Saturday, March 29, 2008

Blackbirds Are Songbirds That Can’t Sing

Some of the blackbirds are among the earliest songbirds to return to our Vermont neighborhoods. The blackbirds which return early are members of the blackbird family (Icteridae), and they are mostly black: Red-winged Blackbird, Common Grackle, Brown-headed Cowbird, and the uncommon, bog-loving Rusty Blackbird. Other black birds, such as starlings, crows, and ravens, are not blackbirds (Icteridae). They belong to the same Order (Passeri - songbirds), but different families.

So ... not all black birds are blackbirds, and not all blackbirds are black. The Icteridae family includes meadowlarks, bobolinks, and orioles. These blackbird family members are among the most beautiful summer birds with some of the sweetest songs, songs that send a shiver through the body. Baltimore Orioles, brilliant orange and black, sing from tree tops. In pastures and grasslands, the Bobolink’s bubbly whistles carry over the fields, perhaps joined by the (now rare in Vermont) Eastern Meadowlark’s “spring-of-the-year.”

But these colorful blackbird songsters will not return for several weeks yet. The blackbirds which have returned are the black birds.

And yes, I have started out by having some deliberate fun with common names. Common names are often confusing because they are more likely to be descriptive than to explain relationships. Just to throw one more piece into the confusing stew, in Europe there is the Common Blackbird; its profile and structure makes it look like a black robin. That is what it is; in Europe the blackbird is a thrush like our robin.

The blackbird family (Icteridae) is found only in the Americas. Many of them are black, and those black blackbirds are among the first songbirds to return in the Spring - the red-wings, cowbirds, and grackles. Birders welcome them because they are the promise of Spring, the vanguard of what is soon to come. After our long winter months in Vermont, they finally give us something new to look at and listen to.

I have been watching these blackbirds at my feeders. They are wary and skittish. The slightest inside movement sends them flying off. When I walk outside, I see their dark silhouettes high in the bare branches. They are beginning their courtship, and singing - if you can call it that.

Consider, for example, the Common Grackle: I suppose the song of the grackle is exciting to the females he is courting, and it may even be intimidating or threatening to another, less adept, male grackle. They get plenty of practice; they are singing constantly, always with enthusiasm and energy. But don’t expect the Common Grackle to appear on any list of Grammy nominated musicians; their songs are anything but harmonious (which would not necessarily exclude them from the Grammys), and often sound like a stack of discordant noise in an otherwise bucolic setting. Pete Dunne has described their vocalizations as “Noisy! Song is loud and harsh - a gutteral protest followed by a breathy, strangled screech.”

Massachusetts ornithologist Edward Forbush described Common Grackle’s song this way: “The outpourings of a flock of these birds have been likened to a ‘wheelbarrow chorus,’ but the sound might be better represented by a number of iron gates swinging, creaking and clanging on rusty un-oiled hinges.”

Forbush continues: “That this vocal performance should be classed as a song from a scientific point of view there is no doubt, but such it would not seem to the ordinary observer. It is harsh and disagreeable, a squeaking, saw-filling explosion of notes. It varies considerably and sometimes suggests the sound of a jet of escaping steam. I have written it down ‘er wheet, dam that,’ but my interpretation may have been influenced by my mental attitude induced by the performance.”

The Red-winged Blackbird and the Brown-headed Cowbird aren’t much better at singing than the Common Grackle, but they have not been subjected to the derisive descriptions that their cousin endures. Dunne, for example, describes the male red-wing’s classic song as “a loud musically gurgled ‘tur-a-leeee.’” Kaufman calls the song a “nasal gurgling ending in rough trill.” And Forbush, noting that the Red-wing loves the marsh and waterside, describes its notes as carrying “a suggestion of boggy ooze, and that its “chuck” is frog-like. The classic mnemonic for the Red-winged Blackbird is “conk-a-reee;” the extended long “e” in the mnemonic has a musical tone that I have never seen applied to any vocalization of the Common Grackle.

Likewise, the Brown-headed Cowbird seems to have been overlooked by the music critics, although its lack of singing ability is about the only thing that critics have overlooked. This is a bird that bird lovers love to hate. It is a brood parasite; the female drops her eggs in the nests of other songbirds, usually smaller ones, and leaves all incubating and raising to the host birds. Cowbird parasitism is a significant problem for many of our favorite songbirds. In addition, the cowbird is ugly: the male all black with a dark brown head - the female a dirty gray brown.

Since musical criticism of the cowbird’s song has so far been overlooked, I’ll weigh in. Kaufman describes the song as low gurgles and high thin notes; Forbush renders the song as a “squeaky, bubbly “glug-glug-gleeee.” Pause in your reading and repeat that phrase out loud over and over: “glug-glug-gleeee ... glug-glug-gleeee ... glug-glug-gleeee.” Now, dear reader, if you tell me that this is a beautiful song, then I must reply that you have abysmal taste in music and/or you are more tone deaf than I am.

The blackbirds (the black ones) are songbirds by taxonomic classification, not by their vocal abilities. Nevertheless, I welcome their songs, such as they are. In March when winter is releasing its grip with great reluctance, they bring a sound that is filled with enthusiasm, energy, and hope. Our three common blackbirds (I could do with the cowbird being less common) are the vanguard of a great wave that is moving northward, carried on nature’s irrepressible impulse for life. The blackbirds are decked out in fresh, iridescent plumage. They are active and energetic. Noisy and gregarious. The very things we need to awaken us after our semi-hibernation and winter dormancy.

