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63-564: The Okhotsk High is a semi-permanent high pressure system that forms over the Sea of Okhotsk during the summer months. Its associated air mass is maritime polar , marked with frequent sea fog over ocean areas, and cool and moist conditions over land. It typically dominates the weather pattern over eastern Russia , northern Japan and the Korean Peninsula during the spring and summer months. This climatology -related article

126-833: A United Nations subcommittee accepted the Russian argument, and in March 2014 the full United Nations Commission on the Limits of the Continental Shelf ruled in favor of the Russian Federation. Bowhead whales were first caught in 1847, and dominated the catch between 1852 and the late 1860s. Between 1850 and 1853 the majority of the fleet went to the Bering Strait region to hunt bowheads, but intense competition, poor ice conditions, and declining catches forced

189-594: A company working for the Russian energy giant Gazprom . Sea lions Eumetopias Neophoca Otaria Phocarctos Zalophus Sea lions are pinnipeds characterized by external ear flaps , long foreflippers, the ability to walk on all fours, short and thick hair, and a big chest and belly. Together with the fur seals , they make up the family Otariidae , eared seals . The sea lions have six extant and one extinct species (the Japanese sea lion ) in five genera . Their range extends from

252-410: A direct effect on their on land breeding activity. Their seasonal abundance trend correlates with their breeding period between the austral summer of January to March. Their rookeries populate with newborn pups as well as male and female otariids that remain to defend their territories. At the end of the breeding period males disseminate for food and rest while females remain for nurturing. Other points in

315-667: A given species tend to be smaller in the tropics, increase in size with increasing latitude, and reach a maximum in sub-polar regions. In a cool climate and cold waters there should be a selective advantage in the relative reduction of body surface area resulting from increased size, since the metabolic rate is related more closely to body surface area than to body weight. Sea lions, with three groups of pinnipeds, have multiple breeding methods and habits over their families but they remain relatively universal. Otariids, or eared sea lions, raise their young, mate, and rest in more earthly land or ice habitats. Their abundance and haul-out behavior have

378-414: A long period of time and prevent side effects of high pressure at depth. The high pressures associated with deep dives cause gases such as nitrogen to build up in tissues which are then released upon surfacing, possibly causing death. One of the ways sea lions deal with the extreme pressures is by limiting the amount of gas exchange that occurs when diving. The sea lion allows the alveoli to be compressed by

441-746: A sea lion until he was rescued by the Coast Guard . Sea lions have also been a focus of tourism in Australia and New Zealand. One of the main sites to view sea lions is in the Carnac Island Nature Reserve near Perth in Western Australia. This tourist site receives over 100,000 visitors, many of whom are recreational boaters and tourists, who can watch the male sea lions haul out on to the shore. They have sometimes been called "the unofficial welcoming committee of

504-627: A speed of about 30 knots (56 km/h; 35 mph). Three species, the Australian sea lion , the Galápagos sea lion and the New Zealand sea lion , are listed as endangered . Sea lions are related to walruses and seals. Together with the fur seals , they constitute the family Otariidae , collectively known as eared seals. Until recently, sea lions were grouped under a single subfamily called Otariinae, whereas fur seals were grouped in

567-421: A speedboat. The sea lion appeared to be preparing for a second attack when the girl was rescued. An Australian marine biologist suggested that the sea lion may have viewed the girl "like a rag doll toy" to be played with. In San Francisco , where an increasingly large population of California sea lions crowds docks along San Francisco Bay, incidents have been reported in recent years of swimmers being bitten on

630-448: A week births consist most usually of one pup with a perinatal period of 3 to 13 days. Steller sea lions have exhibited multiple competitive strategies for reproductive success. Sea lion mating is often polygamous as males usually mate with different females to increase fitness and success, leaving some males to not find a mate at all. Polygamous males rarely provide parental care towards the pup. Strategies used to monopolize females include

693-451: Is 1.8 m (6 ft) long. The largest sea lions are Steller's sea lions , which can weigh 1,000 kg (2,200 lb) and grow to a length of 3.0 m (10 ft). Sea lions consume large quantities of food at a time and are known to eat about 5–8% of their body weight (about 6.8–15.9 kg (15–35 lb)) at a single feeding. Sea lions can move around 16 knots (30 km/h; 18 mph) in water and at their fastest they can reach

