The Black Swan, (Cygnus atratus), is a bird of Australia,
including Tasmania.
Black Swans are from 44 to 55 inches with a wing span of 6
feet. The plumage is black, the tips of the wings are white.
Immature Black Swans are light grayish brown. Swans molt once
a year during which time they are flightless.
The bills are red and white with fine grooves that enable
them to feed on underwater plants. Their legs and webbed feet
are black. They do not dive for food but are able to reach the
plants they feed on with their long necks.
During February through September, the Black Swans begin building
their nests. These large birds, who mate for life, often nest
in colonies, unlike other swans. The nest is a large affair built
of sticks and vegetation. Both birds build the nest.
The female lays 4 to 8 pale green eggs. Both parents tend
the nest. The incubation period is about 35 - 40 days. The young
swans, called cygnets, are covered with a fluffy gray-colored
down that they keep for 3 - 4 weeks. The cygnets can swim soon
after hatching and learn to feed themselves. They also may ride
on their parent's back for longer trips into deeper water. The
young birds leave the family unit to begin lives of their own
in about nine months.