The eastern population frequents the Chesapeake Bay and North Carolina, while the western population typically winters in California. These animals fly some 3, miles 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. 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. While some species are more docile, many are quite territorial and aggressive towards humans, other birds, and virtually anything. They spend their days drifting across the water and dabbling for food, or walking on land and picking at the grass and plants. When they are breeding, Swans become very protective of their nests, mates, and cygnets.
Most of these birds are monogamous, and breed with the same partner year after year. The pair builds a large nest, usually out of grasses, reeds, small branches, and vegetation. Females lay between four and seven eggs per clutch. Depending on the species, incubation lasts anywhere from a month to a month and a half. The cygnets stay under the watchful eye of their parents until they are about a year old. These birds are present in many different cultures, artistic renditions, and even coins!
This is just one example of Swans in human culture. It is no surprise that these birds are readily adopted into human habitation, parks, and gardens because they are incredibly beautiful and graceful. Animals Network. Anseriformes Anatidae Aves Chordata Cygnus. Red Angus. There are seven species of swans, occurring on all continents except Antarctica.
Three species of swan, the mute swan Cygnus olor , the tundra swan C. Swans have a very long neck, and all North American species have a white body. However, mute swans compete with other swans for food because they feed in similar ways.
Mute swans are large and aggressive birds. As adults they are not often preyed on unless they are old or ill. Eggs and hatchlings are vulnerable to nest predation by raccoons , mink , and a wide variety of other medium to large-sized predators. But swan parents are typically present to protect their young. Mute swans impact aquatic vegetation communities through their grazing.
Swans may attack people who approach their nests too closely. There are records of them knocking boaters off of jet skis. An adult swan can seriously injure children. In addition, mute swans are thought to pose a threat to native wildlife as a result of competition for food, territories, and nesting areas. Mute swans were domesticated for food in Britain.
Markings on their feet indicated ownership. Eventual domestication saved the bird from becoming hunted to extinction there. Feathers were also used as quills for writing, the leathery web used for purses, and the wing bones for making whistles. The successful introduction and expansion of mute swans into North America may pose significant concerns to native wildlife. Common loons threatened in Michigan and recently re-introduced trumpeter swans are two species of primary concern.
The North American population of mute swans has been increasing steadily since its introduction. These birds are aggressive, and have been known to drive off such stubborn and similarly sized species as Canada geese and trumpeter swans. Wildlife managers seek to control non-native mute swans in areas where native wildlife is being threatened.
Granlund, J. The Birds of Michigan. Indiana University Press, Indianapolis, Halton, W. Reilly, E. Terres, J.
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