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756-522: Is a stub . You can help Misplaced Pages by expanding it . Sea of Okhotsk The Sea of Okhotsk covers an area of 1,583,000 square kilometres (611,000 sq mi), with a mean depth of 859 metres (2,818 ft) and a maximum depth of 3,372 metres (11,063 ft). It is connected to the Sea of Japan on either side of Sakhalin: on the west through the Sakhalin Gulf and the Gulf of Tartary ; on

819-400: Is surpassing the fertility rate by far. Since most pups are unable to reach the age of reproduction, the population is not growing fast enough to keep the species out of endangerment. Other parasites, like Anisakis and heartworm , can also infect sea lions. Australian sea lions ( Neophoca cinerea ) are also being affected by more frequent parasitic infections. The same method was used for

882-457: The subarctic to tropical waters of the global ocean in both the Northern and Southern Hemispheres , with the notable exception of the northern Atlantic Ocean . They have an average lifespan of 20–30 years. A male California sea lion weighs on average about 300 kg (660 lb) and is about 2.4 m (8 ft) long, while the female sea lion weighs 100 kg (220 lb) and

945-701: The 1640s. The Dutch captain Maarten Gerritsz Vries in the Breskens entered the Sea of Okhotsk from the south-east in 1643, and charted parts of the Sakhalin coast and Kuril Islands, but failed to realize that either Sakhalin or Hokkaido are islands. During this period, the sea was sometimes known as the Sea of Kamchatka . The first and foremost Russian settlement on the shore was the port of Okhotsk , which relinquished commercial supremacy to Ayan in

1008-475: The 1840s. The Russian-American Company all but monopolized the commercial navigation of the sea in the first half of the 19th century. The Second Kamchatka Expedition under Vitus Bering systematically mapped the entire coast of the sea, starting in 1733. Jean-François de Galaup, comte de Lapérouse and William Robert Broughton were the first non-Russian European navigators known to have passed through these waters other than Vries. Ivan Krusenstern explored

1071-461: The Chilean coast with a population estimate of 165,000. According to the most recent surveys in northern and southern Chile the sealing period of the middle twentieth century that left a significant decline in sea lion population is recovering. The recovery is associated with less hunting, otariids rapid population growth, legislation on nature reserves, and new food resources. Haul-out patterns change

1134-659: The Russian EEZ, any country could fish there, and some began doing so in large numbers in 1991, catching perhaps as much as one million metric tons of pollock in 1992. This was seen by the Russian Federation as presenting a danger to Russian fish stocks, since the fish move in and out of the Peanut Hole from the Russian EEZ. The Russian Federation petitioned the United Nations to declare the Peanut Hole to be part of Russia's continental shelf . In November 2013,

1197-453: The Russian oil drilling rig Kolskaya capsized and sank in a storm in the Sea of Okhotsk, some 124 km (77 mi) from Sakhalin island, where it was being towed from Kamchatka . Reportedly, its pumps failed, causing it to take on water and sink. The platform carried 67 people, of which 14 were rescued by the Magadan and the tugboat Natftogaz-55 . The platform was subcontracted to

1260-401: The Sea of Okhotsk as a nesting site. The Okhotsk culture and the later Ainu people , a coastal fishing and hunter-gatherer people, were located around the lands surrounding the Sea of Okhotsk, as well as in northern Japan. Russian explorers Vassili Poyarkov (1639) and Ivan Moskvitin (1645) were the first Europeans to visit the Sea of Okhotsk (and, probably, the island of Sakhalin ) in

1323-463: The Sea of Okhotsk is the subject of the most famous novel of the Japanese writer Takiji Kobayashi , The Crab Cannery Ship (1929). The Peanut Hole (named for its shape) was an area of open ocean at the center of the Sea of Okhotsk, about 55 km (30 mi) wide and 480 km (300 mi) long, that was surrounded by Russia's exclusive economic zone (EEZ). Since the Peanut Hole was not in

