Climatide

Olga Caprotti / Flickr

Last January started with announcement by the outgoing head of federal fisheries science, Steve Murawski, that 2011 would be the year overfishing was ended in U.S. waters. What he actually meant was that 2011 was supposed to be the year by which sustainable, science-based catch limits were set for each and every fishery taking place primarily in U.S. waters.

So did it happen? WaPo’s Juliet Eilperin reports federal fishery managers are close.

Although NOAA didn’t meet the law’s Dec. 31 deadline – it has finished 40 of the 46 fishery management plans that cover all federally managed stocks – officials said they are confident that they will have annual catch limits in place by the time the 2012 fishing year begins for all species. (The timing varies depending on the fish, with some seasons starting May 1 or later.) Some fish, such as mahi mahi and the prize game fish wahoo in the southeast Atlantic, will have catch limits for the first time.

Having science-based catch limits for all U.S. fisheries will be a world first – an undeniably historic milestone worth celebrating. But before we get carried away with champagne and confetti, it’s worth remembering that catch limits aren’t necessarily a guarantee of no overfishing, even if everybody stays within the limits. After all, science-based catch limits are only as good as the science upon which they’re based.

The science of counting fish is notoriously difficult. I recently saw it described as being just like counting trees, except that you can’t see the trees and they’re constantly moving. And it gets worse. Based on the number and size of fish around today (coupled with knowledge about growth and reproduction), scientists have to estimate how many and what sizes of fish will be available for harvest in future years.

Even when done as well as humanly possible, stock assessments are tricky – and the scientists who produce them are the first to admit that. That’s why federal officials will continue to list 40 stocks as actively overfished until new assessments confirm that current catch limits are actually appropriate. That’s why Gulf of Maine cod has been added back to the ranks of the overfished, even though the fishery has been operating within its catch limits. And that’s why scientists are constantly working to develop newer and better technologies for counting fish.

In reality, establishing catch limits for all U.S. stocks is neither the end nor the beginning of anything. It is simply one more step along the way to sustainable fisheries.