PORTLAND — American eels will not be listed under the Endangered Species Act, the U.S. Fish and Wildlife Service said Wednesday, a victory for fishermen of the increasingly valuable species.

The wildlife service rejected a petition from the California-based Center for Environmental Science, Accuracy & Reliability to list the eels — which are prized in Asian cuisine — as threatened.

The petitioners argued that the eels have lost more than 80 percent of their habitat and the security of the stock is jeopardized by fishing pressure from commercial fishing. But the wildlife service told The Associated Press that a report to be issued Wednesday will say that “there have been large declines in abundance from historical times” but “the species currently appears to be stable.”

Fishermen and fishing advocacy groups campaigned against additional protections for eels. Listing them under the Endangered Species Act would have severely limited the ability to harvest them as a commercial species, and they can be of high economic value because of their use in sushi.

Maine baby eels were worth more than $2,100 per pound in 2015, up from less than $100 per pound in 2009. The baby eels, called elvers, are sold to Asian aquaculture companies that raise them to maturity and use them as food.

The service acknowledges that habitat loss and fishing have cut back eel populations in localized areas, but the fish’s challenges do not rise to the level of listing under the Endangered Species Act, said Krishna Gifford, a listings coordinator for the service. The eels’ population is much lower than it was in the 1970s and ’80s after a decline in the ’90s and 2000s, but it appears to have stabilized since, the service said.

“We know these things are not threatening the overall species,” Gifford said. “We know the eels remain widely distributed through their historical range despite habitat loss throughout their range.”

Only Maine and South Carolina fishermen harvest elvers, and South Carolina’s fishery is much smaller. Several other states have fisheries for older eels, including Maryland, Virginia and Delaware.

Their value rarely exceeded $3 million per year from 1950 to 2010, but it ballooned to more than $40 million in 2012, largely because of the growth of Maine’s elver fishery. Value of Maine baby eels has waned somewhat in more recent years, in part due to a quota system and other controls, but it remains far above historical averages.

American eels have become more valuable in recent years largely because of a sharp decline in their population across Europe in the 1990s. The American eels range from Greenland to Venezuela and hatch their young in the Sargasso Sea.

The federal wildlife service also evaluated the eels for listing under the Endangered Species Act in 2007 and declined then, as well.