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1386-632: The Southeast. A line running from Nosyappu Saki (Cape Noshap, 43°23'N) in the Island of Hokusyû (Yezo) through the Kuril or Tisima Islands to Cape Lopatka (South point of Kamchatka ) in such a way that all the narrow waters between Hokusyû and Kamchatka are included in the Sea of Okhotsk. Some of the Sea of Okhotsk's islands are quite large, including Japan's second-largest island, Hokkaido, as well as Russia's largest island, Sakhalin. Practically all of

1449-625: The abundance of sea lions at particular times of the day, month, and year. Patterns in migration relate to temperature, solar radiation, and prey and water resources. Studies of South American sea lions and other otariids document maximum population on land during early afternoon, potentially due to haul-out during high air temperatures. Adult and subadult males do not show clear annual patterns, maximum abundance being found from October to January. Females and their pups hauled-out during austral winter months of June to September. South American sea lions have been greatly impacted by human exploitation. During

1512-418: The animal know its available oxygen supply. Yet, the sea lions cannot avoid the effects of gradual CO 2 build-up which eventually causes the sea lions to spend more time at the surface after multiple repeated dives to allow for enough built up CO 2 to be expired. Galapagos sea lions ( Zalophus wollebaeki ) can be infected with Philophthalmus zalophi , an eye fluke. These infections have heavy impacts on

1575-453: The beginning of January through the month of May and lower temperatures throughout the rest of the year. Parasites surfaced in large numbers when the sea temperature was at its highest. Furthermore, data was collected by capturing sea lions in order to measure and determine their growth rates. Their growth rates were noted along with the citings of parasites which were found under the eyelid. The shocking results were that sea lions are affected by

1638-463: The blood, due to the unloading complications with CO 2 . However, having more than normal levels of CO 2 in the blood does not seem to adversely affect dive behavior. Compared to terrestrial mammals, sea lions have a higher tolerance to storing CO 2 which is what normally tells mammals that they need to breathe. This ability to ignore a response to CO 2 is likely brought on by increased carotid bodies which are sensors for oxygen levels that let

1701-406: The drastic effects humans have on their ecosystems. As a result, South American sea lions have been foraging at higher tropical latitudes than they did prior to human exploitation. Fishermen play a key role in the endangerment of sea lions. Sea lions rely on fish, like pollock, as a food source and have to compete with fishermen for it. When fishermen are successful at their job, they greatly reduce

1764-440: The eastern coast of Sakhalin in 1805. Mamiya Rinzō and Gennady Nevelskoy determined that Sakhalin was indeed an island separated from the mainland by a narrow strait. The first detailed summary of the hydrology of the Sea of Okhotsk was prepared and published by Stepan Makarov in 1894. The Sea of Okhotsk is rich in biological resources, with various kinds of fish, shellfish and crabs. The harsh conditions of crab fishing in

1827-557: The end of World War II in 1945. Afterward, the Soviet Union occupied the territory. During the Cold War , the Sea of Okhotsk was the scene of several successful U.S. Navy operations (including Operation Ivy Bells ) to tap Soviet Navy undersea communications cables. These operations were documented in the 1998 book Blind Man's Bluff: The Untold Story of American Submarine Espionage . The sea (and surrounding area) were also

1890-422: The family into the subfamilies Arctocephalinae (fur seals) and Otariinae (sea lions) is not supported, with the fur seal Callorhinus ursinus having a basal relationship relative to the rest of the family. This is consistent with the fossil record which suggests that this genus diverged from the line leading to the remaining fur seals and sea lions about 6 million years ago (mya). Similar genetic divergences between

1953-597: The first time, and since then, they have slowly been recolonizing. These sea lions are the only pinnipeds that regularly move up to 2 kilometres (1.2 mi) inland into forests. As consequence, they have been hit by cars on roads, deliberately killed, and been disturbed by dogs. Females need to move inland as a way to protect their pups, so roads, fences, residential areas, and private lands can inhibit their dispersal and breeding success. They have also adapted to commercial pine forests, and have given birth or nursed pups in residents' backyards and on golf courses. As one of

