Repelling the alien invaders

Movie stars and top models would turn up at premieres wearing coats made from their silky soft fur Now, in times when the wearing of fur attracts unwelcome attention from many quarters, mink have become better-known for their activities while alive and kicking.

Since their introduction in the UK, predominantly from America, the semi-aquatic, carnivorous mammals have multiplied in considerable numbers to wreak havoc on our native wildlife. Along with the rest of West Yorkshire, Bradford district is now home to thousands of them.

"West Yorkshire has the worst mink problem in the country," says Peter Britton, Bradford Council's countryside officer (wildlife). "This is due to the number of mink fur farms that existed in the region at one time. All have now closed down, but a lot of animals were released."

Only a decade ago, West Yorkshire was home to several mink farms. Adds Mr Britton: "They are an alien species and our native wildlife has no defence against them. They have almost seen off our local population of water voles."

It is estimated that the number of water voles could have declined by up to 90 per cent in recent years due to the explosion in the mink population.

The weasel-like animals are seen most commonly in the Aire Valley, with sightings at Harden Beck, in the rivers Worth and Aire and on the Leeds-Liverpool Canal. "They are very widespread and are highly visible on certain sections of the canal," says Mr Britton, but adds that he does not know of any "substantial colonies" in the district. "If they do exist we would certainly like to know about them," he says.

The creatures are also responsible for the loss of many bankside nesting birds, particularly coots, moorhens and ducks. When mink breed they also steal eggs and bring them back to their young. Also affected are otters, who will not settle in watercourses with large populations of mink.

Bradford Council has put in place an action plan, with traps being placed in key areas and inspected every day. "We have got a big trapping project across the district, and are being helped by people including landowners, anglers and green keepers, as well as staff from other agencies," says Mr Britton. Once caught, the creatures are exterminated.

The numbers trapped are indicative of the scale of the problem, with three traps on one nature reserve catching 61 mink over a period of just 20 months.

Badger baiting and digging out badgers and their young was once a big problem in the Bradford district. But measures introduced over the past decade has seen the crime become far less common.

"Because the known setts are monitored and in some cases covered by surveillance equipment, it is happening less," says Mr Britton. The nature of the crime itself also contributes to the gradual drop in the number of incidents.

"Digging and attacking badger setts is by nature a lengthy process which makes the offenders relatively easy to catch."

The steps taken to protect the sett have been so successful that the badger population has increased dramatically.

"The population is as high as I've ever known it," says Mr Britton. This has given rise to some unwanted countryside management problems, collapsed footpaths being one, as the animals dig underneath. "We are a victim of our own success," he adds.

For many years badgers - protected under the Wildlife & Countryside Act 1981 - have been linked to bovine tuberculosis, but, says Mr Britton, over a period of more than 20 years, during which the countryside service has carried out autopsies and checks on badgers killed on the district's roads, there has been no evidence of it.

With wildlife crimes being very specific, those involved in policing the countryside become familiar with the perpetrators. "When you are working on a patch you know most of the offenders by sight, and if not by name," says Mr Britton.

This familiarity, plus the exchange of information between different agencies and individuals, can help those involved to anticipate and stamp out any problems. "In professional countryside management circles we constantly exchange information. We have the powers to prosecute and work very closely with the police."

"There are no grey areas on countryside crime," says Mr Britton. "It is either legal or illegal. If it is illegal, my instruction is to prosecute in every case."

Unlike badgers, foxes have only limited protection under the 1981 Act, but are protected from abuse and ill-treatment by the Wild Mammals (Protection) Act 1996.

They can be a pest. Says Mr Britton: "The fox can be a considerable menace in several ways. They can take stock - chickens, pets in gardens like rabbits and guinea pigs, even cats, as well as ducks and game birds. If they get into an area of game birds they can cause catastrophic damage."

Householders contact the service if there is seen to be a problem, but often people, both knowingly and unknowingly, attract them by leaving out food, either uncovered or in bin bags.

"Thankfully, people are becoming more educated now and more responsible, and many have stopped feeding them," says Mr Britton. The introduction of wheelie bins has also helped.

Occasionally, an outbreak of diseases such as the parasitic skin disease sarcoptes, or canine, mange can break out among the fox population and can be passed to pets, in particular dogs, and can be transmitted to humans as scabies.

"We had a bad spell in the district a few years ago when dustbins changed to wheelie bins, reducing the food supply."

In such cases, foxes are trapped and humanely killed. "It is very necessary for the health of other foxes and pets in the area, particularly dogs," explains Mr Britton.

The future for wildlife in Bradford, he believes, is rosy, with well-managed habitats ensuring the long-term survival of the indigenous species.

"Bradford has a lot of good partners to work with. We have acquired a few more natural reserves - there are about a dozen along the Aire Valley - and I am looking forward to working there and seeing improvements in the biodiversity."