Otter is the common name for
any of the 13 species that make up the taxonomic subfamily
Lutrinae, which is part of the family Mustelidae (weasels,
otters & badgers).
Otters are carnivorous weasel-like mammals that survive,
with two exceptions, in both freshwater and land environments.
The exceptions are the Sea
lutris, which is a strictly marine habitat species,
and the Marine Otter, Lontra felina,
which lives in marine and estuarine environments.
Otters can be found in rivers, streams, lakes, marshes,
estuaries, and marine coasts throughout the world. They
always stay in close proximity to water, though they do
sleep on land (the exception again being the sea otter).
They mark their territories with anal scent glands, as
do most members of the Mustelidae family.
Like weasels, otters have long, slender bodies and short
legs. Their tales are thick and muscular, as they help
otters to maneuver in water. Paws are webbed for swimming,
and most species have claws.
All otters have a very think coat of fur which is comprised
of a soft, dense undercoat and a course overcoat. The two
layers of fur trap air between them, which serves to keep
the otter warm while in the water. This is in contrast
to seals, which have a layer of blubber to keep them warm.
Otters have a high metabolic rate and must eat a lot to
maintain their body temperature in the cool water. River
otters eat about 15% of their body weight each day, while
sea otters must eat a whopping 25% of their body weight
per day. Their main diet is fish, but they also eat crabs,
frogs, crayfish and shellfish. Birds and small mammals
are also occasionally on the menu.
Otters are notable for being among the fairly small list
of animals that can use tools (others being apes, dolphins,
elephants and several species of bird). Sea otters have
been observed placing a rock on their chest while floating
on their back to use for cracking open shellfish.
Most species of otter are threatened or endangered. They
are particularly susceptible to environmental degradation.
Pollution, loss of habitat, agricultural runoff, and hunting
are some of the threats they face. Coastal oil spills are
a particularly fatal menace, as the oil covers their fur,
rendering it useless for protection from the cold.
Otters, Subfamily Lutrinae
Stock photo of African clawless otter or Cape clawless otter, Aonyx capensis, Widespread, though not abundant, in Africa, south of the Sahara
Picture #: 104678
Photo of Asian small-clawed otters or oriental small-clawed
cinereus, adult pair
Picture #: 102821
Picture of Congo Clawless Otter or Cameroon Clawless Otter, Aonyx
Picture #: 102755
Image of southern sea otter or California sea otter, Enhydra
lutris nereis, resting, note limbs are kept
out of water and crossed to keep warm, Monterey Bay
National Marine Sanctuary, California, Pacific Ocean,
Picture #: 096026
Image of North American river otter, northern river
otter, or Canadian river otter, Lontra
Picture #: 102719
Picture of southern river otter, Chilean otter or South American river otter, Lontra provocax, endangered species
Picture #: 103387
of neotropical otter or long-tailed
otter, Lontra longicaudis, Pantanal, Brazil
Picture #: 102813
Stock photo of Marine Otter, Lontra felina, endangered,
Chiloe Island, Chile, Pacific Ocean
Picture #: 067847
Stock photo of Eurasian otters, common otters or European otters, Lutra
Photo of hairy-nosed otter, Lutra sumatrana
Picture of African Spotted-necked Otter, Lutra maculicollis
Picture #: 027997
Image of Smooth-coated Otter, Indian smooth-coated otter or smooth otter, Lutrogale perspicillata, feeding
Picture #: 102828
Image of giant otter, Pteronura brasiliensis, the
largest otter species, endanged species, Pantanai, Brazil
Picture #: 102729
Interestingly, there appears to be a special vocabulary
related to otters. Following is a short glossary of terms
as found in Wikipedia's Otter article:
male otter: dog-otter
female otter: bitch
baby otters: cubs
group of otters: romp
otter den: holt
otter dung: spraint or scat
On the subject of Lutrinae taxonomy, there are some differences
among taxonomists in how Lutrinae are classified. In the
past, American otters were classified as genus Lutra, but
now they are often found in their own genus, Lontra, i.e.,
new world otters. Also, Spotted necked otters are sometimes
classified in their own genus, Hydrictis, as in Hydrictis
maculicollis. SeaPics.com photographers, depending on the
source they use, may arrive at different Latin names. They
may choose to categorize a Northern river otter, for example,
as Lontra Canadensis or Lutra Canadensis.
© Lutrinae information assembled from published and on-line
sources by Kevin
Miler for SeaPics.com. Dec. 14, 2007.