Pages

Saturday, November 29, 2008

Black Skimmer - an Oddity among the Aerial Waterbirds

If you can get a close look at a Black Skimmer, you might think it has been mutated by some toxic soup. Its beak looks deformed. The lower mandible is noticeably longer than the upper mandible. Clearly the bird is incapable of picking up food. So how does it eat?

That was a question asked by one of the earliest European observers of the Black Skimmer. In the early 1600s, Samuel de Champlain voyaged to Cape Cod, briefly dropping anchor in what is now Nauset Harbor in Orleans. His “Voyages” describe one of the birds observed:

“We saw also a sea bird with a black beak four inches long and in the form of a lancet; namely, the lower part representing the handle and the upper the blade, which is thin, sharp on both sides, and shorter by a third than the other, which circumstance is a matter of astonishment to many persons, who cannot comprehend how it is possible for the bird to eat with such a beak. It is of the size of a pigeon, the wings being very long in proportion to the body, the tail short, as also the legs, which are red; the feet being small and flat. The plumage on the upper part is gray-brown, and on the under parts pure white. They go always in flocks along the seashore, like the pigeons with us.”

The gray-brown upper part described by Champlain suggests that the flock was dominated by juvenile birds who had perhaps wandered northward from breeding grounds along the mid-Atlantic coast. Old natives of Cape Cod knew the skimmers as “them cutwater or shearwater birds used to be with us summer times.”

By the mid-1800s, however, Audubon reported that the Black Skimmer was known in Massachusetts and Maine “only to such navigators as have observed it in the southern and tropical regions.” Along the southern coasts and Gulf of Mexico Audubon found winter roosts with thousands of Black Skimmers.

On a foul day in late October, I drove Beach Drive in Cape May, New Jersey. The promenade/seawall hid the beach, but I briefly glimpsed long-winged birds circling low against the gray sky as they descended to the sand. I parked, climbed to the promenade and descended to the beach. On the open sand, about seventy-five Black Skimmers were roosting in a tight group, all facing into the bitter ocean gale. Wind-blown sleet needled into my back as I inched closer to the roost. A couple of Laughing Gulls were nervous at my presence, but the skimmers seemed remarkably passive.

Older naturalists always included the “economic benefit” of the species they described. Forbush writing in the 1920s, for example, notes that the skimmer’s plumage was of no value to the millinery market and that its flesh was not valued as food. However, “its eggs were prized on account of their large size. As Skimmers deposit their eggs without concealment on the open sands, the same fate overtook them along the northern coast of the Middle States, where they have been extirpated within recent times.”

Thirty years ago when I began birding, I never saw Black Skimmers in southern New Jersey. I saw one at the Chincoteague NWR in Virginia, but it was years before I saw another. Protection programs have allowed the skimmers to reestablish breeding grounds along the New Jersey coast, and they are now quite common. That bitter day a month ago when I watched them huddle close, occasionally taking short flights, and coming back together, was a delight. Had the weather been more agreeable, I would have spent more time.

On a delightful, warm, sunny day last May, I spent an hour watching Black Skimmers as they went to and fro from their roost in a coastal impoundment to forage in a nearby estuary along the Delaware Bay. Skimmers feed by flying just above the surface of the water. Their long, lower mandible cuts the surface of the water. The beak is open. When the lower mandible touches a fish or crustacean, the prey gets swept up, the upper mandible snaps shut, and the bird eats.

Apparently Champlain never saw the bird foraging, since he wondered how it could pick up food to eat. With an upper mandible much shorter than the lower, the skimmer can’t pick up food without exceptional contortions. But, it doesn’t need to pick up food , once it has learned how to skim the water’s surface, grabbing food.

Parent skimmers feed their young by regurgitating food. Young skimmers, like the young of many species, are often sloppy eaters. They can pick food from the ground, since the projecting lower mandible does not fully develop until they can fly.

There are only three species of skimmers in the world; the Black Skimmer is the sole representative in the western hemisphere. Skimmers often forage at night and have keen night vision. Audubon regarded them as almost exclusively night feeders: “They spend the whole night on wing, searching diligently for food. Of this I had ample and satisfactory proof when ascending the St. John river in East Florida, in the United States schooner Spark. The hoarse cries of the Skimmers never ceased more than an hour, so that I could easily know whether they were passing upwards or downward in the dark.”

Skimmers also forage at dawn and dusk when prey is closer to the surface, and during during the day when the tide is low. In the day time their large pupils, adapted for night vision, close to a narrow slit, much like a cat’s eyes, protecting the eye from bright sunlight and glare from the water. They are the only birds with such an eye adaptation.

