Otter
From Wikipedia, the free encyclopedia
Jump to navigationJump to search
This article is about the animal. For other uses, see Otter (disambiguation).
Otter
Temporal range: Late Miocene to present otter 1 otter
Fischotter, Lutra Lutra.JPG
Eurasian otter (Lutra lutra)
Scientific classification edit
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Mustelidae
Subfamily: Lutrinae
Bonaparte, 1838
Type genus
Lutra
Brünnich, 1771
Genera
Amblonyx
Aonyx
Enhydra
Hydrictis
Lontra
Lutra
Lutrogale
Pteronura
†Enhydriodon otter 2 otter otter 3 otter
†Algarolutra
†Cyrnaonyx
†Megalenhydris
†Sardolutra
†Siamogale
†Teruelictis
†Enhydritherium
†Limnonyx
†Lutravus
†Sivaonyx
†Torolutra
†Tyrrhenolutra
†Vishnuonyx
Otters are carnivorous mammals in the subfamily Lutrinae. The 13 extant otter
species are all semiaquatic, aquatic or marine, with diets based on fish and
invertebrates. Lutrinae is a branch of the weasel family Mustelidae, which also
includes badgers, honey badgers, martens, minks, polecats, and wolverines.
Contents
1 Etymology
2 Terminology
3 Life cycle
4 Characteristics
5 Species
5.1 European otter
5.2 North American river otter
5.3 Sea otter
5.4 Giant otter
6 Relation with humans
6.1 Hunting
6.2 Fishing for humans
6.3 Religion and mythology
6.3.1 Japanese folklore
7 References
8 External links
Etymology
The word otter derives from the Old English word otor or oter. This, and cognate
words in other Indo-European languages, ultimately stem from the
Proto-Indo-European language root *wódr̥, which also gave rise to the English
word "water". otter 4 otter otter 5 otter
Terminology
An otter's den is called a holt or couch. Male otters are called dogs or boars,
females are called bitches or sows, and their offspring are called pups. otter 6
otter The collective nouns for otters are bevy, family, lodge, romp (being
descriptive of their often playful nature) or, when in water, raft. otter 7
otter otter 8 otter
The feces of otters are typically identified by their distinctive aroma, the
smell of which has been described as ranging from freshly mown hay to putrefied
fish; otter 9 otter these are known as spraints. otter 10 otter
Life cycle
The gestation period in otters is about 60 to 86 days. The newborn pup is cared
for by the bitch, dog and older offspring. Bitch otters reach sexual maturity at
approximately two years of age and males at approximately three years. The holt
is built under tree roots or a rocky cairn, more common in Scotland. It is lined
with moss and grass.
After one month, the pup can leave the holt and after two months, it is able to
swim. The pup lives with its family for approximately one year. Otters live up
to 16 years; they are by nature playful, and frolic in the water with their
pups. Its usual source of food is fish, and further downriver, eels, but it may
sample frogs and birds.
Characteristics
Otters have long, slim bodies and relatively short limbs. Their most striking
anatomical features are the powerful webbed feet used to swim, and their
seal-like abilities holding breath underwater. Most have sharp claws on their
feet and all except the sea otter have long, muscular tails. The 13 species
range in adult size from 0.6 to 1.8 m (2.0 to 5.9 ft) in length and 1 to 45 kg
(2.2 to 99.2 lb) in weight. The Asian small-clawed otter is the smallest otter
species and the giant otter and sea otter are the largest. They have very soft,
insulated underfur, which is protected by an outer layer of long guard hairs.
This traps a layer of air which keeps them dry, warm, and somewhat buoyant under
water.
Several otter species live in cold waters and have high metabolic rates to help
keep them warm. European otters must eat 15% of their body weight each day, and
sea otters 20 to 25%, depending on the temperature. In water as warm as 10 °C
(50 °F), an otter needs to catch 100 g (3.5 oz) of fish per hour to survive.
