A big increase has been reported in sightings of the water vole. British Waterways said 89 had been spotted on rivers and canals this year, twice as many as last year. Most sightings of the UK’s fastest declining mammal were on the Kennet and Avon Canal between Reading and Bath.

The water vole, immortalised as Ratty in The Wind in the Willows, joins almost 300 species of birds, amphibians, reptiles, insects and other mammals recorded in British Waterways’ annual survey of wildlife.

Rare butterflies, otters and a porpoise were among the less common of the 42,500 sightings. British Waterways said that it had been a good year for the bumblebee.

A warm start to summer meant that a healthy number were spotted taking advantage of waterside flowers.There were many sightings of kingfishers, the presence of which is considered a sign of good water quality and a healthy ecosystem.

Mark Robinson, British Waterways’ national ecology manager, said: “Canals and rivers are ideal wildlife corridors that support a vast array of wildlife, including bats, newts and otters.

“Whether you are in the middle of a city, or somewhere more remote, you are almost guaranteed to see some exciting wildlife on the waterway. If you look a little harder you might even see something rare or unusual.

“It is particularly encouraging to note the number of water voles spotted this year. Each record helps us to monitor, protect and preserve the amazing biodiversity found on our waterways.”

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