A ray of hope on the dark seas
Canadian researchers have been chronicling the decline of the world's fisheries for years yet some remain cautiously optimistic that we may still be able to turn the tide on their fate
|One of the pessimists: Daniel Pauly thinks we are seeing the destruction of key portions of the ocean ecology. Photo: Grace Ong
Economics is known as the dismal science, but with numerous apocalyptic reports on the state of the world's fisheries, one could be forgiven for awarding the gloomy title to fisheries research.
Canada has had a front-row seat to the drama of our depleted oceans with the collapse of the cod stocks off Newfoundland in the early 1990s, shutting down an industry that had thrived for more than 500 years. Our scientists, too, have been at the forefront chronicling the plight of the fisheries.
The late Ransom Myers, an internationally renowned researcher and professor of ocean studies at Dalhousie University, made headlines around the globe in 2003 with a paper in Nature (PDF) that showed commercial fishing in the world's oceans had reduced the number of large fish such as tuna, marlin and sharks by 90 percent in the past 50 years. Many of these species faced extinction, he said, adding, "We are in massive denial."
That gloomy assessment is shared by Daniel Pauly, director of the Fisheries Centre at the University of British Columbia and a well-known critic of international fishing practices. Dr. Pauly is a founder of FishBase, a website with more than 1,500 collaborators where visitors can find essential information on the biology of more than 30,000 species. He has also spearheaded The Sea Around Us project, which has yielded a definitive map of the world's fishing activities.
These comprehensive efforts have left Dr. Pauly convinced that we are seeing the destruction of key portions of the world's ecological network. "It is difficult to maintain an optimistic outlook," he says.
But his viewpoint is far from universal. There are many ocean scientists who remain remarkably upbeat about their work. They acknowledge the obvious problems, such as the wholesale elimination of some fish stocks by an industry that often runs rampant on the high seas. At the same time, however, they emphasize the vast proportions of the ocean, about which we still know far less than other parts of our world. Most of all, when investigators look closely at the significant damage we have inflicted on the ocean environment, they also find equally significant prospects for recovery.
Canada has nurtured a large and influential brain trust dedicated to fisheries. In addition to robust undergraduate and graduate programs at a half-dozen universities, institutions on the Atlantic and Pacific coasts host a number of ambitious new research initiatives. These include the NEPTUNE project at the University of Victoria, an undersea observatory that will use an elaborate array of sensors attached to hundreds of kilometres of fibre-optic cable spread across the seabed to continuously monitor the ocean environment; and the Ocean Tracking Network based at Dalhousie, an international effort to monitor marine life and ocean conditions using electronic tagging technology.
George Rose, who chairs the Fisheries Conservation Group at Memorial University's Marine Institute, argues that the state of the oceans remains as compelling and uplifting a subject as ever. "The only depressing thing at times in dealing with fisheries science in Canada is the perception that it's not important any more," he says.
Dr. Rose resents this attitude, which he encounters frequently even from those who should know better. He remembers having dinner with a group of Ottawa bureaucrats who had to be reminded that Atlantic Canada's fishing industry continues to do more than $4 billion in business every year. He says this perception is common in the wake of the cod fishing moratorium, but is quick to point out that this doesn't mean that all fishing in the region has stopped.
"I think at times it gets a little bit overdone," he complains. "There are good news stories from the fisheries, and not all of the world's fisheries are in as terrible a state as some people would have you believe."
|Boris Worm says over-fishing trends are “dangerous” but not inevitable. Photo: Danny Abriel, Dalhousie University
For example, Dalhousie biologist Boris Worm, who co-authored the 2003 Nature paper with Dr. Myers, points to Georges Bank, a major East Coast fishing ground between Cape Cod and Nova Scotia. After witnessing the demise of Canada's cod fishery, American authorities voiced their concerns that the same thing could happen to Georges Bank, which had been a rich source of cod, halibut, haddock, flounder and scallops.
"They took a drastic measure to stop and reverse this by closing half of Georges Bank," says Dr. Worm, describing how some 17,000 square kilometers of ocean became off limits to fishing vessels in 1994. "And sure enough, some of the key species recovered for the first time in decades."
The World Wildlife Fund reported that, by 2001, one Cape Cod fisherman was marveling at the fact that he only had to go half as far to catch twice as much cod as he did before the closure. Scallops rebounded even more dramatically, achieving up to 14 times their previous population density.
"This was a bold measure, and it was short-term painful," says Dr. Worm. "But even in the medium term, say three to five years, it started generating visible benefits."
He says these results testify to the biological resilience of the ocean, a feature that he and others are still trying to assess. This characteristic appears to depend on the variety and number of species that can be retained within a given region. If such regions can be protected from excessive harvesting, their abundance could very well enrich nearby areas, perhaps providing as much seafood as ever before.
This message was communicated in a paper by Dr. Worm and a number of international collaborators that Science published near the end of 2006. Their work explored the virtues of biodiversity and offered examples like that of Georges Bank.
However, much of the media ignored this positive message and instead focused on the paper's observation that current rates of fishing could lead to a global collapse of species by 2048. That observation wasn't necessarily meant to be an accurate prediction of where we'll be in 40 years, says Dr. Worm, but was more "an illustration of how dangerous current over-fishing trends are."
In fact, Dr. Worm sees nothing inevitable in the future of the world's fisheries. "We're not five minutes before midnight, but the trend is going in a direction that's very concerning for food security, as well as water quality and the overall robustness and resilience of the ecosystem," he says. "According to our analysis, we're 30 percent down that way. Now we must focus on how to reverse that trend on a global scale and rebuild depleted fisheries along with their supporting ecosystems."
|Ron O’Dor poses with a 30-kg squid that will be tagged as part of the Census of Marine Life project.
Nor should the great changes currently taking place in the oceans be regarded as unmitigated disasters, says fellow Dalhousie biologist Ron O'Dor. He suggests that oceans will thrive one way or another - his only caveat being that we might not always be pleased with the outcome.
If you like squid or lobster, he notes, you might be happy. Squid along North America's West Coast are enjoying unprecedented success, both in terms of population size and the geographical area they encompass. Similarly, huge numbers of lobster continue to be taken from East Coast waters, representing an increase that could be linked to a drop in the numbers of larger fish that used to keep this population in check.
"I don't like to talk about ecosystem health, because there are many different healthy ecosystems," he explains. As principal investigator with the Ocean Tracking Network, he has a key role in assessing the various ocean ecosystems that could develop. He is also senior scientist with the Census of Marine Life, coordinating similar contributions from some 2,000 people in 80 countries for the multinational venture based in Washington, D.C.
The sheer scale of activities like the Ocean Tracking Network and the Census of Marine Life indicates just how much we still have to learn about the oceans. Creatures thought to have been lost during earlier geological eras occasionally turn up alive and well, notes Memorial University biologist Richard Haedrich. Such surprising finds might not be grounds for optimism, but he accepts them as a tonic against pessimism. "We don't know a lot about what's out there," he says. "Things could be happening and we don't necessarily know it."