Most species hunt for three to five hours each day and nursing mothers up to
eight hours each day.
For most otters, fish is the staple of their diet. This is often supplemented by
frogs, crayfish and crabs. otter 11 otter Some otters are experts at opening
shellfish, and others will feed on available small mammals or birds.
Prey-dependence leaves otters very vulnerable to prey depletion. Sea otters are
hunters of clams, sea urchins and other shelled creatures. They are notable for
their ability to use stones to break open shellfish on their stomachs. This
skill must be learned by the young. otter 12 otter
Otters are active hunters, chasing prey in the water or searching the beds of
rivers, lakes or the seas. Most species live beside water, but river otters
usually enter it only to hunt or travel, otherwise spending much of their time
on land to prevent their fur becoming waterlogged. Sea otters are considerably
more aquatic and live in the ocean for most of their lives.
Otters are playful animals and appear to engage in various behaviors for sheer
enjoyment, such as making waterslides and then sliding on them into the water.
They may also find and play with small stones. Different species vary in their
social structure, with some being largely solitary, while others live in groups
– in a few species these groups may be fairly large.
Species
Lutrinae
Giant otter (Pteronura brasiliensis)
North American river otter (Lontra canadensis)
Marine otter (Lontra felina)
Southern river otter (Lontra provocax)
Neotropical river otter (Lontra longicaudis)
Sea otter (Enhydra lutris)
Spotted-necked otter (Hydrictis maculicollis)
Eurasian otter (Lutra lutra)
Hairy-nosed otter (Lutra sumatrana)
Japanese otter†
Lutra euxena†
Lutra castiglionis†
Lutra simplicidens†
Lutra trinacriae†
African clawless otter (Aonyx capensis)
Asian small-clawed otter (Aonyx cinerea)
Smooth-coated otter (Lutrogale perspicillata)
Cladogram, after Koepfli et al. 2008 otter 1 otter and Bininda-Emonds et al.
1999 otter 13 otter
Genus Lutra
Eurasian otter (Lutra lutra)
Hairy-nosed otter (Lutra sumatrana)
Japanese otter† (Lutra nippon)
Lutra euxena†
Lutra castiglionis†
Lutra simplicidens†
Lutra trinacriae†
Genus Hydrictis
Spotted-necked otter (Hydrictis maculicollis)
Genus Lutrogale
Smooth-coated otter (Lutrogale perspicillata)
Lutrogale robusta†
Genus Lontra
North American river otter (Lontra canadensis)
Southern river otter (Lontra provocax)
Neotropical river otter (Lontra longicaudis)
Marine otter (Lontra felina)
Genus Pteronura
Giant otter (Pteronura brasiliensis)
Genus Amblonyx
Asian small-clawed otter (Amblonyx cinereus)
Genus Aonyx
African clawless otter (Aonyx capensis)
Genus Enhydra
Sea otter (Enhydra lutris)
Enhydra reevei†
Genus †Megalenhydris
Genus †Sardolutra
Genus †Algarolutra
Genus †Cyrnaonyx
Genus †Teruelictis
Genus †Enhydriodon
Genus †Enhydritherium
Genus †Teruelictis
Genus †Limnonyx
Genus †Lutravus
Genus †Sivaonyx
Genus †Torolutra
Genus †Tyrrhenolutra
Genus †Vishnuonyx
Genus †Siamogale
European otter
Main article: European otter
European otter, England
The European otter (Lutra lutra), also called the Eurasian otter, inhabits
Europe, most of Asia and parts of North Africa. In the British Isles, they were
common as recently as the 1950s, but became rare in many areas due to the use of
chlorinated hydrocarbon pesticides, habitat loss and water pollution (they
remained relatively common in parts of Scotland and Ireland). Population levels
reached a low point in the 1980s, but are now recovering strongly. The UK
Biodiversity Action Plan envisages the re-establishment of otters by 2010 in all
the UK rivers and coastal areas they inhabited in 1960. Roadkill deaths have
become one of the significant threats to the success of their re-establishment.
