common in the northern latitude pine forests where the Pine Siskin nests. One study suggests that they feed their young mainly on aphids, and another study has shown that various insects figure prominently in their diet. This is only what would be expected, especially during the rearing of young with their heavy protein requirements. In nesting early, the siskins are relying on the insects which also emerge early in the year.

Pine Siskins wander widely in the pine forests of the north, and as a consequence, there is much about these birds that is still uncertain. Bent, in his 1968 Life History, is uncertain whether they double-brood. Thirty years later, Baicich and Harrison still can only say, “Possibly double-brooded.” Siskins follow their own time-table. I am quite sure that they understand when and where they breed, but science is still trying to puzzle it out.

This year I saw my first Pine Siskins on a mountain top in mid June. I don’t know where they were in their breeding cycle - at the end, or just beginning, or starting over again. That they were breeding on the mountain top, I am sure. They prefer the northern pine forest, and that habitat stretches south along our mountain tops.

Once breeding is concluded, the siskins move southward in a pattern that is completely unpredictable. In our neighborhood, southward may mean nothing more than moving from higher elevations to lower elevations. When the first siskins started showing up in my backyard in early August, they were probably the mountain top birds coming down to the valleys.

What about the siskins covering the thistle feeder perches now? When I reported this to another birder, his response was, “This could be a good finch year.” Every so often, the northern finches irrupt southward. Poor seed crops in northern Ontario have led some field ornithologists to predict that this will be an irruptive year. So my siskins may be the vanguard of the winder finches.

The Common Redpoll (also Genus Carduelis) is fairly predictable; it usually appears in the northeast every other year. The Pine Grosbeak is less predictable. It has not been reported on a Christmas Count for several years. Many feel it is due. And the crossbills - they are about as erratic as any of these finch family birds. A report of large numbers of siskins at backyard feeders is grasped by some as a harbinger of winter finch sightings to come. I know one birder who is already twitching at the possibility.

The Pine Siskins in my backyard may be a vanguard - or just an anomaly. We’ll see. Sometimes, good birding is defined by hope and anticipation. But I hope that winter birding this year will be defined by many winter finches. I hope that is what the Pine Siskins in my yard are anticipating. I hope.

Good birding.

Monday, October 15, 2007

Pine Siskins

Pine Siskins have irrupted in my backyard. For a couple of weeks, an estimated 20-30 siskins have been regular at the feeders, often outnumbering the goldfinches with which they seem to be flocking. I've only seen a scattering of reports about siskins elsewhere, but maybe (I hope) this is the first sign of a winter finches this year.

Saturday, October 06, 2007

I couldn't find photos which suited this week's column, but decided to put up a couple anyway. Swamp Sparrow behaving like a wren - and a visitor to my new window feeder. Please don't miss the unillustrated column below.

Some Curiosities in Bird Names

Bird names are often curious. The rules of nomenclature say that once a bird has been named, it keeps that name, even if the name has no bearing on what is subsequently learned about the bird. That explains why, for example, the robin has never been renamed the reb-breasted thrush but remains the (American) robin, because it bears a similarity to the (Eurasian) robin which has a red breast. Or why the American Redstart does not have warbler in its name in some fashion, because it bears a superficial resemblance to European redstarts, all of which are in the thrush family.

A curious aspect about bird names is that many of the common birds which we know in the East are descriptive names, while many of the birds found in the West belong to someone; they are so and so’s bird.

Consider our eastern warblers. In the East we find the yellow, chestnut-sided, black and white, black-throated green, black-throated blue, blue-winged, cerulean, bay-breasted, and others. If not descriptive of the bird, the name may suggest their diet or where they are found: myrtle (now yellow-rumped), worm-eating, magnolia, and pine. By contrast, among the western warblers we find Virginia’s, Lucy’s, Townsend’s, Grace’s, MacGillivray’s, and Audubon’s (now lumped with the myrtle as the yellow-rumped).

