Current Status: In Pennsylvania, the long-eared owl is listed as threatened and protected under the Game and Wildlife Code. It is a "High Level Concern" species in the State Wildlife Action Plan. All migra-tory birds are protected under the Migratory Bird Treaty Act of 1918. The long-eared owl has a distribu-tion that stretches around the globe, including the forested habitats of Europe, Asia, and Africa, as well as North America. It is near its southern range limit in Pennsylvania, but occasionally occurs further south in the Appalachian Mountains and in migration.
Population Trend: The long-eared owl often is considered an enigma by birders and ornithologists. It is shy, quiet, and secretive. This makes its population trends difficult to understand, but the species appears to be declining and is listed as endangered, threatened or of special concern in other states. In Pennsylvania and nearby states, ornithologists' comments from the 1940s indicate that this species was more common then. Its decline may have begun several decades ago. Even after two Pennsylvania Breeding Bird Atlas projects, the long-eared owl remains one of the state's most rarely encountered nesting species. It was one of the least-reported birds during Atlas surveys in 1983-1989 and 2004-2009. Volunteers found evidence of breeding in only 18 blocks during the first Atlas. During the second Atlas, it was discovered in only 14 of the nearly 5,000 survey blocks, with confirmed breeding in only 4 blocks. Christmas bird count data also suggest declines in wintering populations. The long-eared owl was "status undetermined" for many years in Pennsylvania, but was listed as a state threatened species in 2012. In recent years, volunteer monitoring of suitable habitat resulted in documentation and protection of several winter roosts in the Bucks, Lebanon and Adams counties.
Identifying Characteristics: The long-eared owl is a medium-sized owl (about 15 inches long) with narrow ear tufts and bright yellow-orange eyes (actually the iris) set in a russet facial disk edged in black. Although superficially similar to the great horned owl, the long-eared owl is about one-fifth of its bulk and with more closely spaced ear tufts (that point up not out), a relatively longer tail, and no white throat patch. Conversely, the long-eared owl is larger than the much more common eastern screech-owl, which is only 8.5 inches long and much stockier in appearance. The two sexes are indistinguishable by plumage but females are slightly larger.
The front of the long-eared owl has a distinctive herring bone pattern. Long-eared owls are typically shy and well-hidden, notorious for blending well with their roosting tree. They often perch adjacent to the tree trunk and "freeze" stiff in a slim, cryptic pose to avoid detection. The long-eared owl has a long wingspan - about three feet - for its size so it is very buoyant and efficient flier and it looks larger than it really is. In flight, it can be confused with the closely related short-eared owl because the long-eared owl flies with its tufts tucked back against the top of its head. Both of the "eared owls" have a dark "wrist patch" but the short-eared owl's patch is more prominent. At the end of the yellowish-buff wing patch on the primaries, the long-eared owl has four to five narrow black bands while the short-ear has two to three darker bands that are bolder and end in a dark tip. The tail of the short-eared owl is more boldly barred than the long-ear and it has a pale trailing edge of the wing. The long-eared owl also has streaks continuing down its belly while the short-eared owl's streaks are confined to the chest. Overall, the long-eared owl is much darker than the short-eared owl. Vocalizations are important for owl identification. This species is normally quiet, but the male long-eared owl's advertising call is a deep or "whoop." The female gives a nasal or a higher toned somewhat like the sound of a toy trumpet, a bleating lamb, or the sound made by blowing through a paper and a comb. Males display with an irregular flight" around the nest grove that includes deep wing beats, glides, and occasional wing claps. Long-eared owls also have a variety of other vocalizations including various moans and squeals best heard at close distance but helpful for surveying and monitoring. The calls made by juveniles have been described as sounding like "a squeaky gate" or "rusty hinge."
Biology-Natural History: The long-eared owl is a consummate rodent-hunter of open county. Small rodents are the primary food item of long-eared owls that actively hunt them by quartering over open fields and forests and along edges. Long-eared owls typically fly low and steadily over the ground searching very methodically for prey, probably mostly by ear. Although some researchers have considered it a prey specialist, more recent studies suggest that it is an opportunist that takes advantage of whatever small rodents and other prey are available. Voles, deer mice, and shrews are among its favorite prey. Its diet can be varied and include small birds, reptiles, and earthworms. It will hunt and flush flocks of roosting small birds, particularly house sparrows (Passer domesticus). Sometimes it will sit and wait in the open on a fence post, stump, or tree for prey to appear or make detectable sounds.
