The southern elephant seal (Mirounga leonina) is one of the two species of elephant seals. It is the largest member of the clade Pinnipedia and the order Carnivora, as well as the largest extant marine mammal that is not a cetacean. It gets its name from its massive size and the large proboscis of the adult male, which is used to produce very loud roars, especially during the breeding season. A bull southern elephant seal is about 40% heavier than a male northern elephant seal (Mirounga angustirostris), more than twice as heavy as a male walrus (Odobenus rosmarus), and six to seven times heavier than the largest living terrestrial carnivorans, the polar bear (Ursus maritimus) and the Kodiak bear (Ursus arctos middendorffi).
|Southern elephant seal|
|Females and pups|
|Southern elephant seal range|
Phoca leonina Linnaeus, 1758
The southern elephant seal was one of the many species originally described by Swedish zoologist Carl Linnaeus in the landmark 1758 10th edition of his Systema Naturae, where it was given the binomial name of Phoca leonina. John Edward Gray established the genus Mirounga in 1827.
In the nineteenth century the species was often called "bottle-nosed seal".
The southern elephant seal is distinguished from the northern elephant seal (which does not overlap in range with this species) by its greater body mass and a shorter proboscis. The southern males also appear taller when fighting, due to their tendency to bend their backs more strongly than the northern species. This seal shows extreme sexual dimorphism in size, seemingly the largest of any mammal by mass ratio, with the males typically five to six times heavier than the females. In comparison, in two other very large marine mammals with high size sexual dimorphism, the northern elephant seal and the sperm whale (Physeter macrocephalus), the males weigh on average about three times as much as the females, and only more than four times as heavy in exceptionally heavy bull specimens. While the female southern elephant seal typically weighs 400 to 900 kg (880 to 1,980 lb) and measures 2.6 to 3 m (8.5 to 9.8 ft) long, the bulls typically weigh 2,200 to 4,000 kg (4,900 to 8,800 lb) and measure from 4.2 to 5.8 m (14 to 19 ft) long. An adult female averages 771 kg (1,700 lb) in mass, while a mature bull averages about 3,175 kg (7,000 lb). Studies have indicated elephant seals from South Georgia are around 30% heavier and 10% longer on average than those from Macquarie Island. The record-sized bull, shot in Possession Bay, South Georgia, on 28 February 1913, measured 6.85 m (22.5 ft) long and was estimated to weigh a hulking 5,000 kg (11,000 lb), although it was only partially weighed piecemeal. The maximum size of a female is 1,000 kg (2,200 lb) and 3.7 m (12 ft). The eyes are large, round, and black. The width of the eyes, and a high concentration of low-light pigments, suggest sight plays an important role in the capture of prey. Like all seals, elephant seals have hind limbs whose ends form the tail and tail fin. Each of the "feet" can deploy five long, webbed fingers. This agile dual palm is used to propel water. The pectoral fins are used little while swimming. While their hind limbs are unfit for locomotion on land, elephant seals use their fins as support to propel their bodies. They are able to propel themselves quickly (as fast as 8 km/h (5.0 mph)) in this way for short-distance travel, to return to water, to catch up with a female, or to chase an intruder.
Pups are born with fur and are completely black. Their coats are unsuited to water, but protect infants by insulating them from the cold air. The first moulting accompanies weaning. After moulting, the coats may turn grey and brown, depending on the thickness and moisture of hair. Among older males, the skin takes the form of a thick leather which is often scarred.
Like other seals, the vascular system of elephant seals is adapted to the cold; a mixture of small veins surround arteries, capturing heat from them. This structure is present in extremities such as the hind legs.
The world population was estimated at 650,000 animals in the mid-1990s, and was estimated in 2005 at between 664,000 and 740,000 animals. Studies have shown the existence of three geographic subpopulations, one in each of the three oceans.
Tracking studies have indicated the routes traveled by elephant seals, demonstrating their main feeding area is at the edge of the Antarctic continent. While elephant seals may come ashore in Antarctica occasionally to rest or to mate, they gather to breed in subantarctic locations.
The largest subpopulation is in the South Atlantic, with more than 400,000 individuals, including about 113,000 breeding females on South Georgia; the other breeding colonies of the Atlantic subpopulation are located on the Falkland Islands and Valdes Peninsula in Argentina (the only continental breeding population).
