Cover

PUSHING NATURE’S LIMITS

In so many ways, we keep putting unnatural pressures on the environment

SUSAN MCCLELLAND,KEN MACQUEEN,JOHN DEMONT June 2 2003
Cover

PUSHING NATURE’S LIMITS

In so many ways, we keep putting unnatural pressures on the environment

SUSAN MCCLELLAND,KEN MACQUEEN,JOHN DEMONT June 2 2003

PUSHING NATURE’S LIMITS

Cover

In so many ways, we keep putting unnatural pressures on the environment

‘SENTINEL’ SPECIES

They are freaks of the natural world-frogs with four hind legs, limbs coming out of their throats, or with no legs at all. Over the past two decades, these abnormal amphibians have been spotted across North America, including New Brunswick, Quebec, Ontario and the Yukon. Because frogs’ skin absorbs pretty much whatever is in the water or air, scientists see them as a “sentinel” species. “This is an ominous warning that something in the envi-

ronment is horribly wrong,” says Doug Haffner, a University of Windsor biologist. One prime suspect: pesticides, which can weaken the immune systems of some animals or act directly on the growth process. “Frogs’ immune systems,” says Haffner, “are so sensitive that where other animals might appear to be dealing with pesticides, frogs can’t.” He and others say those poisons can leave frogs unable to fight off an aquatic parasite, the trematode. They attach themselves to a tadpole, tunnel under its skin, form cysts, usually where the hind legs are developing, and disrupt growth.

As shocking as the deformities are, frogs have a bigger problem-a threat to their survival. With amphibians and reptiles facing enormous pressures from many man-made sources, it will take determined efforts to recover habitat and lower pollution levels to give them a fighting chance. Of the 11 species that formerly thrived in Ontario’s Point Pelee National Park, for instance, six, including the bullfrog, have disappeared since DDT spraying for mosquitoes in the 1960s. The five remaining species have DDT byproducts in their bodies; it will be hundreds of years before that banned pesticide disappears from the environment.

SUSAN MCCLELLAND

HIGH-RISK ENTERPRISE

Otto Langer worked 32 increasingly frustrating years as a biologist with the fédérai Department of Fisheries and Oceans, concerned with the habitat protection of B.C.’s salmon. He quit 18 months ago. The department, he says, is iocked in an “irresponsible” conflict between its mandate to protect wild fish stocks and its role in “blindly promoting” B.C.’s burgeoning, $391-mi!lion-a-year salmon-farm industry.

Langer signed on as director of marine conservation with the Vancouver-based David Suzuki Foundation, one of many environmental groups claiming that aquaculture threatens the marine environment. “Fish farms appear to be breeding reservoirs for sea lice and for diseases,” says Langer. The WWF-Canada’s Nature Audit draws similar conclusions, also warning that the net cages floating in the sea discharge untreated waste and antibiotics,

allow the escape of fish that are not native to the habitat, and drain the oceans of the small meal-fish that the farms use as feed.

An acrimonious debate over farmed versus wild intensified last September when the B.C. government lifted a seven-year moratorium on fish-farm expansion. The industry argues it has learned from past mistakes. It has reduced the number of escapes, the release of polluting food waste and its level of antibiotic use. B.C. Fisheries Minister John van Dongen concurs, calling the industry “safe and environmentally responsible.” Its controlled expansion, he says, “could generate more than $1 billion in economic activity over the next 10 years.”

The WWF locates aquaculture’s heaviest impacts in the east coast’s Bay of Fundy and the Broughton Archipeiago off northern Vancouver Island-areas that produced almost 90 per cent of Canada’s farmed salmon in 2001. The rivers of the archipelago had a disastrously

low run of wild pink salmon iast year. Environmentalists say migrating fish were fatally infested by sea iice from fish farms; the farmers say many factors cause salmon runs to fluctuate. The WWF wants more research and a national aquaculture act. Langer says the federal government already has tough fishery laws-what it lacks is the will to enforce them.

KEN MACQUEEN

ALL FISHED OUT

Commercially valuable fish species are in decline throughout Canada’s Atlantic and Pacific regions. And as those stocks dwindle, notes WWF-Canada’s Nature Audit, commercial interest in the Arctic fishery will likely grow. Let’s hope we’ve learned some lessons about preservation from the shameful tale of the cod which, according to legend, were so thick off Newfoundland when Jean Cabot encountered them in 1497 that they slowed the ship. Fastforward five centuries to federal Fisheries Minister Robert Thibault’s April announcement that the stocks of northern cod are so depleted that all fishing must stop off Labrador, the northeastern part of the province and in the Gulf of St. Lawrence.

How did it come to this? A March report by the Fisheries Resource Conservation Council, which spurred Ottawa’s actions, said the trouble started in the 1960s, when technological change allowed huge trawlers to plunder the cod’s offshore spawning grounds. While the cod managed to survive in huge numbers through centuries of fishing, that scenario suddenly changed. Landings that had historically been in the range of 150,000 to 200,000

tonnes soared to 800,000 tonnes a year. Somewhere in the late ’80s, fishermen noticed their nets were emptier. In 1992, Ottawa declared a fishing moratorium that threw 40,000 Atlantic Canadians out of work in a bid to bring the cod back.

