100 Fun Facts About Otter

Otters belong to which animal family, also known for weasels and badgers?

Mustelidae is the weasel family; otters form its Lutrinae subfamily beside badgers, martens and minks.

Approximately how many extant species of otter are recognized worldwide?

They range in adult size from 0.6 to 1.8 metres and from 1 to 45 kilograms, and can live up to 16 years.

For generations, fishermen in southern Bangladesh have bred which otter species to chase fish into their nets?

Smooth-coated otters do the herding; the practice, once widespread across Asia and passed from father to son, survives in the district of Narail.

What is the staple of most otters' diets?

Fish is the staple of most otters' diets, supplemented by frogs, crayfish and crabs; otters locate prey underwater with their sensitive whiskers.

What is a common term for an otter's den or burrow?

A holt is the otter's den; a badger has a sett, a squirrel a drey and a beaver a lodge.

With no blubber to keep it warm, which marine mammal has the thickest fur of all, around 160,000 hairs per square centimetre?

The sea otter has no blubber and relies on the densest fur of any mammal, up to about a million hairs per square inch; the underfur traps a layer of insulating air against the skin.

Sea otters are among the few mammals that use tools; what do they use to dislodge prey and crack shells open?

Rocks, banged against shells, put sea otters in a very small club of tool-using mammals.

What are the single-sex resting groups of ten to a hundred sea otters called?

These resting groups are called rafts; male rafts are typically larger than female ones, and the largest ever recorded held more than 2,000 sea otters.

Which 1.8-metre Amazon species is the longest member of the weasel family?

The giant otter, up to 1.8 metres long, is the longest member of the weasel family; the Guianas and the Peruvian Amazon remain its strongholds.

Weighing at most 3.5 kg and measuring under a metre nose to tail, which is the smallest of these species?

The Asian small-clawed otter is the world's smallest otter, measuring 73 to 96 cm nose to tail and weighing no more than about 3.5 kg.

'Otter', from Old English 'otor', shares a Proto-Indo-European root with which everyday English word?

Both 'otter' and 'water' descend from the Proto-Indo-European root *wódr̥, the word for water; the Old English form of the animal's name was otor.

In water as warm as 10 °C, roughly how much fish does an otter need to catch per hour to survive?

About 100 grams of fish an hour is the survival minimum in 10 °C water; otters have high metabolic rates and rely on air trapped in their fur to stay warm.

In Norse myth, which god killed the dwarf Ótr while he was in otter form?

Loki struck Ótr with a stone as he ate a salmon in otter form; Ótr's father Hreidmar then demanded the weregild that became the cursed gold of the Völsung saga.

In Japanese folklore the otter, or kawauso, tricks humans in the same way as which two other shapeshifting animals?

Foxes and tanuki are the otter's fellow tricksters; stories from Ishikawa Prefecture have kawauso shapeshifting into beautiful women or children in checked clothing.

Which religion classes the otter as a clean animal whose killing is a grave sin?

In Zoroastrianism the otter is a clean creature of Ahura Mazda; the Vendidad devotes a chapter to the heavy penalties for killing a 'water dog', its word for the otter.

The Japanese otter, Lutra nippon, is believed to have gone extinct in roughly which year?

The Japanese otter was last officially sighted in 1979, at Susaki in Kōchi Prefecture; Japan's Environment Ministry formally declared the species extinct in 2012.

Between 1741 and 1911 the world sea otter population was hunted for fur down to roughly how many animals?

The fur trade cut a population once estimated at 150,000 to 300,000 down to just 1,000 to 2,000 animals by 1911, when an international treaty banned the hunt.

Sea otters protect kelp forests by controlling populations of what?

Sea urchins would otherwise inflict extensive damage on kelp forests; to stay warm, sea otters must eat an estimated 25 to 38 percent of their body weight every day.

Where on its body does a sea otter store collected food, and sometimes a favourite rock, while diving?

A loose skin pouch under each foreleg, mostly the left one, holds prey and a favourite rock; freeing an abalone clinging with 4,000 times its weight can take several dives.

To avoid drifting out to sea while resting, sea otters wrap themselves in what?

Mothers also anchor floating pups in kelp while they forage; a groomed newborn holds so much air it floats like a cork and cannot dive.

Gavin Maxwell's 1960 bestseller about living with otters on the Scottish coast is titled what?

Ring of Bright Water takes its title from Kathleen Raine's 1952 poem 'The Marriage of Psyche'; the 1969 film starred Bill Travers and Virginia McKenna.

