In The Countryside, Cornwall Today

When it comes to fishing the birds are a hard act to follow but the otter could follow anything, well under water at least.  Slim, sleek and playful the otter is one of Cornwall’s best loved mammals and yet relatively few people have actually seen one in the wild but their cute and cuddly appearance belies a hardy and tenacious nature. 

In Britain there are otters that live in coastal waters and those that live in rivers.  Most of those that live in the sea are found in Scotland and these animals tend to be active by day.  In Cornwall our otters are most common in rivers though they are sometimes found in tidal estuaries and have been seen in the sea but they are nearly always nocturnal.  During the day otters will find a safe location such as amongst the roots of a tree in thick vegetation to lie up and rest, these spots are known as lairs.  The reason for otters choosing to hunt by night is simply to avoid contact with humans, they are a very shy animal, but where it is quiet otters will be found hunting a while before darkness and again at first light.

When on land the otter’s sense of smell is its most important sense and this often warns them of danger, their eye sight is less important but their hearing is good.  When underwater otters use touch as their primary sense, rooting about in the weeds they disturb prey which brush past their whiskers and in a flash the otter has the prey caught in its teeth.  The otter also uses its sight, particularly in clear water, and it has the unusual ability to adjust the shape of the lens in its eye so that it can see clearly underwater and on land. 

Otters are perfectly adapted for swimming with a long flexible body, a strong tail and webbed feet.  Their firm grip is a match for the most slippery of eels and they bring their catch to the surface to devour it.  After a successful fishing expedition otters will snooze and groom amongst riverside vegetation.  Looking after their fur is obviously very important to them since it gives them insulation in fact the otter’s fur has an incredible density with about 50,000 hairs per square centimetre making it exceptionally well insulated. 

Otters seem to be doing very well in Cornwall and the rest of the country.  The crash in their population, which occurred in the 1960’s and 70’s, was due to agricultural chemicals leaching into water courses and killing fish but as soon as this was corrected otters began to recover.  Given their swollen numbers there has never been a better time to try to find otters in Cornwall though this is not an easy task.  The best chance is to find signs of activity during the day and then revisit the location at dusk or dawn.  One of the best clues to look for is their spraint, or faeces, which is often left on obvious stones at the edge of rivers.  When waiting for them to emerge sit quietly and down wind of the location.  Try to find a spot which is visible from a distance.  Probably the best river in Cornwall for otters is the River Camel but all of our substantial rivers have otters.

The only possible confusion species for otter watchers is the mink.  The mink is an American animal that escaped from fur farms in the second half of the 20th century and has established a thriving population.  Distinguishing the mink from the otter is a simple task given reasonable views.  Firstly the mink is much smaller at only around 50cm long it is just half the size of the otter.  Secondly the otter is plain brown with a white throat whereas the mink tends to be dark all over, though it is quite variable.  It was once thought that the reason for the otter’s decline in the 60’s and 70’s was due to the existence of mink but as the otter has re-colonised former haunts the mink has actually declined.  It seems that the otter is more than capable of standing up for itself!

Figures released by the Mammal Society suggest that, across Britain during the period from 1994 to 2004, otter numbers have increased from an estimated 7,300 to 12,900 whereas mink, over the same period, have declined from 110,000 to 37,000.  One reason for the decline in the mink population is that fewer are now being released from captivity than was the case.