Bald Eagle
Haliaeetus leucocephalus

Bald Eagle

In 1782 the bald eagle was made the national symbol of the fledgling United States over the objections of Ben Franklin, who favored the wild turkey. The eagle, according to Franklin, was a "sharper," a robber, and "frequently lousy." It may well be that even by that early date the bald eagle was showing unpleasant symptoms of living in proximity to people, because studies of the big bird done in relatively undisturbed areas of Alaska show that the bald eagle is in fact a bold and versatile predator. In Alaska bald eagles will take prey ranging from sea otter pups and sea-birds to spawning salmon. They also consume carrion, which is an important food source for young birds. Usual food for Eastern eagles is fish and carrion.

The bald eagle provides a fitting symbol for the United States for a number of reasons. One is that balds are truly magnificent birds, standing 3 feet tall and with a wingspan that may reach 7 feet. Weight ranges from 8 pounds for the smaller males to 15 pounds for large females. Adult eagles sport a white head that gleams when the bird is in flight; this is balanced by a white tail. The white areas are offset by a dark brown body. Immature birds lack the identifying white head and tail, and are sometimes mistaken for golden eagles. Immatures are brown with varying amounts of white on the wings and body. Their mottled plumage is shed in a series of yearly molts, until adult resplendence is reached at the age of 5, 6, or 7.

Immature Bald Eagle
Benson, 4 year old immature bald eagle

Another reason the bald eagle is an appropriate national symbol is that the bird has an extensive geographic range in North America, extending from California and Florida up into Alaska and northern Canada. However, the eagle's domain has shrunk drastically in recent years. This is in distinct contrast to the bird's image, which has appeared on everything from the seal of the United States to advertisements for coffee. The real bird was bountied for decades, and today illegal shooting accounts for up to 50% of the species' mortality. Other threats are habitat destruction (most severe in New England and in the Great Lakes region), pesticide contamination, and lead poisoning from ingestion of lead shot. As a result, although downlisted to threatened on the Federal Endangered Species list, most states include our national symbol on their endangered species list. In Alaska, which hosts a thriving population, the bird is considered to be neither endangered nor threatened. Hawaii alone among the 50 states has no resident bald eagle population.

Banning of the pesticide DDT has helped the bald eagle greatly, and while the species still faces difficulties, it is now on the comeback trail. Fans of the bald eagle, who see the bird as a living embodiment of nobility, courage, and national resolve, are cheered by this good news. In this instance, they feel, the usually astute Ben Franklin was very, very wrong.

For the story on our resident bald eagle, used in our education programs, go to Resident Bird Bios.





American Kestrel
Falco sparverius

American Kestrel

 

This brightly colored little bird is the smallest and commonest of the five North American falcons. Also known, confusingly, as the sparrow hawk (the Old World sparrow hawk is a different bird altogether, an accipiter that resembles our native sharp-shinned hawk), the kestrel is found over much of the United States both summer and winter. While some birds migrate southward in cold weather, others remain beind, alone or paired. One of our tiniest birds of prey (some owl species are even smaller) the kestrel measures 9 to 12 inches long, with a wingspan of up to 2 feet. Male and female kestrels are differently colored, a departure from the usual raptor pattern, in which gender difference is indicated by size - females larger, males smaller. Kestrel sexes are similar in size, and both have a rusty-red back and tail with a black and white pattern on the head, including the dark stripe under the eyes worn by almost all falcons. However, the male sports blue-gray wings, while the female, by contrast, is more drably dressed in brown.

In England kestrels are sometimes called windhovers, from their habit of hovering over fields. The same habit can be observed in the American kestrel, which can often be seen suspended in the air over open areas, wings beating so rapidly they blur. Kestrels can also be seen perched on fence posts and utility poles and wires by roadsides, where road shoulders, verges, and even median strips attract mice. The birds are not fussy about habitat, however, and have been encountered in urban settings. Roosting places in buildings are usually in wall niches or in holes under the gables roofs. Nest sites are chosen by the male, and in the East nest selection usually takes place around the first week in April. First choice is a cavity of some type. This may be a natural cavity in a tree, or one made by another bird, such as a flicker. Cavities in cliffs and buildings are also used, as are man-made nesting boxes. Once the male has chosen a likely site, the female looks it over and passes judgment. During this period the pair is very noisy, communicating with the characteristic kestrel klee-klee-klee call. If the site passes inspection, the female lays 4 or 5 eggs, incubating for roughly 30 days. The young fledge in another 30 days.