I finally inched too close to the Black Skimmers for their comfort and they swirled into the air, long wings lifting them easily and gracefully into the gale winds. Buoyant and strong, the flock twisted and turned and wheeled in unison around me, but soon settled again at a slightly more comfortable distance from where I stood.

Birding on that nasty October day was limited to my brief venture onto the beach to see the Black Skimmers. But that was enough to qualify for Good Birding.

Saturday, November 22, 2008

Sanderling - a “True” Sandpiper

I love the seashore and beach most of the year. I am not too keen about the seashore during the summer when the sun is melanoma producing, and the sand is littered with debris that has drifted from inland and is scattered in nearly naked lumps all over the place. But in the fall, winter, and spring that debris has been gathered up and returned to its city scape. Then the seashore beach is in its elemental form. The rising and falling tides stir the sands, smoothing them at the water’s edge, constantly reshaping the sandbars and dunes, and often casting up the ocean’s debris.

In late October, I walked some beaches in Cape May, New Jersey. The low sun of the waning day glared off the placid waves. My long shadow preceded me as I walked slowly along the wet sand, just out of the water’s reach. Another lone walker was far ahead, apparently more intent on exercise than I was; her pace widened the distance between us. I allowed the distance to grow greater as I stopped and watched tiny white shorebirds chasing the waves.

Their legs were a blur as they ran up the sand ahead of the waves. Then they reversed direction to chase the water as it receded - back and forth, like school yard children playing tag - or teasing a playful dog on a leash. The birds I watched were Sanderlings, and they are one of the reasons I love the beach along the seashore.

Sanderlings are common along our seacoasts except from mid-June to mid-July. During that period they are north of the Arctic circle, breeding. They waste little time in that task and are soon back along our coasts, chasing the waves. If you see a sandpiper on a sandy beach going back and forth with the water, barely getting its feet wet, you are seeing a Sanderling.

Audubon knew this bird as the Sanderling Sandpiper. Somewhere along the line, the mavens of nomenclature decided this was redundant, and dropped “sandpiper” from its name. But the Sanderling is arguably the only “true” sandpiper.

The “piper” part of “sandpiper” seems to come from a word meaning “chirp,” or “peep,” hence sandpipers are “birds that chirp on the sand,” or “peep on the sand.” The Sanderling and its closest relatives (in the genus Calidris) are known among bird watchers as “peeps.”

The Sanderling (meaning “little bird of the sand”) is the only sandpiper which you will regularly find on sand - or sandy beaches. I went through the Kaufman guide for the habitats where we are most likely to see other Calidris sandpipers. Here’s what I found:

  • Least Sandpiper - edges of rivers, ponds, marshes
  • Semipalmated Sandpiper - mudflats
  • Western Sandpiper - open flats
  • Pectoral Sandpiper - grassy mudflats, flooded fields (the “grasspiper”)
  • White-rumped Sandpiper - flooded fields, marshy edges of mudflats
  • Baird’s Sandpiper - grassy mudflats, flooded fields
  • Buff-breasted Sandpiper - short-grass plains, plowed fields
  • Dunlin - mudflats
  • Red Knot - tidal flats, sandy beaches
  • Purple Sandpiper - rocky coastlines, jetties
  • Spotted and Solitary Sandpiper (not genus Calidris) - along creeks and ponds

Most of these sandpipers will rest and sleep on sandy flats. On northbound migration, they feed on horseshoe crab eggs buried in the sandy beaches of the Delaware Bay. But their usual, preferred place for foraging, and where they are most often seen by the watchers of shorebirds, is not the sandy beach. Most would be more accurately termed “mudpipers.” But don’t expect any name changes in the near, or even distant, future. There is no requirement for accuracy in a common bird name.

The Sanderling is the exception. The Sanderling is a bird of the sand. It sleeps on sandy flats and forages at water’s edge on sandy beaches. It is a true “bird on the sand that peeps.”

The Sanderling is common, and it is very tempting to see it along a sandy beach - say to oneself, “Sanderling,” and go on to look for something else. But they merit leisurely watching. I stood watching them as the waves broke, spray flying. They were masters of timing - probing the sand, then nimbly running up the slope ahead of the water - then racing the water back down to grab new morsels stirred by the water’s action.

I watched a dozen Sanderlings probing wet sand where the tide had ebbed. Something sent them flying further down the beach. I walked closer to where they had been probing. Tiny little holes dotted the wet sand, an inch apart in random lines. My feet barely left a mark on the hard, wet surface. The tiny feet of the Sanderlings left no mark at all. Had I not been watching, this series of holes in the sand would have posed a mystery, causing me to wonder what could have caused these neat, uniform holes in the sand. But I had seen the Sanderlings.

