Otters are a semi-aquatic mammal and a member of the Mustelid family (the same family as badgers and weasels.) There is only one native species of otter in the UK - the Eurasian otter (Lutra lutra). The Eurasian otter is found in many countries across the world, from Ireland to Asia.
Otters have been either endangered or extinct in nearly all of their native countries, however they are now mostly recovering across Europe. One of the main reasons for their decline was pollution of our rivers and wetlands. Thankfully a lot of the worst river pollution has since been cleaned up, however otters are still slow to return to Sussex and we currently have no known resident otters in the County.
Otters are a flagship wetland species, at the top of the wetland food chain. We know that if otters are healthy, then humans and all the other wetland species in the food chain below them are also healthy. Conservation measures which help otters therefore help a whole range of other species including fish, birds and insects.
An otter needs three important things in order to survive :-
1. A plentiful food supply
2. Clean, unpolluted water
3. Quiet, undisturbed places to rest and breed
Otter dens are called holts (permanent resting places) or hovers (temporary resting places) and are usually found in quiet hollows in the root systems of riverside trees, small rocky caves, pollarded tree crowns, patches of reedbed, old badger setts or dense scrub.
The following useful guides on otters have been produce by Conserving Natura 2000 Rivers :-
- The Ecology of the European Otter
- Monitoring the Otter and
- Otter Breeding Sites, Conservation and Management
What otters eat
Adult otters can eat up to 1 kg of food a day of food which is seasonally abundant. Their favourite snack is Eels (Anguilla anguilla), but they also eat fish, crustaceans (such as crabs and crayfish), amphibians (frogs etc.), molluscs, occasionally small birds and mammals and even slugs and dragonflies.
Current Conservation Status
Under UK law the otter is protected by the Wildlife and Countryside Act 1981 under which it is an offence to kill, injure or knowingly disturb an otter, damage or obstruct an otter holt. The otter is a UK Priority Species.
Current threats to British otters
Pesticides and sheep dip pollution caused the initial decline of the otter but there are still many things which are hindering their recovery. These include:-
- Habitat destruction and fragmentation – meaning otters have to travel large distances to find food, mates and shelter, with many hazards on the way.
- Disturbance by humans and dogs. Otters are shy and nocturnal animals. During the day they need secluded places to rest. If disturbed too often they may suffer from stress.
- Roads and railways. The main cause of otter deaths is roads. In winter when rainfall swells rivers, otters are forced to cross roads to travel from one fragment of habitat to another and they frequently get run over.
- Mink traps, crayfish traps and eel fyke nets are a threat but can be fitted with otter guards.
- Pollution can directly harm otters or can reduce / kill the food available for them to eat.
- Direct persecution is still an issue, despite it being illegal to kill otters.
Otters and Mink
Otters can be easily confused with American mink, but otters are nearly twice the size of mink and are a much lighter chocolate brown colour. They have a distinctive, large creamy patch running down their necks to their underbelly. Their tails are much less fluffy than mink, and their heads are larger with a flatter muzzle. Remember, otters are shy and nocturnal, so if you see something during the day which is not afraid of humans then it is a mink.
Otter spotters pack if you'd like to know the differences between an otter and an mink, or to try your hand at being an Otter Spotter.our free
Otters and Fisheries
Otters have large territories and usually any impact on single fisheries is minimal. However, in some cases, otters may chose to take up residence near your fishery. If you are experiencing losses of fish due to otters then please follow the steps below.
- First, make sure it is an otter and not an American mink
- If you are sure it’s an otter, take a look at our Otters and Stillwater Fisheries Leaflet.
- Contact your local to see if they can help you secure your fishery against otter predation.
Dead or Injured Otters
- Please contact either RSPCA Mallydams Wood 01424 812055 or
- RSPCA Brighton and East Grinstead Branch 01273 554218
If you think you have seen an otter contact the