Post by DinosaurMichael on Aug 22, 2013 17:43:03 GMT 5
Walrus - Odobenus rosmarus
The walrus (Odobenus rosmarus) 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) which lives in the Atlantic Ocean, the Pacific walrus (O. rosmarus divergens) which lives in the Pacific Ocean, and O. rosmarus laptevi, which lives in the Laptev Sea. The walrus is easily recognized by its prominent tusks, whiskers and great bulk. Adult Pacific males can weigh more than 1,700 kilograms (3,700 lb) and, among pinnipeds, are exceeded in size only by the two species of elephant seals. It resides primarily in shallow oceanic shelf habitat, spending a significant proportion of its life on sea ice in pursuit of its preferred diet of benthic bivalve mollusks. It is a relatively long-lived, social animal and is considered a keystone species in Arctic marine ecosystems. The walrus has played a prominent role in the cultures of many indigenous Arctic peoples, who have hunted the walrus for its meat, fat, skin, tusks and bone. In the 19th and early 20th centuries, the walrus was the object of heavy commercial exploitation for blubber and ivory and its numbers declined rapidly. Its global population has since rebounded, though the Atlantic and Laptev populations remain fragmented and at historically depressed levels. While some outsized Pacific males can weigh as much as 2,000 kg (4,400 lb), most weigh between 800 and 1,680 kg (1,800 and 3,700 lb). The Atlantic subspecies weighs about 10–20% less than the Pacific subspecies. The Atlantic Walrus also tends to have relatively shorter tusks and somewhat more flattened snout. Females weigh about two-thirds as much, with the Atlantic females averaging 560 kg (1,200 lb), sometimes weighing as little as 400 kg (880 lbs), and the Pacific female averaging 794 kg (1,750 lb). Length ranges from 2.2 to 3.6 m (7.2–12 ft). It is the second largest pinniped, after the elephant seals. The walrus' body shape shares features with both sea lions (eared seals: Otariidae) and seals (true seals: Phocidae). As with otariids, it can turn its rear flippers forward and move on all fours; however, its swimming technique is more like that of true seals, relying less on flippers and more on sinuous whole body movements. Also like phocids, it lacks external ears.
Saltwater Crocodile - Crocodylus porosus
The saltwater crocodile, also known as estuarine or Indo-Pacific crocodile, (Crocodylus porosus) is the largest of all living reptiles. It is found in suitable habitats in Northern Australia, the eastern coast of India and parts of Southeast Asia. The saltwater crocodile has a longer muzzle than the mugger crocodile: its length is twice its breadth at the base. The saltwater crocodile has fewer armor plates on its neck than other crocodilians, and its broad body contrasts with that of most other lean crocodiles, leading to early unverified assumptions that the reptile was an alligator. Saltwater crocodile skull from The Museum of Zoology, Saint PetersburgNewly hatched saltwater crocodiles measure about 25 to 30 centimetres (9.8–12 in) long and weigh an average of 70 grams (2.5 oz). Males reach sexual maturity at around 3.3 metres (11 ft) at around 16 years of age, while females reach sexual maturity at 2.1 metres (6.9 ft) and 12–14 years. An adult male saltwater crocodile's weight is 409 to 1,000 kilograms (900–2,200 lb) and length is normally 4.1 to 5.5 metres (13–18 ft). However, mature males can exceed 6 metres (20 ft) and weigh more than 1,000 kilograms (2,200 lb) and this species is the only extant crocodilian to regularly reach or exceed 4.8 metres (16 ft). Weight can vary enormously based upon condition and age, older males tending to outweigh younger ones since they maintain prime territories with access to better, more abundant prey. For example, crocodiles at 4.8 metres (16 ft) long have ranged in mass variously from 522 kilograms (1,150 lb) to 1,000 kilograms (2,200 lb). This species has the greatest sexual dimorphism of any modern crocodilian, with females being much smaller than males. Typical female body lengths in the range of 2.3 to 3.5 metres (8–11 ft). The largest female on record measured about 4.2 metres (14 ft). The mean weight of the