Gavin Maxwell's otter Mijbil, brought back from the marshes of Iraq, was found by London Zoo to be what?

Mijbil proved to be a previously unknown subspecies of the smooth-coated otter, named Lutrogale perspicillata maxwelli, or Maxwell's otter, in his honour.

Henry Williamson's 1927 novel Tarka the Otter is set in which English county?

Tarka roams the Taw and Torridge rivers of north Devon; the novel won the 1928 Hawthornden Prize and gave its name to the Tarka Trail.

According to Henry Williamson, the name 'Tarka' means what?

When the book appeared otters were widely seen as vermin; Tarka and its 1979 film are credited with changing public attitudes.

The earliest records of fishing with trained otters come from China's Yangtze region in which dynasty?

Fishing with trained otters on the Yangtze is first recorded in China's Tang dynasty (618–907); the otters were trained to drive fish into the fishermen's nets.

The marine otter of Chile and Peru, the smallest marine mammal, is known in Spanish by what nickname?

Chileans call the marine otter gato marino ('sea cat'); its scientific name Lontra felina likewise means 'feline otter', and it weighs only 3 to 5 kg.

The giant otter's Brazilian nickname onça-d'água likens it to which animal?

Onça-d'água means 'water jaguar', onça being the Portuguese word for the jaguar; the giant otter is also called ariranha and lives in family groups of three to eight.

Giant otter poaching for its pelt peaked in which decades, leaving fewer than 5,000 in the wild?

Pelt hunting peaked in the 1950s and 1960s, when giant otter skins left the Amazon by the thousand; the IUCN listed the species as endangered in 1999.

At which CITES level has the Asian small-clawed otter been listed since August 2019?

CITES CoP18 in Geneva voted in August 2019 to move the Asian small-clawed otter from Appendix II to Appendix I, banning international commercial trade in the species.

The African clawless otter ranks where in size among freshwater otters?

The African clawless otter is the second-largest freshwater otter, behind only the giant otter; its genus name Aonyx means 'without claw' and its feet are only partly webbed.

The sea otter's genus name Enhydra comes from Ancient Greek words meaning what?

Enhydra joins the Greek en, 'in', to hydra, 'water', so the name means 'in the water'; the species name lutris comes from the Latin for otter.

How long can a sea otter hold its breath at most, even though typical dives last about a minute?

A sea otter can stay under for up to five minutes, though foraging dives usually last about a minute; it rolls in the water while eating to wash scraps from its fur.

Which 1989 disaster killed thousands of sea otters in Alaska's Prince William Sound?

The Exxon Valdez oil spill killed thousands of sea otters in 1989; the species had earlier been wiped out off Vancouver Island by 1929, before 89 were flown in from Alaska in 1969-72.

A naturalist of which nationality first scientifically described the North American river otter in 1777?

The German naturalist Johann Christian Daniel von Schreber described the species as Lutra canadensis in 1777; large males can top 15 kg.

River otters reintroduced to which US state in the early 1990s recovered so well that trapping reopened in 2006?

Kentucky reintroduced river otters in the early 1990s, and by 2006 they had spread through the state's major waterways well enough for a regulated trapping season to reopen.

By 1990 the Eurasian otter was considered extinct in which two neighbouring countries?

Switzerland and Liechtenstein had both lost the Eurasian otter by 1990, Switzerland declaring it extinct in 1989, after river pollution and channelisation destroyed its habitat.

In cold weather Eurasian otters broaden their fish diet to include what unexpected prey?

In winter, when fish are scarcer, Eurasian otters turn to amphibians, crustaceans, insects, birds and small mammals, including young beavers.

In 2021 a British man was ambushed by about 20 otters in the botanic gardens of which city?

The attack happened in the Singapore Botanic Gardens in November 2021; the victim said another jogger had stepped on an otter moments earlier, and he was bitten on his legs and fingers.

Excluding delayed implantation, how long is gestation in most otter species?

Most otter species carry their young for 60 to 86 days; river and sea otters can also delay implantation, stretching the whole pregnancy to many months.

The spotted-necked otter of Africa is the sole member of which genus?

The spotted-necked otter is Hydrictis maculicollis, the only species in its genus; Lontra holds the New World river otters, Aonyx the clawless otters and Lutrogale the smooth-coated otter.

Under what name did Linnaeus first describe the sea otter in 1758?