The names of our eastern sparrow, all nondescript little brown birds, are descriptive. Chipping Sparrows chip, Song Sparrows sing, Field Sparrows are found in fields, Swamp Sparrows in swamps, White-throated Sparrows have white throats, and White-crowned Sparrows have white crowns. Go out West and you will find sparrows that also have descriptive names (sage, or rufous-crowned), but you will also find sparrows that “belong” to Botteri, Cassin, Brewer, Baird, Harris and Le Conte.

Not a single one of our local woodpeckers has a proper name in its name (downy, hairy, red-bellied, pileated, flicker, yellow-bellied sapsucker), but in the West you will find Lewis’s and Nuttall’s Woodpeckers and Williamson’s Sapsucker.

The Ruby-throated Hummingbird is the only regularly occurring hummingbird in the East; other species occasionally show up, especially in the Fall, but they are usually juveniles and are notoriously difficult to identify as a different species, even for many very experienced birders. In the West you can find many species of hummingbirds and most have names descriptive of their plumage. But among those western hummingbirds there is also Anna’s, Costa’s, and Allen’s.

In the East, many common birds have a slue of folk names, a situation which often caused confusion until the American Ornithological Union began imposing some order. I pick just a few by way of example. The Northern Flicker has been known as High-hole; Wake-up; Harrywicket, and Yellow Hammer. The Chipping Sparrow has been called Chip-bird and Hair-bird and is still referred to as Chippy. The Common Yellowthroat is still, and will continue to be, called the “Wichety-wichety,” and no amount of officialdom is likely to change that.

So why does the West have so many birds named for forgotten people? It goes back to the history of Europeans in North America. The Spanish came to the Western Hemisphere for gold; the French came for furs. The English came to stay. It was the early 1800s before curious naturalists began describing the flora and fauna of North America in any serious or systematic way. Alexander Wilson, considered the father of American ornithology, and John James Audubon, were self-taught artists and naturalists, often pursuing their interests in neglect of making a living. By the time they began their work, people of European descent, mostly English, had been living in the eastern states for two hundred years. They were clearing the forests, struggling with the native peoples they were displacing, contending with a far-away monarch, and creating a new form of government. In the course of making a living, they noticed the potato bird which ate the bugs in their garden (Rose-breasted Grosbeak). They scattered the rice-birds eating their rice with bird-shot (Bobolinks). They enjoyed partridge (Ruffed Grouse) and gobbler (Wild Turkey) on the dinner plate. And they listened to Stake-driver, Thunder-pumper, and Dunk-a-doo in the marshes (American Bittern). When the naturalists went to work describing the birds of the East, many of those birds were already very familiar. The naturalists provided some system and order.

At the beginning of the 1800s, President Jefferson pulled off the greatest land purchase in history, but had no idea what he had bought. The Lewis and Clark Expedition was the first of many organized excursions by the English-speaking Americans to discover what lay westward. These expeditions were all sent out with instructions to record the plants, animals, birds, geography, and people to be found in these new lands. Accompanying the expeditions were naturalists (albeit often self-trained naturalists) charged with fulfilling these instructions. Hundreds of new species were recorded and collected, and eventually found their way back to the East. This continued as the frontier pushed its way to the Pacific coast and exploratory expeditions gave way to permanent settlers. Western species were new to everyone. With no folk names, the naturalists were free to do the naming.

Modern science was still in its developmental stage in the early nineteenth century, but already it was well-established that the person who discovered a new species - that is, described a new species for science - had the right to name it, and the name would continue thereafter. It was not appropriate to name a species after oneself, but you could honor someone by giving that person’s name to a species you discovered. Audubon, for example, named a rare eastern warbler (non extinct) and sparrow after his South Carolina friend, Dr. John Bachman. Other Audubon friends and companions were honored in Harris’ Sparrow and Harlan’s Hawk (now a sub-species of the Red-tailed Hawk). It fell to others to honor the pioneers of American ornithology. Alexander Wilson fared quite well; his name is attached to a warbler, plover, snipe, and storm-petrel, and also to a genus of warbler. Audubon did not fare quite so well. An Atlantic shearwater is named for Audubon, and the western warbler which is now a sub-species of the Yellow-rumped Warbler. The western species called so and so’s, were discovered and described by various naturalists and named by them, often honoring someone.