The second subpopulation, in the south Indian Ocean, consist of up to 200,000 individuals, three-quarters of which breed in the Kerguelen Islands and the rest in the Crozet Islands, Marion and Prince Edward Islands, and Heard Island. Some individuals also breed on Amsterdam Island.
Colonies once existed in Tasmania, Saint Helena, and the Juan Fernández Islands off the coast of Chile. Some individuals at the time of moulting have been found in South Africa or Australia. Lost animals have also been reported from time to time on the shores of Mauritius, with two reports from the Río Guayas estuary area in Ecuador. Reality of the creature so called Manatee of Helena had been pointed out as possible misidentification of elephant seals historically present on Saint Helena.
After the end of large-scale seal hunting in the 19th century, the southern elephant seal recovered to a sizable population in the 1950s; since then, an unexplained decline in the subpopulations of the Indian Ocean and Pacific Ocean has occurred. The population now seems to be stable; the reasons for the fluctuation are unknown. Suggested explanations include a phenomenon of depression following a rapid demographic rebound that depletes vital resources, a change in climate, competition with other species whose numbers also varied, or even an adverse influence of scientific monitoring techniques.
Elephant seals are among the seals that can stay on land for the longest periods of time, as they can stay dry for several consecutive weeks each year. Males arrive in the colonies earlier than the females and fight for control of harems when they arrive. Large body size confers advantages in fighting and the agonistic relationships of the bulls gives rise to a dominance hierarchy, with access to harems and activity within harems being determined by rank. The dominant bulls (“harem masters”) establish harems of several dozen females. The least successful males have no harems, but may try to copulate with a harem male's females when the male is not looking. The majority of primiparous females and a significant proportion of multiparous females mate at sea with roaming males away from harems.
An elephant seal must stay in his territory to defend it, which could mean months without eating, having to live on his blubber storage. Two fighting males use their weight and canine teeth against each other. The outcome is rarely fatal, and the defeated bull will flee; however, bulls can suffer severe tears and cuts. Some males can stay ashore for more than three months without food. Males commonly vocalize with a coughing roar that serves in both individual recognition and size assessment. Conflicts between high-ranking males are more often resolved with posturing and vocalizing than with physical contact.
Generally, pups are born rather quickly in the breeding season. After being born, a newborn will bark or yap and its mother will respond with a high-pitched moan. The newborn begins to suckle immediately. Lactation lasts an average of 23 days. Throughout this period, the female fasts. Newborns weigh about 40 kg (88 lb) at birth, and reach 120 to 130 kg (260 to 290 lb) by the time they are weaned. The mother loses significant weight during this time. Young weaned seals gather in nurseries until they lose their birth coats. They enter the water to practice swimming, generally starting their apprenticeship in estuaries or ponds. In summer, the elephant seals come ashore to moult. This sometimes happens directly after reproduction.
Satellite tracking revealed the seals spend very little time on the surface, usually a few minutes for breathing. They dive repeatedly, each time for more than 20 minutes, to hunt their prey—squid and fish—at depths of 400 to 1,000 m (1,300 to 3,300 ft). They are the deepest diving air-breathing non-cetaceans and have been recorded at a maximum of 2,133 m (6,998 ft) in depth.
As far as duration, depth, and the sequence of dives, the southern elephant seal is the best performing seal. In many regards, they exceed even most cetaceans. These capabilities result from nonstandard physiological adaptations, common to marine mammals, but particularly developed in elephant seals. The coping strategy is based on increased oxygen storage and reduced oxygen consumption.
In the ocean, the seals apparently live alone. Most females dive in pelagic zones for foraging, while males dive in both pelagic and benthic zones. Individuals will return annually to the same hunting areas. Due to the inaccessibility of their deep-water foraging areas, no comprehensive information has been obtained about their dietary preferences, although some observation of hunting behavior and prey selection has occurred.
While hunting in the dark depths, elephant seals seem to locate their prey, at least in part, using vision; the bioluminescence of some prey animals can facilitate their capture. Elephant seals do not have a developed system of echolocation in the manner of cetaceans, but their vibrissae (facial whiskers), which are sensitive to vibrations, are assumed to play a role in search of food. When at the subantarctic or Antarctic coasts, the seals can also consume molluscs, crustaceans, nothothens, lanternfish, krill, cephalopods or even algae.
