Kingfishers may have been seriously affected by the cold weather
The harsh winter may have had a devastating impact on Britain's wildlife, it has been warned.
British Waterways, which looks after 2,200 miles of the nation's waterways made the comments as it launched its annual wildlife survey.
The organisation is concerned frozen canals and lakes will have cut off the food supply to birds such as the heron and especially the kingfisher.
It is asking the public to spot birds, animals and insects for its survey.
Mark Robinson, British Waterways' national ecology manager, said that although nature was "pretty resilient" to events such as the hard winter, many species would have suffered.
"The good news is that our waterways act as green corridors connecting towns, cities and farmland and providing vital shelter and a winter larder for wildlife struggling to survive."
But he said some species would have been particularly hard hit.
British Waterways says the harsh winter of 1962/1963 killed off between 80% and 90% of kingfishers.
Dr Robinson said: "Frozen water and plummeting temperatures may have significantly reduced kingfisher populations, with the possibility that many lost the battle against the cold.
"It is therefore particularly important for us to monitor what species will need our support over the coming year and we're asking the public to help us do that.
"Now that the weather has warmed up, kingfishers are starting to nest and so now is a great time to see them."
The organisation is raising money to improve the habitats for birds found on the waterways, including providing nesting tunnels for kingfishers and preserving their perches.
Last year the wildlife survey recorded more than 42,500 sightings including almost 300 different species of birds, amphibians, reptiles, insects and mammals.