SEATTLE -- The National Marine Fisheries Service has declined to list a prized 6-inch Pacific Ocean marine snail as an endangered or threatened species.
The federal agency announced this week that its status review found that the pinto abalone is not in danger of extinction and does not warrant federal protection under the Endangered Species Act at this time.
Pinto abalone, valued for their delicate flavor and mother-of-pearl shell, are found from Alaska to Baja California.
Two conservation groups petitioned the agency in July 2013 to conduct a status review for pinto abalone.
The mollusks need federal protection because their populations have plummeted from 80 percent to 99 percent in much of their range, according to the Natural Resources Defense Council and the Center for Biological Diversity.
They face threats from historical overfishing, poaching, climate change, ocean acidification and other factors, the groups said.
"It's disappointing," Brad Sewell, a senior attorney for Natural Resources Defense Council, said Friday. He added that he was still reviewing the report but believed the pinto abalone clearly qualified for listing at least as a threatened species.
"These are species that science shows ocean acidification and climate change are going to do it in," he said. "The only way of saving the species is to address the health of the species early on and get it back to robust diverse populations."
A team of experts convened by the agency reviewed factors affecting the mollusks. Based on the best available scientific and commercial information, the federal agency concluded that the marine snail "is not presently in danger of extinction, nor is it likely to become so in the foreseeable future, throughout all or a significant portion of its range."
The shellfish will remain on the agency's "species of concern" list, according to the division of the National Oceanic and Atmospheric Administration.
The finding is to be formally published Monday in the Federal Register.
Conservation groups says pinto abalone have nearly disappeared in Northern California and are declining in Southern California.
Washington never had an authorized commercial fishery and closed its waters to recreational fishing in 1994. Alaska closed its commercial fishery in 1996, though subsistence and personal use fishing continue. Canada prohibited all fishing in 1990.
Pinto abalone are found in scattered intertidal zones — the area between tide marks — and extreme low tides leave them exposed.
It is the dominant species found in Washington, British Columbia and Alaska and is often referred to as the northern abalone.
Alaska Natives use the meat as a supplemental food and trade item, according to the Alaska Department of Fish and Game. The mother-of-pearl interior of the shells decorates carvings and ceremonial dress. Outside coloring can be red, pink, tan or mottled, according to the department.
Poorly regulated commercial harvests in the 1980s and 1990s greatly reduced populations of pinto abalone, according to the conservation groups' petitions.
Natural predators include sea otters, river otters, minks, crabs, sea stars, octopi and wolf eels but the biggest threat is illegal harvest.
Poachers operate in British Columbia and remote areas of Alaska and British Columbia. They target the largest, most highly reproductive mature adults, according to the petitions.
The federal agency said this week that the effects of overfishing have reduced levels of the shellfish. However, they said, pinto abalone populations continue to persist throughout most survey sites.