Weaned pups, juveniles and even adults of up to adult male size may fall prey to orcas. Cases where weaned pups have been attacked and killed by leopard seals (Hydrurga leptonyx) and New Zealand sea lions (Phocarctos hookeri), exclusively small pups in the latter case, have been recorded. Great white sharks (Carcharodon carcharias) have hunted elephant seals near Campbell Island, while bite marks from a southern sleeper shark (Somniosus antarcticus) have been found on surviving elephant seals in the Macquarie Islands.
After their near extinction due to hunting in the 19th century, the total population was estimated at between 664,000 and 740,000 animals in 2005, but as of 2002, two of the three major populations were declining. The reasons for this are unclear, but are thought to be related to the distribution and declining levels of the seals' primary food sources. Most of their most important breeding sites are now protected by international treaty, as UNESCO World Heritage Sites, or by national legislation.
One of the most famous southern elephant seals is Minazo, who lived in Japan's Enoshima Aquarium from when he was a half-year old until his death in 2005 at age 11. Minazo became popular for his signature bucket-holding, tongue-lolling pose. In 2006, Minazo was memorialized by the Japanese noise musician Masami Akita, also known as Merzbow, in a two-volume album, with artwork by Jenny Akita showing Minazo holding his beloved bucket.
In 2007, Minazo became the subject of an image macro similar to lolcat called "lolrus". In his liner notes, Masami Akita suggested Minazo's frequent and demanding performances left him exhausted, contributing ultimately to his death. Akita's intention in celebrating Minazo was to highlight the plight of captive animals used for performance before public audiences. Minazo has also been featured on several T-shirt designs.
In biology and immunology, an Alphavirus belongs to group IV of the Baltimore classification of the Togaviridae family of viruses, according to the system of classification based on viral genome composition introduced by David Baltimore in 1971. Alphaviruses, like all other group IV viruses, have a positive sense, single-stranded RNA genome. There are thirty alphaviruses able to infect various vertebrates such as humans, rodents, fish, birds, and larger mammals such as horses as well as invertebrates. Transmission between species and individuals occurs mainly via mosquitoes, making the alphaviruses a member of the collection of arboviruses – or arthropod-borne viruses. Alphavirus particles are enveloped, have a 70 nm diameter, tend to be spherical (although slightly pleomorphic), and have a 40 nm isometric nucleocapsid.Carnivora
Carnivora (; from Latin carō (stem carn-) "flesh" and vorāre "to devour") is a diverse scrotiferan order that includes over 280 species of placental mammals. Its members are formally referred to as carnivorans, whereas the word "carnivore" (often popularly applied to members of this group) can refer to any meat-eating organism. Carnivorans are the most diverse in size of any mammalian order, ranging from the least weasel (Mustela nivalis), at as little as 25 g (0.88 oz) and 11 cm (4.3 in), to the polar bear (Ursus maritimus), which can weigh up to 1,000 kg (2,200 lb), to the southern elephant seal (Mirounga leonina), whose adult males weigh up to 5,000 kg (11,000 lb) and measure up to 6.7 m (22 ft) in length.
Carnivorans have teeth and claws adapted for catching and eating other animals. Many hunt in packs and are social animals, giving them an advantage over larger prey. Some carnivorans, such as cats and pinnipeds, depend entirely on meat for their nutrition. Others, such as raccoons and bears, are more omnivorous, depending on the habitat. The giant panda is largely a herbivore, but also feeds on fish, eggs and insects. The polar bear subsists mainly on seals.
Carnivorans are split into two suborders: Feliformia ("catlike") and Caniformia ("doglike").Earless seal
The earless seals, phocids or true seals are one of the three main groups of mammals within the seal lineage, Pinnipedia. All true seals are members of the family Phocidae . They are sometimes called crawling seals to distinguish them from the fur seals and sea lions of the family Otariidae. Seals live in the oceans of both hemispheres and, with the exception of the more tropical monk seals, are mostly confined to polar, subpolar, and temperate climates. The Baikal seal is the only species of exclusively freshwater seal.Elephant seal
Elephant seals are large, oceangoing earless seals in the genus Mirounga. The two species, the northern elephant seal (M. angustirostris) and the southern elephant seal (M. leonina), were both hunted to the brink of extinction by the end of the 19th century, but the numbers have since recovered.
