Otter Species

Otter-like animals have inhabited the earth for the last 30 million years and over the years have undergone subtle changes to the carnivore bodies to exploit the rich aquatic environment.

Otters are members of the Mustelid family which includes badgers, polecats, martens, weasels, stoats and mink.

You can find out more about each of the 13 species below and check out their current conservation status in the Red Data List.

You can find out more about each species in “Otters of the World” available at the Ottershop.

North American River Otter (Lontra canadensis)

SIZE	1 - 1.5m
WEIGHT	10kg
DIET	Mainly fish including kokanee, mountain whitefish, but opportunistic so will also take freshwater mussels, amphibians, birds, crabs, crayfish, frogs, rodents, aquatic insects etc.
GESTATION	9-12 months
OFFSPRING	2-4
CONSERVATION STATUS:	Least Concern CITES Appendix II

Photo: WildARC

This is another otter that has suffered at the hands of man. Originally it was widespread throughout America and Canada, ranging from Alaska to Florida, but it disappeared from most of mid America due to hunting, habitat loss and pollution. Even in 2015 the North American river otter is still trapped for fur in 37 states.

The short, dense fur is dark brown, with the face, chin, and throat having a greyish tinge. The North American otter is long and cylindrical in body shape. It has short legs and a short, thick neck. These otters are largely fish eaters relying on a wide variety of species but they will occasionally take amphibians and reptiles.

These otters mate in late winter and early spring. After mating, a delay of 290-380 days occurs before the actual development of embryos begins. Gestation takes 60-63 days once implantation of the embryos in the uterus occurs. In March or April, from 1-6 young are born in a leaf- and grass-lined holt close to a water source. The young, called cubs or sometimes pups, are developed enough to leave the holt with the female at 10-12 weeks of age.

A North American river otter is capable of breeding once it reaches about two years of age. They have delayed implantation of the embryo in the uterus which makes the gestation period appear very long, ranging from 9-12 months; this delayed implantation is rare in otters although it is common in the mustelid family as a whole.

Besides obviously being found in rivers, these otters also live in lakes, coastal marshes and even rocky sea coasts. They are active both day and night.

Many thousands of otters are killed each year for fur. After their severe decline, otter populations were restored into 21 American states and one Canadian province and in many of these they can now legally be trapped again. The numbers given by government departments do not take into account animals which have not been registered or those which are caught incidentally when trapping for beavers. In December 2015 a teenager out trapping for beavers in Indiana accidentally caught two otters within ten days!

American and Canadian furs are traded at big auction houses in America and Canada and the strongest markets are in China and South Korea. Manufacturing centres exist in central and NE China and South Korea. Buyers come from Beijing, Hong Kong, Japan, Germany, Italy, Greece, Turkey, USA, Canada and the UK.

One argument given to support trapping is that it helps conservation. In the Arizona Hunting Regulations it says: "the North American model of wildlife conservation is the world's most successful ... Hunting and angling are the cornerstones of the North American model of wildlife conservation ..."

So is otter trapping sustainable? If we look at the figures, many states in USA and Canada have no limit on the numbers trapped. In some of the states there simply is no up-to-date information on population status.

When we have queried this we have been told that showing the numbers killed alone has little to do with evaluating the sustainability of “harvests”. Of course this is true but equally if we do not have reliable information on how many otters there are, then no-one can definitely say it IS sustainable. It is stated that populations of river otters have expanded dramatically in the USA over the last 30 years and they are confident that, overall, harvests are being conducted in a sustainable manner. How can this be true if they have no actual data to support this?

Click here to read Paul’s Blog about the American trapping issue

Distribution of the North American River Otter (Lontra canadensis)

Data based on Otters of the World (IOSF 2017) which is available at the Otter shop.