Linnaeus named the sea otter Mustela lutris in his 1758 Systema Naturae, grouping it with the weasels; it was later moved to Lutra as Lutra marina before the genus Enhydra was erected.

In Russian, the Asian sea otter is known by what name?

Kalan (калан) is the Russian name for the sea otter; the Asian subspecies lives mainly off Kamchatka, the Kuril Islands and the Commander Islands.

Which institution first raised a sea otter from conception to adulthood, with Tichuk in 1979?

The Seattle Aquarium was the first institution to breed and rear a sea otter, with Tichuk's birth in 1979; it later housed Etika, the oldest recorded female, who reached 28.

A 2007 viral video of two sea otters holding paws was filmed where?

The clip was shot at the Vancouver Aquarium; Nyac, the lighter otter, was a survivor of the 1989 Exxon Valdez spill and died in 2008 at about 20.

Which streamer has raised over $1 million for Monterey Bay Aquarium in honour of Rosa the sea otter?

DougDoug's Rosa birthday charity streams have raised more than $1 million for the Monterey Bay Aquarium; Rosa was rescued as a stranded pup and became the aquarium's oldest sea otter.

The sea otter was formerly sometimes referred to as the 'sea' what?

Early traders called the sea otter the 'sea beaver', and Russian hunters likewise called it morskoi bobr; its pelts were the foundation of the Pacific maritime fur trade.

Georg Steller’s crew, shipwrecked in 1741, spent the winter hunting sea otters where?

Bering's ship St. Peter wrecked on uninhabited Bering Island in the Commander Islands; the survivors reached Kamchatka in 1742 with about 900 sea otter pelts, launching the 'Great Hunt'.

After Captain Cook's crew sold sea otter pelts in China in the 1770s, the furs earned what nickname?

Sea otter pelts became known as 'soft gold'; Cook's men had bought them at Nootka Sound in 1778 and sold them in Canton for astonishing prices, sparking the maritime fur trade.

In 1799, Tsar Paul I consolidated rival fur hunters into which chartered monopoly?

The Russian-American Company received its charter from Paul I in 1799 with a monopoly on the Alaskan fur trade; Alexander I later put naval officers in charge after reports of abuse of the Aleuts.

In 1812 the Russians founded which northern California settlement as their southern headquarters?

Fort Ross, founded by Ivan Kuskov, was the Russian-American Company's southern base; his Aleut hunters had taken 1,160 sea otters in San Francisco Bay in just three months.

California’s sea otters all descend from about 50 animals found in 1938 near which landmark?

A colony of about 50 sea otters was spotted near Bixby Creek Bridge on the Big Sur coast in 1938, in a state whose historic population had been put at 16,000.

In the late 1980s the US relocated about 140 southern sea otters where, as a reserve colony?

About 140 otters were moved to San Nicolas Island in the Channel Islands from 1987 to 1990; most swam back to the mainland or vanished, and by 2005 only about 30 remained.

Which parasite, spread via cat feces in urban runoff, is a major killer of California sea otters?

Toxoplasma gondii, a protozoan whose oocysts wash into the sea from cat faeces, infects California sea otters and can cause fatal brain inflammation.

In California, which animal is the sea otter's main predator despite not actually eating them?

Great white sharks bite but do not eat sea otters, apparently mistaking them for seals; the share of otter carcasses with shark bites rose from 8% in the 1980s to 30% by 2011.

The sea otter is the only marine mammal that catches fish using what, rather than its teeth?

The sea otter grabs fish with its forepaws rather than its teeth, the only marine mammal to do so; it is also the only marine animal known to lift and turn over rocks while foraging.

Sea Otter Awareness Week is held every year during the last full week of which month?

Sea Otter Awareness Week falls in the last full week of September; Defenders of Wildlife, the Monterey Bay Aquarium and Sea Otter Savvy are among the groups that organise it.

The cry of a sea otter pup is often compared to the call of which bird?

A sea otter pup's cry is often compared to a gull's; content females coo, males tend to grunt, and frightened adults may whistle, hiss or scream.

Mikio Igarashi's long-running manga starring a sea otter is titled what?

Sea otters have become hugely popular in Japanese media; one is also in the main cast of the web manga Chiikawa.

Japan's only confirmed wild sea otter population lives off which island?

Japan's only wild sea otters live off eastern Hokkaido, where animals that drifted south from the Kuril Islands began breeding in the late 2010s.

Unlike most marine mammals, the sea otter supplements its water intake by doing what?