Most of the year when we encounter Sanderlings, we see them in winter plumage. Then they are white, or gray-white, pale and chunky little birds. In Spring they molts into breeding plumage, briefly sporting a rich, reddish brown on head and foreparts. The times of transition from one plumage to the next present an array of in-between appearances. But whatever the plumage, Sanderlings are most likely to be on the sandy beach chasing the receding waters and speeding from the incoming waves.

On that Cape May beach, the Sanderlings were frenetic in their feeding, but fairly calm with my presence. By slow degrees, I inched closer. I could see them probe with open beak, gulp some tiny delicacy, always mindful of where the water’s edge was, whether to hurry toward the ocean or away from it.

And then suddenly, the flock took flight. In an instant, sixty birds disappeared over the dunes. In the corner of my eye, I saw a dark form. Almost as quickly as I could lift my binoculars, the dark form had also disappeared beyond the dunes. I could only get a feel of pointed wings, but it was enough. Sanderlings were foraging along the shoreline in the late afternoon. So was the Merlin. I had watched Sanderlings ingesting energy against the chilly autumn night. And now I wondered if the Merlin, a falcon of the north, would also be feeding.

I can’t choose between the two, and have no right to do so anyway. So I wished the Sanderlings - and the Merlin - good luck and good feeding.

The seashore birding that late October afternoon was very good.

Saturday, November 15, 2008

More on the Red Bird

“In richness of plumage, elegance of motion, and strength of song, this species surpasses all its kindred in the United States. It is known by the names of Red-bird, Virginia Nightingale, Cardinal-bird, and that at the head of the present article.” So began John James Audubon’s description of what he called the Cardinal Grosbeak, and which we today know by the common name, Northern Cardinal. Early residents or wandering naturalist sometimes tried to associate it with particular states, naming it the Virginia Cardinal and Kentucky Cardinal. It has also been known as the crested redbird, perhaps to distinguish it from the uncrested, Summer Tanager, also red and also southern.

Scientifically, the Northern Cardinal is Cardinalis cardinalis. There are three species in the genus, Cardinalis. Pyrrhuloxia, a bird of the southwest, looks like a gray cardinal with an oversized beak. Vermilion Cardinal is found in northern South America, principally Columbia and Venezuela.

Our Northern Cardinal has been through various scientific classifications and has had a variety of common names as we already know. It achieved its current common name designating it as “northern” in 1983. “Northern Cardinal” was intended to avoid confusion with seven other species which are also called cardinals, even though only one of those species is in the same genus. The only other cardinal which might be seen in North America is the Red-crested Cardinal which escapes regularly in Florida and California.

Most people would be hard pressed to name any of those other cardinals, but to avoid confusion our cardinal is called “northern,” because it is abundant in the South of North America. Confused? What does bother me is the complete lack of imagination and poetry by the academics who decide on names, but that is another column.

“Cardinal” comes from the Latin, cardinalis, meaning “important.” The root meaning was originally “hinge,” and evolved to mean “important” in the sense of something on which an object or idea depended, or hinged. Eventually “Cardinalis” came to designate an important (cardinal) church in Rome and a member of the College of Cardinals which elects the Pope. These high church officials wore (and wear) red robes and red hats. When the European colonists to North America encountered a bird with a red hat (crest) and red robes they called it “Cardinal,” in spite of their generally Protestant and anti-Catholic tendencies.

Bent summarizes the behavior of the cardinal this way: “In the cardinal we have a rare combination of good qualities, brilliant plumage, a rich and pleasing voice, beneficial food habits, and devotion to its mate and family.”

There are many stories about how solicitous the male is toward his mate, how tirelessly he cares for his family, and how strong is the instinct to care for and feed the young. The male has been described as a model husband and father.

There is the story of a pair of cardinals which lost its nest. They rebuilt. While the female incubated, the male began feeding four young robins, being as attentive as the robin parents. When his brood finally hatched, he fed both his own young and the robins’ young.

And then there is the photograph in the National Geographic “Song and Garden Birds of North America” which shows a cardinal feeding goldfish: “Hungry goldfish crowd the edge of a backyard pool in North Carolina as a cardinal passes out tidbits of food. For days the bird followed this strange routine. Alighting on the pool fence, he chirped. As the seven goldfish gathered, he fluttered down and began to feed them. In their eagerness they almost leaped from the water. Food gone, the bird flew off for more. Perhaps this foster parent had lost his own brood.”

