Hermit Thrush (Catharus Guttatus)

Distribution

Breeding: From Alaska, central Yukon, north-central Saskatchewan, Manitoba, Ontario, south-central Quebec and Labrador, Newfoundland, and Nova Scotia; south to the mountains of southern California, Arizona, southern New Mexico, and extreme western Texas. The upper Midwest, north-central and northeastern Minnesota, central Wisconsin, north-central Michigan and in the East to the mountains of West Virginia and Maryland, and along the Atlantic coastal plain to Long Island and central New Jersey.

Winter: Southern United States, northeast to southern New England and south to Guatemala and El Salvador.

Breeding habitat

Inhabits a variety of coniferous and mixed conifer-hardwood forests up to approximately 4,000 feet (1,220 meters) in the northern Appalachians and up to the tree line in the Western Mountains. Surveys in Michigan found a preference for dry coniferous forests such as jack-pine plains and conifer plantations, as well as mesic mixed forest types dominated by northern hardwoods and spruce. Also favor edges such as the margins of lakes, clearings, burns, and second-growth areas rather than the interior of mature stands of trees. There is some overlap with Veeries and Swainson’s Thrushes, but Veeries generally prefer wetter, more deciduous woodlands, and Swainson’s Thrushes tend to breed more within the forest interior.

Conservation status

Among the forest thrushes, the Hermit Thrush is the one species that shows stable or even increasing population trends throughout its large range. It is seemingly tolerant of various disturbances, but in many areas it is a species associated with large and mature forests. Why this species is successful while other closely related thrushes are declining is one of the mysteries we are trying to understand through the BFL study.

Description

Male: The upperparts vary according to region, from olive-brown to gray-brown. The reddish tail is the most distinguishing feature of the Hermit Thrush. Conspicuous white eye-ring and a spotted buffy or whitish breast. The eastern forms have buff-brown flanks, the western mountain forms are larger and paler, and the Pacific Coast forms are smaller with grayish flanks.

Female: Same as male.

Juvenile: Feathers on the back, tail, and head have buffy edges; breast and flanks faintly barred.

Vocalizations

Song: A beautiful flute-like song made up of a series of varied phrases, separated by long pauses. Each of its phrases begins with a long, clear introductory note, followed by a variable series of shorter notes. The phrases vary considerably in pitch and seem to drift or trail off at the end of each phrase. Clearer and often higher pitched than the Wood Thrush’s song.

Calls: Two common call notes: a soft chuck or chup and a harsh, rising wee-er, similar to the call of a catbird. Given as an alarm or when the bird is agitated.

Foraging strategy

Forages mostly on the ground by hopping and then stopping abruptly to scan for prey. Turns fallen leaves over with bill to search for food. Also gleans from foliage and branches in the understory and in young saplings, occasionally much higher up in the trees. Sometimes takes insects or berries from vegetation above the ground while hovering.

Diet

Eats mostly beetles, ants, caterpillars, grasshoppers, crickets, spiders, sow bugs, snails, earthworms, and sometimes salamanders. In the fall and winter eats more fruit: pokeberries, serviceberries, grapes, elderberries, mistletoe berries, and raspberries.

Behavior and displays

• Often sings from a high, exposed perch. Begins singing in the pre-dawn and sings past dusk.

• Incessantly flicks wings, a behavior that distinguishes this species from other forest thrushes.

• “Wing flash”: stands erect and orients wing or wings toward another bird. Flashes the wing quickly, displaying a buffy wing-stripe, and then flees.

• Raises and lowers its tail after alighting or when alarmed.

• When performing an agonistic display (a behavior used to threaten another bird), the bird holds its body in a sleek, erect posture with the bill pointing upwards, raised crest, and flicking wings.

• Has been observed “anting.” Anting occurs when a bird picks up a single ant, or group of ants and rubs them on its feathers. The purpose of this behavior is not well understood. It is thought that birds may be able to aquire defensive secretions from the ant possibly used for some medicinal purpose. Also may be a supplement to the birds own preen oil.

Courtship

• Wild, circular courtship flights within territory, with the male chasing the female. In 1–2 days the flights become more leisurely.

Nesting

Nest Site: In the East, usually on the ground well hidden under a small tree, bush, fern, or in a natural depression. In the West generally nests above ground in a tree or shrub, conifer sapling, or on top of a stump or log. There are some accounts of nests under the eaves of a building or on a rock ledge. Generally found near an edge or gap rather than in the interior of a forest.

Height: On the ground or typically an average of 2–8 feet (0.5–2.4 meters) above ground, has been recorded from 1.5 to 30 feet (0.5–9 meters).

Nest: The female builds the nest alone. Compact but bulky nest made of twigs, bark strips, mosses, ferns, and grasses. Lined with conifer needles, rootlets, and plant fibers.

Eggs: 3–4, oval or long oval. Pale blue, typically unmarked with a slight gloss. Similar to the eggs of the Veery, but paler blue.

Incubation period: Incubation by the female alone for 12–13 days. Male feeds the female on the nest. Male also guards his territory by perching on a dead snag or a branch of a conifer about 40 feet (12 meters) from the nest and sings frequently.

Nestling period: Nestlings altricial (born naked or with a small amount of down, eyes closed, unable to move or feed themselves). Parents both feed the young and keep the nest clean. Eyes open at 3–4 days, feather plumes erupt from the sheaths at 7 days, and young leave the nest after 10–12 days.

Fledgling period: Parents coax young to leap from the nest to the ground to be fed upon first fledging. No information on how long the parents feed the young out of the nest.

Broods: Double brooded. A study done in Massachusetts found that they are sometimes triple-brooded.

Cowbird Parasitism: Parasitised by cowbirds, but more information is needed concerning the effect of brood parasitism.