Like the squeaking of an oil-less wheelbarrow, the grackles are singing. I hear them through the storm windows. Outside I see them in the tree tops. The noisy songs speak of Spring and the thought of Spring makes me wonder what other signs there might be. So I wade through the softening snow pack. Beneath a tree where the ground is bare, tiger lilies are beginning to emerge. In the southern corner by the chimney, crocus are growing, beginning to bud.

To my friend in the tree top I say, “You’re right - Spring is near.” The grackle’s un-oiled wheelbarrow creaks loudly. It is one of nature’s sounds welcome sounds. Good birding!

Saturday, March 15, 2008

Killdeer - A Delightfully Noisy Plover

Last week a single, matter-of-fact report got me thinking about a common shorebird that most of us take for granted, and shouldn’t. It is easily identified, easily heard, can be seen anywhere in North America except the far north. It likes open country, lake shores, rivers, plowed fields, pastures, large lawns, and gravel parking lots. The report: a single Killdeer was observed running across the snow at the country club.

The Killdeer is a member of the Plover family and is most closely related to small plovers such as the common Semipalmated Plover and the endangered Piping Plover. All belong to the Genus, Charadius, which derives from a Greek word meaning “gully.” The reference is to the nest of the Killdeer and its close relatives. Generally the Killdeer makes a tiny hollow (“gully”) for its eggs, perhaps with a few chips of stone or woods, or weed stalks placed around it. There is no great time, expense, effort, or creativity put into the nest. The Killdeer nests that I have seen required some imagination in order to claim that the Killdeer had built it; the building was minimal at best.

Last year I saw several nesting Killdeer in a gravel parking area at a ski area. It has been suggested that nesting in such an open area gives the Killdeer an extended view so that it can quickly react to an intruder or potential danger. When any perceived threat appears, the Killdeer immediately begins its defensive maneuvers to protect its eggs or its young.

I remember one time walking through a farmer’s pasture in mid-May when I heard loud, shrill “kill-dee, kill-dee, kill-dee.” The panicked distress call went on and on, and drew my attention. There was a Killdeer, orange tail spread, limping along with an injured wing. Had I been a big, enthusiastic bird-dog, I would have gone bounding after the poor distressed bird, delighted that I could grab it so easily and proudly present it to my master. And I would have ended up with a great big mouthful of nothing. The broken wing and the shrill distressed “kill-dee, kill-dee, kill-dee” is just an act, designed to draw away the gullible intruder.

But I wasn’t a big, gullible dog, and I was wise to the Killdeer. I watched it limping off in one direction. To provide some reassurance to the poor Killdeer, I followed it for a few paces. But then I turned around and saw four downy young Killdeer, just a few days out of the egg. They scurried through the grass into cover, while their other parent flew about, screaming and providing additional distraction from the young.

Meanwhile, the faux-injured bird kept itself safe; its injured wing healed miraculously, and it flew off well before I could have become a real threat or the most rambunctious bird-dog could have made a grab.

The Killdeer employs different defensive tactics in different circumstances. Bent’s Life History reports an observer who noticed that a flock of driven goats divided in the middle of a field: “I walked up to the place expecting to find a rattlesnake, and found instead a killdeer standing over her eggs with upspread wings and scolding vigorously.”

Another observer watched a Killdeer family along the shore of a pond. Shorebirds were abundant around the pond except in the vicinity of the parent killdeer: “The parent was extremely belligerent, and I watched it attack other killdeers, yellowlegs, spotted sandpipers, soras, and song sparrows that happened to wander in the vicinity. All birds seemed glad to leave the vicinity.”

Much of the Killdeer’s defensive pugnacity is vocal, but its oft repeated “kill-dee, kill-dee, kill-dee” is not limited to times of danger, though danger makes the cry more strident. The Killdeer is the noisy plover, as one writer calls it in English and as science names it in Latin. Charadius vociferus scarcely needs translation; the Killdeer is vociferous - loud, clamorous, noisy. Often I hear the Killdeer before I see it. It calls when it takes flight. It calls when it is in flight. It calls whenever it feels in the mood, which is often.

The Killdeer seen last week on top of the snow is not unusual. It is an early migrant. Birds begin their northward journeys when the amount of daylight and their internal clocks say it is time to go. These triggers to movement do not necessarily coincide with propitious weather.

I remember a few years ago when we also had deep snows. The fields around the water treatment plant on Route 30 had a few bare patches and along the highway berm the ground was clear. But most of the pastures were still covered with snow. Dozens of killdeer were concentrated along the bare roadside and the small areas free from snow, while many also worked their way along the top of the snow. They all moved in classic plover fashion - walk, halt, stop-and-pick, walk, halt, stop-and-pick, their movements abrupt and jerky.

The Killdeer is so widespread and so common that it is easy for birders to be dismissive: “Oh, it’s just a Killdeer” - then hurry on to look for something “good.” There is nothing difficult about identifying the Killdeer. It is distinctive and unmistakable. Some birders have thick masochistic streaks; they are not truly happy unless they are painfully trying to make a difficult identification, and the Killdeer doesn’t even have any subspecies to challenge them.

But I find the Killdeer to be a joyful bird, one that is always a pleasure to see. It is handsome, active, often entertaining. It is one of the easier birds to identify in flight or by its call.