But, I suspect that DNA studies will show, if they haven’t already, that cardinals, male and female, are just as free with their favors as are most other species, and that neither are models of marital fidelity. Most broods of most songbird species are genetically diverse. The female has cheated on her mate, and unless there are a lot of free roaming bachelors around, the likelihood is that the male has cheated on his mate as well. I would be surprised if the cardinal were any different.

When we have a bird we really like, we tend to accentuate its “virtues” and over look less desirable traits. This is especially true with the cardinal. The male cardinal is fiercely territorial. He and will attack any potential rival, and, as I just suggested, probably for good reason. He is so paranoid about the presence of another male in his territory that he will attack that male relentlessly. Sometimes the male attacks his own reflection in a window. For several summers we had a resident male who, day in and day out, banged against a bedroom window in a futile attempt to drive away the rival male. Such jealous rage betrays obvious insecurity about the fidelity of his mate. He was so persistent that it is a wonder he didn’t break his own neck, or otherwise do himself damage.

Many people tell me they don’t like Blue Jays because they are bullies and chase away the smaller birds. But watch your resident cardinal. Like most writers, Bent is admiring of the cardinal and only reluctantly reports their truculent side: “Although amiable at times, the cardinal is generally mildly dominant at feeding stations and sometimes decidedly belligerent ....”

I watched my resident cardinal at the feeder this morning. “Belligerent” is a good adjective to describe his interaction with the smaller sparrows on the ground. On one occasion, he even turned a Blue Jay timid.

Looking through my photographs of the cardinal, I do not have any where the cardinal is sharing the bird feeder amiably with other birds. He has sent them away. I have one winter photo with the cardinal on the tray of the bird feeder. It is snowing heavily. The white pines in the background are almost white with accumulated snow. On top of the feeder, looking timidly over the eave are three pigeons. Pigeons are big birds, roughly twice the size and four times the weight of a cardinal. But Mr. Cardinal was in no mood to share his feeder. They had to wait their turn.

I love the cardinal. He is gorgeous (so is she). He is hardy; you have to admire a creature that doesn’t flee south just because of a little snow and cold. He is a survivor.

But what I love most about the cardinal is that he and she sing any time during the year, even on a snowy day in January. You have to love that!

Good birding!

Saturday, November 08, 2008

The Red Bird

Bird calls are very difficult to distinguish. Most are some form of chip, which sounds like every other chip to anyone who does not have an auditory acuity, a great memory, and lots of experience.

However, there is one chip that I recognize almost all the time and wherever I am. It is a chip - or as some render it, tchip - that I hear from my feeders when the sky is just beginning to lighten in the morning. I hear the tchip in the evening as the last light is fading. I hear it on sultry summer evenings, on promising spring mornings, and wintry days when snow quickly deepens or frigid winds howl. I poured my first cup of coffee this morning, cupping the mug to warm my hands after my frosty walk out to the road for the morning paper. Through the thermal paned kitchen window I heard the familiar tchip and could just make out the crested figure hopping over the frosted grass.

First in the morning, last in the evening, frequent through the day when weather is foul or young fledglings need easy foraging, the Northern Cardinal is a bright splash of cheerful red during every season of the year. He is a welcomed presence at every backyard feeder. The cardinal would probably lead a poll which asked people to name their favorite bird. When people report cardinals at the feeders, they do so with underlying satisfaction. When the cardinals are absent there is a sense that a small, but important, pleasure in life is being withheld - as though one’s favorite glass of wine could no longer be sipped.

The male cardinal sports the bright red. The female is a rich golden brown with splashes of red and the characteristic cardinal crest, a beautiful bird in her own right. But it is the male that draws the attention. He stands out against the white snow, when singing on a budding spring branch, when dashing about in summer to feed his young. When you see a cardinal, you know, almost immediately, that it is a cardinal.

The only other bright red bird that we might expect to see in our New England states is the Scarlet Tanager; he is bright red with black wings. But the Scarlet Tanager is a tropical species that is only present during the late spring and summer, and stays pretty much in the mature forest. He is not a backyard feeder bird.

The presence of the Northern Cardinal in Vermont is a rather recent occurrence. John James Audubon reported the “cardinal grosbeak” as “very abundant in all our Southern States ....They are found in the maritime districts of Pennsylvania and New Jersey, where they breed, and where a few remain the whole year; some are also seen in the State of New York, and now and then a straggler proceeds into Massachusetts.”

The Massachusetts ornithologist, Edward Forbush, knew the cardinal as a year-round resident in the vicinity of New York City, but he basically regarded it as an abundant southern species, and his account is rather limited.

