Sea otter - Wikipedia. The sea otter (Enhydra lutris) is a marine mammal native to the coasts of the northern and eastern North Pacific Ocean. Adult sea otters typically weigh between 1. Unlike most marine mammals, the sea otter's primary form of insulation is an exceptionally thick coat of fur, the densest in the animal kingdom. Although it can walk on land, the sea otter lives mostly in the ocean. The sea otter inhabits offshore environments, where it dives to the sea floor to forage. It preys mostly on marine invertebrates such as sea urchins, various molluscs and crustaceans, and some species of fish. Its foraging and eating habits are noteworthy in several respects. First, its use of rocks to dislodge prey and to open shells makes it one of the few mammal species to use tools. Tastes something like iodine. Sendai people like it.' It looks nothing like a pineapple. Open source travel guide to Samoa, featuring up-to-date information on attractions, hotels, restaurants, nightlife, travel tips and more. Free and reliable advice. Find program websites, online videos and more for your favorite PBS shows. Antique Prints, Antique botanical prints & hand colored prints & bird prints, flower prints,fish & shell prints. Great quality & prices from top antique print dealer. In most of its range, it is a keystone species, controlling sea urchin populations which would otherwise inflict extensive damage to kelp forestecosystems. Its diet includes prey species that are also valued by humans as food, leading to conflicts between sea otters and fisheries. Sea otters, whose numbers were once estimated at 1. The recovery of the sea otter is considered an important success in marine conservation, although populations in the Aleutian Islands and California have recently declined or have plateaued at depressed levels. For these reasons, the sea otter remains classified as an endangered species. Taxonomy. Sea otter twin births are rare, and the high demands on the mother usually result in one pup being abandoned. Rodents (of which the beaver is one) are not closely related to otters, which are carnivores. It is not to be confused with the marine otter, a rare otter species native to the southern west coast of South America. A number of other otter species, while predominantly living in fresh water, are commonly found in marine coastal habitats. The extinct sea mink of northeast North America is another mustelid that had adapted to a marine environment. Evolution. It is unique among the mustelids in not making dens or burrows, in having no functional anal scent glands. The holotype, a lower carnassial, was in the Norwich Castle Museum but seems to be lost. Only one more specimen, an extremely worn lower carnassial, is known. However, reintroductions in 1. Washington coast were very successful and sea otters have been expanding their range since. They have now entered the Strait of Juan de Fuca and can be found almost as far east as Pillar Point. Individuals have even been seen in the San Juan Islands and northern Puget Sound. Get information, facts, and pictures about Ireland at Encyclopedia.com. Make research projects and school reports about Ireland easy with credible articles from our. Physical characteristics. Cold water is kept completely away from the skin and heat loss is limited. The nostrils and small ears can close. The front paws are short with retractable claws, with tough pads on the palms that enable gripping slippery prey. Kondakov. The sea otter propels itself underwater by moving the rear end of its body, including its tail and hind feet, up and down. The sea otter walks with a clumsy, rolling gait on land, and can run in a bounding motion. It must eat an estimated 2. Its relatively large kidneys enable it to derive fresh water from sea water and excrete concentrated urine. The shape of these different hair fibers connect to trap air between them. This allows them to maintain their body heat without the blubber other sea mammals use. It has a period of foraging and eating in the morning, starting about an hour before sunrise, then rests or sleeps in mid- day. To casual observers, it appears as if the animals are scratching, but they are not known to have lice or other parasites in the fur. Although it can hold its breath for up to five minutes. In this pouch (preferentially the left one), the animal stores collected food to bring to the surface. This pouch also holds a rock, unique to the otter, that is used to break open shellfish and clams. It can chew and swallow small mussels with their shells, whereas large mussel shells may be twisted apart. To pry an abalone off its rock, it hammers the abalone shell using a large stone, with observed rates of 4. A raft typically contains 1. To keep from drifting out to sea when resting and eating, sea otters may wrap themselves in kelp. The cry of a pup is often compared to that of a seagull. However, temporary pair- bonding occurs for a few days between a female in estrus and her mate. Georg Steller wrote, . Initially, the objects it retrieves are of little food value, such as brightly colored starfish and pebbles. The fur trade that began in the 1. In about two- thirds of its former range, the species is at varying levels of recovery, with high population densities in some areas and threatened populations in others. Sea otters currently have stable populations in parts of the Russian east coast, Alaska, British Columbia, Washington, and California, with reports of recolonizations in Mexico and Japan. After the years of the Great Hunt, the population in these areas, currently part of Russia, was only 7. Of these, about 1. Kurils, 2,0. 