Abalone diving banned as population plummets
Northern California season closing to protect species
Sport abalone diving in Northern California, a tradition going back generations, will not be allowed next year in the region because biologists say the state’s population is on the brink of collapse.
Thursday’s decision came at a meeting of the California Fish and Game Commission in San Diego after a warning from scientists at the California Department of Fish and Wildlife that the population is in severe decline. The commission voted unanimously to close the fishery for one year, which has not happened since it closed the abalone fishery in the southern part of the state in 1997. The Northern California season would normally be open from April to November.
“There are multiple indications that this fishery is collapsing,” said Cynthia Catton, an environmental scientist for the California Department of Fish and Wildlife. “There’s no sign that it’s even hit the bottom yet. We’re seeing continuing active mortality. We’re seeing continued starvation conditions.”
The decision to close or keep the abalone fishery open has created tensions between state biologists,
along with environmental groups such as Oceana on one side and members of the diving community and the Nature Conservancy on the other. The two sides disagree on the best way to maintain the sea snail’s dwindling population in light of severe environmental conditions, as well as on the best scientific methods to track their population. Divers also worry the move could be permanent.
“They’ve done these temporary closures before, and they’ve never reopened,” said Joshua Russo, president of the diving organization Watermen’s Alliance.
In recent years, kelp forests have been devastated because of changing ocean temperatures and an exploding population of purple sea urchin, which compete with abalone for kelp, upon which both species rely. For red abalone, the lack of kelp has led to starvation, mortality and low reproduction rates. For the same reasons, the 2017 season for sport abalone fishing was reduced by two months and the annual limit was reduced to 12 from 18 per person.
Because abalone take many years to reach reproductive age, “the consequences could last generations,” Catton said.
The abalone fishery south of San Francisco has been closed since 1997 for similar reasons, and the population has not yet recovered enough to reopen. That’s in contrast to the fishery’s heyday in the 1950s and ’60s, when California commercial fishermen brought in about 2,000 metric tons of different species of abalone annually. Commercial fishing was banned in the state in 1997.
In a letter it submitted last month to the Fish and Game Commission, the Nature Conservancy argued to keep the fishery open, offering an alternative way to monitor and manage the population, which it called “a conservative approach to resource management under the recent extreme environmental conditions, thereby ensuring full stock recovery, while still maintaining access to the resource.”
Avid divers such as Jack Likins of Gualala (Mendocino County), who traveled to San Diego to speak at the meeting in favor of keeping the fishery open, argue that the abalone would actually be better protected if the legal fishing remains open in a limited capacity, because poaching would continue.
According to a management plan created 20 years ago, the state must close the fishery when the density of abalone in certain areas drops below a certain level. (The state is in the process of updating that plan.) Catton and a team of fellow scientists based at the UC Davis Bodega Marine Laboratory in Bodega Bay, along with volunteer divers, conduct the surveys each fall.
“It’s hard to describe the emotion that I felt doing the surveys this year. It was just heartbreaking,” she said. “Areas that I remember being lush with kelp, that I remember having to fight the kelp, now it’s bare rock. It’s just bare rock, with countless abalone shells littering the floor.”
In August and September, the divers surveyed the 10 most popular diving sites in Mendocino and Sonoma counties and found abalone at an average of .15 animals per square meter, which they consider half the bare minimum and initiates a closure of the fishery. The density has dropped 65 percent since they conducted a survey last year, Catton said.
Also, Catton observed that the live animals had lost muscle mass, meaning they can’t reliably clamp onto rocks and are vulnerable to predators, including sea urchins and seagulls.
“It’s one of their primary defenses against predation — human predation or otherwise,” she said of a healthy abalone’s foot muscle. “It holds them in place and keeps them from getting washed up onshore with the waves.”
When abalone are starving, their reproductive organs also shrink. Catton also was alarmed that abalone had moved mostly to shallow areas no more than 15 feet deep, she said. Normally a lot of them congregate in the deeper areas that most divers can’t access, which forms a natural protected nursery to keep the population going.
Yet Likins, who dives about 30 times a season, mostly to do volunteer surveys for the nonprofit organizations Reef Check and the Nature Conservancy, said things often look different to him than what the surveys represent. He added that surveys have proved to be problematic based on a peer review of the department’s methods as well as analysis done by the Nature Conservancy.
“The main drawbacks of it basically are that it’s statistically unreliable,” Likins said. “There is so much variation from year to year.” Though the surveys are done at popular diving spots, they don’t account for vast areas of the coast that abalone inhabit, he said.