Drinking seawater is how the sea otter tops up its water intake; its relatively large kidneys extract fresh water from the brine and excrete very concentrated urine.

Otter 841, who stole surfboards from surfers in 2023, operated off which California city?

Otter 841 harassed surfers off Santa Cruz, around Steamer Lane, in the summer of 2023; she was born at the Monterey Bay Aquarium to a rescued mother, Otter 723, before being released into the wild.

The North American river otter's scientific species name refers to which country?

Lontra canadensis means 'otter of Canada', though the species also ranges across most of the United States, including Alaska.

What is the transparent inner eyelid that protects a river otter's eyes while swimming called?

The nictitating membrane, a transparent third eyelid, sweeps across the eye to protect it and lets the otter see underwater; its ears and nostrils also close when it dives.

Sutro Sam, spotted in San Francisco in 2012, was the city's first river otter since when?

Sutro Sam, who lived in the ruins of the Sutro Baths at Lands End, was the first river otter recorded in San Francisco since the 1950s.

After fish, what is the second-most important prey for North American river otters?

Crayfish are the river otter's second-most important prey after fish; in one central California marsh they made up nearly 100% of the diet at certain times of year.

Which is the only Canadian province where the river otter was wiped out province-wide?

Prince Edward Island is the only Canadian province where the river otter was extirpated entirely; the species persisted across the other nine provinces and the territories.

How many toes does a North American river otter have on each webbed foot?

River otters have five webbed toes on each foot, tipped with non-retractable claws; the webbed hind feet provide most of the thrust when swimming.

A 2011 review of otter attacks on humans from 1875 to 2010 found most happened in which US state?

Florida, where human and otter populations have both grown substantially since 2000, led the list; at least 42 attacks were found, and 36% of anecdotal reports involved rabid otters.

Which otter species carries the scientific name Lutra lutra?

Lutra lutra is the Eurasian otter, the type species of its genus; its range runs from Ireland across Europe and Asia to Kamchatka, with outposts in North Africa.

The giant otter's genus name Pteronura comes from Greek words meaning what?

Pteronura joins the Greek pteron, 'wing' or 'feather', to oura, 'tail', so the name means 'wing tail'; the flattened tail can add 70 cm to the giant otter's length.

Individual giant otters can be identified from birth by unique pale markings on which body part?

Each giant otter carries a unique cream or white throat patch from birth, letting researchers tell family members apart without tagging.

Besides humans, which animal has been recorded preying on giant otters in Peru?

A black caiman has been recorded killing a giant otter in Peru; adults in family groups have no serious natural predators, but caimans, jaguars and anacondas may take lone animals or pups.

Peru’s Alto Purús National Park, a 2004 giant otter refuge, is about the size of which country?

Alto Purús National Park, created in 2004, covers about 25,000 km², roughly the area of Belgium, and is Peru's largest national park.

The Spanish name lobo de río, used for the giant otter, translates as what?

Lobo de río means 'river wolf', a nod to the giant otter's size and pack-like family groups; perro de agua, 'water dog', is also used but is shared with several other animals.

In a Bororó legend, people who swallowed which leaf were punished by becoming giant otters?

In the Bororó origin legend of tobacco, people who swallowed the leaf instead of smoking it were turned into giant otters; the Bororó also link the animal with fish and with fire.

The Achuar people regard giant otters as a form of the tsunki, which are what?

The Achuar see giant otters as a form of the tsunki, water spirits of the rivers whom the Achuar and neighbouring Shuar also regard as the first shamans.

In 2021 a wild giant otter was spotted in which Argentine national park?

The otter was seen on the Bermejo River in Impenetrable National Park by Fundación Rewilding Argentina staff; the species had been thought extirpated from Argentina for decades.

What is the name for the faeces a Eurasian otter uses to mark its territory?

Spraints are the otter's droppings, left on prominent rocks and logs as scent marks; territories are defended only against the same sex, so a male's range often overlaps several females'.

In Andalusia, Eurasian otters have taken to using artificial lakes on what kind of site?

Otters on Andalusia's coast have colonised the artificial lakes of golf courses; even coastal otters need regular access to fresh water to rinse salt from their fur.

In August 2011 otters were declared to have returned to every county of which country?

The Environment Agency reported in August 2011 that otters were back in every county of England, Kent being the last; in the 1970s they survived only in the West Country and parts of the north.

The Eurasian otter's late-20th-century crash was driven mainly by which kind of pollution?

