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Range and Habitat: After many years of protection, the
species is still confined to small, isolated areas in Alaska,
British Columbia, Alberta, Wyoming and Montana. The trumpeter
has been re-introduced into Minnesota and Wisconsin. Trumpeters
inhabit shallow, sheltered and preferably fresh waters.
Habits and Adaptations: Courtship is slow and displays
have great significance. Swans usually mate for life. Unlike most
other waterfowl, both sexes participate in building the nest.
A mated pair will vigorously defend the mating, nesting and cygnet
feeding grounds. Females usually begin their wing molt from 1-3
weeks before the eggs hatch, while the males of breeding pairs
usually begin to molt before hatching also, although some molt
afterwards. Most communication is through visual displays. Waterfowl
have monocular vision - each eye is used independently for lateral
views.
Diet: A variety of marsh and aquatic freshwater plants
compose the bulk of the food consumed.
Breeding and Maturation: In Alaska, spring arrival is
in late March or April. Egg laying normally commences in late
April or early May and is completed in mid-May with a normal clutch
size of 4-5 eggs. Both parents attend the nest but only the female
incubates. Incubation period varies from 33-37 days. Hatching
requires about 2 days. The cygnet uses a thorn-like projection
on the tip of the upper mandible - the egg tooth - to break through
the shell. Cygnets are closely attended by both parents until
the cygnets reach flight age.
Miscellaneous: Today the trumpeter is legally protected
throughout the entire year, and it was removed from the list of
endangered species only a few years ago. Successful establishment
of breeding populations in several western refuges suggest that
at least remnant populations of trumpeters can be maintained in
these areas where there is protection and available habitat.
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