North American river otter
Main article: North American river otter
North American river otters
The North American river otter (Lontra canadensis) became one of the major
animals hunted and trapped for fur in North America after European contact.
River otters eat a variety of fish and shellfish, as well as small land mammals
and birds. They grow to one meter (3 to 4 ft) in length and weigh from five to
15 kilograms (10 to 30 lb).
In some areas, this is a protected species, and some places have otter
sanctuaries that help sick and injured otters to recover.
Sea otter
Main article: Sea otter
Sea otter in Morro Bay, California
Sea otters (Enhydra lutris) are classified as marine mammals and live along the
Pacific coast of North America. Their historic range included shallow waters of
the Bering Strait and Kamchatka, and as far south as Japan. Sea otters have
about 26,000 to 165,000 hairs per square centimeters of skin, otter 14 otter a
rich fur for which humans hunted them almost to extinction. By the time the 1911
Fur Seal Treaty gave them protection, so few sea otters remained that the fur
trade had become unprofitable. Sea otters eat shellfish and other invertebrates
(especially clams, abalone, and sea urchins). otter 15 otter Otter populations
are affected by the density of prey they hunt. Because the otter food source is
easier to excavate from rocky-bottom habitats, as opposed to soft-bottom
habitats, more otters tend to live in waters with rocky bottoms with access to
shallow-burrowing prey. otter 16 otter They frequently carry a rock in a pouch
under their forearm and use this to smash open shells, making them one of the
relatively small number of animals that use tools. They grow to 1.0 to 1.5 m
(3.3 to 4.9 ft) in length and weigh 30 kg (66 lb). Although once near
extinction, they have begun to spread again, from remnant populations in
California and Alaska.
Unlike most marine mammals (such as seals or whales), sea otters do not have a
layer of insulating blubber. otter 15 otter As with other species of otter, they
rely on a layer of air trapped in their fur, which they keep topped up by
blowing into the fur from their mouths. They spend most of their time in the
water, whereas other otters spend much of their time on land.
Giant otter
Main article: Giant otter
Giant otter
The giant otter (Pteronura brasiliensis) inhabits South America, especially the
Amazon river basin, but is becoming increasingly rare due to poaching, habitat
loss, and the use of mercury and other toxins in illegal alluvial gold mining.
This gregarious animal grows to a length of up to 1.8 m (5.9 ft), and is more
aquatic than most other otters.
Relation with humans
Sign warning drivers in Benbecula in the Outer Hebrides to beware otters on the
road
Hunting
Otters have been hunted for their pelts from at least the 1700s, although it may
have begun well before then. Early hunting methods included darts, arrows, nets
and snares but later, traps were set on land and guns used.
There has been a long history of otter pelts being worn around the world. In
China it was standard for the royalty to wear robes made from them. People that
were financially high in status also wore them. The tails of otters were often
made into items for men to wear. These included hats and belts. Even some types
of mittens for children have been made from the fur of otters. otter 17 otter
Otters have also been hunted using dogs, specifically the otterhound. otter 18
otter From 1958 to 1963, the 11 otter hunts in England and Wales killed 1,065
otters between them. In such hunts, the hunters notched their poles after every
kill. The prized trophy that hunters would take from the otters was the penis
bone, which would be worn as a tie-pin. otter 19 otter
Traffic (the wildlife trade monitoring network) reported that otters are at
serious risk in Southeast Asia and have disappeared from parts of their former
range. This decline in populations is due to hunting to supply the demand for
skins. otter 20 otter
Fishing for humans
Main article: Otter fishing
For many generations, fishermen in southern Bangladesh have bred smooth-coated
otters and used them to chase fish into their nets. Once a widespread practice,
passed down from father to son throughout many communities in Asia, this
traditional use of domesticated wild animals is still in practice in the
district of Narail, Bangladesh. otter 21 otter otter 22 otter
Religion and mythology
Norse mythology tells of the dwarf Ótr habitually taking the form of an otter.
