Breast feeding web cam
Breast feeding web cam
The phalaropes are usually included as well, since although they are waders ("shorebirds" in North America), two of the three species are oceanic for nine months of the year, crossing the equator to feed pelagically.
While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations.
The Procellariiformes are unusual among birds in having a strong sense of smell, which is used to find widely distributed food in a vast ocean, Cormorants, like this double-crested cormorant, have plumage that is partly wettable.
This functional adaptation balances the competing requirement for thermoregulation against that of the need to reduce buoyancy.
This allows them to swim without fighting the buoyancy that retaining air in the feathers causes, yet retain enough air to prevent the bird losing excessive heat through contact with water.
The plumage of most seabirds is less colourful than that of land birds, restricted in the main to variations of black, white or grey.
They feed both at the ocean's surface and below it, and even feed on each other.
Seabirds can be highly pelagic, coastal, or in some cases spend a part of the year away from the sea entirely.There exists no single definition of which groups, families and species are seabirds, and most definitions are in some way arbitrary.In the words of two seabird scientists, "The one common characteristic that all seabirds share is that they feed in saltwater; but, as seems to be true with any statement in biology, some do not." However, by convention all of the Sphenisciformes and Procellariiformes, all of the Pelecaniformes except the darters, and some of the Charadriiformes (the skuas, gulls, terns, auks and skimmers) are classified as seabirds.The usually black wing tips help prevent wear, as they contain melanins to make them black that helps the feathers resist abrasion.Seabirds evolved to exploit different food resources in the world's seas and oceans, and to a great extent, their physiology and behaviour have been shaped by their diet.In the Paleogene the seas were dominated by early Procellariidae, giant penguins and two extinct families, the Pelagornithidae and the Plotopteridae (a group of large seabirds that looked like the penguins).