species as a whole is roughly 450 kilograms (1,000 lb). Saltwater crocodile outside Cairns, QueenslandThe largest size saltwater crocodiles can reach is the subject of considerable controversy. The longest crocodile ever measured snout-to-tail and verified was the skin of a dead crocodile, which was 6.2 metres (20 ft) long. As skins tend to shrink slightly after removal from the carcass, this crocodile's living length was estimated at 6.3 metres (21 ft), and it could have weighed more than 1,000 kilograms (2,200 lb). Incomplete remains (the skull of a crocodile shot in Orissa)[ have been claimed to come from a 7.6-metre (25 ft) crocodile, but scholarly examination suggested a length no greater than 7 metres (23 ft). There have been numerous claims of crocodiles in the 9-metre (30 ft) range: the crocodile shot in the Bay of Bengal in 1840, reported at 10 metres (33 ft); another killed in 1823 at Jalajala on the main island of Luzon in the Philippines reported at 8.2 metres (27 ft); a reported 7.6 metres (25 ft) crocodile killed in the Hooghly River in the Alipore District of Calcutta. However, examinations of these animals' skulls actually indicated animals ranging from 6 to 6.6 metres (20–21.7 ft). A crocodile shot in Queensland in 1957 was reported to be 8.63 metres (28.3 ft) long, but no verified measurements were made and no remains of this crocodile exist. A "replica" of this crocodile has been made as a tourist attraction. Many other unconfirmed reports of crocodiles exceeding 8 metres (28+ ft) have been made but these are highly unlikely. With recent restoration of saltwater crocodile habitat and reduced poaching, it is possible that 7-metre (23 ft) crocodiles are alive today. Guinness has accepted a claim of a 7-metre (23 ft), 2,000 kg (4,400 lb) male saltwater crocodile living within Bhitarkanika Park in the state of Orissa, India, although, due to the difficulty of trapping and measuring a very large live crocodile, the accuracy of these dimensions has yet to be verified.
The walrus (Odobenus rosmarus) 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) which lives in the Atlantic Ocean, the Pacific walrus (O. rosmarus divergens) which lives in the Pacific Ocean, and O. rosmarus laptevi, which lives in the Laptev Sea. The walrus is easily recognized by its prominent tusks, whiskers and great bulk. Adult Pacific males can weigh more than 1,700 kilograms (3,700 lb) and, among pinnipeds, are exceeded in size only by the two species of elephant seals. It resides primarily in shallow oceanic shelf habitat, spending a significant proportion of its life on sea ice in pursuit of its preferred diet of benthic bivalve mollusks. It is a relatively long-lived, social animal and is considered a keystone species in Arctic marine ecosystems. The walrus has played a prominent role in the cultures of many indigenous Arctic peoples, who have hunted the walrus for its meat, fat, skin, tusks and bone. In the 19th and early 20th centuries, the walrus was the object of heavy commercial exploitation for blubber and ivory and its numbers declined rapidly. Its global population has since rebounded, though the Atlantic and Laptev populations remain fragmented and at historically depressed levels. While some outsized Pacific males can weigh as much as 2,000 kg (4,400 lb), most weigh between 800 and 1,680 kg (1,800 and 3,700 lb). The Atlantic subspecies weighs about 10–20% less than the Pacific subspecies. The Atlantic Walrus also tends to have relatively shorter tusks and somewhat more flattened snout. Females weigh about two-thirds as much, with the Atlantic females averaging 560 kg (1,200 lb), sometimes weighing as little as 400 kg (880 lbs), and the Pacific female averaging 794 kg (1,750 lb). Length ranges from 2.2 to 3.6 m (7.2–12 ft). It is the second largest pinniped, after the elephant seals. The walrus' body shape shares features with both sea lions (eared seals: Otariidae) and seals (true seals: Phocidae). As with otariids, it can turn its rear flippers forward and move on all fours; however, its swimming technique is more like that of true seals, relying less on flippers and more on sinuous whole body movements. Also like phocids, it lacks external ears.