The Life History of the cardinal by Alfred Cleveland Bent, published in 1968, begins: “As we travel southward from New England’s ice and snow to meet spring halfway, we are greeted by the loud peto, peto of the tufted titmouse, the lively, striking song of the Carolina wren, and the rich, whistling notes of the cardinal redbird, three birds we rarely see in New England. They seem to be welcoming us to the land of sunshine and flowers, and their music brings a heart-warming change from the bleak and silent woods we have left behind.”

Forty years later, these three southern species to which Bent referred are all present in most of our Vermont neighborhoods throughout the year. We no longer have to travel south during the ice and snow to enjoy the Tufted Titmouse, Carolina Wren (the least common of the three) or the Northern Cardinal. The cardinal is undoubtedly the favorite of the three.

The cardinal has been extending its range into the snowbelt. Toward the west, it can now be found in western Nebraska and Kansas, and sometimes into Montana and southern Alberta. It lives year-round in central Minnesota and Wisconsin, southern Ontario and on into Maine. In 2006 and 2007, the Christmas Bird Count north of Minnesota in Ontario recorded cardinals for the first time.

Audubon found “a great number” of cardinals “as far up on the Ohio as the city of Cincinnati.” For the last several years, the middle of Ohio (well north of Cincinnati) has been, in the words of Birder’s World, the “cardinal capital of the world.” One Christmas Bird Count last year counted a record 3,045 Northern Cardinals in the fifteen mile diameter count circle.

The authors of the Northern Cardinal monograph in Birds of North America cite three reasons for why the cardinal has extended its range and is thriving in northern winters. First, warming climate means less snow depth and easier foraging. It also means that less food is needed to stay warm.

Second, residential encroachment into forests and farmland with its hedgerows have created more cardinal friendly edge habitats. These habitats produce winter food and nest locations.

Finally, well-stocked bird feeders in winter: in the truly foul weather, when the snow pack is deep and the temperatures are low, backyard bird feeders provide easily attained food for generating the body energy needed to stay warm and survive. Many experts credit bird feeders for enabling cardinals to expand their range into the hostile winter climes.

The Northern Cardinal is most abundant in our southern states, but in accord with its common name, it is moving northward. Indeed, it has become an icon of the December holidays and the northern winters: the bright red cardinal on a white, snow covered branch - or resting among the needles of an evergreen tree - or on perched among pine boughs amid holly berries. Forbush put it this way: “when in winter a thick carpet of snow lies on the ground, its plumage seems to shine with unusual brilliancy in the reflected light from the snow and it stands out in marked contrast to the wintry background.”

The cardinal in winter is an assurance of good birding.

Monday, November 03, 2008

Fox Sparrow

I missed the Fox Sparrow in my yard during Spring migration. Reports have been coming from around the state of Fox Sparrows showing up, and I was beginning to worry that they might pass me by. Not so. The Fox Sparrow showed up this morning and has been coming and going all day. Such a big, handsome bird.

I had some trouble getting a decent photograph; I think I accidentally pushed some buttons which altered the automatic settings. I did two things. I corrected the settings. And then I took the radical step of washing the kitchen window - both outside and inside. (The kitchen window serves as cat TV, and the inside was full of nose marks from their intense interest in the programming.)

But there is no substitute for being outside. While waiting for the Fox Sparrow to reappear, I took the photos in the previous posting. The Fox Sparrow did not cooperate, but the Carolina Wren did, coming repeatedly to the sunflower and suet feeders. I hope it takes up residence in the neighborhood.


Birds in the Apple Tree

A focal point in our back yard is the apple tree. The apple tree came down in an ice storm just weeks before we bought our Vermont home almost twelve years ago. It re-sprouted from the roots and has gradually become a favorite stopping place for birds as they check for predators before going to the feeder. Last winter, with a three plus foot snow pack, food was scarce and deer came through the yard regularly - though always at night. They licked the seed from the platform feeder and then scraped the bark on the apple tree. We were sure it had been girdled and would die. Instead, it blossomed and produced an abundant crop of apples, although I think the apples are from the root stock. I suppose they are edible, but not to me. I also suppose they'll provide deer food in the winter, though there is lots of food available all over this year.

But all that is beside the point. The point is that the apples, and the remaining yellow leaves provide a wonderful frame for the perching birds. Late this afternoon, I sat on the backporch watching the birds & photographing them. Here are a few of the birds which paused in the apple tree.

Dark-eyed Junco

American Goldfinch

Common Grackle

Northern Cardinal