English otters back from brink of extinction

A report by the Environment Agency showed that a ban on these toxic pesticides and an improvement in water quality in rivers across England has enabled the mammal to avoid extinction.

The fifth otter survey of England looked at over 3,000 river sites around England between July 2009 and March 2010, and showed a ten-fold increase from 30 years ago in the number of places where there was evidence of otters.

East Anglia and the River Thames showed the biggest increase since the last study in 2002, with rivers and the South West and the River Wye believed to be supporting the maximum number of otters possible. Rivers in areas such as Northumbria, Cumbria and the upper Severn are also thought to be close to capacity.

But recovery has been slowest in the South East – Kent is the only county in England not to have seen otters return already, the survey found, but the Environment Agency believes that otters will spread to the county in the next 10 years. They also predict that the population will fully recover across England in less than two decades.

Much of the improvement to rivers is the result of changes in farming practices, including the banning of chemical pesticides which polluted rivers and harmed wildlife, according to conservation experts.

Conservation success
According to Fran Southgate, wetland landscapes officer for Sussex Wildlife Trust, the chemicals suppressed the otters’ immune systems, affected their eyesight and ability to breed and reduced their food sources – mainly fish and other aquatic animals.

Fertilisers washing off fields and dumping too many nutrients in rivers also polluted water courses – while in more built-up areas such as the South East, run-off from highways has been a problem.

But a lot of work has gone into improving water quality, including farming measures such as margins along the side of rivers to stop run-off which have made things better for wildlife.

Ms Southgate also believes that how rivers have been managed has also had an impact.

River habitats need to be managed in such a way that they provide places for fish and other species such as frogs, crustaceans, mussels, slugs and dragonflies which can all be food sources for otters.

Many rivers have been stripped of the natural features that would have surrounded them, such as wet woodland, reedbeds and scrub to hide in and old or pollarded trees to provide holts.

“For an otter, if they’re breeding, they need a quiet place they can train the young to swim and catch fish.

“They stay with the mother for about a year and they need an undisturbed, quiet, good area of habitat to get successful breeding,” Ms Southgate said.

Food chain
Paul Raven, head of conservation and ecology at the Environment Agency, said: “The otter is at the top of the food chain and, as such, is an important indicator of the health of English rivers.

“The recovery of otters from near-extinction shows how far we’ve come in controlling pollution and improving water quality.

“Rivers in England are the healthiest for over 20 years, and otters, salmon and other wildlife are returning to many rivers for the first time since the Industrial Revolution.

“But there is still work to be done, and we will continue to work with farmers, businesses and water companies to reduce pollution and improve water quality even further, to ensure the full recovery of the otter across the country.”