Science

Fish in the fast lane

A P.E.I. firm wants to market genetically modified salmon

Mark Nichols May 7 2001
Science

Fish in the fast lane

A P.E.I. firm wants to market genetically modified salmon

Mark Nichols May 7 2001

Fish in the fast lane

Science

A P.E.I. firm wants to market genetically modified salmon

Arnold Sutterlin remembers how protests flared 20 years ago when a federally backed pilot project to raise Atlantic salmon in a fish farm was planned in New Brunswick. “There was a terrific hue and cry,” says Sutterlin, a federal government scientist at the time, recalling widespread concerns about disease and potential threats to wild stocks. “But you wont find any wild Atlantic salmon in supermarkets today—they’re all from fish farms and nobody seems to mind.” Now,

Sutterlin is at the centre of a new salmon controversy— this time over a genetically modified fish that could become the first transgenic creature to reach the world’s dinner tables.

Sutterlin manages a hatchery near Fortune, P.E.I., 100 km east of Charlottetown, where hundreds of thousands of genetically modified fish—which grow at two to three times the rate of ordinary species—currendy swim inside tanks. The hatchery’s owner, Aqua Bounty Farms Canada, wants to sell the fast-growing salmon and other transgenic fish to commercial fish farmers. But some environmentalists and scientists say the fish, if they escaped, could pose a grave threat to natural salmon. “There is a risk,” says Michael Koo, a campaigner for Greenpeace Canada, “that the transgenic fish could obliterate the much larger population of wild salmon.”

With the Canadian aquaculture industry earning $600 million a year from the sale of farmed fish and shellfish—and stocks of wild fish dwindling—transgenic fish that reach adult size in a much shorter period could have an obvious appeal. Eager to enter the marketplace, Aqua

Bounty’s American parent, Aqua Bounty Farms Inc. of Waltham, Mass., is seeking approval from the U.S. Federal Drug Administration, a process expected to take at least five years. The company plans to apply to Canadian regulators at a later stage. In the meantime, critics worry that Aqua Bounty’s salmon—which carry genes from two other fish species—could threaten human health and play havoc with marine environments. “We don’t know what the implications may be for human health,” says Lynn Hunter of the Vancouver-based David Suzuki Foundation. “But our biggest concern is the threat to wild fish stocks.”

The fear stems from the fact that farmed fish often find their way out of fish-farm pens and into rivers and oceans. And faster-growing transgenic fish, critics say, might compete so vigorously in the wild that natural salmon stocks could be killed off. Aqua Bounty officials counter that even if they escaped, their fish would be

unable to reproduce because all the transgenic fish raised for the marketplace would be infertile females. Still, Garth Fletcher, a marine biologist at Memorial University in St. John’s, Nfld., and a co-inventor of Aqua Bounty’s transgenic fish, admits that sterilization techniques may not always work. “We’ve never known sterilization to fail,” says Fletcher. “But we can’t say it’s 100-per-cent foolproof.” Meanwhile, other researchers who study transgenic fish have found some evidence that the hybrids might be tough competitors. William Muir, a population geneticist at Purdue University in West Lafayette, Ind., has studied transgenic fish and worked with computer models to see what might happen in the wild. His principal concern is that because they can reproduce at younger ages, fast-growing transgenic fish might soon outnumber natural fish stocks. “From what we know,” says Muir, “I’m concerned that transgenic fish might displace wild fish stocks and even drive them into extinction.”

Bob Devlin, a prominent research scientist who runs a Vancouver laboratory for the federal department of fisheries and oceans, has bred his own transgenic fish, including a fast-growing chinook salmon. If they were released in the wild, his chinooks’ voracious feeding habits might, he thinks, leave wild salmon short of food. On the other hand, says Devlin, the transgenic chinooks have competitive disadvantages—they do not swim as well as natural salmon and are less able to resist disease. Given the contradictory evidence, Devlin thinks laboratory research “may not ever be able to accurately predict the risk transgenic fish will pose in the wild.” And ultimately, that uncertainty could persuade regulators to rule that the controversial transgenics be bred only in tanks well away from the sea, and not in the commercial cages at the ocean’s edge now common in fish farming.

Mark Nichols