The full scale of the damage being wreaked upon wildlife and ecosystems by flooding can be revealed today, as conservationists warn that Britain could have an “absolutely devastating environment incident” on its hands.

 

Noxious hydrogen sulphide fumes and lead poisoning are among the threats from floodwater contamination – while animals at almost all stages of the food chain, from insects to small mammals and birds, are already thought to be drowning or dying from lack of food.

 

Hedgehogs, badgers, voles, worms, birds, wood mice and bumblebees – all are said to be perishing, according to experts.

 

Many animals could be poisoned by floodwater redistributing pesticides and toxic chemicals from industrial sites, a new report indicates.

 

The study, published in the journal Science of the Total Environment, links floodplain contamination to lead poisoning in animals for the first time. It found that lead-laden floodwaters were responsible for the death of two young cattle on a West Wales farm in the summer of 2012 by poisoning silage cut from a contaminated field that they consumed.

 

The contaminated material is thought to originate from historical metal mining in the area which was washed downstream from mining sites and lay on the floodplain for years – until rain washed it into the river before it flooded out again downstream. Ecologists say this kind of material can travel hundreds of miles downriver before being washed back on to land.

 

The decline in earthworms could be particularly problematic for the food chain, reducing the food supply for birds such as song thrushes and blackbirds in the spring and summer.

 

The floods are also bringing further misery to two mammals that are already suffering significant population declines – the hedgehog, whose numbers have rapidly diminished in recent years, in part because of habitat loss, and the badger, which has been the subject of trial culls in the flood-hit counties of Gloucestershire and Somerset.