Although the restriction was recommended by the Pacific Fishery Management Council, the
"The fishery has been under pressure for years to reduce its impact, and it has been very successful doing that," said Michael Milstein, a NOAA fisheries spokesman. "The cap would have imposed a cost on the industry to solve a problem that has already been addressed."
The decision brought immediate criticism from environmental groups that had joined the Pacific Fishery Management Council in an effort to further protect a variety of marine mammals and turtles.
The list included endangered fin, humpback, and sperm whales; short-finned pilot whales and common bottlenose dolphins; as well as endangered leatherback sea turtles, loggerhead sea turtles, olive ridley sea turtles and green sea turtles.
"The Trump administration has declared war on whales, dolphins and turtles off the coast of California," said Todd Steiner, director of the Turtle Island Restoration Network, which is based in Northern California. "This determination will only lead to more potential litigation and legislation involving this fishery. It's not a good sign."
Catherine Kilduff, a senior attorney for the environmental group Center for Biological Diversity, said the action is one of the first by the Trump administration to target protections for threatened species along the Pacific coast.
She noted that the president wants to dismantle other federal programs that protect endangered marine mammals.
The 14-member Pacific Fishery Management Council, which manages fisheries in California, Oregon and Washington, recommended that the federal government adopt the restrictions in 2015.
Under the proposal, if any two endangered whales or sea turtles are killed or seriously hurt within a two-year period, the gill net fishery would be closed for up to two years.
The fishery also would be shut down if any combination of four short-finned pilot whales and bottlenose dolphins were seriously injured or killed within a two-year period.
After the fishery management council recommended the limits to the federal government, Milstein said, NOAA Fisheries studied the proposals and took public comment from people for and against the caps.
The NOAA analysis concluded that the costs of the protections far outweighed the benefits and that the fishing industry had implemented measures that greatly reduced the deaths and injury of protected marine mammals.
The precautions included better training for skippers of fishing boats, sound warnings or pingers attached to fishing nets and wider openings at the top of nets that gave whales, dolphins and turtles a better chance to escape.
NOAA statistics indicate that the deaths and injuries to protected whales declined from more than 50 in 1992 to no more than one or two a year by 2015. During the same period, the numbers for common dolphins steadily declined from almost 400 to only a few.
Meanwhile, the figures show that the deaths and injuries of endangered Pacific leatherback turtles dropped from 17 in 1993 to no more than one a year by 2015.
"We've recognized that the fishery has done a lot to clean up its act," said Milstein, of NOAA.
He added that the Marine Mammals Protection Act and the Endangered Species Act still apply and that protection areas for loggerhead turtles and leatherbacks that are closed to gill-net fishing have been set up off the coasts of Oregon and California.
Kilduff said, however, that protections are still necessary because rare species, such as leatherback turtles, humpback whales and sperm whales, are still being killed and injured in gill nets.
There are so few examples of some species that if gill nets kill even one or two, the overall effect can be devastating, she said.
"Government scientists have said that West Coast fisheries can't catch more than one leatherback every five years," she said. "They estimate that four times that have caught just in the gill-net fishery alone."
Steiner, of the Turtle Island group, argued that the deaths and injuries have dropped mainly because the gill-net fishing fleet in California has declined dramatically.
NOAA figures show that the number of vessels plunged from a high of 129 in 1994 to 20 in 2016.
"The numbers caught per set have not gone down," Steiner said. "The California gill-net fishery kills more marine mammals than all other West Coast fisheries combined."
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