Eastern species which are named for a person are typically unusual or rare species; they were not well known to the general population and therefore could be discovered and named (Kirkland’s Warbler, for example). In the East, birds bearing a place name, like Cape May, Tennessee, Connecticut or Nashville Warblers recall the place where they were first “discovered,” not where they live. The four warblers just named winter in the tropics and breed near or north of the Canadian border. They merely pass through their place names during migration. On the other hand, western birds named for a place are likely to be residents of the place, like California Thrasher, California Quail, and Arizona Woodpecker (previously known as Strickland’s Woodpecker).

I haven’t begun to exhaust this topic of bird names, but I have run out of space for this week. Good birding!

Saturday, September 29, 2007

Nuthatches - Agile Acrobats on the Tree Trunk

Just when I think I have gotten a bird nicely figured out, I see one of its kind do something completely out of character. This time, it was the nuthatches, and specifically, the Red-breasted Nuthatch.

Nuthatches are stubby, stocky little birds with short tails; they have strong legs and feet, and long toes with sharp claws. These are all adaptations for life on a tree trunk, a niche they share with woodpeckers and the Brown Creeper. Their body style bears a superficial resemblance to these other arboreal species, but that is as close as their relationship comes - superficial. Nuthatches parted evolutionary company with the woodpeckers long ago. The somewhat similar traits in a similar habitat are the result of what scientists call “convergence.”

The woodpeckers and the creeper, supported by their stiff tail feathers, climb up a tree trunk. The nuthatches also climb up the tree trunk, but they are just as likely to climb down the tree trunk head first. The tree trunk, and the tree branches, are where the nuthatches earn their living. They forage for insects and assorted invertebrates in the bark crevices. Their short tail enables them to move as easily down as they do up. By contrast, the longer tail of the woodpeckers would get in their way if they tried to move downward.

Science has not been able to figure out why nuthatches climb down a tree. Research seems to suggest that it is more efficient to forage in the manner of the woodpeckers and creepers - fly to a low spot on the trunk and then move upward. Perhaps the nuthatches are able to see prey when they are moving down that the upward feeders miss.

The natural habitat of the nuthatches is mature forest. The White-breasted Nuthatch will make its home in the broken “forest” between river and farm field, or in a town or village, providing the “forest” has large trees. The Red-breasted Nuthatch prefers mature coniferous forests. With suitable habitat nearby, these nuthatches will often forage for seeds at bird feeders where sunflower seeds are their preferred choice.

Bent’s Life History calls the White-breasted Nuthatch droll, earnest, sedate, and lacking in a sense of humor. Adjectives applied to the Red-breasted include happy, jolly, quick and agile. I rather prefer “acrobatic clown” for the White-breasted; it perches on the feeder, upside down, with head extended at a right angle from its body, daring any chiropractor to set its spine straight. The smaller Red-breasted may be jolly, but it is also feisty, sometimes aggressive toward larger birds. “Irrepressible woodland gnome” is appropriate even when the Red-breasted ventures out of the woodlands and to our feeders.

That the nuthatches are feeder birds tells you that their diet is varied. They may be adapted to foraging on tree trunks for invertebrate protein, but vegetable matter in the form of nutrition rich seeds is prevalent in their diet. Seeds and small nuts give them their name, “nuthatch.” At our feeders, nuthatches are like chickadees and titmice; they grab a sunflower seed and fly off to crack it open. Chickadees and titmice hold the seed between their feet and pound it open with their bill. Nuthatches, by contrast, take a sunflower seed, fly to a tree, and jam the seed into a crevice. Then they pound it open with their bill to release the nutritious kernel.

