The Red-necked Grebe (Podiceps grisegena) is a migratory aquatic bird found in the temperate regions
of the northern hemisphere. Its wintering habitat is largely restricted
to calm waters just beyond the waves around ocean coasts, although some
birds may winter on large lakes. Grebes prefer shallow bodies of fresh water such as lakes, marshes or fish-ponds as breeding sites.
The Red-necked Grebe is a nondescript dusky-grey bird in winter.
During the breeding season, it acquires the distinctive red neck
plumage, black cap and contrasting pale grey face from which its name
was derived. It also has an elaborate courtship
display and a variety of loud mating calls. Once paired, it builds a
nest from water plants on top of floating vegetation in a shallow lake
or bog.
Like all grebes, the Red-necked is a good swimmer, a particularly
swift diver, and responds to danger by diving rather than flying. The
feet are positioned far back on the body, near the tail, which makes the
bird ungainly on land. It dives for fish or picks insects off
vegetation; it also swallows its own feathers, possibly to protect the
digestive system. The conservation status of its two subspecies—P. g. grisegena found in Europe and western Asia, and the larger P. g. holboelii in North America and eastern Siberia—is evaluated as Least Concern, and the global population is stable or growing.
The Red-necked Grebe breeds on small inland lakes in Canada and Alaska,
and winters along both coasts of North America. Boldly marked, vocal,
and aggressive during the breeding season, it is quiet and subtly
attired in winter.
Adult Description
Medium-sized waterbird; large grebe.
Bill is large, straight, and sharp.
Breeding adult has a rufous neck, pale gray or white cheeks, and a black cap.
Nonbreeding adult has gray neck and cheeks.
Immature Description
Juvenile
has bold dark stripes on sides of head. Immature similar to nonbreeding
adult, but even grayer; some rufous or brown tones usually show on
foreneck.
Facts
Like
other grebes, the Red-necked Grebe ingests large quantities of its
own feathers. Feathers remain in the bird's stomach. The function of
feathers in the stomach is unknown. One hypothesis suggests that the
feathers help protect the lower digestive tract from bones and other
hard, indigestible material.
The Red-necked Grebe also feeds its feathers to its young.
The
Red-necked Grebe migrates over land strictly at night. It sometimes
migrates over water or along coasts by day, in large flocks.
Habitat
Breeds on shallow freshwater lakes, bays of larger lakes, marshes, and
other inland bodies of water. Winters on open ocean or on large lakes.
Food
Fish, crustaceans, aquatic insects, and some mollusks and amphibians.
Nesting
Floating mound of plant matter with a depression in the middle; bulk of
nest is below water line. Nest is placed on aquatic vegetation,
sometimes in open water, and anchored to the lake bottom or submerged
logs.
Clutch Size
1–9 eggs
Egg Description
Light blue.
Condition at Hatching
Downy
and active; chicks immediately climb onto parent's back, where they
spend most of their time until they are 10 to 17 days old.
Behaviour
Pair bond is developed and maintained through highly complex, ritualized
courtship displays, including parallel rushes in upright positions and
mutual presentation of green weeds.Pairs defend their territories with
various threat displays, including spreading of wings, hunching, raising
heads, or thrusting bills forward.Dives under water for food. Locates
prey by sight. Captures prey by grasping with bill.
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