Friday, February 18, 2011

Fishery science turned upside down

Keep the little ones? That's heresy for most fishery scientists. Don't worry about bycatch? Crazy advice.

But there's an argument to be made for catching fish in proportion to their abundance in the ocean. This goes against the dogma that says selective fishing is best.

A new study says some non-regulated African fisheries are operating in a useful way by failing to select certain fish for catch. The result is a more productive ecosystem despite intense fishing pressure:

"(in some)...specific artisanal and rather unmanaged fisheries of Africa, the use of a wide range of versatile fishing methods and mesh sizes, each of which selects specific sections of a fish community, resulting in a very broad distribution of the fishing pressure on the ecosystem components, leads to high yields while maintaining the ecosystem structure, i.e., the proportions between the abundance of the different size groups. Such “unregulated”, broadly targeted adaptive fishing patterns appear to be far more effective in conserving the ecosystem than single-species management theory predicts. This pattern of development appears to be the result of strong competition between fishers and low individual catch rates, and could be considered analogous to natural predator niche specialization and co-evolution. This requires, obviously, that fishing pressure (using “low tech” gears) remains at levels compatible with the ecosystem productivity."


ElOceanografo said...

What's the reference on this? I'd be interested to read it...

Christine said...

Where is this quote from?

Mark Powell said...

Sorry to leave out the reference. Here it is:

See page 9 for this quote.