MONTEREY — With the higher number of humpback whales descending on Central Coast waters, and out of concern with them becoming entangled in crab lines, state officials said this week that they will close the Dungeness crab season on June 1, four weeks early.
The California Department of Fish and Wildlife, which regulates the state’s crab fishery, issued the decision Tuesday following agency Director Charlton Bonham’s assessment of entanglement risk to humpback whales and critically endangered leatherback sea turtles.
The closure will begin statewide at noon on June 1.
“It has been a very difficult year for many in our fishing communities and I recognize that every day of lost fishing further impacts families and small businesses,” Bonham said in a statement.
He added that he wants to continue working with the industry and environmental groups that are part of the Crab Fishing Gear Working Group to minimize entanglement risk while maintaining a vibrant crab fishing industry in the state.
Estimates of the size of the crabbing industry in California vary, but the consensus is that it represents somewhere between $50 million and $100 million annually. It can fluctuate from year to year depending on the length of the season and the per-pound market rate for the catches.
Whales are also part of the Monterey Bay economy with a large number of whale watching boats catering to the influx of tourists each year.
The working group comprises a number of interests, including the commercial fishing industry, environmental groups, scientists, and state and federal agencies. The intent is to work collaboratively to discover ways of reducing entanglement risks while ensuring the livelihood of crabbers up and down the coast.
Ryan Bartling, senior environmental scientist with Fish and Wildlife, said Thursday that the determination is based on assessments made by agency staff on the number of whales moving into certain zones along the coast. Basically, the more whales the greater risk of entanglement.
The Central Coast is in a critical fishing zone (Fish and Wildlife’s Zone 7) that runs roughly from Point Arena to Monterey.
“The director looked at a number of factors, including the number of animals in a fishing zone,” Bartling said. “The number (of whales) in Monterey Bay exceeded the trigger point.”
The science is multi-faceted but generally, climate change is affecting the food supply for humpbacks, mostly krill, where the whales have historically fed farther out to sea. But the warmer water and its lack of nutrients have depleted the krill population, sending whales closer to shore to feed on anchovies, which sets them up to become tangled in crab lines.
Crab traps rest on the ocean floor near shore and are connected to buoys by long ropes. Fishermen check the crab pots by locating their buoys and hauling them aboard via the ropes.
As whales chase anchovies closer to shore they can become entangled in those crab lines. In some cases, the lines cut into the whale’s flesh that then becomes infected and can lead to death. In other cases when the lines are caught in the mouths of whales — they are opening their mouths to feed — they can affect the whale’s ability to feed and in extreme cases can lead to starvation.
Dr. Jarrod Santora, a researcher who splits time between UC Santa Cruz and the National Oceanic and Atmospheric Administration’s Southwest Fisheries Science Center, said in an interview with the Monterey Herald last year that an ocean warming event in 2014-2016 created a dynamic that pushed hungry whales into close proximity to crab gear, causing a 400% increase in humpback entanglements.
While the 2014 warming event is considered an anomaly, Santora warned that it is one that will likely repeat more frequently as water temperatures in the North Pacific warm.
“It’s not a question of if, rather a matter of when we will see this in the future,” Santora said.
Ben Platt, the president of the California Coast Crab Association, on Thursday questioned how many whales are actually coming in close enough to become entangled in crab lines. He said the association represents some 550 boats up and down the coast and they are reporting that the humpbacks are staying offshore with healthy krill populations.
“This closure will be a big hit to those that are counting on the normal crab season for their livelihoods,” said Platt, a second-generation crab fisherman from Crescent City. “The closure seemed arbitrary, and there was no reason to close it early. They are taking extremely cautious measures because they don’t want to take the chance of even one entanglement.”
Dr. Geoff Shester, a senior scientist with the nonprofit environmental group Oceana and a member of the Department of Fish and Wildlife’s working group, said the season closures are having a positive impact on entanglements.
“The new system of time and area closures is working; there have been no confirmed whale or sea turtle entanglements in California commercial Dungeness crab gear this season,” Chester said in an emailed statement. “We commend the Department of Fish and Wildlife for collecting and acting on real-time data showing when and where whales have returned to feed.”
There have been no entanglements reported during this crab season that began in November, compared to 22 entanglements in 2016.
The leatherback sea turtles Shester referenced are extremely endangered and migrate all the way across the Pacific Ocean from their nesting grounds in Indonesia. There, the turtles are losing habitat to development as well as their numbers being threatened by a market for their eggs. The turtles travel to the coast of California to feed, including the Monterey Bay National Marine Sanctuary.
Platt, the crabbing association chief, said the industry is taking strong measures to prevent entanglements, such as making sure none of their boats leave “ghost lines” or unused equipment that have drifted away from their fishing areas untended.
There has been ongoing research into crab pots that have no buoy-to-pot ropes. Instead, the ropes are coiled next to the pot and a signal from the boat releases a buoy that then surfaces for the boat to haul in.
Platt said those technologies, when they do work, are cost-prohibitive.
Contributed by local news sources