ORDER CARNIVORA (PINNIPEDS AND MARINE FISSIPEDIA)

 

Mammalian Order



By far, the most Carnivores are terrestrial mammals. Besides pinnipeds, the order carnivore contains 7 Families of largely meat –eating mammals, including cats, dogs, bears, raccoons, weasels, otters, civets, and hyenas. Of these, only two Families Contain marine mammal representatives, the Mustelidae (Otter and Weasels) and the Ursidae (bears). As only 3 of these 200+ non-pinniped species of carnivores are marine mammals, we will not present the detailed characteristics of members of this order.

  1. SUB ORDER PINNIPEDIA- Seals, Sea lions and Walruses.
  2. SUB ORDER MARINE FISSIPEDIA- Otters And Polar Bears.

SUB ORDER PINNIPEDIA- Seals, sea lions and Walruses.

There are 36 species of pinnipeds, all of which are assigned to 3 families of the mammalian order carnivore: The otariidae, the phocidae and odobenidae. The otariids are the 14 species of sea lions and fur seals, sometimes referred to as the eared or walking seals. The Phocids are the 19 species of true seals, sometimes referred to as the earless true, or crawling seals. Odobenids are reduced to just a single living species, the walrus. There is controversy as to whether the pinnipeds are monophyletic (i.e., evolved from a single ancestor) or biphyletic (from 2 separate ancestors).

                                                                                 Pinnipeds are highly specialized aquatic carnivores that live in a diverse of marine habitats, and some freshwater ones as well. One unifying feature of the group is that all must return to a solid substrate, such as land or ice, to bear their pups. Female give birth to a single offspring per reproductive effort. Twins are extremely rare in all species. All species are amphibious, though the otariids are the most agile and mobile on land. In general, phocids are more capable diverse and breath-holders, although there is overlap in the capabilities of some otariids and phocids. Some species spend considerable amount of time in the water, only coming ashore to breed or give birth.

                                                                                Pinnipeds all have fur (but also use blubber for thermoregulation), 2 sets of limbs (called fore flippers and hind flippers), long whiskers, nasal openings at the tip of the snout, and reduced or lost ear flaps. Pinnipeds moult every year, some gradually over several weeks or months, others dramatically in a short time. In most species pups are born in lanugo coat which differ from juvenile or adult pelage in colour and length. In the species accounts below, pinniped coloration is described in more detail than for cetaceans, because for identification, there is often more of an emphasis on the subtle shading often visible  on hauled- out pinnipeds. 

FAMILIES OF PINNIPEDS:

 OTARIIDAE-Eared seals

All 16 species (in seven genera) of sea lions and fur seals have a polygynous mating system and pronounced sexual dimorphism. Characteristics of this family are; small external ear flaps (pinnae), smooth vibrissae, light skin, a double layer of fur with short underfur and longer guard hairs, hairless hindflippers, four teats in females, scrotal testes, and skulls with shelf-like supraorbital processes and sagittal crests (the latter enlarged in adult males only). Eared seals swim with their large fore flippers and can rotate their hindflippers forward to walk on all fours on land. Southern hemisphere fur seals rest in a characteristic posture, with head down and flippers swaying gently.

  • Steller sea lion-Eumetopias jubatus
  • California sea lion-Zalophus Californianus
  • Japanese sea lion-Zalophus Japonicus (Probably extinct)
  • Galapagos sea lion- Zalophus Wollebaeki
  • South American sea lion-Otaria Flavescens
  • Australian Sea lion-Neophoca Cinerea
  • Hooker’s (or) New Zealand sea lion-phocarctos Hookeri
  • Northern fur seal-Callorhinus Ursinus
  • Guadalupe fur seal-Arctocephalus Townsendi
  • Juan Fernandez Fur seal- Arctocephalus Philippii
  • Galapagos fur seal- Arctocephalus Galapagoensis
  • South American Fur seal- Arctocephalus Australis
  • New Zealand (or) Antipodean Fur seal- Arctocephalus Forsteri
  • Sub Antarctic fur seal- Arctocephalus Tropicalis
  • Antarctic fur seal- Arctocephalus Gazella
  • Cape and Australian (or) Brown fur seal- Arctocephalus Pusillus

