Saturday, June 22, 2013

Tundra Swan

Tundra Swan


Cygnus columbianus
Photo: Tundra swan swimming in water
The graceful tundra swan feeds not only on underwater flora and shellfish but has developed a taste for grains and corn, much to the chagrin of farmers.
Photograph by Bates Littlehales
The snowy white tundra swan breeds in the Arctic and migrates many miles to winter on North America's Atlantic and Pacific coastlines, bays, and lakes. The eastern population frequents the Chesapeake Bay and North Carolina, while the western population typically winters in California. These animals fly some 3,725 miles (6,000 kilometers) round-trip between their distant habitats, and make the daunting journey twice each year. Tundra swan subspecies also winter in Europe and Asia.
Tundra swans are often confused with trumpeter swans, and indeed the two species are very similar in appearance. They are most easily distinguished by their calls.
Tundra swans winter on the water and sleep afloat. They are strong and speedy swimmers that take to the air with a running start, clattering across the water's surface with wings beating. In flight, the rhythmic flapping of the swan's wings produces a tone that once earned it the name "whistling swan."
These large birds feed by dipping their heads underwater to pluck aquatic plants, tubers, and roots. They also eat shellfish and are developing an increasing taste for grains and corn found in farmland areas.
Believed to mate for life, these swans actually pair up for nearly an entire year before breeding. Though in their winter grounds they gather in huge flocks, they breed as solitary pairs spread out across the tundra. Each couple defends a territory of about three-fourths square miles (two square kilometers).
The bird's tundra nests are large stick dwellings lined with moss and grasses. Ideally, they are situated close to a pond or other water source.
Females typically lay about four eggs and incubate them for 32 days while males guard the nest. Young chicks are protected from cold and predators, including swarms of voracious Arctic mosquitoes. Tundra swans can be nasty when aroused, and the birds may even be able to fend off predators like foxes and jaegers.

1 comment:

Related Posts Plugin for WordPress, Blogger...