And the Killdeer can become quite comfortable around people. Last April, we visited friends in North Carolina. Near the development’s community center they showed us where a Killdeer was nesting on a strip of lawn between the roadway and parking lot. Residents had placed a rope barrier around the nest to protect it. The Killdeer was quite comfortable with passing walkers who stopped to look at its nursery. When I approached the nest, the parent spread its tail in minor distress, and I backed off. But later, when it went for a short walk, I was able to approach slowly and see that three of the four eggs had recently hatched; one chick was still wet after breaking from the shell.

The reports of returning migrants are beginning to pile up. Each day another bird is added to the list, and the promise of Spring grows more certain: red-wings and grackles, robins and Song Sparrows, bluebirds and phoebes - and all kinds of ducks. Then there are the residents showing signs of Spring as they begin courtship and look for nesting sites. The crows are noisy; so are the ravens. Starling flocks are dispersing. The single Downy Woodpeckers which came to the suet through the winter are now coming in a pair. Mourning Doves are cooing to one another. Winter calls are giving way to songs. Chickadees sing “peee ... weee.” The “peter, peter, peter” of the titmice greets the first light. From a pine tree Prince Cardinal whistles his song, and from atop a bare cherry tree a Carolina Wren warbles his virtues.

And then there is the “kill-dee, kill-dee, kill-dee”- or perhaps - “dee dee dee dee-ee kildee dee-ee” - those are good sounds. One of the songs of Spring!

Thursday, March 13, 2008

Boreal Chickadee - Newfane/Wardsboro

A Boreal Chickadee has been visiting bird feeders at a home on the Newfane/Wardsboro town line regularly this winter. It comes with a flock of Black-capped Chickadees, usually several times a day. I was able to visit the home owners this morning. After waiting about ten minutes, the Boreal Chickadee made several visits to the suet feeder and a couple of quick trips to the seed feeder.

Boreal Chickadee is resident in Vermont's Northeast Kingdom and at higher elevations in the White Mountains. It is rarely reported as far south as Windham County. The last report that I know of was during Christmas Count week (3rd week in December) in 2000 when a Boreal Chickadee made a very brief visit to a feeder in Brattleboro.

Feeder birds have been erratic this winter. Some people report many birds, other few birds. Located in pine/spruce woods, the feeders at this home were active with Red- & White-breasted Nuthatches, Downy and Hairy Woodpeckers, and a Blue Jay - plus the Boreal Chickadee.



Monday, March 10, 2008

J.J.Audubon - The Kildeer Plover

Reader, suppose yourself wandering over some extensive prairie, far beyond the western shores of the Mississippi. While your wearied limbs and drooping spirits remind you of the necessity of repose and food, you see the moon's silvery rays glitter on the dews that have already clothed the tall grass around you. Your footsteps, be they ever so light, strike the ear of the watchful Kildeer, who, with a velocity scarcely surpassed by that of any other bird, comes up, and is now passing and repassing swiftly around you. His clear notes indicate his alarm, and seem to demand why you are there. To see him is now impossible, for a cloud has shrouded the moon; but on your left and right, before and behind, his continued vociferations intimate how glad he would be to see you depart from his beloved hunting-grounds. Nay, be not surprised if he should follow you until his eyes, meeting the glaring light of a woodsman traveller, he will wheel off and bid you adieu.
from John James Audubon, The Birds of America, 1840-1844

Saturday, March 08, 2008

The Robin Is Not a Sign of Spring

"I saw a bunch of robins in the middle of January’s snowstorm. It sure didn’t look like Spring to me!"

"I saw a robin last week. Spring must be coming!"

Old newspapers in small towns used to report the first robin seen in the year. The person who saw the robin was a momentary celebrity. Spring was coming!

Robins are a sign of Spring! Right?

Wrong!!

Robins are not a sign of Spring any more than Punxsutawney Phil, that pampered Pennsylvania groundhog, is a predictor of weather. Here’s the scoop on Phil: if he sees his shadow, it means six more weeks of winter. If he doesn’t see his shadow, it means an early spring. Or maybe it’s the other way around. It hardly matters. As any sensible Vermonter knows, an early spring and six more weeks of winter are the same thing! It’s one of those pieces of folklore that’s just plain wrong.

So why do we cling to the old wives tale that a robin is a sign of spring? Because, as we all know, all robins go south for the winter and return in the early spring. Unfortunately, that is not true.

In part, we are just not paying attention. Maybe during a long winter, we are too housebound, or too bundled against the cold to notice. But if we strap on our snowshoes and wander the garden or roam the woods - or if we just walk to the corner store for a coffee or newspaper - we may hear the rattle of the robin on any day of the year - even a mid-winter day.

The American Robin is a hardy and adaptable bird, comfortable in just about any habitat which North America can provide. Somewhere in his writings, naturalist Pete Dunne tells of reclining on a frozen hillock on the Arctic tundra, sipping a good malt liquor with a friend, and watching robins busy with their business of foraging for their nestlings.

The hardy robin individuals who make the Arctic their breeding ground head south for the winter. But, what is their primary requirement for a wintering stop? Mild temperatures? Sunny days? Gentle ocean breezes? Nope - those may be the requirements for the weakling human snowbirds, but an Arctic robin needs only one thing. Food!