The kestrel's staple food is mice, although it consumes vast quantities of large insects such as crickets and grasshoppers in the summer. Songbirds may also be taken, particularly in winter; kestrels have been known to snatch unwary victims from bird feeders. The little falcons will also hunt lizards, snakes, frogs, and have been observed preying on bats.

In general small birds have shorter lifespans than the larger species, and the elfin kestrel does not have a long life expectancy. In the wild, average lifespan is a little over one year; in captivity, however, ages of over 10 years have been recorded. While the kestrel may fall prey to accidents as well as to other raptors, its major enemy is man. The majority of banded specimens that are recovered have been shot.

For the story on our resident american kestrel, used in our education programs, go to Resident Bird Bios.





Saw-whet Owl
Aegolius acadicus

Saw-whet illustration
© Saw-whet Owl
notecard available from
DVRC notecard collection.

The Munchkin-like saw-whet seems to have been designed by Walt Disney. This appealing, diminutive owl, 7 inches long and weighing all of 3 and one-half ounces, appears to be all head and great golden eyes. The eyes are set off by a white V-shaped patch that becomes larger and less sharply delineated after the bird's first year. It is difficult to think of this sprite as a predator, but the saw-whet is armed with needle-sharp talons, and mice and songbirds as well as insects fall prey to it. This is the smallest owl found in the East (believe it or not, a few Western species are even tinier), and it can be distinguished from the screech owl, another little species, by its smaller size, rounded head, and lack of ear tufts. The saw-wheat's call has a raspy, metallic quality, and the notes produced occur in groups of three. Another saw-whet call with a metallic quality is a pinq or zinq that sounds very much as if it were made by a grasshopper. It is actually produced by the male saw-whet during the spring courtship period. By imitating these calls at night, you might be lucky enough to lure the elfin owl within viewing range. Otherwise, this is a hard species to see in the wild, even though it is common in this area. The saw-whet prefers dense forest, and usually uses a thicket or clump of trees as a roosting site. Stands of pine or hemlock and rhododendron or honeysuckle bushes are all favored, and the little owl prefers a low perch; it is seldom seen in high branches. This tiny bird, like other owl species, enhances the camouflaging effect of its cryptic coloration by remaining virtually motionless during the day. If you do spot a saw-whet, however, you'll discover that this is a remarkably tame, docile species that will put up with an amazing amount of huma n disruption and camer a-b randishin-; before it decides to seek quieter quarters. The species is most easily seen in late autumn or early winter, a period when several, someti mes scores, of the birds tend to gather in a favorite spo t. While the saw-whet does not mig rate in the manner of other raptors such as the broad-winged hawk, it does move southward during harsh winters.

This is a nocturnal hunter, one that is seldom seen moving about in daylight unless it is driven from its perch by a particularly determined mob of other birds. This behavior, called mobbing, is manifested by many birds, from bold chickadees, nuthatches, and mockingbirds to blue jays and crows, against all birds of prey. The object is not to physically harm the predator, but to warn other birds of potential danger by constantly calling and flying close to the raptor. This continual harassment may also get the unwanted and probably annoyed raptor to move on.

To other birds of prey, particularly to other owls, the tiny saw-whet is an easy meal, so this predator frequently becomes the preyed-upon. It is often a victim of severe winter storms that prevent it from hunting. Another all-too-common fate is a collision with a car as the owl swoops down over a highway to snatch up a mouse.

For more on the resident Saw-whet owl used in our educational programming see Resident Bird Bios.





Barred Owl

Strix varia

Barred Owl

The dark-eyed barred owl has a gentle, soulful expression that is mirrored by the bird's temperament - this is an unaggressive species. The barred is the East's next-largest resident owl, second only to the great horned owl, but there is a vast difference between the two species. The formidable great horned owl, at 3 pounds, is a top predator, capable of taking prey up to the size of skunks or fox, even porcupines if it is hungry enough. Great horned owls are fierce defenders of their young, and are one of the very few birds of prey on record as having killed people. The barred owl, by contrast, is dangerous only to small mammals, frogs, snakes, and fish. This is due partly to its lack of aggression, and partly to the fact that under all those soft feathers there isn't much bird - male barreds average only 13 ounces, females 17. The species' name comes from the crosswise barring on the bird's breast feathers; the pantaloonlike belly feathers are streaked lengthwise. The barred owl is gray-brown overall, quite different from the tawny-brown of the great horned owl. Barreds lack the ear tufts of the great horned owl, and they utterly lack their larger relative's yellow-eyed demonic glare. The soft brown eyes of the barred owl are surrounded by dark concentric rings that give it a bemused look, as if it found this wicked world a bit too much.