Saltwater Crocodile - Crocodylus porosus
The saltwater crocodile, also known as estuarine or Indo-Pacific crocodile, (Crocodylus porosus) is the largest of all living reptiles. It is found in suitable habitats in Northern Australia, the eastern coast of India and parts of Southeast Asia. The saltwater crocodile has a longer muzzle than the mugger crocodile: its length is twice its breadth at the base. The saltwater crocodile has fewer armor plates on its neck than other crocodilians, and its broad body contrasts with that of most other lean crocodiles, leading to early unverified assumptions that the reptile was an alligator. Saltwater crocodile skull from The Museum of Zoology, Saint PetersburgNewly hatched saltwater crocodiles measure about 25 to 30 centimetres (9.8–12 in) long and weigh an average of 70 grams (2.5 oz). Males reach sexual maturity at around 3.3 metres (11 ft) at around 16 years of age, while females reach sexual maturity at 2.1 metres (6.9 ft) and 12–14 years. An adult male saltwater crocodile's weight is 409 to 1,000 kilograms (900–2,200 lb) and length is normally 4.1 to 5.5 metres (13–18 ft). However, mature males can exceed 6 metres (20 ft) and weigh more than 1,000 kilograms (2,200 lb) and this species is the only extant crocodilian to regularly reach or exceed 4.8 metres (16 ft). Weight can vary enormously based upon condition and age, older males tending to outweigh younger ones since they maintain prime territories with access to better, more abundant prey. For example, crocodiles at 4.8 metres (16 ft) long have ranged in mass variously from 522 kilograms (1,150 lb) to 1,000 kilograms (2,200 lb). This species has the greatest sexual dimorphism of any modern crocodilian, with females being much smaller than males. Typical female body lengths in the range of 2.3 to 3.5 metres (8–11 ft). The largest female on record measured about 4.2 metres (14 ft). The mean weight of the species as a whole is roughly 450 kilograms (1,000 lb). Saltwater crocodile outside Cairns, QueenslandThe largest size saltwater crocodiles can reach is the subject of considerable controversy. The longest crocodile ever measured snout-to-tail and verified was the skin of a dead crocodile, which was 6.2 metres (20 ft) long. As skins tend to shrink slightly after removal from the carcass, this crocodile's living length was estimated at 6.3 metres (21 ft), and it could have weighed more than 1,000 kilograms (2,200 lb). Incomplete remains (the skull of a crocodile shot in Orissa)[ have been claimed to come from a 7.6-metre (25 ft) crocodile, but scholarly examination suggested a length no greater than 7 metres (23 ft). There have been numerous claims of crocodiles in the 9-metre (30 ft) range: the crocodile shot in the Bay of Bengal in 1840, reported at 10 metres (33 ft); another killed in 1823 at Jalajala on the main island of Luzon in the Philippines reported at 8.2 metres (27 ft); a reported 7.6 metres (25 ft) crocodile killed in the Hooghly River in the Alipore District of Calcutta. However, examinations of these animals' skulls actually indicated animals ranging from 6 to 6.6 metres (20–21.7 ft). A crocodile shot in Queensland in 1957 was reported to be 8.63 metres (28.3 ft) long, but no verified measurements were made and no remains of this crocodile exist. A "replica" of this crocodile has been made as a tourist attraction. Many other unconfirmed reports of crocodiles exceeding 8 metres (28+ ft) have been made but these are highly unlikely. With recent restoration of saltwater crocodile habitat and reduced poaching, it is possible that 7-metre (23 ft) crocodiles are alive today. Guinness has accepted a claim of a 7-metre (23 ft), 2,000 kg (4,400 lb) male saltwater crocodile living within Bhitarkanika Park in the state of Orissa, India, although, due to the difficulty of trapping and measuring a very large live crocodile, the accuracy of these dimensions has yet to be verified.
