Feeding down the food web does not always mean that we begin to harvest less desirable species. West coast anglers intensifying their efforts to catch halibut because coho salmon fishing has been banned, or east coast anglers switching from Atlantic salmon to brook trout, are examples of shifts in emphasis, not in quality, but have the same effect – generating additional pressure on resources that have not previously had to sustain heavier harvest rates.

When you consider man’s omnivorous nature, feeding down the web is almost guaranteed to have dire consequences. In Canadian waters, we harvest virtually every species of fish that is large enough to eat or grind up for fish-food or fertilizer. We harvest various species of crabs, barnacles, shrimp, prawns, clams, oysters, mussels, limpets, sea urchins, sea cucumbers, sharks, squid, octopus and seals, and would kill whales too if there were enough of them left to warrant it. We even harvest several species of sea weed.

The list goes on and on, and here’s where we run into real trouble.

Not just in Canadian waters, but around the world, fishing for krill (small shrimp-like crustaceans) is intensifying, both to provide protein for people but also to provide protein for the aquaculture industry. Likewise, harvesting bait fish such as capelin, herring, anchovy and sardines has drastically increased, again to provide both food for man and to provide feed for fish farms.