The myth of "Otter's Ransom" otter 23 otter is the starting point of the
Volsunga saga.
In some Native American cultures, otters are considered totem animals. otter 24
otter
The otter is held to be a clean animal belonging to Ahura Mazda in Zoroastrian
belief, and taboo to kill. otter 25 otter
In popular Korean mythology, it is told that people who see an otter (soodal)
will attract 'rain clouds' for the rest of their lives. otter citation needed
otter
Japanese folklore
"Kawauso" (獺) from the Gazu Hyakki Yagyō by Sekien Toriyama
In Japanese, otters are called "kawauso" (獺、川獺). In Japanese folklore, they fool
humans in the same way as foxes (kitsune) and tanuki.
In the Noto region, Ishikawa Prefecture, there are stories where they shapeshift
into beautiful women or children wearing checker-patterned clothing. If a human
attempts to speak to one, they will answer "oraya" and then answer "araya," and
if anybody asks them anything, they say cryptic things like "kawai." otter 26
otter otter 27 otter There are darker stories, such as one from Kaga Province
(now Ishikawa Prefecture) in which an otter that lives in the castle's moat
shapeshifts into a woman, invites males, and then kills and eats them. otter 28
otter
In the kaidan, essays, and legends of the Edo period like the "Urami Kanawa"
(裏見寒話), otter 29 otter "Taihei Hyaku Monogatari" (太平百物語), and the "Shifu Goroku"
(四不語録), there are tales about strange occurrences like otters that shapeshift
into beautiful women and kill men. otter 27 otter
In the town of Numatachi, Asa District, Hiroshima Prefecture (now Hiroshima),
they are called "tomo no kawauso" (伴のカワウソ) and "ato no kawauso" (阿戸のカワウソ). It is
said that they shapeshift into bōzu (a kind of monk) and appear before
passers-by, and if the passer-by tries to get close and look up, its height
steadily increases until it becomes a large bōzu. otter 30 otter
In the Tsugaru region, Aomori Prefecture, they are said to possess humans. It is
said that those possessed by otters lose their stamina as if their soul has been
extracted. otter 31 otter They are also said to shapeshift into severed heads
and get caught in fishing nets. otter 31 otter
In the Kashima District and the Hakui District in Ishikawa Prefecture, they are
seen as a yōkai under the name kabuso or kawaso. They perform pranks like
extinguishing the fire of the paper lanterns of people who walk on roads at
night, shapeshifting into a beautiful woman of 18–19 years of age and fooling
people, or tricking people and making them try to engage in sumo against a rock
or a tree stump. otter 27 otter It is said that they speak human words, and
sometimes people are called and stopped while walking on roads. otter 32 otter
In the Ishikawa and Kochi Prefectures, they are said to be a type of kappa, and
there are stories told about how they engage in sumo with otters. otter 27 otter
In places like the Hokuriku region, Kii, and Shikoku, the otters are seen as a
type of kappa. otter 33 otter In the Kagakushū, a dictionary from the Muromachi
period, an otter that grew old becomes a kappa. otter 34 otter
In an Ainu folktale, in Urashibetsu (in Abashiri, Hokkaido), there are stories
where monster otters shapeshift into humans, go into homes where there are
beautiful girls, and try to kill the girl and make her its wife. otter 35 otter
In China, like in Japan, there are stories where otters shapeshift into
beautiful women in old books like In Search of the Supernatural and the
Zhenyizhi (甄異志). otter 29 otter
For Doc Brown's
latest updates of pictures or science see https://twitter.com/docbrownchem
Doc Brown's
Science Website - GCSE Biology, GCSE & A Level Chemistry and GCSE Physics
TOP OF PAGE
Enter
anything of interest
*