This week's report on the environmental aftermath of the 1996 Sea Empress oil disaster has thrown a question mark over the value of rehabilitating injured wild animals. The independent panel of scientists concluded that almost none of the rescued oiled seabirds survived washing and return to the wild: 40 per cent died before or during the cleaning process and 97 per cent of those returned to the wild were dead within two months.
Treating each oiled bird costs about pounds 40, and given the report's grim survival figures, it might be supposed that the rehabilitators would now be questioning the theories that underpin their work. Not a bit of it, apparently. "I don't care if it costs pounds 2,000 to put just one bird back into the wild - it's fully justified. These animals are injured for unnatural reasons and it's our duty to try to put right the damage." Graham Cornick, who runs Hydestile Wildlife Hospital, is adamant that money should never be an issue when it comes to rehabilitating wild animals: "We've never put an animal down for financial reasons, ever."
"If you're going to be brutal, it's largely a waste of time," counters Dr Simon Lyster, director-general of the Wildlife Trusts. "Resources should go to something more sustainable - like a nature reserve, or a campaign to persuade farmers to be environmentally sensitive."
These two committed animal lovers clearly have radically different positions. The "welfarist" Cornick believes man's duty is to try to rectify the distortions he creates, while in contrast the "conservationist" Lyster views the grander perspective: "It is difficult to think of any species that would benefit from the return of the occasional individual," he says. "But it is easy to find examples where just a few acres would make a significant difference - for example, 97 per cent of our flower-rich hay meadows have disappeared." The pounds 2,000 that Mr Cornick might spend on one casualty would buy an acre of this.
So what good do our animal rescue centres really do? "Rehabilitation is a drop in the ocean, and will never have any practical impact on our wildlife," says Pauline Kidner, who runs a badger hospital in Somerset. "I do it because I enjoy it, not because I think I'm altering the fate of badgers generally." Likewise, Britain's biggest animal welfare charity, the RSPCA, tries to steer a median line. "Animals are brought in because they're in trouble," says Peter Budd, veterinary manager at the West Hatch hospital. "We patch them up for a second chance where we can, but they've got to be 100 per cent fit if they're going to have any hope at all." As a result, he says, he would put down any amputee: "It's lost its competitive edge, and once back in the wild will fail fairly rapidly."
Jim Chick, chairman of the Hawk Board, which advises the Government on issues affecting British raptors, believes most casualties should either be returned quickly or put down: "There are far too many one-eyed, one- winged birds mouldering away in aviaries," he says. "Most have no quality of life and it would be much more humane to put them down immediately." But in spite of this hard-nosed pragmatism, he has returned hundreds of birds to the wild at considerable personal cost, knowing their chances to be poor. "Nature is brutal, and 75 per cent of young raptors die in their first year anyway. Most birds brought in to me were found because they simply weren't able to cut the mustard. I hope my returnees made it - but however hard I try, I can't change the way things are."
The scriptwriter and animal rights activist Carla Lane, who runs Animal Aid, disagrees violently with what she sees as this heartless line: "We have eight seagulls here which can't fly," she says. "The RSPCA told me to put them down because they would have no quality of life, but we gave them the walled herb garden, with a pond and ladders up to perches. Three years later they're happy and bright-eyed because they can bathe, eat and do everything a seagull normally does except fly." In addition, Animal Aid has pairs of crippled blackbirds and hedgehogs, both of which breed successfully."They learn to live with these problems - there's absolutely no need to put them down," says Lane.
"Most animals live about five times as long in captivity as in the wild; people forget that nature is very brutal," counters Chris Mead, of the British Trust for Ornithology. "What really matters is not how long an animal lives, but whether it is playing its part in the grander scheme of things. The healthy chaffinch I watch from my kitchen window may be food for a sparrowhawk a minute later. But even in death it is boosting the chances that the hawk will raise young successfully. The `happy' captive animal is merely existing; it is not playing its proper part in the food chain."
There are frictions elsewhere. Alien muntjac deer, introduced accidentally at the turn of the century, are now common across southern Britain and cause immense damage in the handful of remaining lowland coppices. The speed of their spread is believed to be due, in part, to well-intentioned rehabilitators releasing casualties into new areas. Similar problems have been reported with squirrels, foxes and even hedgehogs.
Perhaps the worst problems occur with barn owls, however: "Until recently there were real problems with people breeding injured owls and releasing the young," explains Chick. "Not only were virtually all of the youngsters dying without their parents to help them, but those that managed to survive were seriously disrupting the breeding chances of existing pairs." Indeed, the situation became so grave that the law had to be changed to require release schemes to be licensed.
But although many reserves have been badly affected by the consequences of such actions, Dr Lyster says rehabilitation is important: "It would be unconscionable not to do something for an injured animal," he says. "Who knows, the child who nurses a hedgehog back to life may be next the next David Attenborough - and in the long run that could be of immense value to many other species."
Similarly, although Mead's research suggests that only 1 per cent of oiled seabirds survive a return to the wild, he thinks it vital to try: "We should never get into the situation where no one bothers," he says. "The sight of an oil-soaked bird being washed puts enormous pressure on the oil companies to improve their act; just don't fall into the trap of thinking it will help that particular bird."