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Lingering hope for fresh, buttery crab is slowly melting away as killer toxins disgorged by colossal algae blooms lurk stubbornly offshore, wreaking havoc on the Bay Area fishing industry and raising concerns about the future of the winter staple. High levels of a neurotoxin called domoic acid are still being found in Dungeness crab between Crescent City (Del Norte County) and Monterey almost two months after the poison forced health officials to close the lucrative commercial Dungeness season before it opened, after also halting recreational fishing. The ban, which includes rock crab, was supposed to be temporary, but the microscopic pathogen has remained in the food chain even though the algae plumes that produce the toxin have largely dissipated, biologists said. “We have pretty good evidence the crabs are getting more toxins from the sediments on the sea floor,” said Raphael Kudela, a professor of ocean sciences at UC Santa Cruz. “They are essentially getting reinfected.” Kudela said a late-January opening is possible for Dungeness fishing along the Central and Northern California coast, leaving enough time to salvage at least part of the crabbing season, which officially closes June 30. “It’s slowly, slowly decreasing,” he said of the poison floating around in the ocean, “but it can take several months to get rid of the toxins in their bodies.” “This fleet is starting to get in trouble. They are starting to really hurt,” said Larry Collins, president of the San Francisco-based Crab Boat Owners Association, who has his doubts about a late-January opening. “I’ve been doing this a long time, and I’ve never seen so many bad things stack up.” Domoic acid, which can cause seizures, coma and even death when consumed by marine mammals or humans, has been accumulating in the ocean since April, when the algae started multiplying. The blooms, known as red tides, thrived in warm water off the California coast last summer and fall, and the elevated temperatures are being reinforced by an El Niño weather pattern. The water off the West Coast last summer and fall was as high as 6 degrees warmer than normal. Poisonous tides 40 miles wide were documented through October across California all the way to northern Washington — the biggest collective bloom of toxic algae marine biologists and oceanographers had seen on the Pacific coast. “The bloom basically went away in October,” Kudela said. “We occasionally see a little bit of the algae, but it is at low levels.” The problem, Kudela said, is that the naturally produced poison accumulated in the tissues of many sea creatures that Dungeness crab eat. The spindly crustaceans are both formidable predators and effective scavengers, devouring smaller crabs, sea stars, worms, dead fish and other critters that sink to the bottom or linger in the sediment. It doesn’t help that some sport crabbers used infected anchovies earlier in the year as bait, Kudela said. The commercial crab fishery, which brings in $60 million to $95 million a year, was scheduled to open Nov. 15. It cannot begin until two consecutive samplings, collected at least seven days apart, show safe levels of domoic acid. Levels of 30 parts per million in the viscera and 20 parts per million in the meat of crabs are considered unsafe to eat by the California Department of Public Health. The most recent testing shows that all the crabs in Monterey, 53 percent in San Francisco and Half Moon Bay, and 67 percent in Bodega Bay are above that threshold. Some relief may be on the way. Last week the state lifted its health advisory on Dungeness and rock crab off parts of Santa Barbara and San Luis Obispo counties after tests showed domoic acid had dropped to low or undetectable levels. Officials, though, warned people to rinse off crabs before cooking them, to boil or steam them, and to avoid eating internal organs. Oregon and Washington also reopened commercial crabbing after a monthlong closure. Matt Conens, a spokesman for the California Department of Public Health, said domoic acid levels are lower overall than they were in October and November, when concentrations in Monterey Bay crabs were 10 to 30 times higher than the amount considered toxic. Levels of 240 parts per million were not unusual in the fall. One sample in the Channel Islands, off the Southern California coast, tested at 1,000 parts per million — “definitely the worst we’ve ever seen,” Kudela said. “Conditions across the state are slowly improving,” said Conens. “Sample sets with elevated levels in a particular area are not an indication of the area getting worse.” The persistence of the pathogen has nevertheless ruined dozens of community crab feeds and put the rest of the commercial crabbing season in jeopardy, a scenario that could leave those who make their living off the meaty delicacies virtually destitute. The fishing industry was hoping for a good crabbing season after the ocean salmon fishery tanked, yielding only one-third of the average harvest. Dangerous levels of domoic acid were found in anchovies in 2015, forcing the closure of that fishery. Officials in California, Oregon and Washington also implemented warnings or closures for sardine fishing. There has not been a commercial rock cod season for years off the coast of San Francisco, Collins said, and a strict limit of 834 tons has been put in place for the San Francisco Bay herring run, which opened Sunday and is scheduled to run through March. That is the lowest quota for herring in many seasons, according to the state Department of Fish and Wildlife. Some San Francisco boats may head north or south for crab, but Collins said there’s no substitute for the local catch. “We need at least these fisheries for the smaller boats,” Collins said, “but this year we don’t have anything except maybe starvation. We’re pretty well shut down.” Collins said a shortened season probably won’t make up for the losses, especially given that most crabbers normally pull up their gear and switch to salmon fishing long before the June 30 closing date for crab season. Coastal temperatures have recently been much colder, and, given that domoic acid is organic, it will eventually decay, said Kudela. The question is whether the
