| Species: Hermit Thrush
Catharus bicknelli
Description:
With spotted breast
and reddish tail, the Hermit Thrush lives up to its name. It is a
quiet and unobtrusive bird that spends much of its time in the lower
branches of the undergrowth or on the forest floor, often seen
flicking its wings while perched and quickly raising and slowly
lowering its tail. This thrush is one of the most widely distributed
forest-nesting migratory birds in North America. Its extensive
breeding range includes the northern hardwood forest, as well as
most of the boreal and mountainous coniferous forest areas north of
Mexico. In migration, the species moves southward and spreads out to
winter over much of the southern United States, through Mexico to
Guatemala. It is the only species of Catharus that winters in North
America, switching from a breeding diet of mainly arthropods to a
wintering diet heavily supplemented with fruits.
Identification:
General: A
short distance migrant the Hermit Thrush is the only member of the
Catharus thrushes to spend the winter in North America. A summer
insectivore it changes its diet in the winter to equal parts of
insects and fruit in winter.
A highly variable
species in color and size, the Hermit Thrush’s morphological
characteristics and plumage have been well studied: up to 13
different races. Hermit Thrush is a medium-sized thrush 6.75 inches
long 31 gr (length of skins 144–183 mm). Distinguished by rufescent
tail (especially toward base) and longer uppertail-coverts that
contrast distinctly with remaining upperparts. Thin, whitish
eye-ring and weakly defined whitish bar over lores. Base color of
underparts typically whiter and spots on upper breast generally
larger and rounder than on similar Catharus . In hand, 10th primary
is longer than primary-coverts, 9th primary shorter than 6th, and
6th primary emarginated.
Adult: Males
and females are similar with brown backs, reddish tails, black spots
on the breast and a thin, white eyering. The behaviour of Hermit
Thrush helps identify it as it cocks its tail up and flicks its
wings frequently often quickly raising its tail and then slowly
lowering it.
Similar Species:
other spotted thrushes especially Swainson’s Thrush Catharus
ustulatus. Swainson’s Thrush, especially the browner, more rufescent
Pacific races, “Russet-backed Thrushes,” sometimes confused with
Hermit Thrush, but Swainson’s has bolder, distinctly buff eye-ring
and line over lores, and strong buff wash to lower cheeks and
breast.
Behavior:
Habit of cocking tail upward and flicking wings (tail lifted rapidly
and lowered slowly) is distinctive among similar Catharus species.
Habitat:
Uses broad spectrum of forested and edge habitat. Described as
forest interior bird that favors internal forest edges. For example:
margins of pond or meadow within forest patch; small clearings
within wooded areas created by disturbances such as logging,
drilling, road-building, utility cuts, wind, and fire; and mountain
bogs and glades bordered by native or transplanted conifers.
Information:
For such a widely
distributed species, surprisingly little is known about basic
demographic characteristics such as life span, basic breeding
biology and factors that influence reproduction and survival, and
fidelity to breeding and wintering areas. Even the well-known song
has been little studied.
Conservation
Status:
BC Yellow, COSEWIC
n/a, Global G5 (2008). As the only Catharus thrush that does not
winter exclusively in the Neotropics, Hermit Thrush is partly spared
adverse impacts of Neotropical deforestation, implicated in recent
population declines of some North American songbirds. For this
species, loss and/or fragmentation of wintering and nesting habitat
in Canada, the U.S., and Mexico may be of concern.
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