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Size:
14-1/2" long.
Price:
$109.00 US
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Description:
Western
Grebes are large and slender with long necks and long, thin bills.
Plumage is dark gray above and white below, with a clear color
division. The top of the face is black, and the bottom white.
The black extends below the eye in the Western Grebe. (In the
closely related and similar-appearing Clark's Grebe, the black
ends above the eye.) The bill of the Western Grebe is yellowish
to dull olive.
Habitat:
In
winter Western Grebes are found mostly on saltwater bays. During
the breeding season they are found on freshwater wetlands with
a mix of open water and emergent vegetation. The breeding areas
are located in the central arid steppe and Big Sage/Fescue zones
stretching from California north and east to south-central Canada.
Behavior:
Western
Grebes are highly gregarious in all seasons, wintering in large
flocks and nesting in colonies. The neck structure of Western
Grebes allows them to thrust their beaks forward, like spears,
a motion they use to catch prey. As a family, grebes are known
for their elaborate courtship displays. Western Grebes and the
closely related Clark's Grebes perform the most spectacular displays
of the family. The displays of Western and Clark's Grebes are
almost identical; the only apparent difference is that one of
many calls differs in the number of notes.
Diet:
In
all seasons and habitats, the primary food of Western Grebes
is fish.
Nesting:
Together,
the male and female Western Grebe build a floating nest made
of heaps of plant material anchored to emergent vegetation in
a shallow area of a marsh. The female lays three to four eggs,
and both parents incubate. Once hatched, the young leave the
nest almost immediately and ride on the backs of the parents.
Both parents feed the young. Young are plain gray and white,
not striped like the young of other grebes.
Migration
Status:
Many
birds from the northern part of the population migrate at night
to the Pacific Ocean.
Conservation
Status:
At
the turn of the 20th Century, tens of thousands of Western and
Clark's Grebes were killed for their feathers. With protection,
they have recovered and can now be found breeding in new areas
not occupied historically. Fluctuating water levels, oil spills,
gill nets, and poisons such as rotenone (used to kill carp) are
factors that negatively affect the population. When approached
by humans, the parents will leave the nest, leaving eggs vulnerable
to predation and the elements. Thus, areas frequently disturbed
by humans may have low productivity.
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