Ocean warming affecting fish populations

WOODS HOLE, Mass., Nov. 3 (UPI) -- U.S. marine scientists say they've discovered about half of 36 fish stocks in the Northwest Atlantic Ocean have been moving northward due to warming waters.

National Oceanic and Atmospheric Administration researchers said the northward shift of the fish populations, many of commercially valuable species, has been ongoing for about four decades, with some stocks nearly disappearing from U.S. waters.

"During the last 40 years, many familiar species have been shifting to the north where ocean waters are cooler, or staying in the same general area, but moving into deeper waters than where they traditionally have been found," said researcher Janet Nye at NOAA's Northeast Fisheries Science Center in Woods Hole, Mass., and the study's lead author. "They all seem to be adapting to changing temperatures and finding places where their chances of survival as a population are greater."

Nye and co-authors Jason Link, Jonathan Hare and William Overholtz said their findings are another example of the need for an ecosystem-based management approach to our fisheries.

"Many factors, temperature among them, influence the status of a fish stock, and we need to be aware of all of those factors and consider them in management decisions," said Link. "Looking at 'the big picture' helps put each piece of the puzzle in perspective."

The study appears in the journal Marine Ecology Progress Series.