Wednesday, December 28, 2011

The Giant Trumpeter Swan

An increasingly common winter sight at many lakes and rivers in the United States are flocks of giant trumpeter swans. Trumpeter swans are both the largest native North American birds and the largest living waterfowl species on earth. Exceptionally sized individuals can have a total body length of six feet, wingspan of ten feet, and weigh 38lbs!
The largest number of these long-necked birds can be found in Alaska, with native populations migrating to locations throughout portions of central and western Canada and the United States seasonally. Populations that have been introduced by conservation efforts are usually year-round residents and do not migrate.

Trumpeter swans primarily feed on all manner of aquatic plants and vegetation. They often feed by upending themselves in the water and using their long necks to reach underwater plants; this technique is known as “dabbling”. In the winter, trumpeter swans will also take advantage of any remaining seeds or grains left in agricultural fields, though they prefer aquatic dining. Trumpeter swans will usually continue to nest and feed at a lake, pond or river in the winter so long as food and open water remains, often sharing their habitat with much smaller Canada geese. Once suitable wintering grounds are found, trumpeter swans may continue to return to the same site each winter for life.
Courtesy Missouri Department of Conservation
Trumpeter swan pairs usually mate for life at 4-7 years of age. They are a long-lived species, with many wild swans living well into their twenties. Because of their size, adults have no real natural predators other than golden eagles. Human hunting in the 1800’s caused the trumpeter swan to nearly become extinct. Since the early twentieth century there have been conservation efforts in place in many states that have been effective to the point that these giant swans are now once again common in some areas.

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