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2016-530: The fleet back to the Sea of Okhotsk. From 1854 to 1856, an average of over 160 vessels cruised in the sea each year. As catches declined between 1858 and 1860 the fleet shifted back to the Bering Strait region. The Russian military marine mammal program reportedly sources some of its animals from the Sea of Okhotsk. South Sakhalin was administered by Japan as Karafuto Prefecture from 1907 to 1949. The Kuril Islands were Japanese from 1855 and 1875 till

2079-521: The formation of sea ice and also drives fish populations north. The salmon catch on the northern Japanese coast has fallen 70% in the last 15 years, while the Russian chum salmon catch has quadrupled. With the exception of Hokkaido , one of the Japanese home islands , the sea is surrounded on all sides by territory administered by the Russian Federation. South Sakhalin and the Kuril Islands were administered by Japan until 1945. Japan claims

2142-450: The fur, generally smaller sizes, farther and longer foraging trips, smaller and more abundant prey items, and greater sexual dimorphism . All sea lions have certain features in common, in particular their coarse, short fur, greater bulk, and larger prey than fur seals. For these reasons, the distinction remains useful. The family Otariidae (Order Carnivora) contains the 15 extant species of fur seals and sea lions. Traditional classification of

2205-491: The increasing water pressure thus forcing the surface air into cartilage lined airway just before the gas exchange surface. This process prevents any further oxygen exchange to the blood for muscles, requiring all muscles to be loaded with enough oxygen to last the duration of the dive. However, this shunt reduces the amount of compressed gases from entering tissues therefore reducing the risk of decompression sickness. The collapse of alveoli does not allow for any oxygen storage in

2268-464: The late Holocene period to the middle of the twentieth century, hunter-gatherers along the Beagle Channel and northern Patagonia had greatly reduced the number of sea lions due to their hunting of the species and exploitation of the species' environment. Although sealing has been put to a halt, in many countries, such as Uruguay , the sea lion population continues to decline because of

2331-534: The legs by large, aggressive males, possibly as territorial acts . In April 2015, a sea lion attacked a 62-year-old man who was boating with his wife in San Diego . The attack left the man with a punctured bone. In May 2017, a sea lion grabbed and pulled a girl into the water by her dress before retreating. The child was sitting on a pier side in British Columbia while tourists were illegally feeding

2394-446: The lungs, however. This means that sea lions must mitigate oxygen use in order to extend their dives. Oxygen availability is prolonged by the physiological control of heart rate in sea lions. By reducing heart rate to well below surface rates, oxygen is saved by reducing gas exchange as well as reducing the energy required for a high heart rate. Bradycardia is a control mechanism to allow a switch from pulmonary oxygen to oxygen stored in

2457-435: The muscles which is needed when the sea lions are diving to depth. Another way sea lions mitigate the oxygen obtained at the surface in dives is to reduce digestion rate. Digestion requires metabolic activity and therefore energy and oxygen are consumed during this process; however, sea lions can limit digestion rate and decrease it by at least 54%. This reduction in digestion results in a proportional reduction in oxygen use in

2520-508: The name of Hokkaidō's Okhotsk Subprefecture , which faces the Sea of Okhotsk and is also known as the Okhotsk region ( オホーツク地方 , Ohōtsuku-chihō ) . Twenty-nine zones of possible oil and gas accumulation have been identified on the Sea of Okhotsk shelf, which runs along the coast. Total reserves are estimated at 3.5 billion tons of equivalent fuel, including 1.2 billion tons of oil and 1.5 billion cubic meters of gas. On 18 December 2011,

2583-465: The necessary steps and began treatment. The treatment seemed to be effective on the pups who have taken it. They found no traces of this infection afterwards. However, the percentage of pups who do have it is still relatively high at about 75%. Those pups who were treated had much better growth rates than those who did not. Overall parasites and hookworms are killing off enough pups to place them in endangerment. Parasites affect sea pups in various areas of

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2646-446: The observations of skulls of several Otariidae species; a general change in size corresponds with a change in latitude and primary productivity. Skulls of Australian sea lions from Western Australia were generally smaller in length whereas the largest skulls are from cool temperate localities. Otariidae are in the process of species divergence, much of which may be driven by local factors, particularly latitude and resources. Populations of

