A new finding that fish feel pain has set off a tortured debate about the ethics of angling

In early October larch trees paint gold on the slopes of the MissionMountains of western Montana and snow edges down from high rocks in waves, like a curtain blowing closed on summer. Men and women wade into the chilling waters of Rock Creek, JockoRiver, Clark Fork and Blackfoot, casting coils of shining line for trout. For these enthusiasts, fly-fishing is a noble endeavor, a sport that borders on the spiritual. After all, it was these waters that gave birth to one of the immortal lines in a long history of fine fishing literature, the opening to Norman Maclean's A River Runs Through It: "In our family, there was no clear line between religion and fly fishing."

But this year new research has sent unsettling ripples across these serene waters. A team of animal biologists in Scotland, led by 29-year-old Lynne Sneddon, has reported that fish feel pain. In a series of experiments, Sneddon and her colleagues injected bee venom and acid into the lips of captive trout. Some of the fish, the team observed, rocked back and forth, rubbing their lips on the gravel beds of their tanks, behaving in ways, said Sneddon, that "fulfill the criteria for animal pain." (The team also identified a set of nerve endings—known as nociceptors——in the trout's lips.)

"The phone never stopped ringing for a week," Sneddon says, after their findings appeared in the April 30 issue of Proceedings of the Royal Society: Biological Sciences, a journal published by the Royal Society, an independent scientific research organization based in London. "I knew the anglers would be quite annoyed, but I didn't think it would have as big an impact as it did." Other articles followed in the New York Times and elsewhere under headlines such as "Anti-anglers fighting hook, line and sinker" and "Confessions of a man who fishes."

People for the Ethical Treatment of Animals (PETA), which has long opposed all forms of fishing, jumped on Sneddon's work as proof of the sport's cruelty. "It has nothing to do with whether fish are cute and cuddly," says William Rivas-Rivas, a PETA spokesman. "Anatomically, physiologically and biologically, these animals have a very complex system that allows them to feel pain."

The idea of fish in pain runs counter to fishing as wholesome family fun. After all, fishing is the way many children are introduced to the marvels of nature; for adults, it's a ticket to rich solitude and balm for the soul. Fishing is "like virtue, a reward to itself," wrote the 17th-century English writer Izaak Walton in The Compleat Angler. In recent years, while pursuits such as hunting, bullfighting and boxing have been shunned as cruel by a growing percentage of the population, fishing has remained widely popular. In the United States, in 2001 (the most recent year for which statistics are available) nearly 35 million people—more than twice the number who hunt—spent $36 billion on sport fishing.

Among fishermen, the news that fishing might be a little less of a virtue and more like torture traveled fast. "The people who fish are a community," says Ian Frazier, an avid fisherman and the author of The Fish's Eye and many other books. "And just like the way a joke can go through a community, that news went through in days."

James Rose, a fisherman and a professor in the University of Wyoming's Department of Zoology and Physiology, wrote a scathing critique of Sneddon's findings, which appeared on the university Web site, claiming that they contained poor methodology and misinterpreted the data. The key to his objections centered around how animals perceive pain. He cited the Seattle-based International Association for the Study of Pain, which defines pain as "an unpleasant sensory and emotional experience associated with actual or potential tissue damage..." And, he said, the signals sent by nociceptors are not in themselves pain.

"Pain is purely a conscious experience," Rose went on. It has a sensory component that's basically information, which tells you what the nature of the injury is, and an emotional component, which is the suffering part, which makes the pain an unpleasant experience. Fish, he said, simply don't have the capability to experience suffering.

Rose compares a fish's reaction to stimulation to the way some quadriplegics respond when their extremities are irritated. "If you were to pinch the hand of a quadriplegic," Rose said, "the hand would pull back, but the person, unless he was watching, wouldn't have any awareness of that stimulation."

Sneddon isn't buying. It's not right "to suggest that only humans and primates experience pain," she says. "[Rose's] definition means that many other animals, including dogs, cats or birds, can't experience pain."

PETA's Rivas-Rivas agrees with Sneddon. "We can't prove whether fish have an emotional experience or not, because they’re not speaking to you. But simply because they don't scream in pain in the way that we understand does not mean that they're not feeling pain."

Sneddon next wants to see if a trout's reaction to bee venom injections is sufficiently severe to prevent it from engaging in other behaviors, such as responding to fear. This line of inquiry will reveal just how strong the pain—or whatever the experience should be called—actually is.

Her work could throw fishing ethics into disarray. For many years people who practiced "catch and release," a kind of fishing in which the quarry is turned loose as gently as possible in order to keep fish populations high, held the sport's moral high ground. But if pain is a consideration, the fisherman who fishes only for food could displace those indulging in wanton cruelty.

Frazier says Sneddon's research doesn't surprise him. "I've seen fish I've released do things that look as if they're hurt. So I've never doubted that they didn't feel it in some real way."

Why, then, does he continue to fish? "The only reason just sounds selfish," he says. "I do it because I feel like it, and because my desire to do it overwhelms my guilt about it." Most people who cast for trout, he says, understand that the hard truth about nature is that what runs through it is a river of blood. "Fishing is one of the few remaining ways we have in this technological, crowded world to maintain a bond with nature."

"The fact that I'm causing pain is never out of my mind," Frazier adds. "I'm not going to say I'll give up fishing, because that's just not going to happen. But I make it part of how I fish. I watch more and fish less."

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