Seabirds
Sea Birds
Huge numbers of birds live by, or, on the sea. Some feed along the shore or dive for fish in coastal waters such as various gulls, cormorants and gannets. Others like auks, terns, skuas and frigate birds live for weeks far out in the sea. They come to the surface occasionally to calm waters to float and rest. Still others, like albatrosses, shearwaters and petrels, spend weeks at a time flying in air. They land, only rarely, usually to breed. They are superb flyers, soarers across the oceans for thousands of kilometers.
Albatrosses may be at sea for 2 to 3 weeks at a time. The wandering albatross has the longest wingspan of any bird at upto 3.5m. Other albatrosses, like the waved albatross, have slightly smaller wings.
There are about 90 species of gulls, skuas and terns. They usually wheel and call along the coast, but gulls especially have adapted to food far inland. They hunt for worms and grubs in the freshly ploughed fields and squabble over leftovers on rubbish tips especially in winters . The herring gull, in particular, is aggressive and threatens other birds. Gulls eat almost anything including fish, crabs, insects, rotten meats and the eggs of other birds.
Seagulls has strong body, elongated legs and webbed feet. Beak is slightly hooked and usually yellow in color. Seagulls are one of the rare animals that are able to drink salt water. They have special glands (located above the eyes) which eliminate excess salt from the body. They use the winds to stay aloft without flapping.
Most gulls have white and grey plumage, matching the reflection of sunlight on the sea. Some species have black markings on the back, wings and head. The larger gulls, like the great black -backed gull, have heavy hooked beaks. They can easily kill smaller birds, baby rabbits and similar prey.
Pirates among birds
Skuas resemble larger gulls and have fearsome hooked beaks. In North America, they are known by the German name jaeger, meaning hunter due to their habit of chasing other birds who are carrying food. They harass the other bird, force it to drop its meal, then swoop to steal it. Big skuas like the great dkua msy catch and kill birds even larger than themselves.
The sea bird Tern is known for its long distance flying . The Arctic Tern flies 40,000 km each year! They spend the northern summer in the Arctic where they breed. At the end of the summer, they migrate all the way to Antarctica in time for the southern summer. So they live almost in daylight!
Terns are like slim graceful gulls. Many have forked tails earning them the nickname of ' Sea Swallows'. Many terns catch their fish prey by plunge-diving straight down into the water. They are mainly summer visitors to temperate regions migrating to warmer areas to avoid the cold winter flying.
The predating seabird Skuas
Skimming Along
Skimmers are tern like birds with an unusual feature. The lower mandible (part of the beak) is longer than the upper part. The skimmers flies low and dip this lower mandible in the water, to snatch any fish.
Masters of Ocean Winds
Albatrosses and petrels are master flyers feeding far out at sea. Albatrosses are so big and heavy that they usually need a cliff to leap from or a headwind to launch themselves into the air. Once aloft, they glide for hours in winds and air currents without flapping. Shearwaters are smaller but have similar bodies with long, narrow wings. Storm petrels are smaller and darker.
Plump Divers
Auks are plump seabirds resembling penguins. Their tight feathering keep the body warm and water out. They spend much time diving for food. Guillemots and razorbills breed in colonies on rocky ledges and cliffs where most predators cannot reach.
Cormorants are related to pelicans and have a similar but smaller throat pouch. Their feet are webbed across all four toes. They sreblack or dark birds experts at diving and swimming after fish. They prefer rocky coasts , unusually for seabirds, the oily waterproofing on their feathers is not very effective. So they spend long periods sitting with their wings spread out to dry in the sun.
The puffin is a strange looking seabird that nests in clifftop burrows. Its brightly pattern beak is large enough to hold a dozen small fish such as sea-eels.
Frigatebirds
Frigatebirds that live along the tropical coasts are among the most graceful seabirds. The magnificent frigatebird has long wings and a long tail which it uses as an aerial rudder and air-brake. it can swoop to catch fish leaping above the surface or snatch baby turtles hatching from their eggs on the beach.
The word frigatebird derives from the French mariners' name for the bird La Frégate - a frigate or fast warship. The etymology of the name was given by French naturalist Jean-Baptiste du Tertre when describing the magnificent frigatebird in 1667. English mariners referred to frigatebirds as Man-of-War birds.
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Excellent collection. Keep doing such publications on Birds.
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