Driving over Black Mountain last week, a flock of robins flew ahead of my car. On either side of the road, fruit hung heavy on the bittersweet, and rose thrips shown red against the snowpack on the hillsides. Other bushes and trees whose names are unknown to me were also full of berries. Robins are omnivorous. They may prefer earthworms pulled from your lawn during spring and summer, or grubs, or beetles, or whatever else is rich in protein. But when the meat goes into the freezer, they happily become vegetarians, albeit sometimes alcoholic vegetarians, since much of the fruit they consume has fermented on the branches.

Of course, the real bar-stool denizens of the bird world are the Cedar Waxwings. They’re famous for their binges, getting falling down drunk on fermented berries. Literally. They will consume so much alcohol laced fruit, that they fall off the branch and stagger about the ground.

But - the robins. Even those winters when they are not reported, some are probably around, hidden in the forests where there is protection from the elements, venturing out only when the days are milder or ground opens up to provide access to some protein. Conveniently, we are sometimes able to see them even through the frosted windows of our warm dens. But they are not telling us that it is spring. Nor is it the case that "they’re not supposed to be here this time of year." I’d prefer to think that robins are some sort of messenger telling us to get up, get out, get going - enjoy what the world has to offer, even if it is cold outside.

True, most robins do migrate south; I’m certain our local nesters do so. And given life in the arctic winter, I am sure that all robins migrate southward, but some stop far short of the South. They seem to know the charm of New England in the winter.

The robins that do migrate to the South in the Fall, return in the Spring. When the ground opens up, large flocks will appear, moving across the soggy lawns and fields in search of food. Those flocks of robins are a sign of Spring, but they are not the folklorish sign that so many think they are.

No, if you are looking for a sure sign of the advent of Spring, there are several that are far more dependable than "the first robin." Look for the wispy columns of wood smoke rising from sugar shacks. Notice when the first village church announces its "Sugar and Snow" supper. Or maybe you noticed earlier this week your crusty and testy neighbors picking their way through the mud ruts on their way to town meeting. Those are sure signs of Spring!

Or perhaps, like the ancients of old, you want an omen from the skies, a bird sent from the gods with the message that "Indeed, Spring is on the way - Persephone returns to bring life and fecundity to the earth."

If that is what you are looking for, then watch for this bird. Its return is regular, dependable, and a predictable sign of Spring. Watch for the Red-winged Blackbird. The first males will return to the river valley during the second week of March. A friend in Guilford sees the first red-winged on March 8, plus or minus a day or two. At town meeting a neighbor hurried up to tell me there were red-wings at his house that morning. With their fresh, bright red epaulets, the male red-wings hurry northward to find and establish a breeding territory. On a broken reed stem, or bare tree branch, they warn off rivals and limber vocal cords for the luring of a mate: "Conk-a-reeeee. Conk-a-reeee."

That is a sure sign that Spring is coming. Other birds will be following along in quick succession as fast, or faster, than the snow melts. Right now it may not look much like Spring is just around the corner. But pay attention. Chickadees and Titmice are beginning to sing, and migrants are returning. After our long winter, I am anxious for bird song, crocus, and good birding.

Saturday, March 01, 2008

Purple Sandpipers - Hardy Winter Shorebirds

Halibut Point on Cape Ann, Massachusetts, is one of many old coastal quarries. A trail leads past the flooded quarry pit to the built up promontory. Projecting into the ocean, it is a good place to see aerial seabirds, alcids, and sea ducks during migration, or in their wintering waters. The best conditions for seeing birds is during or just after a storm with strong winds blowing toward land. Then the birds are pushed toward the shore. Those can be brutal days to be outdoors, and the accompanying weather often renders the drive from Vermont to the coast an exercise best not undertaken. The day I was there, the wind was blowing gently from the land; it had been doing so for several days. Birding in those conditions is more pleasant, but not always very productive. Birds were far distant; only a few eiders, a handful of scoters, a couple of cormorants, and a loon or two, could be seen diving in the high surf of the high tide.

I scanned the rocky coast beneath the promontory. Small birds were milling over the wet rocks, flying up as a wave was about to crash, then returning to scurry about. They were too far distant to see any field marks, but I knew they were Purple Sandpipers. Purple Sandpipers are the only shorebirds which regularly and dependably winter along the New England coast. Occasionally a few other shorebirds will stay for the winter - small groups of Sanderlings or Dunlin, usually seen on sandy shores. Last year I saw a single Red Knot on the rocks where the Purple Sandpipers were so busy. But the high likelihood is that a shorebird on a rocky New England coast in winter will be a Purple Sandpiper.

It was as pleasant a day as you could ask for on a New England coast in the middle of winter. New weather was coming in, so the sunlight was hazy, but the clouds were just beginning to form up. Wind and temperature were such that I could pull off my gloves from time to time without acquiring immediate frostbite. Nothing seriously impeded the seductive attraction which a rocky coastline holds for me.

Long ago as a very young boy, I traveled with family through New England. Most details are lost to memory, but two remain. One was rock hopping back and forth across a mountain stream. The other was scrambling over the rocky coastline at Acadia National Park, especially around the Otter Cliffs. My uncle, then in his late teens and something of a big brother to me, climbed the cliffs. I was not allowed to join him. Rocky mountain streams and rocky New England coasts have been siren songs to me ever since.

So seeing those distant Purple Sandpipers along the rocky coast around Halibut Point was a double invitation to wander down the trail and go scrambling over the rocks. Except, that the passing years have eroded some of my agility, so I do less scrambling and more careful stepping and cautious climbing.