PCBs and farm pesticides, above all organochlorines such as dieldrin, drove the crash; a 1979 EEC directive banning the worst organochlorines underpinned the otter's later recovery.

To open shellfish without crushing them, captive Asian small-clawed otters were seen doing what?

Sun-warming the shells was the trick: captive Asian small-clawed otters left molluscs in the sun until the warmth made the shells gape open.

The small-clawed otter was described in 1815 from a specimen from Batavia, now which city?

Batavia was the Dutch colonial name for Jakarta; Johann Karl Wilhelm Illiger named the species Lutra cinerea from that specimen in 1815.

Most small-clawed otters seized from traffickers in 2015–18 were bound for which country?

Japan was the destination for 35 of the 49 small-clawed otters seized from traffickers between 2015 and 2018, feeding the demand from otter cafés and pet keepers there.

Smooth-coated otters in Kuala Selangor were seen hunting in what formation across a creek?

The otters formed a V-shaped line across the creek, with the largest animals in the middle, driving panicked fish ahead of them before grabbing them with their snouts.

Vagrant marine otters from Chile have occasionally been sighted as far afield as where?

Hunting wiped the marine otter out of most of Argentina and the Falkland Islands, where it has since been recorded only as a vagrant from Chile.

Which species is considered the rarest otter in Asia?

The hairy-nosed otter is Asia's rarest, locally extinct in India, Singapore and Myanmar; as of 2010 a single captive animal was known, at a wildlife centre in Cambodia.

The spotted-necked otter is common in which large African body of water?

Spotted-necked otters are common in Lake Victoria and in Zambia; they shun salt water and are oddly absent from the Zambezi below Victoria Falls.

In Mapuche culture, the southern river otter is known by what name?

Huillín is the Mapuche name for the southern river otter, Lontra provocax, which lives in the lakes and rivers of Chilean and Argentine Patagonia.

Which otter, at home from sewage works to glacial Andean lakes, is called the greatest generalist?

The Neotropical otter (Lontra longicaudis) is the most adaptable otter, settling in wastewater treatment plants, rice paddies, sugar-cane plantations and glacial Andean lakes alike.

South Africa's Otter Trail, named for the African clawless otter, runs through which national park?

The Otter Trail runs about 45 km along the Tsitsikamma coast from Storms River Mouth to Nature's Valley; the otters there hunt mullet in the shallow surf and scavenge along beaches.

In Gabon, a myth holds that Congo clawless otters can do what when caught with a spear?

Gabonese lore says the Congo clawless otter can give electric shocks when speared, a reputation that keeps it off the bushmeat menu there, unlike in Congo and Cameroon.

An otter fetching a fish for its master appears on which famous 1539 map of Scandinavia?

The Carta marina, Olaus Magnus's 1539 map of the Nordic lands, shows a tame otter bringing a fish to its master; in his 1555 history Magnus wrote that such otters sometimes forget and eat the fish.

Which 1653 book on angling by Izaak Walton describes how to train otters to fish?

The Compleat Angler explains that otter pups of three to four months were muzzled, leashed and taught to chase pond fish into a net.

Otter hunting ended in England and Wales in which year, once the animal was protected?

Otter hunting ended in England and Wales in 1978, once the otter joined the protected list; nine registered Otterhound packs existed in 1977, and some switched to hunting mink or coypu.

Which bone did British otter hunters take as a trophy and wear as a tie-pin?

The baculum, the penis bone, was the prize; hunters also notched their poles after every kill, and 11 English and Welsh hunts killed 1,065 otters between 1958 and 1963.

In Korean folklore, seeing an otter (soodal) makes a person attract what for life?

Korean folklore says a person who sees an otter (sudal) will attract rain clouds for the rest of their life; South Korea designated the Eurasian otter Natural Monument No. 330 in 1982.

According to the Muromachi-era Kagakushū dictionary, an otter that grows old turns into what?

The Kagakushū says an otter that grows old becomes a kappa; in the Hokuriku region, Kii and Shikoku, otters are likewise regarded as a kind of kappa.

Who directed the 1977 TV special Emmet Otter's Jug-Band Christmas?

Jim Henson directed the special, adapted from Russell and Lillian Hoban's 1971 picture book; it was one of the first Muppet productions to use radio-controlled puppets.

Who wrote the original songs for Emmet Otter's Jug-Band Christmas?

Paul Williams wrote the songs, including 'When the River Meets the Sea'; the special was taped in Toronto and premiered on CBC before HBO aired it in 1978.