2709-399: The parasites from the early ages of 3 weeks old up until the age of 4 to 8 months. The parasites found in the eye fluke did serious damage to the eye. From the data collected, 21 of the 91 survived; with a total of 70 deaths in just a span of two years. The parasites are attacking the pups at such young ages and causing the pups to not reach the age of reproduction. The death rates of the pups

2772-457: The physiological responses to nutrition, as well as other stressors. In a study done with four Steller sea lions (Eumetopias jubatus), three of the four sea lions underwent a 70-day trial which consisted of unrestricted food intake, acute nutritional stress, and chronic nutritional stress. Results showed that individuals under nutritional stress down-regulated some cellular processes within their immune response and oxidative stress. Nutritional stress

2835-892: The presence of double rooted cheek teeth and is thus thought to represent the most "primitive" line. It was from this basal line that both the sea lions and the remaining fur seal genus, Callorhinus , are thought to have diverged. The fossil record from the western coast of North America presents evidence for the divergence of Callorhinus about 6 mya, whereas fossils in both California and Japan suggest that sea lions did not diverge until years later. There are many components that make up sea lion physiology and these processes control aspects of their behavior. Physiology dictates thermoregulation, osmoregulation, reproduction, metabolic rate, and many other aspects of sea lion ecology including but not limited to their ability to dive to great depths. The sea lions' bodies control heart rate, gas exchange, digestion rate, and blood flow to allow individuals to dive for

2898-417: The resource-defense polygyny, or occupying important female resources. This involves occupying and defending a territory with resources or features attractive to females during sexually receptive periods. Some of these factors may include pupping habitat and access to water. Other techniques include potentially limiting access of other males to females. Otaria flavescens (South American sea lion) lives along

2961-461: The scene of the Soviet attack on Korean Air Lines Flight 007 in 1983. The Soviet Pacific Fleet used the sea as a ballistic missile submarine bastion , a strategy that Russia continues. Despite its proximity to Japan, the Sea of Okhotsk has no native etymology in the Japanese language ; its name, Ohōtsuku-kai ( オホーツク海 ), is a transcription of the Russian name. This is also reflected in

3024-456: The sea lion clades as well as between the major Arctocephalus fur seal clades, suggest that these groups underwent periods of rapid radiation at about the time they diverged from each other. The phylogenetic relationships within the family and the genetic distances among some taxa highlight inconsistencies in the current taxonomic classification of the family. Arctocephalus is characterized by ancestral character states such as dense underfur and

3087-415: The sea lion's food source, which in turn endangers the species. Also, human presence and human recreational activities can cause sea lions to engage in violent and aggressive actions. When humans come closer than 15 meters of a sea lion, the sea lions' vigilance increases because of the disturbance of humans. These disturbances can potentially cause sea lions to have psychological stress responses that cause

3150-411: The sea lions to retreat, sometimes even abandon their locations, and decreases the amount of time sea lions spend hauling out. New Zealand sea lions were also exploited from hunting and sealing, and as a result were extirpated from New Zealand's mainland for over 150 years, with their population being restricted to the subantarctic. In 1993, a female New Zealand sea lion gave birth on the mainland for

3213-545: The sea lions when the incident took place. She was pulled out of the water with minor injuries and received antibiotic prophylactic treatment for seal finger infection from the superficial bite injury. There have also been documented events of sea lions assisting humans. One such notable instance of this is when Kevin Hines jumped off the Golden Gate Bridge in a suicide attempt and was helped to stay afloat by

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3276-535: The sea pups as on the Galapagos Islands, but in addition, the researchers in Australia took blood samples. The pups in Australia were being affected by hookworms, but they were also coming out in large numbers with warmer temperatures. New Zealand sea lion pups ( Phocarctos hookeri ) were also affected in really early ages by hookworms (Uncinaria). The difference is that in New Zealand researchers took

3339-473: The sea temperatures. Cold air from Siberia forms sea ice in the northwestern Sea of Okhotsk. As the ice forms, it expels salt into the deeper layers. This heavy water flows east toward the Pacific, carrying oxygen and nutrients, supporting abundant sea life. The Sea of Okhotsk has warmed in some places by as much as 3°C (5.4°F) since preindustrial times, three times faster than the global mean. Warming inhibits