My already slow pace slowed even more as I came closer to the Purple Sandpipers. I did not want to startle them into flight; it is so easy for skittish shorebirds to burst to the wing on just a whim. Slowly I moved to within a few yards, then leaned against a rock and watched them. Off and on during the next twenty minutes, I took one or two steps closer. Mostly I just watched the show.

Most sandpipers nest in the Arctic and travel thousands of miles to South America. By some evolutionary quirk, the Purple Sandpiper travels only a few hundred miles. It nests in the Arctic, but not as far north as some shorebirds, and winters along rocky coastlines from southern Greenland and New Brunswick to New York. Twenty years ago, I use to see Purple Sandpipers along the exposed jetties in Cape May, New Jersey, but beach restoration has nearly submerged the jetties and removed winter habitat for these birds.

The Purple Sandpiper has been known variously as Rock-bird, Winter Rock-bird, Rock Plover, Rock Snipe, Winter Snipe, and Winter Peep. Those names should tell you that the Purple Sandpiper will be seen feeding among seaweed on rocks in the winter. All of those names are probably better than “Purple Sandpiper.” It is generally a darker bird, but I have yet to develop enough color astigmatism to imagine this dark brown-gray bird as purple. Perhaps the mavens of names are trying to avoid confusion; a close relative to the Purple Sandpiper of the North Atlantic coasts is the Rock Sandpiper of the Northern Pacific. Our Purple Sandpiper breeds across the North Atlantic, including Iceland and Scandinavia, and winters on rocky coasts on both sides of the Atlantic.

Aside from being the only sandpiper likely to be seen on a rocky New England coast in the winter, the Purple Sandpiper is characterized by its stocky build. Its short-legs are yellow; its long beak is orange at its base, becoming dark at the tip, with a tiny nob at the end. But you have to get close to see these characteristics.

More likely, you will see the Purple Sandpiper feeding on wet rocks. Its food is found on these wet rocks below the high-water level. Here is Forbush’s description from his 1925 Birds of Massachusetts: “As the tide begins to drop the birds move around restlessly, often flying from one small island to another, and as soon as the band of gray-white barnacles is exposed, feeding commences. A little later the festoons of rockweed will also be exposed with their wealth of tiny marine creatures upon which the Purple Sandpiper feeds. They seem to prefer the eastern or seaward side of the ledges except in the stormiest weather, probably because the recurring surges of the sea continually turn over the heavy fronds of seaweed, exposing fresh surfaces to the eager little birds searching for snails and other mollusks, and for minute crustaceans.”

This is what I watched on the rocks at Halibut Point. The birds fluttered into the air when a wave was about to break, then returned to scurry over the damp rock, foraging for food. It was almost as though they enjoyed the sport of dancing before the waves. The surf was high on this day, the waves crashed over the rocks, but the water only just ebbed before the birds returned to the hunt. Like sportsmen and athletes, some would call a time-out, retreat to drier rocks, sometimes to refresh themselves with a quick bath in a small puddle before reentering the game.

An aside: I can understand the Purple Sandpipers cavorting before the cold surf; they have adapted to this over many generations. I cannot understand the wet-suit clad surfers I also saw around Cape Ann on this same day trying to find a good wave to ride. These (all of them) young men seem to be ignoring any evolutionary good sense their species has developed.

With the imprint of a young boy’s memory, and the lure of a common, but sometimes elusive wintering Purple Sandpiper, I went scrambling about a rocky coastline on a relatively nice winter day. What more can one ask for? An exercise in nostalgia and good birding!

Saturday, February 23, 2008

Why Are There No Birds at the Feeder?

I’ve had many people ask me, “Why are there so few birds at my feeder this winter?” The short answer is, “I don’t know.”

I don’t have many birds at my feeders either. Through the Fall and early Winter, my feeders were teeming with birds. There were large flocks of finches and sparrows. Common Redpolls were a highlight of the early winter, with a flock of fifty or more feeding throughout the day. Now they are gone. What’s happened?

Before I continue, let me remind readers that I am a birding hobbyist. I am not a scientist. Early in my academic career, I was a major in science and acquired an understanding of how science does its research, weighs its evidence, tests its theory, and arrives at the “facts” based on the best evidence available at the moment. At its best, science relies on empirical data and the research of one scientist can be verified by another scientist. Conclusions are based upon research, not political positions, economic theory, or theological bias - such as those which try to influence a lot of science in our current society.

I may have begun with the study of science, but I swerved into history, and we all know how historians can interpret and reinterpret historical events. There is nothing precise about the writing of history.

Nevertheless, I do try to get the science right as I write about birds. So a disclaimer: I do not know any science about why there are so few birds coming to my bird feeders during the last couple of months. Nor do I know why there are so few birds coming to some other people’s bird feeders.

I also don’t know if the lack of birds at my bird feeders is typical. There are a lot of anecdotal reports to suggest that the reality is complex.

For example: Common Redpolls. I was enthralled with the flock that came to my feeders in the early winter. Then they disappeared. Since the beginning of the year, a single redpoll has come to the feeders a couple of times, spending a day or two, and then disappearing. But a friend atop Newfane Hill announced that a flock of two hundred redpolls were busy around her homestead. And a conversation about bird feeders with a Dummerston resident included many redpolls.

On the last day of the old year, I wrote about the cardinals which came daily to my feeders - Prince Cardinal with his harem of four. Soon after, they disappeared. Occasionally I would see a single male at dusk, or a single female at some other time of the day. But the tiny group was gone. Had the repeated winter storms done them in? Or had they moved southward, trying to avoid the brunt of winter? Unanswered and unanswerable questions?