PHOCIDAE-True seals

      This is the largest family of the pinnipeds, with 19 species in 13 genera (one in extinct).The true, or earless, seals include the largest of the pinnipeds, the elephant seals. Species within the group have variable degrees of sexual dimorphism (in some species, females are the larger sex).phocids are characterized by the absence of ear pinnae, a short muzzle, beaded vibrissae, dark skin, short fur, generally two teats in females, internal testes, furred hind flippers, inflated tympanoperiotic bones, and the absence of supraorbital processes or an enlarged sagittal crest on the skull. Propulsion in water is provided by figure-eight movements of the hindflippers, and movement on land is provided by inch-worming or “galumphing”, without much help from the relatively small fore flippers. They lack the ability to draw the hindflippers under the body to lift themselves off the ground. As a rule, true seals are more aquatic than eared seals, spending proportionately less time on land or ice.

  • Harbor Seal-phoca vitulina
  • Spotted Seal-phoca Largha
  • Ringed seal-Pusa hispida
  • Baikal Seal-Pusa Sibirica
  • Caspian Seal-pusa Caspica
  • Harp Seal-Pagophilus Groenlandicus
  • Ribbon Seal-Histriophoca Fasciatta
  • Gray Seal-Halichoerus Grypus
  • Bearded Seal-Erignathus Barbatus
  • Hooded Seal-Cystophora Cristata
  • Mediterranean Monk Seal-Monachus Monachus
  • West Indian (or) Caribbean Monk Seal-Monachus Tropicalis (Believed to be extinct)
  • Hawaiian Monk seal-Monachus Schauinslandi
  • Northern Elephant Seal-Mirounga Angustirostris
  • Southern Elephant seal-Mirounga leonina
  • Crab eater Seal-Lobodon Carcinophagus
  • Ross Seal-Ommatophoca Rossii
  • Leopard Seal-Hydrurga Leptonyx
  • Weddell seal-Leptonychotes Weddellii

Picture From Slide Share



ODOBENIDAE-Walrus

While there were multiple species in the past, today only a single walrus species persists. Walruses are enormous animals that combine features of both otariids (e.g., moderately long fore flippers that can lift the body off the ground) and the phocids (e.g., lack of ear pinnae). The neck is long and the hindflippers can rotate under the body and permit walking, although walruses are so bulky they cannot walk as easily as most otariids can. The tail is sheathed in skin and not readily visible or free, as in other pinnipeds. The tusks are a unique feature, and are important in fighting and assisting with hauling out. The walrus skull is very dense (pachyostotic) and has antorbital processes that are composed of both frontal and maxilla bones. Walruses have numerous short, smooth vibrissae on their thick fleshy mystical (“moustache”) pads. The testes of walruses are internal, not scrotal, and females have four retractable mammary teats. The skin is dark in younger animals and lightens with age. Walruses swim with phocid-like side-to-side strokes of the hindflippers, with assistance from the fore flippers. They only occur in high latitudes of the northern hemisphere.

  • Walrus-Odobenus Rosmarus

Picture From Slide Player


SUB ORDER MARINE FISSIPEDIA- Otters and bears.

FAMILIES OF MARINE FISSIPEDIA:

MUSTELIDAE-Otters

The mustelids are the otters, weasels, and their kin. Others mustelids include the minks, polecats, martens, wolverines, skunks, and badgers. Although four other species of freshwater otters may obtain some of their food from the sea, Only 2 of the 67 species in this family are truly marine, the sea otter and the marine otter. It is clear that “fresh water” otters in certain areas enter marine waters; however, we restrict our treatment to these two species usually considered among marine mammals. Otters are often classified in their own subfamily, the lutrinae containing 13 species).Marine and sea otters are largely restricted to the Pacific Ocean (two marine species in two genera).

  • Sea otter-Enhydra Lutris
  • Marine Otter-Lontra Felina

Picture From Pin Interest


URSIDAE- Polar Bears

There are 7 species of bears in the world; 6 are wholly terrestrial and only one qualifies as a marine mammal. Bears are very familiar animals to many people; in particular, the grizzly/brown and black bears of the Northern Hemisphere are often exhibited in zoos and are well known (grizzly/brown bears are most closely related to the polar bear). The single marine species, the polar bear, ranks as the least aquatic and least derived of all marine mammals. Polar bears may spend long periods of time on shore. They are restricted in distribution to arctic regions of the Northern Hemisphere.

  • Polar bear-Ursus Maritimus

Picture From Pin Interest



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