Nuthatches have been finding food in this manner long before we started putting out bird feeders. We watch them forage from the warm comfort of our homes, which, you must admit, is a very indolent way to observe nature. When observation of nature required walking in the woods (or more likely - working, hunting, harvesting, and foraging), the nuthatch was frequently seen hacking open seeds or small nuts with its bill. Hence its name: nuthatch. “Nut” from its food - probably nothing so large as a hickory nut or walnut, but a small pod which contained seed ... and “hatch,” which is an earlier form of “hack,” from its practice of hacking a seed too large to swallow whole into small pieces.

This hatching requires certain physical adaptations similar to those of the woodpecker - a sturdy bill and muscle strength for pounding. This in turn allows most nuthatches worldwide (there are 25 species) to excavate a nest cavity. The Red-breasted Nuthatch excavates a cavity, and often smears sticky pitch around the entrance hole, probably to discourage other creatures from entering. Our White-breasted Nuthatch is an exception; it uses existing cavities.

Nuthatches are one of the few birds that use a tool. Some will hold a piece of bark and look for food by flaking off other pieces of bark.

So that summarizes the adaptation of the nuthatches to life on the trunks and branches of mature forest trees. These intelligent and agile little birds make their living by acrobatically gleaning invertebrates and gathering seeds and nuts from their arboreal home. They are not aerialists; they fly, awkwardly it often seems, from one food source to another.

A week ago, I was in a stand of pines on the edge of a coastal marsh looking for shorebirds. The tide was out, so the shorebirds had gone to the rich mud of the tidal estuary and I had to notice other things. What I noticed was a flycatcher sallying from the pines, making a quick circle over the marsh grasses, and returning to the pines. I had glimpsed a tail-wagging phoebe and assumed that the flycatching bird was a phoebe doing what it is designed to do. In the absence of shorebirds to watch, I decided a good look at a phoebe would be in order. I continued to watch the swooping flycatcher bird until I finally saw it return to an overhead branch. But the bird had no tail and instead of perching upright, it clung to the side of the branch. I thought I had missed the return of the flycatching phoebe. Everything about the bird I was looking at said Red-breasted Nuthatch, including the repeated, thin notes: “eeeen, eeeen, eeeen.” It stayed still long enough for me to focus my binoculars.

Then the Red-breasted Nuthatch flew out over the marsh grasses in a quick circle and returned to the pines. Over and over and over it sallied through swarms of insects. Once it alighted, and paused, so that I could see in its beak the insect which it had adeptly snatched in mid-air.

My first thought was - the Red-breasted is not adapted to flycatching. But then I realized that the most important adaptation for the Red-breasted, or any species, is the ability to adapt. The flycatching Red-breasted saw those swarms of rich protein over the grasses and exploited their availability. It did not care that it had not evolved as a flycatcher. Back on the branch, it clung acrobatically upside down while it ate its fly.

Good Birding!

Wednesday, September 26, 2007

Plum Island

A recent trip to Parker River NWR (Plum Island) near Newburyport, MA, on the coast produced Buff-breasted Sandpiper, American Golden Plover, Baird's Sandpiper, and Stilt Sandpiper, all relatively rare, and among the shorebirds, something of an identification challenge. Unfortunately, they were also beyond good photography range. Here are a few that were within range for photography.
(BTW and FYI, I use a Sony DSC-H5 with 7.2 megapixels and 12X optical zoom)

Saturday, September 22, 2007

The Osprey - a Unique Bird of Prey

The e-mailer was driving along Route 142 near the Connecticut River when she saw a bird just above the water. She wrote: “This bird was big! Very light, mottled feathers, mostly white, but what really caught my eye was the distinctive black eye ‘patch’. As I watched, the bird made a very tight circle, folded it's wings, and dove straight into the water! It flew back out, apparently unsuccessful, because I did not see anything in it's talons.”

She saw an Osprey, also known as the Fish Hawk. With its recovery from the devastation caused by DDT, the Osprey is again a common bird along the New England coast, and may be seen anywhere in Vermont where there is water - along our rivers, lakes, and large ponds.

