Quadra Islanders recently received sobering information about the state of our ocean fisheries from Colin Campbell, a scientific advisor to the Sierra Club of BC.

Campbell, with a Ph.D in paleontology and world-wide research experience on marine ecologies, provided historical and global perspectives about our planet’s ecology that is rarely available in traditional media.

By calculating the amount of fossil fuel burned since the beginning of the Industrial Revolution, for example, scientists can calculate that we have added 480 billion tonnes of carbon dioxide to the biosphere. Much of this CO2 has been stored in the world’s oceans — we are presently adding 1 million tonnes per hour as this gas transfers from the atmosphere to the seas. Since CO2 forms carbonic acid in salt water, the oceans are becoming more acidic — a drop in pH from 8.16 to 8.05 has occurred in the last 200 years. We are now close to the threshold where microscopic plants and animals, the biological foundation of the entire ocean ecology, will be unable to form the calcium structures they need to survive.

Campbell also pointed out that paleological studies reveal that only 200 billion tonnes of carbon dioxide in the biosphere accounts for the difference between an ice age or no ice age. With our present level of emissions, we may already be committed to a warming that will eventually melt the 2km thick ice sheets of Greenland, thereby raising the world”s oceans by 6 metres — most of the marine damage would be to corals but almost all coastal cities would be flooded and prime agricultural land would be lost to ocean encroachment and salinization.

As for ocean fisheries, Campbell explained that about 75 percent are overfished, depleted or in collapse. When a new species is targeted by industrial fishing, the capture is so efficient that 80 percent of the stock is gone within 15 years.

Oceans are already showing signs of this overfishing: biomass change such as the proliferation of lower species (jellyfish); evolutionary pressure that produces smaller fish; and ecosystem restructuring where shrimp, for example, have proliferated after the collapse of Newfoundland cod stocks. Unless overfishing is curtailed, Campbell explained, we will soon be encountering “issues of equity” — “who fishes and who eats”. (This is already an issue in BC as wild salmon stocks continue to decline.) Barring other factors, Campbell said, the restoration of most global fisheries could be accomplished by placing one-third of the oceans in no-fishing marine reserves for a century.

Campbell was critical of salmon farming, noting the inefficiency of using 2-20kg of wild fish to produce 1kg of farmed fish, particularly when herbivorous species such as tilapia could be a quality food source without stressing marine ecologies.

As for BC’s wild salmon, Campbell suggested we might consider abandoning an ocean-based fishery and replacing it with an estuary-based fishery. This would allow the specific targeting of specific fish and thereby reduce the capture of endangered stocks that are now inadvertently caught at sea with healthy stocks. Such a change in fishing would also allow for a far more accurate count of returning fish and a more precise management of the resource. This was the system

practiced by the coastal First Nations people who caught considerable fish but achieved sustainable stocks for centuries.

The evening was enlightening but unsettling. However, it was honest and frank. And, as Colin Campbell explained, if we are going to address the growing urgency of our environmental challenges, we need to accurately define them. HIs implicit message was that we already have a fairly clear idea of what is going wrong and what we have to do to address our

environmental problems. What we lack is political will. Clearly, as the evening revealed, he has been doing his work as a scientist. Now he is inviting us to do ours.

Ray Grigg

for Sierra Quadra