Last Sunday, cardinals were back at the feeders - Prince Cardinal and at least three females. The same ones as earlier in the winter? Probably, since cardinals are not known to migrate. If so, where have they been? There is always plenty of seed at my feeders, and we clear the snow and ice at least once a day. Had they gone to someone else’s feeders? Had they found another source of high energy food in a place more protected from the elements? I don’t know.

A similar thing happened with other wintering birds. For several weeks, I had only one or two stray chickadees and a single Downy Woodpecker; their feeder visits were brief and erratic. Then the “normal” neighborhood flock returned - several chickadees and titmice, a couple of nuthatches, a pair of Downy Woodpeckers, and a Hairy Woodpecker. In winter, these year round residents forage in mixed flocks and can be nomadic. Apparently, their nomadism has brought them back to my yard.

As many people who have queried me about the absence of birds at their feeders, just as many are unaware of any problem. They have plenty of birds at their feeders - or at least a respectable number. Sighting reports from southeastern Vermont and around the state continue to report wintering northern birds, often in substantial numbers (Pine Grosbeaks, Snow Buntings, Horned Larks, redpolls). Last week I saw a large flock of Evening Grosbeaks in Guilford getting grit and salt from the road, along with doves, robins, and juncos - none of which have been in my neighborhood for weeks.

In spite of the continuing grip of winter, some birds are already on the move. Reports of Rusty Blackbirds have come from a several places. And last Sunday, a caller reported four male Red-winged Blackbirds at her home on Upper Dummerston Road. The red-wings usually begin appearing during the first week of March.

Two weeks ago, I drove to Philadelphia. I left my home with snow squalls swirling. At the Massachusetts border, the squalls were so heavy that it was almost white-out conditions and I considered turning around. By the time I reached Holyoke, the road was dry, the sun was shining, and there wasn’t a white patch to be seen on the ground anywhere. Which leads me to theorize that many birds which we might expect to see, such as finches and some sparrows, have moved southward to where the foraging is a little easier.

It has been a difficult winter. Even people who enjoy winter are getting tired of it. I know several families who enjoy winter sports, but they are not planning on spending the next week’s winter school break skiing or snowshoeing - they’re going to Florida. I’m tempted to make a comment about people who “wimp out,” but the truth is, I wouldn’t mind wimping out with them.

If many birds have moved south, who can blame them. It has been a tough winter, all the more difficult for those creatures which must make their living in this weather. If there are not as many birds at some feeders this winter, it may mean that they have gone south, or it may mean that they have not survived.

Here is a report that has surprised me. Two people have told me about having a Barred Owl at their feeders. In both case, the owl perched on or very close to the feeder. One of them was clearly observed hunting for rodents. Beneath the snow pack there is lots of life and activity. We’ll see the trails and tunnels when it finally melts. I see red squirrels diving into a hole in the snow and reemerging from another hole ten or twenty feet away. The Barred Owls, whose weak talons restrict their prey primarily to small rodents, were coming to where the mice and voles could be easily found. The owls can hear the mice active beneath the snow pack, but how do they break through the ice crust on top? One observer watched the owl as it tried to plunge through the ice crust, and even tried to scratch and break the surface.

Curiously, neither of these owls was harassed by the small birds. They were ignored. Even the Blue Jays payed no mind to the owl.

Are the numbers of birds more or less than usual this winter? I don’t know. Perhaps data from the Great Backyard Bird Count will tell us. What can be said is that winter is a time of harsh gleaning. In nature, there is no sentiment, or sentimentality, for the weak. The strong and the fit survive.

Saturday, February 16, 2008

Mute Swan - Beautiful, Graceful ... and Invasive

An apology ... sort of. Every so often someone will excitedly call me or e-mail me: “Did you see the swans!?” I can seldom respond with any enthusiasm. Because - the swans that are being reported are usually Mute Swans, and unfortunately the presence of Mute Swans is not good news.

Mute Swans are elegant birds - luxuriant pure white plumage, long sinuous necks, graceful swimmers. But they are not native to North America, and like other introduced birds, they pose a threat to native species.

World-wide, there are seven members of Genus Cygnus (from the Latin for swan, coming from the Greek kyknos, also meaning swan), although typical of taxonomic classifications, there is debate whether some subspecies should be accorded their own species status.

Two swans are native to North America. The Trumpeter Swan, the largest native waterfowl in North America, has been returned from the brink of extinction and is being reintroduced in many parts of its former breeding range in Minnesota, Wisconsin, Michigan, and Ontario. There are no recent records of the Trumpeter Swan in Vermont.

The Tundra Swan is our smallest swan, short-necked and gooselike. It nests on the Arctic tundra and migrates to wintering grounds. Many winter along the mid-Atlantic coast. A few may be seen in Vermont during Spring or Fall migration. Most recently, in November 2003 and 2004 Tundra Swans stopped briefly in the Retreat Meadows. The bill of the Tundra Swan is black.

The adult Mute Swan is most readily identified by its unique orange bill and the black mask with forehead knob.

In the last few years, the Mute Swan has become the swan most likely to be seen in southeastern Vermont. Last year a pair nested in the vicinity of the Hinsdale setbacks. To my knowledge, this was the first successful nesting in our area. Murin and Pfeiffer in Birdwatching in Vermont, report that the Mute Swan has “nested in Vermont but the Vermont Fish and Wildlife Department probably won’t allow a repeat performance.”

