A conservation group has declared that 21 species of bottom-dwelling fish are sustainable food sources again after recovering from the effects of overfishing off the West Coast.

Types of sole, rockfish and sablefish are among the species that have been shifted from the "avoid" category to "best choice" or "good alternative," Reuters reported.

Rife overfishing in areas off California, Oregon and Washington state reduced various fish species to dangerous population lows, causing the federal government to name West Coast fishing grounds an "economic disaster" in 2000.

The Monterey Bay Aquarium Seafood Watch program, the watchdog group that has upgraded the 21 fish species, credits the fishing grounds' recovery to the establishment of marine protected areas, fishing quota regulations from the government and improvements in monitoring fishing hauls.

"The turnaround in such a short time is unprecedented," said Jennifer Kemmerly, director of the Seafood Watch program.

"Fishermen, federal agencies and our environmental colleagues have put so much effort into groundfish recovery, and now we're seeing the results of their work," she told Reuters.

The group has a Seafood Watch list available online that helps people consume fish in an environmentally conscious manner. The program now puts 84 percent of commercial fish brought in off the West Coast into the sustainable eating category.

"The fishermen deserve a lot of credit," said Frank Lockhart, with the National Marine Fisheries Service's groundfish program, as quoted by the Seattle Times. "I still sometimes can't believe how talented they are at avoiding the wrong fish and catching the right fish."

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