The Osprey’s diet is almost exclusively fish, and from what I have been able to determine, almost exclusively fresh fish. It hovers 30-100 feet above the water surface looking for fish near the surface. Finding its prey, it plunges to the water, sometimes completely submerging save for wing tips. Terres in Encyclopedia of North American Birds completes the description of the Osprey’s fishing: “Rises from water with fish gripped in both feet, pauses in midair to shake water from plumage, and to arrange fish with head pointed forward, which reduces its resistance to air, flies with it to habitual perch to eat or to nest to feed young. Reported to carry fish up to 4lbs or more.” This dull description only hints at the excitement generated when you are able to watch the real thing.

The Osprey is the only bird which fishes in this manner. Gulls plop on the surface. Many aerial sea birds, like pelicans or gannets, plunge dive, capturing fish in their beaks. The Bald Eagle, also a “fish hawk,” plucks fish near the surface with its talons.

The Osprey and the Bald Eagle pose interesting contrasts. The Osprey rarely eats dead fish; the Bald Eagle enjoys dead fish, and dead anything else. The Osprey is a tireless fisher. It will consume its catch, then go hunting for more. The Bald Eagle does as little work as possible. When in the mood for fresh meat, rather than carrion, it is content to let the Osprey catch a fish and then steal it.

An older naturalist, like Edward Forbush, always wrote of the benefit or harm that a particular bird posed to humans. In contrast to many other hawks, Forbush could write of the Osprey that all “the evidence available points to the conclusion that the Osprey is harmless to poultry, birds and game, and that most of the fish that it takes are species of little value to mankind. Fishermen usually welcome it as a guide to good fishing. All things considered, this great, handsome, picturesque and interesting bird must be regarded as a subject for perpetual protection.”

In the nineteenth and early twentieth centuries, an even greater contrast in attitude was found among coastal farmers. Where most people in those times considered hawks vermin to be exterminated (most hawks, given the opportunity, would take a barnyard chicken), coastal farmers and fishermen actively protected Osprey. They watched Ospreys aggressively protecting their nests, eggs, and young. The farmers’ young chickens ran free during the summer; it was assumed that the Osprey protected the chickens from other hawks. Coastal farmers were anxious to have Osprey nesting close to their farmyard, so they set up nesting platforms for them - a tall pole with a wheel fixed on its top.

However, John James Audubon was the more complete observer of the Osprey. In the mid-nineteenth century he described the Osprey, or Fish Hawk as he knew it, as having a mild disposition: “Not only do these birds live in perfect harmony together, but they even allow other birds of very different character to approach so near to them as to build their nests of the very materials of which the outer parts of their own are constructed. I have never observed a Fish Hawk chasing any other bird whatever.”

He also debunks the coastal farmers belief that the Osprey protected the barnyard chickens from other hawks. Rather than staying away from the Ospreys, the other hawks simply went away; they went inland “for the purpose of rearing their young in security.” When the shorebirds and waterfowl returned to the coastal marshes, the other hawks returned as well. By then, the Osprey had completed its nesting and had begun moving south.

The Osprey is one of the most widely distributed birds in the world, found on every continent in the world except Antarctica and even on some remote Pacific Islands. In the western hemisphere it nests in North America; northern populations migrate to warmer climates for the winter.

The Osprey is a unique bird of prey. It belongs to the Order: Falconiformes - the diurnal birds of prey. But the Osprey has been on its own evolutionary path for a long time. Taxonomic classification constantly changes. At one time the Osprey was in a Family by itself; the other Families being Hawk Family and Falcon Family. Current classification puts it in a sub-Family of the Hawk Family, making it a little more closely related to the hawks and eagles than to the falcons, but not by much. It is the only member of its sub-Family.

The point is, there are things about the Osprey that are unique among the diurnal birds of prey. For example, the Osprey has long, strong claws, curved about one-third of a circle. The claws are round. The toes are equal length. The lower surface of the toes are covered with spicules (small, bony spines) which help hold slippery fish. The outer toe is reversible (like an owls’) so that it can hold prey with two toes in front and two in back. Its plumage is compact which reduces wetting when it plunges into the water. These are only some features of the Osprey which make it unique among the hawks.

