Marine mammals are a diverse group of roughly 120 species of mammal Mammals are a class of vertebrate, air-breathing animals whose females are characterized by the possession of mammary glands while both males and females are characterized by sweat glands, hair and/or fur, three middle ear bones used in hearing, and a neocortex region in the brain that are primarily ocean An ocean (from Greek Ωκεανός, Okeanos ) is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface (~3.61 X 1014 m2) is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas-dwelling or depend on the ocean for food. They include the cetaceans The order Cetacea (pronounced /sɨˈteɪʃə/, L. cetus, whale, from Greek) includes whales, dolphins, and porpoises. Cetus is Latin and is used in biological names to mean "whale"; its original meaning, "large sea animal", was more general. It comes from Ancient Greek κῆτος (kētos), meaning "whale" or " (whales Whale is the common name for marine mammals of the order Cetacea. The term whale is sometimes used to refer to all cetaceans, but in more common English usage it generally excludes the members of the Delphinoidea superfamily, such as dolphins and porpoises. These smaller species belong to the suborder Odontoceti , which also includes the sperm, dolphins Dolphins are marine mammals that are closely related to whales and porpoises. There are almost forty species of dolphin in seventeen genera. They vary in size from 1.2 m and 40 kg (90 lb) (Maui's Dolphin), up to 9.5 m (30 ft) and 10 tonnes (9.8 LT; 11 ST) (the Orca or Killer Whale). They are found worldwide, mostly in the shallower seas of the, and porpoises Porpoises are small cetaceans of the family Phocoenidae; they are related to whales and dolphins. They are distinct from dolphins, although the word "porpoise" has been used to refer to any small dolphin, especially by sailors and fishermen. The most obvious visible difference between the two groups is that porpoises have flattened,), the sirenians Sirenia is an order of fully aquatic, herbivorous mammals that inhabit swamps, rivers, estuaries, marine wetlands, and coastal marine waters. Four species are living, in two families and genera. These are the dugong (1 species) and manatees (3 species). Sirenia also includes Steller's sea cow, extinct since the 18th century, and a number of taxa (manatees Manatees are large, fully aquatic marine mammals sometimes known as sea cows. The name manatí comes from the Taíno, a pre-Columbian people of the Caribbean, meaning "breast". They contain three of the four living species in the order Sirenia, the other being the dugong, which is native to the Eastern Hemisphere. The Sirenia are thought and dugong The dugong is a large marine mammal which, together with the manatees, is one of four living species of the order Sirenia. It is the only living representative of the once-diverse family Dugongidae; its closest modern relative, Steller's Sea Cow (Hydrodamalis gigas), was hunted to extinction in the 18th century. It is also the only sirenian in its), the pinnipeds Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semi-aquatic marine mammals comprising the families Odobenidae (the walrus), Otariidae (eared seals, including sea lions and fur seals), and Phocidae (earless seals). Formerly classified as a separate biological suborder, Pinnipedia is now sometimes considered a (true seals, eared seals The eared seals or otariids are marine mammals in the family Otariidae, one of three groupings of Pinnipeds. They comprise 16 species in seven genera commonly known either as sea lions or fur seals, distinct from true seals and the Walrus (odobenids). Otariids are adapted to a semi-aquatic lifestyle, feeding and migrating in the water but breeding and walrus The walrus is a large flippered marine mammal with a discontinuous circumpolar distribution in the Arctic Ocean and sub-Arctic seas of the Northern Hemisphere. The walrus is the only living species in the Odobenidae family and Odobenus genus. It is subdivided into three subspecies: the Atlantic Walrus (O. rosmarus rosmarus) found in the Atlantic), and several otters (the sea otter The sea otter is a marine mammal native to the coasts of the northern and eastern North Pacific Ocean. Adult sea otters typically weigh between 14 and 45 kg (30 to 100 lb), making them the heaviest members of the weasel family, but among the smallest marine mammals. Unlike most marine mammals, the sea otter's primary form of insulation is an and marine otter Marine Otters are rare and poorly-known marine mammals of the weasel family (Family Mustelidae). They are the most exclusively marine species of the otters of South America, and rarely even venture into freshwater or estuarine habitats. The scientific name means "otter cat," and in Spanish, Marine Otters are often referred to as "). The polar bear The polar bear is a bear native largely within the Arctic circle encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. It is the world's largest carnivore species found on land. It is also the largest bear, together with the omnivore Kodiak bear which is approximately the same size. An adult male weighs around 350–680, while not aquatic, is also usually considered a marine mammal because it lives on sea ice Sea ice is largely formed from ocean water that freezes. Because the oceans consist of saltwater, this occurs at about -1.8 °C for most or all of the year.
Marine mammals evolved from land dwelling ancestors and share several adaptive features for life at sea such as generally large size, hydrodynamic In physics, fluid dynamics is a sub-discipline of fluid mechanics that deals with fluid flow—the natural science of fluids in motion. It has several subdisciplines itself, including aerodynamics (the study of air and other gases in motion) and hydrodynamics (the study of liquids in motion). Fluid dynamics has a wide range of applications, body shapes, modified appendages An appendage in the broadest sense is an additional or subsidiary part existing on, or added to, something which can generally still function if the appendage has never existed or is later provided or grown, or will still perform a primary function if the appendage is removed and various thermoregulatory Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. This process is one aspect of homeostasis: a dynamic state of stability between an animal's internal environment and its external environment . If the body is unable to maintain a normal adaptations. Different species are, however, adapted to marine life to varying degrees. The most fully adapted are the cetaceans and the sirenians, which cannot live on land.
Despite the fact that marine mammals are highly recognizable charismatic megafauna, many populations are vulnerable or endangered An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters. Also it could mean that due to deforestation there may be a lack of food and/or water. The International Union for Conservation of Nature has calculated the due to a history of commercial exploitation for blubber Blubber is a thick layer of vascularized fat found under the skin of all cetaceans, pinnipeds and sirenians, meat Meat is animal flesh that is used as food. Most often, this means the skeletal muscle and associated fat, but it may also describe other edible tissues such as organs, livers, skin, brains, bone marrow, kidneys, or lungs. The word meat is also used by the meat packing industry in a more restrictive sense—the flesh of mammalian species raised and, ivory Ivory is formed from dentine and constitutes the bulk of the teeth and tusks of animals such as the elephant, hippopotamus, walrus, mammoth and narwhal and fur Fur is a synonym for hair, used more commonly in reference to non-human animals, usually mammals; particularly those with extensive body hair coverage. The term is sometimes used to refer to the body hair of an animal as a complete coat, also known as the "pelage". Fur is also used to refer to animal pelts which have been processed into. Most species are currently protected from commercial exploitation.
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Belfast Telegraph
The company has now been granted permission to operate the turbine without any environmental scientists on board to watch for marine mammals . ...
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opencongress.org
Mon, 06 Jul 2009 00:00:00 GM
Official government data, breaking news and blog coverage, public comments and user community for S.1395 A bill to amend the . Marine Mammal. Protection Act of 1972 to allow importation of polar bear trophies taken in sport hunts in Canada ...
