A rare and "vulnerable" otter was spotted taking a dip in a river in west Suffolk. 

It was spotted swimming in the River Lark in Mildenhall on Sunday afternoon diving underwater for food.

The European otter lives along rivers and lakes as well as estuaries and coasts. They are generally nocturnal which means sightings can be rare. 

Suffolk Wildlife Trust says: "With more and more otters to be found across Suffolk, the chances of spotting one have never been better. 

"But although they have been returning to traditional lowland haunts and even establishing themselves in more urban environments, otters remain vulnerable."

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Earlier this month otters were spotted in Holywells Park in Ipswich and it's believed they were there due to recent flooding. 

In the early 1960s there was a rapid decline of otters throughout Britain and Europe. 

Although populations are recovering the species is still classed as vulnerable as threats including lack of suitable habitats, poor water quality and pollution, roads and disturbance from increased use of waterways still remain. 

Otters are protected by the Wildlife and Countryside Act 1981 meaning it is illegal to kill or remove an otter from the wildlife without a licence or disturb an otter in its resting place.