The barred owl, like the great horned, is sometimes called "hoot owl." Both species do hoot, but the barred owl is more emphatic in its vocalizations, and its voice has a higher pitch. Its best-known call is a series of 8 accented hoots, in groups of 4: hoohoo-hoohoo, hoohoo-hoohooaw. That descending note at the end is characteristic of the barred owl. This talkative species can also bay like a hound, scream, shriek, and whistle. To the superstitious the barred owl must sound like one of the unrestful dead abroad on some sinister mission, and surely some ghost stories trace their origins to the unearthly noises made by this bird.

Baby Barred Owls
Baby Barred Owls

Their uncannily silent flight may also be responsible for stories of restless spirits. Like other owls, barred owls have velvety-soft feathers. This softness, combined with a fringed leading edge on the flight feathers, dampens sound, and enables the owl to fly virtually noiselessly. Another aid to silent flight is the fact that the barred owl's wingspan averages 43 inches - a big wingspread for such a light bird. Broad wingspan plus low weight equals buoyant flight, and the barred can move through the air like a moth. Prey is captured partially by being seen, and partially by being heard. Hearing is extraordinarily acute, as is eyesight - even in daylight.

The gentle barred owl sometimes falls victim to the great horned owl - there is no sense of family among the various owl species. Many barreds meet their death on highways when they swoop down after a mouse, only to collide with a car instead. And, sadly, they are sometimes shot, since they are inquisitive birds that will follow people to see what they're up to.

For the story on our resident barred owl, used in our educational programs, go to Resident Bird Bios.





Eastern Screech Owl
Otus asio

Screech Owl

The soda-can-sized screech owl is the smallest owl with ear-tufts found in the Northeast. The species averages just 7 ounces in weight, 8˝ inches in length. As is the case with almost all owls, female screech owls are larger than the males. Despite its diminutive size, this is an audacious owl, one that will attack birds and mammals much larger than itself if it is hungry enough. Screech owls have been known to kill prey the size of ruffed grouse, and domestic chickens and ducks. Typical prey, however, would consist of small rodents such as mice and voles. Vast numbers of insects are taken in the summer, and the diet is rounded out with small birds reptiles, amphibians, and even fish.

The yellow-eyed screech owl comes in two color phases, gray and rusty-red. This color difference is unrelated to age, sex, or season. It may be related to geographic distribution - gray birds tend to live in areas of evergreen forest, while red birds tend to be found in areas of deciduous forest. Both colors are marked with a complicated and camouflaging barklike pattern that renders a perched bird almost invisible. Aids in camouflage are the owl’s ear-tufts, which can be erected and lowered at will. When a screech owl goes on the alert, it raises the ear-tufts, pulls its feathers in tightly and narrows its eyes to slits. The result is an uncannily accurate imitation of a tree branch, an imitation the owl enhances by remaining motionless until the danger has passed.

The screech owl is a year-round resident throughout most of its range. In the Northeast, typical habitat is a wooded area that includes open fields and a water source. In years gone by the owl frequently nested in orchards, living well on the abundant rodent, bird, and insect life found there. Today, however, fruit growers’ heavy reliance on pesticides means that orchards are no longer fruitful places for screech owl. The species will live close to human habitation, and will accept man-made nesting boxes of the-type designed for the American kestrel or the wood duck. Eggs usually number 4 or 5, although more may be laid if food is plentiful. Incubation lasts approximately 26 days. Screech owls will vigorously defend their young, and will even attack people who venture too close to the nest.

When young screech owls are in their 4th or 5th week, they leave the nest, even though they are still too young to fly. Their clambering about on tree branches seems to be a kind of warm-up exercise for flight. At this stage many young birds end up on the ground, and there they are sometimes found by people who assume that they are orphaned and in need of human care. In fact the parent owls are still feeding the young birds, and the babies should be left where they are or placed on a branch nearby. Reared by, hand, they will irreversibly imprint to people and have to remain in captivity.

The attractive little screech owl has been saddled with an unfortunate name. The species’ typical cry is not a screech at all but a haunting, quavering trill, quite melodic in nature. The call has an eerie, ventriloquial quality that makes pinpointing its source very difficult.

For more information on our resident foster screech owls, go to Resident Bird Bios.