Britain’s most endangered mammal has been discovered thriving in many of Birmingham’s urban watercourses.
A total of 46 sightings of the water vole, immortalised as Ratty in the children’s classic Wind in the Willows, have been recorded in the region during an annual UK-wide wildlife survey of inland waterways.
More than 6,000 members of the public and school groups, who visited the canals during the summer and autumn months, took part in the British Waterways online survey.
However, the organisation’s ecologists were alarmed by 21 sightings of the mink – the water vole’s main predator.
The sighting of mink in the area has reinforced one of the key reasons why vole numbers have declined so dramatically in recent years.
Dr Mark Robinson, national ecology manager for British Waterways, said: "The survey shows that wildlife is alive and well on our waterways.
"Apart from the sightings of water voles, it is particularly encouraging to see so many other species flourishing that are associated with the waterways.
"All the sightings are indicators of thriving waterways. Although there were a good number of water voles spotted, I am very concerned by the sightings of mink.
"In some places the two appear to be living side by side but we know that mink pose a real threat to the endangered water vole."
The survey, carried out over the summer, asked people to pay particular attention to recording the places where they observed a water vole in order to build a picture of where voles live and to help their future conservation.
Water vole numbers in the UK have plunged over the decades from more than seven million in 1989 to barely 900,000 in1996.
But cleaner waterways in Birmingham mean that the water vole has been spotted in places previously uninhabitable because of pollution, abandoned supermarket trolleys and dumped fridges. Canal and other inland waterways are valuable for the creatures as they provide safe corridors across the city. Some have been spotted scurrying around Chinn Brook, Billesley.
In August this year a small army of water voles was released into a stretch of the River Dore in Herefordshire.
A total of 500 water voles were re-introduced in stages along the river by the Game Conservancy Trust, after efforts to improve the waterway as a habitat for the animal. They were released in 50 separate colonies having been kept in large cages and spent time on the bank acclimatising to their new environment.
Dr Robinson said the mammals had small hidden ears, silky brown fur, a blunt nose, short furry tail and could be recognised by the distinctive "plop" sound they make as they enter water from a canal bank.
He said the animals, which feed on vegetation, were very different to rats. Rats, he pointed out, were opportunistic feeders with pointed noses and a long, pink, hairless tail. The survey’s most commonly sighted species were mallards, swans, dragonflies and moorhens.
All results were recorded on the organisation’s website, www.waterscape.com/wildlife.