The scientific name for the Osprey is Pandion haliaetus. The genus name refers to the complicated Greek legend of Pandion, king of Athens, and his two daughters. The rules of taxonomic nomenclature require that once a name has been applied, we are stuck with it, even if it is wrong. This is one of those cases; there is no reasonable, or even unreasonable, reason for applying the name “Pandion” to the Osprey. The best that can be said, is that this was a flight of mythological exuberance. The species name, haliaetus, does a little better; it means “sea eagle” from the Greek.

How the name “Osprey” came to be applied to this “Fish Hawk” is a mystery. “Osprey” probably derives from the Latin, meaning something like “bone breaker.” The original “bone-breaker” known to the Romans was the Lammergeier, or “lamb vulture,” which dropped bones from a height in order to break them. No one seems to know how “osprey” came to be applied to the bird we know. However, translators of the King James Version (1611) do refer to “the eagle, the ossifrage, and the ospray.” An early commentator on this translation explains that the ossifrage is a “species of eagle” and the osprey is “the black eagle.” Clearly these theologians were a bit confused, especially since Shakespeare a few years earlier had written (correctly) in Coriolanus: “As is the osprey to the fish, who takes it by sovereignty of nature.” This suggests that for reliable observations of the natural world, you may be better served by a poet than by a theologian.

Good birding!

Saturday, September 15, 2007

The Osprey - a Favorite with Hawk Watchers

Migration is underway. If the weather has cleared by the time this column appears, the Broad-winged Hawk numbers crossing the Putney Mountain ridge should be at their peak, with potential numbers in the hundreds in a day. The small band of hawk watchers began trekking to the clearing along the ridge line at the beginning of September. They do an actual count of the migrating hawks; the count numbers are sent to a national data base and become fodder for researchers.

The “count” provides an excuse for this quirky sub-group of birdwatchers to pursue their fascination with hawks, and in particular, with the challenging art of identifying hawks in flight. Most bird identification by birdwatchers involves observation of field marks, recognition of plumage, and association of size, shape, and feeding habits with a particular species. But hawks in flight are high overhead, often only a dark profile against the sky. Watching that dark profile as it flaps, or glides, or soars, or stoops and attaching those distant observations to a particular species, is an art. Join the watchers on Putney Mountain and listen as they discuss the identity of a passing hawk, and you will realize that it is an imprecise art. For some, it is also an art that is addictive.

But my interest today is not the hawk watchers, but the hawks - and one in particular: the Osprey. In a typical year, a couple hundred Ospreys may be counted by the Putney Mountain hawk watchers, so it is not an uncommon bird. Even so, the Osprey always creates a buzz as it approaches and passes over, diverting attention from any other hawks which may be visible at the same time. Only an eagle - the less common Bald or very rare Golden - creates a greater buzz and diverts attention for longer.

The Peregrine Falcon also generates excitement, but the Peregrine is likely to pass quickly, as though it has a deadline to meet. Not so the Osprey. It flies steadily and with purpose. It is large, twenty-three inches in length and with a wing-span of sixty-three inches. Among the hawks of the Northeast, only the eagles are larger. The Osprey’s size neutralizes wind and weather. Strong winds buffet small hawks, like the Sharp-shinned or kestrel, bouncing them on the currents, pushing them along like a red maple leaf loose in the air. Not so the Osprey. It flies steady, seemingly oblivious to even the heaviest winds, yet deftly employing those winds to travel with minimum expense, seldom flapping, merely adjusting a wing set or a tail angle for full advantage.

Moreover, the Osprey is likely to travel in all manner of weather. Cloud cover, heavy and low, grounds most hawks. But the Osprey, always born near water, is a habitue of lakes, of ocean coasts with rolling fog banks, and river valleys where morning fog lies heavily long after sunrise. A bit of cloud cover is no deterrent to this master of the gray skies.

