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The
American Bittern’s vocal performance starts with several snaps
of its bill. After this call to attention, the bittern follows with
a three-note "song" that carries over half a mile through its marsh
home. "Pump-er-lunk," it sings, starting with head and neck raised
upward and then throwing both forward like a fly-fisherman casting a
lure.
If a male succeeds in luring in a female with its song, a courtship
dance ensues that features white feathers erected as a kind of ruff
around the neck. Males are apparently polygamous.
Unlike their showy cousins the herons and egrets, American Bitterns
are secretive creatures, cryptically colored to hide within the bulrushes
and cattails of marshes. When threatened, bitterns pose motionless with
their bill held straight up. This would seem to make it impossible for
the bitterns to watch the movements of a predator, but their eyes are
placed low on their heads. Even with bill thrust skyward, they can still
look past it and forward.
Standing in this awkward position, bitterns maintain the illusion of
a stake or cattail stalk. The sneaky birds may even rotate their bodies
to make sure a viewer only sees their vertically striped white throats
and necks. Even more amazingly, they are reported to sway in synchrony
with surrounding marsh plants caught in the wind.
American Bitterns are not picky eaters. They will eat almost any kind
of small animal that they encounter in the marsh or surrounding grasslands.
Small fish and frogs are prominent in their diet, as well as lizards
and small snakes, rodents, crayfish, mollusks, and insects. Bitterns
slowly stalk their prey and after long periods of standing motionless,
they strike lightning fast with their spear-like bills.
American Bitterns arrive on breeding grounds from mid-March to early
May and establish territories. Males often return to previously used
home ranges. Nests may be placed both in the marsh grasses and cattails
of a wetland or wet meadow and in the drier grassland as far as 100
yards from water. The nest is constructed primarily by the female, who
also incubates the eggs. Nestlings are fed regurgitated food and leave
the nest after about two weeks.
American Bitterns are found throughout most of Canada and the United
States from the southern Northwest Territories to south-central California
in the West and from southern New Brunswick to South Carolina in the
East. They rely on semi-permanent or permanent wetlands with tall emergent
vegetation. Ideal habitat typically includes a marsh with open water
in the center, and adjacent grassland. In fall most American Bitterns
migrate to winter ranges as far south as Central America.
Description:
American Bitterns are stocky, relatively short-legged and long-necked
herons. The upperparts are streaky brown and buffy colored. The underparts
are boldly striped with brown longitudinally and the throat is white
outlined by a dark malar stripe. The bill is long and pointed. In flight
the paler wing coverts contrast with the dark wing tips and primaries.
Recording credit:
The American Bittern songs were recorded by Gregory F. Budney and Steven
R. Pantle, MLNS Catalog # 53166. Recordings of the American Bittern
can also be found on our
Diversity of Animal Sounds CD available at our online
Cornell Lab
Birding Shop.
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