By the late-1990s it looked like stocks were beginning to rebound, prompting the federal government to reopen the fishery on a limited basis. But the comeback never happenedeven with most of the nets out of the water. FRCC’s scientists cite a range of factors including continued fishing, more seals, low levels of spawning stock and high mortality rates for cod. The upshot: with breeding-age cod fished almost out of existence, even shutting the fishery altogether may not be enough. A fish once so plentiful it could be scooped out of the sea in baskets may never recover. “We are at a great crossroads now,” FRCC chairman Fred Woodman wrote in an open letter to Thibault, “and we will all need courage and conviction to make the changes necessary to rebuild our stocks and our fisheries.” If it’s not already too late. JOHN DEMONT

HONEYBEES IN PERIL

The honeybee arrived in North America with European settlers in the 1600s, and a busy bee it is. Not only is honey-making a $100million-per-year enterprise in Canada, the tiny creature’s pollination efforts contribute to an estimated $1 billion worth of crops. But there may not be enough bees to go around this year. The problem dates back to the early 1980s when honeybees that Paraguay imported from Japan were found to be carrying lethal parasitic mites. The pests quickly spread to bee populations in the U.S. and Canada, where they proved capable of killing off an entire colony of European honeybees in a year. Canada banned the importation of bees from the continental U.S. in 1987, but the parasite, which has become pesticide resistant, keeps spreading. “The entire beekeeping community is in a conundrum trying to figure out how to deal with these mites,” says Mark Winston, a Simon Fraser University biologist and bee expert. With a triple whammy of the plague, severe winters and drought putting some beekeepers across the country out of business, he notes, “there will most likely be a shortage of honeybees for pollination." S.M.

WARMER AND HUNGRIER

1rs 1987, Edmonton scientist ¡an Stirling noticed an odd phenomenon: the polar bears he had been observing for the past 10 years south of Churchill, Man., were losing weight. Stirling, who works with Canada’s Wildlife Service, suspected natural causes, possibly a temporary decrease in the bears’ food supply, largely ringed seals. But the weight loss continued. Today, Churchill’s 1,200 polar bears are 15 per cent lighter than they were 30 years ago. Studies Stirling and his colleagues have conducted over the past two decades now point to global warming as the culprit.

Polar bears eat most of their food in the spring, when they roam the ice in search of seals surfacing through holes for air. But with temperatures in Hudson Bay rising, the ice breaks up about two weeks earlier than it used to, leaving the bears less time to hunt. One side effect of their diminishing weight is that they’re having fewer cubs-mostly twins rather than triplets. Researchers expect they’ll see similar effects elsewhere. “These bears are an indicator,” says Stirling, “of the type of thing that will happen to polar bears in other places as the climate continues to warm.” S.M.

KILLED FOR FOLLOWING THEIR INSTINCTS

Wrenetta Sinclair looked forward to an idyllic life when she moved in 2000 to a farm on Judson Lake, straddling the Canada/U.S. border at Abbotsford, B.C., but it hasn’t turned out that way. Each year, many of the trumpeter swans that spend the winter on the lake die from lead poisoning after ingesting shotgun pellets from the bottom of the lake, left from decades of duck hunting. “My husband and I sometimes kill the dying swans to end their misery,” says Sinclair. “This is not what I want my fourand six-year-old boys to see.”

Heavily hunted at the turn of the past century for its thick down, the trumpeter swan was designated a protected species in 1916. Conservation efforts have bolstered the population to about 16,000 from an all-time low of 77 in 1933. But the birds are attracted to the lethal pellets that they mistake for small stones or grit, which waterfowl eat to aid their digestion. With thousands of birds fataiiy poisoned in Canada each year, the federal government restricted the use of lead shot in 1999. But the threat remains, in the millions of pellets lining lake bottoms across the country.

S.M.

VANISHING PLAINS

They’re the breadbasket of North America, beautiful to behold as the winds rustle grain fields stretching to the horizon. But from southern Alberta and Saskachewan to Wyoming and Nebraska, the vast Northern Great Plains are one of the earth’s most threatened and least protected areas. Almost everywhere, they have been ploughed into crop land. With their habitat gone, indigenous creatures and plants have struggled for survival-more than haif the animals on Canada’s endangered list, including the burrowing owl, bison, swift fox and ferruginous hawk, come from this region.

The scale of the grassland destruction across Canada hit home for WWF biologist Lindsay Rodger in the mid-1990s when she began restoring farm and parkland in Ontario to its original grassy state. “To see the beautiful wildflowers and the tall lush grasses is amazing,” says Rodger. “Then I remember this world is almost gone.” On the Prairies, generations of farmers made great efforts to preserve their environment. But with oil and gas development, urban sprawl and other pressures, “protection for species isn’t there,” Rogers adds. “That region is losing its biodiversity.” S.M.