The northern elephant seal, somewhat smaller than its southern relative, ranges over the Pacific coast of the U.S., Canada and Mexico. The most northerly breeding location on the Pacific Coast is at Race Rocks, at the southern tip of Vancouver Island in the Strait of Juan de Fuca. The southern elephant seal is found in the Southern Hemisphere on islands such as South Georgia and Macquarie Island, and on the coasts of New Zealand, South Africa, and Argentina in the Peninsula Valdés. In southern Chile, there is a small colony of 120 animals at Jackson Bay, Admiralty Sound (Seno Almirantazgo), Tierra del Fuego. The oldest known unambiguous elephant seal fossils are fragmentary fossils of an unnamed member of the tribe Miroungini described from the late Pliocene Petane Formation of New Zealand. Teeth originally identified as representing an unnamed species of Mirounga have been found in South Africa, and dated to the Miocene epoch; however Boessenecker & Churchill (2016) considered these teeth to be almost certainly misidentified odontocete teeth.Elephant seals breed annually and are seemingly faithful to colonies that have established breeding areas.Facklamia miroungae
Facklamia miroungae is a Gram-positive and facultatively anaerobic bacteria from the family of Facklamia which has been isolated from the nasal cavity of a southern elephant seal (Mirounga leonina).Jeotgalicoccus pinnipedialis
Jeotgalicoccus pinnipedialis is a gram-positive bacterium. It belongs to the Staphylococcaceae. The cells are coccoid. It was found in the swab of the mouth of a Southern elephant seal.Lake Moeraki
Lake Moeraki is a small lake on the Moeraki River on the West Coast of the South Island of New Zealand. State Highway 6 runs along its western edge.
The lake is surrounded by native vegetation and lies within the Te Wahipounamu World Heritage site.
Tours to watch Fiordland crested penguins are popular attractions for tourists. Since 1989, A bull southern elephant seal, named "Humphrey" returns annually . This species is rather rare on New Zealand coasts. Another individual sometimes migrate here as well. Occasionally, other pinnipeds such as New Zealand fur seals and sea lions visit around. Hector's dolphins may possibly swim along the shores.Leopard seal
The leopard seal (Hydrurga leptonyx), also referred to as the sea leopard, is the second largest species of seal in the Antarctic (after the southern elephant seal). Its only natural predators are the killer whale. It feeds on a wide range of prey including cephalopods, other pinnipeds, krill, birds and fish. It is the only species in the genus Hydrurga. Its closest relatives are the Ross seal, the crabeater seal and the Weddell seal, which together are known as the tribe of lobodontini seals. The name hydrurga means "water worker" and leptonyx is the Greek for "small clawed".List of mammals of New Zealand
This is a list of the native living mammals of New Zealand. It does not include introduced species, nor extinct Saint Bathans Fauna.M. leonina
M. leonina may refer to:
Macaca leonina, the northern pig-tailed macaque, a primate species
Melibe leonina, the hooded nudibranch or the lion nudibranch, a predatory sea slug species
Mirounga leonina, the southern elephant seal, an elephant seal speciesMinazo Vol. 1
Minazo Vol. 1 (美男象, Minazō) is an album by Japanese noise musician Merzbow. It was followed by Minazo Volume Two released on vinyl.