00 to 3,5. Kamchatka and another 5,0. Commander Islands. In 1. 97. 3, the population in Alaska was estimated at between 1. A remnant population survived off Vancouver Island into the 2. Kyuquot in 1. 92. From 1. 96. 9 to 1. Alaska to the west coast of Vancouver Island. This population expanded to over 3,2. Cape Scott in the north to Barkley Sound to the south. It is not known if this colony, which numbered about 3. Annual surveys between 2. Olympic Peninsula from just south of Destruction Island to Pillar Point. They can swim as close as six feet off shore along the Olympic coast. Reported sightings of sea otters in the San Juan Islands and Puget Sound almost always turn out to be North American river otters, which are commonly seen along the seashore. However, biologists have confirmed isolated sightings of sea otters in these areas since the mid- 1. California has almost 3,0. The historic population of California sea otters was estimated at 1. California's sea otters are the descendants of a single colony of about 5. Bixby Bridge in Big Sur in 1. There has been some contraction from the northern (now Pigeon Point) and southern limits of the sea otter's range apparently related to lethal shark bites. Fish and Wildlife Service (USFWS) relocated about 1. Californian sea otters to San Nicolas Island (SNI) in southern California, in the hope of establishing a reserve population should the mainland be struck by an oil spill. To the surprise of biologists, the San Nicolas sea otters mostly swam back to the mainland. To manage the competition between sea otters and fisheries, it declared an . In this zone, only San Nicolas Island was designated as sea otter habitat, and sea otters found elsewhere in the area were supposed to be captured and relocated. These plans were abandoned after many translocated otters died and also as it proved impractical to capture the hundreds of otters which ignored regulations and swam into the zone. Cooper, a sea captain from Boston, by Mexican Governor Juan Bautista Alvarado along with a license to hunt sea otters, reportedly then prevalent at the mouth of Corte Madera Creek. Cyanobacteria are found in stagnant freshwater enriched with nitrogen and phosphorus from septic tank and agricultural fertilizer runoff, and may be flushed into the ocean when streamflows are high in the rainy season. These are the first documented sightings of otters this far south in 3. In 1. 97. 0 and 1. Amchitka Island, Alaska to the Southern Oregon coast. However, this translocation effort failed and otters soon again disappeared from the state. This male is thought to have originated from a colony in Washington, but disappeared after a coastal storm. The lone male sea otter could have traveled from either California or Washington. In studies performed at Amchitka Island in the 1. Surprisingly, though, the diets of individuals were more specialized in these areas than in areas where food was plentiful. They keep the population of certain benthic (sea floor) herbivores, particularly sea urchins, in check. Sea urchins graze on the lower stems of kelp, causing the kelp to drift away and die. Loss of the habitat and nutrients provided by kelp forests leads to profound cascade effects on the marine ecosystem. North Pacific areas that do not have sea otters often turn into urchin barrens, with abundant sea urchins and no kelp forest. They remove mussels from rocks, liberating space for competitive species and thereby increasing the diversity of species in the area. Many predators find the otter, with their pungent scent glands, distasteful. Young predators may kill an otter and not eat it. Leading mammalian predators of this species include orcas and sea lions; bald eagles also prey on pups by snatching them from the water surface. In California, bites from sharks, particularly great white sharks, have been estimated to cause 1. Their beautiful fur is a main target for many hunters. Archaeological evidence indicates that for thousands of years, indigenous peoples have hunted sea otters for food and fur. Russia was also exploring the far northern Pacific at this time, and sent Vitus Bering to map the Arctic coast and find routes from Siberia to North America. The Russians found the sea otter far more valuable than the sable skins that had driven and paid for most of their expansion across Siberia. If the sea otter pelts brought back by Bering's survivors had been sold at Kyakhta prices they would have paid for one tenth the cost of Bering's expedition. The Russians initially traded with the Aleuts inhabitants of these islands for otter pelts, but later enslaved the Aleuts, taking women and children hostage and torturing and killing Aleut men to force them to hunt. Many Aleuts were either murdered by the Russians or died from diseases the hunters had introduced. In 1. 79. 9, Emperor Paul I consolidated the rival fur- hunting companies into the Russian- American Company, granting it an imperial charter and protection, and a monopoly over trade rights and territorial acquisition.
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