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More About Seals and Sea Lions ...
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Pinnipeds are large marine mammals belonging to the Pinnipedia, a suborder of the order Carnivora. The true seals, sea lions, fur seals and Walrus are all pinnipeds.
Pinnipeds are typically sleek bodied and rather large. The smallest pinniped, the Galapagos Fur Seal weighs about 30 kg when full-grown and is 1.2 metres long; the largest, the male Southern Elephant Seal, is over 4 metres long and weighs up to 2,200 kg. All are carnivorous and live on fish, shellfish, squid, and other marine creatures.
It has long been believed that the pinnipeds are descended from a land-based carnivore, something approximately like a dog that has undergone aquatic adaptation. During the 20th Century there was considerable debate about the relationship between them; some taxonomists maintaining the traditional view that they share a common ancestor, others suggesting that the eared seals (sea lions and fur seals) are distinct from the true seals, and that the similarities between the two groups are the result of convergent evolution. If this were so, Pinnipedia would be a paraphyletic grouping with no taxonomic meaning. Recent studies of mitochondrial DNA, however, have strongly supported the monophyletic hypothesis: that is, the evidence is currently on the side of a single-ancestor theory.
The true seals or earless seals are one of the three main groups of mammals within the seal suborder, 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 family Otariidae.
Phocids are the more highly specialized for aquatic life of the two groups and, unlike otariids, lack external ears and cannot bring their hind flippers under their body to walk on them.
They are more streamlined than fur seals and sea lions, and can therefore swim more effectively over long distances than otariids. However, because they cannot turn their hind flippers downward, they are very clumsy on land because they have to wriggle with their front flippers and abdominal muscles; this method of locomotion is called gallumphing.
While otariids are built for speed and maneuverability in the water, phocids are built for efficient, economical movement. This allows most phocids to make long foraging trips to exploit prey resources that are far from land, whereas otariids are tied to rich upwelling zones close to their breeding sites. The phocid reproductive cycle is characterized by temporal and spatial separation between feeding and maternal investment; in other words, a pregnant female spends a long period of time foraging at sea, building up her fat reserves, and then returns to the breeding site and uses her stored energy reserves to provide milk for her pup. (It should be noted that the common seal (harbor seal in the U.S.), Phoca vitulina, does not separate foraging and maternal investment; instead, it displays a reproductive strategy similar to those of otariids, in which the mother makes short foraging trips between nursing bouts.)
Because the pup receives the milk energy from its mother so quickly, its development is typically not complete enough for it to begin foraging on its own as soon as the nursing period is complete. Seals, like all marine mammals, need time to develop the oxygen stores, swimming muscles and neural pathways necessary for effective diving and foraging. Because of this, most phocids undergo a postweaning fast, in which they remain on or near the breeding site and live off of the fat stores they acquired from their mothers until they are ready to begin foraging on their own. These pups typically eat no food and drink no water during the fast, although some polar species have been observed to eat snow. The postweaning fast ranges from 2 weeks in the Hooded Seal to 9-12 weeks in the Northern Elephant Seal. The physiological and behavioral adaptations that allow phocid pups to endure these remarkable fasts, which are among the longest for any mammal, remain an area of active study and research.
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Taxonmony
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Phylum: chordata
Class: mammalia
Order: Carnivora
Family: Phocidae
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Source: Wikipedia Read more about Seals and Sea Lions
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AUDIO CLIPS
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Sea Lion
0.120MB WAV Hear Sound
University of Aberdeen Zoology Museum
Sea lion sound
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Sea Lion
0.120MB WAV Hear Sound
University of Aberdeen Zoology Museum
Sea Lion
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California Sea Lion
0.120MB WAV Hear Sound
Naturesongs.com
California Sea Lion
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California Sea Lion
0.150MB WAV Hear Sound
Naturesongs.com
California Sea Lion
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Seal
0.010MB WAV Hear Sound
JungleWalk
Seal
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Seal
0.080MB WAV Hear Sound
JungleWalk
Seal
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Seal
0.190MB WAV Hear Sound
JungleWalk
Seal
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Sea Lion
0.010MB WAV Hear Sound
JungleWalk
Sea Lion
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Sea Lion
0.180MB WAV Hear Sound
JungleWalk
Sea Lion
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Weddell Seal
0.230MB WAV Hear Sound
Wild Sanctuary - The voice of the living world
Weddell seals have 34 different calls and can be heard for more than 15 miles underwater!
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Sea Lion
Streaming RAM Hear Sound
ThinkQuest
Sea lions bark. They snort to clear their nostrils after plunging into the water. This snippet presents to you the alarming barking sounds of the sea lions.
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California Sea Lion
Streaming RAM Hear Sound
The British Library
London Zoo
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Elephant Seal
0.320MB MP3 Hear Sound
Antarctica 2008
Male elephant seal bellowing
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Elephant Seal
0.380MB MP3 Hear Sound
Antarctica 2009
Juvenile elephant seal "plays" with the echo of its call in Arthur Harbor
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Leopard Seal
1.050MB MP3 Hear Sound
Antarctica 2010
Leopard seals and the sounds of icebergs fracturing recorded underwater
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Leopard Seal
0.670MB MP3 Hear Sound
Antarctica 2011
Leopard and Weddell seals recorded underwater and the sea ice edge in McMurdo Sound
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Weddell Seal
0.370MB MP3 Hear Sound
Antarctica 2012
Male Weddell seal(s) maritorial calling recorded underwater
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Weddell Seal
0.550MB MP3 Hear Sound
Antarctica 2013
Male Weddell seal(s) maritorial calling recorded underwater
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Weddell Seal
0.590MB MP3 Hear Sound
Antarctica 2014
Male Weddell seal(s) maritorial calling recorded underwater
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Weddell Seal
0.430MB MP3 Hear Sound
Antarctica 2015
Male Weddell seal(s) maritorial calling recorded underwater
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Weddell Seal
0.770MB MP3 Hear Sound
Antarctica 2016
Weddell Seal Mothers and Pups recorded at the surface
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Weddell Seal
0.370MB MP3 Hear Sound
EarthEar
Here, huge Weddell Seals form the centerpiece of a sonic community that also includes Orcas and Leopard Seals.. See details in the page below to buy the CD
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Weddell Seal
1.250MB MP3 Hear Sound
EarthEar
Doug Quin could hear the powerful territorial calls of these huge weddell seals through six feet of sea ice. See details in the page below to buy the CD
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Fur Seal
0.200MB WMA Hear Sound
David Antony Clark
Fur Seal call
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Seal
0.000MB WAV Hear Sound
e-Vet
Seal sound
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Sea lion
0.010MB WAV Hear Sound
e-Vet
Sea lion sound
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Sea lion
0.010MB WAV Hear Sound
e-Vet
Sea lion sound
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Sea lion
0.010MB WAV Hear Sound
e-Vet
Sea lion sound
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California Sea Lion
MP3 Hear Sound
National Geographic
California Sea Lion sound clip
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Elephant Seal
MP3 Hear Sound
National Geographic
Elephant Seal sound clip
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Harp Seal
MP3 Hear Sound
National Geographic
Harp Seal sound clip
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Hawaiian Monk Seal
MP3 Hear Sound
National Geographic
Hawaiian Monk Seal sound clip
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Leopard Seal
MP3 Hear Sound
National Geographic
Leopard Seal sound clip
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Fur Seal
MP3 Hear Sound
National Geographic
Fur Seal sound clip
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Weddell Seal
MP3 Hear Sound
National Geographic
Weddell Seal sound clip
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