The album is dedicated to Minazo, who was the only male southern elephant seal in Japan. Minazo was brought from Uruguay in 1995, and was kept at Enoshima Aquarium until his death on October 4, 2005. He was 11 years old; the average life expectancy of an elephant seal is 20 years. In the liner notes, Masami Akita writes that Minazo was made to perform tricks at mealtime, which Akita speculates left him exhausted and may have led to his early death. Akita also laments that many of the aquariums in Japan are mere amusement establishments, and hopes that they will eventually end the exhibition of animals and only function as shelters.Minazo was depicted on the cover of Merzbeat.Minazo Volume Two
Minazo Volume Two is an album by the Japanese noise musician Merzbow. It is dedicated to Minazo, who was the only male southern elephant seal in Japan. It follows Minazo Vol. 1 released on CD.Northern elephant seal
The northern elephant seal (Mirounga angustirostris) is one of two species of elephant seal (the other is the southern elephant seal). It is a member of the family Phocidae (true seals). Elephant seals derive their name from their great size and from the male's large proboscis, which is used in making extraordinarily loud roaring noises, especially during the mating competition. Sexual dimorphism in size is great. Correspondingly, the mating system is highly polygynous; a successful male is able to impregnate up to 50 females in one season.Pinniped
Pinnipeds, commonly known as seals, are a widely distributed and diverse clade of carnivorous, fin-footed, semiaquatic marine mammals. They comprise the extant families Odobenidae (whose only living member is the walrus), Otariidae (the eared seals: sea lions and fur seals), and Phocidae (the earless seals, or true seals). There are 33 extant species of pinnipeds, and more than 50 extinct species have been described from fossils. While seals were historically thought to have descended from two ancestral lines, molecular evidence supports them as a monophyletic lineage (descended from one ancestral line). Pinnipeds belong to the order Carnivora and their closest living relatives are believed to be bears and the superfamily of musteloids (weasels, raccoons, skunks, and red pandas), having diverged about 50 million years ago.
Seals range in size from the 1 m (3 ft 3 in) and 45 kg (99 lb) Baikal seal to the 5 m (16 ft) and 3,200 kg (7,100 lb) southern elephant seal, which is also the largest member of the order Carnivora. Several species exhibit sexual dimorphism. They have streamlined bodies and four limbs that are modified into flippers. Though not as fast in the water as dolphins, seals are more flexible and agile. Otariids use their front limbs primarily to propel themselves through the water, while phocids and walruses use their hind limbs. Otariids and walruses have hind limbs that can be pulled under the body and used as legs on land. By comparison, terrestrial locomotion by phocids is more cumbersome. Otariids have visible external ears, while phocids and walruses lack these. Pinnipeds have well-developed senses—their eyesight and hearing are adapted for both air and water, and they have an advanced tactile system in their whiskers or vibrissae. Some species are well adapted for diving to great depths. They have a layer of fat, or blubber, under the skin to keep warm in the cold water, and, other than the walrus, all species are covered in fur.
Although pinnipeds are widespread, most species prefer the colder waters of the Northern and Southern Hemispheres. They spend most of their lives in the water, but come ashore to mate, give birth, molt or escape from predators, such as sharks and killer whales. They feed largely on fish and marine invertebrates; but a few, like the leopard seal, feed on large vertebrates, such as penguins and other seals. Walruses are specialized for feeding on bottom-dwelling mollusks. Male pinnipeds typically mate with more than one female (polygyny), although the degree of polygyny varies with the species. The males of land-breeding species tend to mate with a greater number of females than those of ice breeding species. Male pinniped strategies for reproductive success vary between defending females, defending territories that attract females and performing ritual displays or lek mating. Pups are typically born in the spring and summer months and females bear almost all the responsibility for raising them. Mothers of some species fast and nurse their young for a relatively short period of time while others take foraging trips at sea between nursing bouts. Walruses are known to nurse their young while at sea. Seals produce a number of vocalizations, notably the barks of California sea lions, the gong-like calls of walruses and the complex songs of Weddell seals.
The meat, blubber and fur coats of pinnipeds have traditionally been used by indigenous peoples of the Arctic. Seals have been depicted in various cultures worldwide. They are commonly kept in captivity and are even sometimes trained to perform tricks and tasks. Once relentlessly hunted by commercial industries for their products, seals and walruses are now protected by international law. The Japanese sea lion and the Caribbean monk seal have become extinct in the past century, while the Mediterranean monk seal and Hawaiian monk seal are ranked endangered by the International Union for Conservation of Nature. Besides hunting, pinnipeds also face threats from accidental trapping, marine pollution, and conflicts with local people.Seal Island (Shoalwater, Western Australia)
Seal Island (32°17′36″S 115°41′19″E) is located near Shoalwater, Western Australia in the Perth region. In December 2016, a rare birth of a southern elephant seal pup on the island was just the third such event recorded in Western Australia in 20 years and only the tenth in Australia since 1958.Southern Indian Ocean Islands tundra
The Southern Indian Ocean Islands tundra is a tundra ecoregion that includes several subantarctic islands in the southern Indian Ocean.
Extant Carnivora species