That’s not say that the Osprey cannot soar. It can and does soar. Give it a rising thermal on a sunny mid-day, and the Osprey will circle quickly and effortlessly upward, joining the dozens of Broad-winged Hawks that rely on those thermals during their long migration to the tropics.

When still a dark spot in the sky, hawk watchers are likely to announce the Osprey’s approach. The wing set is their clue. The Osprey looks like a large flying capital “M.” A more technical description is that Osprey’s wings are held above the horizontal with a sharp downward bend at the wrist. Some writers also caution that this wing set can be confused with the wing set of gulls; they caution that the Osprey is the hawk that looks like a gull but is not. If I had not read that an Osprey could be confused with a gull, I would not have known that. Gulls may fly with wings that look like a capital “M,” but they almost always flap their wings. Ospreys over Putney Mountain don’t flap. (At least, they don’t flap like the occasional passing gull.)

The Osprey’s charisma lies in its size, in the steadiness and surety with which it flies, and in the command it exercises of wind and weather. Its charisma may also derive from its sheer presence and relative commonness. Not too many years ago, the Osprey was severely endangered. The pesticide, DDT, worked its way through the food chain, concentrating in the prey species at the top of the food chain - in the Osprey’s case, the fish on which it fed. DDT thinned the egg shells, the end result of which was widespread nesting failure. When DDT was banned, the Osprey began to recover, aided by many recovery efforts. Nesting platforms all along seacoasts, lakes and rivers are the most visible evidence of those recovery efforts which also included rigorous protections, and often hacking programs. Hacking programs involve taking a chick from a distant area, and raising it with surrogate parents (usually underpaid biology students). The success of these programs with Ospreys was probably helped by the fact that Ospreys are genetically programmed to hunt in the Osprey manner; they do not have to be taught by the parents. When the young are able to fly, they begin to fish.

The Osprey has recovered. Especially along the coasts, it is considered common. In southeasternVermont you may see it along the Connecticut or West Rivers from late-March to early November. Many pairs nest near Lake Champlain. I have seen Osprey over Grout Pond, Somerset and Harriman Reservoirs. And of course, during “hawk watch season” on Putney Mountain, they are regular.

The hawk watchers have a rule of thumb that when one Osprey is seen, five minutes later another will be appear. I would not want to subject this rule to a rigorous scientific testing, but it is generally true that the Osprey is an unusually gregarious hawk and travels with others of its kind. John James Audubon often saw flocks of eight or ten Ospreys migrating together along the coast.

Ospreys are also likely to nest in proximity to other Ospreys. In the early twentieth century, Forbush knew of a colony on Narranganset Bay with about seventy-five active nests. In protected coastal areas today where nesting platforms have been erected, it is common to see multiple Osprey nests. Ospreys seem to be able to get along with their neighbors, a characteristic that is not very common in the natural world - nor, for that matter, in the civilized world. Given this characteristic, it is not so surprising that the Ospreys will migrate together, sometimes at five minute intervals.

Of course, many hawks are seen with their kind during migration. Sharp-shinned Hawks often travel together, but as any hawk watcher will tell you, they don’t travel together in peace. Sharpies are constantly in dog-fights with one another, or any other hawk or eagle that may presume to share air space with them. Broad-winged Hawks migrate by the dozens, and sometimes hundreds, and further south by the thousands and tens of thousands. They congregate where the thermals are rising; they watch for distant kettles of broadies to locate the next thermal on the route. But once in the tropics, they disperse widely and singly to spend the winter.

Ospreys don’t seem to need their kind to get along, but they seem to get along with their own kind. I can think of worst ways to live one’s life. I’ll probably have more on the Osprey in the future, but for the moment, the rain has stopped, the sky is clearing, and I’d rather go look at hawks than write about them. And that dark spot in the sky that looks like the “Arches” with the gold turned off - that’s an Osprey. Good birding.


Related Posts with Thumbnails