3402-739: The sea's islands are either in coastal waters or belong to the various islands making up the Kuril Islands chain. These fall either under undisputed Japanese or Russian ownership or disputed ownership between Japan and Russia. Iony Island is the only island located in open waters and belongs to the Khabarovsk Krai of the Russian Federation . The majority of the sea's islands are uninhabited, making them ideal breeding grounds for seals , sea lions , seabirds , and other sea island fauna. Large colonies of crested auklets use

3465-534: The south through the La Pérouse Strait . In winter, navigation on the Sea of Okhotsk is impeded by ice floes . Ice floes form due to the large amount of freshwater from the Amur River , lowering the salinity of upper levels, often raising the freezing point of the sea surface. The distribution and thickness of ice floes depends on many factors: the location, the time of year, water currents, and

3528-522: The southern Kuril Islands and refers to them as Northern Territories . The International Hydrographic Organization defines the limits of the Sea of Okhotsk as follows: :: On the Southwest. The Northeastern and Northern limits on the Japan Sea [In La Perouse Strait (Sôya Kaikyô). A line joining Sôni Misaki and Nishi Notoro Misaki (45°55'N). From Cape Tuik (51°45'N) to Cape Sushcheva]. :: On

3591-408: The stomach and therefore a correlated oxygen supply for diving. Digestion rate in these sea lions increases back to normal rates immediately upon resurfacing. Oxygen depletion limits dive duration, but carbon dioxide (CO 2 ) build-up also plays a role in the dive capabilities of many marine mammals . After a sea lion returns from a long dive, CO 2 is not expired as fast as oxygen is replenished in

3654-546: The subfamily Arcocephalinae. This division was based on the most prominent common feature shared by the fur seals and absent in the sea lions, namely the dense underfur characteristic of the former. Recent genetic evidence, suggests Callorhinus , the genus of the northern fur seal , is more closely related to some sea lion species than to the other fur seal genus, Arctocephalus . Therefore, the fur seal/sea lion subfamily distinction has been eliminated from many taxonomies. Nonetheless, all fur seals have certain features in common:

3717-446: The survival of juveniles. The disease appears to be compounded by global warming. The number of infectious stages of different parasites species has a strong correlation with temperature change, therefore it is essential to consider the correlation between the increasing number of parasitic infections and climate changes. The Galapagos Islands go through seasonal changes in sea surface temperatures , which consist of high temperatures from

3780-486: The world's rarest sea lions, and an endangered and endemic species, efforts are being made to facilitate coexistence between them and humans. Sea lion attacks on humans are rare, but when humans come within approximately 2.5 meters (8 ft), it can be very unsafe. In a highly unusual attack in 2007 in Western Australia , a sea lion leapt from the water and seriously mauled a 13-year-old girl surfing behind

3843-417: The world. Reproductive success reduces immensely, survival methods, changes in health and growth have also been affected. Similarly, climate change has resulted in increased toxic algae blooms in the oceans. These toxins are ingested by sardines and other fish which are then eaten by the sea lions, causing neurological damage and diseases such as epilepsy. Gene expressions are being used more often to detect

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3906-505: The year consist of a mix of ages and genders in the rookeries with haul-out patterns varying monthly. Steller sea lions, living an average of 15 to 20 years, begin their breeding season when adult males establish territories along the rookeries in early May. Male sea lions reach sexual maturity from ages 5 to 7 and do not become territorial until around 9 to 13 years of age. The females arrive in late May bringing in an increase of territorial defense through fighting and boundary displays. After

3969-682: Was considered the most proximate cause of population decline in this species. In New Zealand sea lions, north-to south gradients driven by temperature differences were shown to be key factors in the prey mix. Adult California sea lions eat about 5% to 8% of their body weight per day (15–40 lb (6.8–18.1 kg)). California sea lions feed mainly offshore in coastal areas. They eat a variety of prey—such as squid, anchovies, mackerel, rockfish, and sardines—found in upwelling areas. They also may take fish from commercial fishing gear, sport fishing lines, and fish passage facilities at dams and rivers. Geographic variation for sea lions have been determined by

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