Fish and Chips

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Fishing (be it wild catch or farmed) feeds one billion people around the world.  Actually, it feeds more than that, but those one billion people depend on fish as their primary source of protein.  Unfortunately for the fish, we've gotten a lot better at catching them, leading to overfishing of the more desirable types.  A new project plans to track fish around the world, using implanted tags and seabed sensors. The intention? To understand how fish travel and to improve fishing practices and management.

Fishing Down the Food Chain

To help put the fish situation in perspective, take a look at this page from the Earth Policy Institute. As fishermen have gotten better at fishing and finding fish (bigger and better nets, better boats, fishing in deeper waters, and so on) and as the global population has grown, overfishing of the most desirable types of fish (resulting in the collapse of those populations) has led to fishermen moving down the food chain.

Take cod, for example. Cod used to be very big business. Vast quantities of cod were caught and eaten and the fishing of same, off the New England coast and Canada, was an important industry. Note my use of "was." The Canadian cod fisheries closed in 1992. Consider that the cod fisheries off southern Labrador and Newfoundland yielded an estimated annual catch of 250,000 tons for more than 100 years before the mid-1950s. Now, the numbers of wild cod out in the ocean may be so low that the population can never fully recover.

On the Menu?

Scientists are using seafood prices on restaurant menus from as far back as the 1860s to track the impact of over-fishing. Researchers compared the retail prices from the menus with records from the National Fisheries Service records of seafood landings and their dollar value. Once a marine species became scarcer, its price on the menu went up.

Now, modern technology is stepping in on the side of the fish. To better manage fishing and fisheries, you have to understand what the fish do and how they move through their aquatic ecosystem. A recent story on the CBC News Web site explains the project, which is part of the Census of Marine Life.  Seabed acoustic receivers on the ocean floor, ringing the continents, will interact with the acoustic tags implanted in the fish to track and record how the fish move. With luck (and some regulatory backbone around the globe) the goal of sustainable fishing can be achieved.

As the Census of Marine Life is showing, we have a very poor understanding of what's happening in our oceans and what lifeforms exist there. And when we're relying on those lifeforms to keep us alive, it behooves us to pay more attention to what we're doing.  We've gotten away with being ignorant for a long time.  Let's try being smart for a change.