Owls tend to be nighttime birds, but the long-eared owl is more strictly nocturnal than other owls, almost always foraging in the dark between dusk and midnight. This is a "surprise hunter" that sneaks up on its alert prey. As other members of the owl family, it is well-equipped for night-time hunting. The long-eared owl can be a silent hunter, because the leading edge of its wing has comb-like fringes and the dorsal side of its flight feathers have downy sur-faces that dampen the sound of its wings. The ear openings of this owl are large and asymmetrical which allow it to detect prey by sound in complete darkness. The long-eared owl has an elongated profile with relatively long wings and low wing-loading so it is very efficient at flying over the open country.
Long-eared owls nest fairly early in the year, sometimes they start nesting in March, but usually by mid-April. They generally take over an abandoned stick nest of a crow, heron, hawk, or squirrel or use a tree cavity. Some pairs apparently nest in the same woodlot where they roosted in winter. Although males perform flight displays over good nesting habitat, the female apparently chooses the nest site shortly before laying. Pairs apparently bond over winter, probably in conjunction with a communal roost. Females sit very tightly on the nest and the male usually perches nearby. Females lay 2-10 eggs, normally 4–6, that are pure white and oval in shape. These are incubated only by the female for 26-28 days. The nestlings are brooded for about two weeks and leave the nest for nearby branches at about three weeks. Some long-eared owls begin nesting when many northern migrants are still on their wintering ground. So, it can be difficult to differentiate between the migrants and breeders. Nesting is often complete before June, but some are still tending young in nest in July. It is very easy for nesting birds to be overlooked, even where there is a very active birding community.
Unlike some of our other familiar owls that are permanent residents (great horned, barred, and eastern screech-owls), the long-eared owl is migratory. Winter sightings are fairly rare, but tend to be in the Piedmont, the Lake Erie shore, or farm country where there are pine stands. Long-eared owls may congregate in communal roosts of several birds, sometimes as many as 50. The size and repeated use of these roosts suggest return of individuals to the same areas. These roosts should not be disturbed because they are important for the survival of the owls during a stressful time of year. In North America, the record life-span is nine years, but one has lived to 27 years and nine months in Europe.
Habitat: Long-eared Owls roost in dense vegetation and forage in open grasslands or shrublands; also open coniferous or deciduous woodlands. They occur at elevations ranging from near sea level to above 6,500 feet. In Idaho, large numbers of Long-eared Owls nest in willows, cottonwoods, and junipers adjacent to shrubsteppe; in several western states these owls also often build their nests in brushy vegetation adjacent to open habitats. In some areas, including in Michigan and western Oregon, Long-eared owl nests are found in coniferous or deciduous forests near open meadows.
Food: Long-eared Owls eat mostly small mammals, including voles, many kinds of mice, kangaroo rats, shrews, pocket gophers, and young rats or rabbits. They hunt over open ground or below the canopy in sparsely forested areas. Prey items usually weigh up to about 3.5 ounces, often less than 2 ounces. They also sometimes eat small birds, capturing them on the ground or (in the case of roosting birds) from low vegetation. Rarely, Long-eared Owls eat moles, bats, weasels, chipmunks, ground and tree squirrels, snakes, and lizards.
Behavior: Long-eared Owls hunt on the wing, coursing back and forth low above open ground. They may also hover over prey, or hunt from perches in strong winds. They kill small mammals with a bite to the back of the skull, and often swallow their prey whole. Nesting Long-eared Owls sometimes form loose colonies, occupying nests as close as 50 feet apart. They may also share nesting areas with American Crows and Black-billed Magpies. Outside of breeding season, the owls roost in groups of up to 100 birds. Older nestlings are called “branchers” because they leave the nest to take up residence in surrounding trees. They move around by jumping, hopping, and pulling themselves up with wings and bill. Long-eared owls usually form monogamous pairs. Bonding probably begins in winter, before communal roosts disband. Courting males make a complex series of calls and perform an aerial, zigzagging display over suitable nesting habitat, with glides and winbgeats interspersed with wing-claps.
Backyard Tips: Long-eared Owls may nest in artificial baskets and open-fronted nest boxes.
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