So, what’s the problem? First, some background. The Mute Swan is native to Europe and western Asia. Its nature and character (elegant, aggressive, silent) made it the subject of many myths and legends. Occasionally it was domesticated for food. More often it was kept as an ornament in the gardens of the nobility beginning at least as early as classical times. The Mute Swan is the national bird of the Kingdom of Denmark, while in Britain, the Crown retains the right to ownership of all unmarked mute swans in open water. Magnanimously, the Queen only exercises her ownership on certain stretches of the Thames and its surrounding tributaries. Swans continue to be a feature in the public parks of Europe.

In the 1800s, many growing American cities expressed their civic pride through the creation of public gardens, complete with paths and ponds. The ponds were decorated with Mute Swans brought from Europe, their wings clipped to keep them in the parks. The pampered swans enjoyed an easy life, settled down and raised families. Naturally long lived (nineteen years is the record for a banded wild swan - thirty to forty years is not uncommon for captive swans) swans often outlived the ponds and estates which kept them. They, or their offspring, went wild. With a high reproductive rate, a lack of natural predators, and an abundance of suitable wetland habitat, these feral Mute Swans have established significant populations, especially along the Atlantic Coast.

A survey conducted in the summer of 2002 found over 14,000 Mute Swans in the Atlantic Flyway. This number had doubled in just sixteen years. The pair that nested in Hinsdale on the Connecticut River last summer raised five young. About fifty swans are wintering in the Turners Falls area. As recently as ten years ago when I moved to southeastern Vermont, Mute Swans were a rare occurrence.

The growth of the Mute Swan population causes several ecological problems. They have voracious appetites and often are a year-round presence. They are capable of disrupting the natural food chain. “Several studies have documented large reductions in aquatic vegetation, and even the complete disappearance of certain plant species in some locales, because of heavy grazing by mute swans. In some areas of the Chesapeake Bay, efforts to restore native vegetation have been seriously hampered by foraging mute swans. In turn, there is a negative impact on native wildlife and fish species that depend on these plants for food and cover.”

During breeding season, Mute Swans maintain a four to ten acre territory, aggressively driving off any intruders, including native species attempting to nest. They have caused terns and skimmers to abandon their nests and have killed Mallard ducklings and goose goslings. Their aggressiveness is sometimes directed toward other animals and even humans. They can be, at the least, a nuisance to pets and people, and perhaps even a danger.

“Adults are not paired for life, contrary to the stereotype of the ‘pining swan’ who has lost its mate. In fact, some have been observed to have as many as four mates, or even ‘divorce’ one mate in favor of another. However, established pairs are more successful breeders than non-established pairs and mute swans do form monogamous pairs for at least a season.”

Ironically, Mute Swans seem to be the only effective control on Canada Geese nesting in many areas, but any benefit derived from limiting the goose numbers is outweighed by the damage the swans cause to aquatic vegetation. On the other hand, their need for a large territory directly competes with the Common Loon, which also needs a sizeable nesting territory. As the native Trumpeter Swan continues its recovery, it may also find itself competing with the Mute Swan for nesting territory.

In the interest of being as fair to the Mute Swan as possible, there is some evidence that it may have been, and therefore may still be, an occasional vagrant to North America. In 1585, while on a scientific exploration to America for Sir Walter Raleigh, John White painted a watercolor which he titled simply, “The Swann.” In the 1960s the British Museum labeled it as a Trumpeter Swan,” probably because its bill is black. However, scientists at the British Museum “say that lead in the paint used by White has degraded over the four hundred years, turning some colors grey or black. The curved neck, the knob, the lifted rear feathers, the entire countenance are consistent with Mute Swan. Research on the painting continues, as does debate as to whether the Mute Swan might have, or could today, occur naturally in North America.

One person’s good bird is often another person’s invasive pest. Good birding is sometimes a messy affair.

Quotations are from the web site of Pennsylvania Game Commission and from wikipedia.org.

Saturday, February 09, 2008

The Short-eared Owl Show

I attended a Short-eared Owl show. I was told that the show began in the early morning, but I did not join the show until two in the afternoon. I watched it until sunset.

When I pulled into the parking area, four people were staring across the barren salt marsh. Short-eared Owl, they told me. Across the ice and snow and broken grasses of the marsh, I saw a dark anomaly. With binoculars I saw the owl’s flat round facial disk. It was still there when I set up my scope and brought it closer with the long lens. It was eating. Then it took flight. In its beak it carried something limp and gray, probably a vole.

The flight was short and when it landed, it resumed its meal. The final remains of its prey disappeared in a single gulp. Then it flew to a stake and perched. From there it surveyed the lifeless looking marsh. Soon it would hunt again.

I wandered slowly, back and forth, along a mile and a half of the Parker River refuge road on Plum Island. Three Short-eared Owls were active along this short stretch. They provided a textbook study of this particular owl, and of life in a winter salt-marsh.

The winter salt-marsh never ceases to amaze me. It is a stark, forbidding landscape. The ponds are frozen. The tidal channels are rimmed with jagged chunks of ice. The reeds and grasses are battered, broken, flattened. Nothing breaks the wind as it sweeps across the open marsh, and the wind, laden with ocean moisture, penetrates. The heavy dampness chills. The winter salt-marsh is not a welcoming place. Forbidding is an appropriate adjective.

And yet ... there is life that goes on about the business of earning its living. In the tidal channels, Red-breasted and Hooded Mergansers dove. The drakes displayed for the hens. Gulls were in constant movement; often one could be seen dropping a mussel, using the hard ice to crack open the shell. Black ducks and geese grazed among the grasses. Robins went from berry bush to berry bush, feeding on the fermented fruit. A mockingbird, his mimicking song still silenced by winter, eyed me with interest and curiosity.

I could easily understand where these birds were finding their food, although I wondered why they might not find a more temperate place to winter.

But consider the birds of prey. In addition to the three Short-eared Owls, I saw at least six Northern Harriers hunting over the marshes and dunes. Somewhere in the large expanse of the refuge, there were wintering Rough-legged and Red-tailed Hawks and at least one Snowy Owl. I did not see them, but there were almost daily reports of their presence. Small rodents make up most of the winter diet of these predators. These raptors may be adapted and accustomed to frigid conditions, but their survival still requires many calories every day. Each of these predators must hunt successfully several times each day.

The owls I watched were consistently successful. The Short-eared Owl is a bird of open spaces - tundra, marshes, grasslands. It is also the owl most likely to be seen hunting in daylight. Owls rely heavily on sound to find their prey. The circular facial disc of the Short-eared Owl acts like a dish receiver, capturing sound and funneling it to the ears. The ear openings are asymmetrical, allowing the owl to triangulate sound and locate its prey. The “short ears” of the Short-eared Owl are not ears, but small feather tufts which are not usually visible.

During the afternoon I watched the Short-eared Owl show. I saw it perch on the ground, camouflaged among the marsh grasses until suddenly it spread its wings for a short flight, landing on prey. Other times it perched on a stake, quite prominent on its elevated position. Its head turned one way, and the other. Then it was still, focused; it took flight - a short flight - landing on prey hidden beneath the snow and matted grasses.

More commonly the Short-eared Owls hunted in flight, climbing and descending, floating nimbly over the marsh. At times they resembled the Northern Harrier , their wings held in a droopy dihedral, but quicker than the harrier. The harrier is a somewhat owl-like hawk with a facial disk to help it hunt by sound; in flight the harrier long and rangy. By contrast, the Short-eared Owl looks like a blunt battering ram, or as Pete Dunne puts it: “a pale beer keg on wings.”

The owls and the harriers did not share the air space willingly. There were frequent aerial dogfights between the Short-eared Owl and the Northern Harrier. Sometimes it looked to me as though the owl was the aggressor, as though it was protecting its exclusive hunting preserve. Other times the harrier made the first aggressive maneuver.

The owl, flying above the harrier, dove and swirled. The harrier rolled on its back, talons up as though protecting itself. But such aerial maneuvers are quick and the purpose not always apparent. I spoke with a photographer who had been watching and photographing the birds all day. He showed me an image where the harrier had rolled in flight onto its back. Visible also was the vole which the harrier had dislodged from the owl’s talons. He described the harrier following the vole to the ground, grabbing it, and flying off. One predator had stolen from another. It is no wonder that predators are often aggressive toward one another.

Hawks usually sit in the open and consume their prey slowly. Owls, on the other hand, try to avoid thieving competitors by swallowing their prey whole. Their digestive system then compacts the indigestible materials (fur and bones) into a pellet. An owl ejects one or two pellets each day. Beneath an owl’s favorite roosting spot there may be a pile of pellets. These pellets have been used by biologists to study diet and foraging patterns.

Like all predators, the Short-eared Owl will take what is available, and this may include a variety of small birds. But its distinct preference is for small mammals. Generally non-migratory, they nevertheless wander, usually in winter, to where the food sources are. When rodent populations explode, the Short-eared Owls somehow get the message and congregate. They have been credited with preventing significant agricultural losses from rodents.

Short-eared Owls are found on every continent except Australia. They have even found their way to the most remote islands on the planet, the Hawaiian Islands, where “Pueo” was worshiped as a god and guardian spirit. On a couple of occasions, I saw a Short-eared Owl hunting on the grassy slopes near the summit of Haleakala on Maui.

It is a curiosity to me that the diurnal raptors, the day-hunting hawks, eagles, and falcons, are often elusive and difficult to study. I see lots of hawks during the Fall migration on Putney mountain, but most are here-and-gone observations. On the other hand, the nocturnal owls have provided a number of extended and rewarding occasions. One of these was the show put on by three Short-eared Owls. They hunted from the ground, a perch, or in the air. They competed with harriers. They swallowed their prey in a single gulp.

The owls reminded me that the winter marsh may appear cold and lifeless. But it is alive with the struggles for survival - with the rhythm of death and of life. At fading light, I was cold, yet conscious that sometimes harsh conditions are necessary for good birding.

Thursday, January 31, 2008

Winter on Cape Ann

Note: This was a post with Short-eared Owl photos. I've remove the photos from this post so they can be used with column on 2/9. Here are a few other photos from winter birding around Cape Ann.

American Black Ducks and Gadwalls photographed near lighthouse on Eastern Point, Cape Ann.


Harlequin Ducks near Andrews Point.


Great Cormorants were roosting at low tide on rocks off the Granite Pier near Rockport.



Began the day birding Cape Ann. At Halibut Point, a flock of 75 Purple Sandpipers were feeding & bathing in their manner, on the rocks as the high surf broke.




Off the Granite Pier in Rockport,captured this Harlequin Duck just as it dove.

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