Regulations for recreational red abalone diving have been mostly uniform along the Northern California coast for a decade, but the state is now considering changes to allow more locally specific rules.

Through an online survey, the California Department of Fish and Wildlife is asking divers for input about how the red abalone fishery should be managed. The department says tightening rules about when and where divers can fish could increase the likelihood of catching more abalone, while expanding diving opportunities could make it more difficult to find the mollusk. Changes could include stricter rules at some sites and more lax rules at others, based on local populations. But finely tuned regulations would also be more expensive to enforce, likely costing divers more in fees.

The survey responses and comments from public meetings held last fall will inform a forthcoming fishery management plan for red abalone, a brick red to pink-shelled mollusk that is the largest of all abalone species. (The world record is around 12.3 inches long.)

Rules for red abalone diving —such as a ban on scuba gear, annual and daily catch limits and seasonal closures—have been dictated by the state’s Abalone Recovery and Management Plan. The decade-old document outlines management and recovery efforts for all species; two kinds, white and black abalone, are endangered. But the department is developing a specific plan for red abalone, which is the only one with a robust enough population for a recreational fishery. 

In California, red abalone can only be fished north of the San Francisco Bay. Divers are subject to a number of regulations; for instance, they must carry a measuring device on them while diving, so they don’t take abalone under seven inches.

Of the roughly 256,000 taken legally every year along the Northern California coast, most—about 95 percent—comes from Sonoma and Mendocino Counties. There isn’t as much easy public access in Marin, and one avid diver from Point Reyes Station, Billy Wessner, said sedimentation in the county’s waters also makes the mollusk even more difficult to find. Still, over 3,000 are taken from Marin every year, according to state figures.

“There’s still plenty here. It’s alive and well,” Mr. Wessner said.

A combination of overfishing, bad management, disease and predation spurred a massive decline of abalone stocks in the 20th century. And abalone are slow growers: it can take a decade or more for one to reach seven inches in diameter, the minimum size divers can take, making recovery a slow process. 

The state Fish and Game Commission started banning the take of certain abalone species in 1993, and banned all abalone fishing, both commercial and recreational, south of San Francisco Bay in 1997. (Commercial abalone fishing north of the bay had only been permitted for a few years during World War II.) 

The recovery and management plan originally allowed recreational divers to take up to 24 abalone a year. The plan includes triggers to reduce allowed catches, or to close diving sites, if abalone densities fall below certain limits. 

Density is a critical measure of abalone stocks because the relatively stationary mollusk reproduces by shooting sperm and eggs into the water, in hopes the reproductive material will reach a mate. “If they are further than four or five meters apart, the eggs have a low probability of fertilization,” said Laura Rogers-Bennett, an abalone researcher and senior biologist with the department who is based at the Bodega Bay Marine Laboratory.

In recent years, Fish and Wildlife has reduced catch limits in Marin and Sonoma, and closed off Fort Ross, a popular diving site in Sonoma, because of plummeting populations.

In 2011, densities near Fort Ross, one of the most popular and heavily fished sites, were already on a downward trend when an algal bloom in the area depleted oxygen in the ocean and killed thousands of abalone. A comparison of data from Sonoma found that densities fell 60 percent after the red tide. Mendocino, the other heavily fished county, experienced only a slight decline in the same time frame.

Because densities dropped below a certain threshold at a selection of sites used by the state to assess the fishery’s health, the annual take limit was reduced in 2014 to 18 annually. And based on the differences between Sonoma and Mendocino data, the agency effectively divvied the state into two sections: divers could only take nine of those 18 from Marin and Sonoma.

There is little to no information about the effect of the red tide event in Marin, said Ian Taniguchi, a senior environmental scientist with Fish and Wildlife.

But the county was included in the catch reduction to create a simple geographic boundary that is easier for divers to understand and wildlife officers to enforce. And, he added, the department wanted to ensure that divers shifted their efforts north to Mendocino, where they knew densities were robust enough to handle increased take.

Mr. Wessner said he remembers when the annual catch was 100 abalone. But the stricter limits are fine with him. “It makes me strive to get bigger ones,” he said. Some days when he dives, he added, he doesn’t take any. “I’d go dive and look around and I’d only take if there’s a bunch of them,” he said.

Ido Yoshimoto, an artist and arborist who also lives in Point Reyes and has been diving for several years, said the recent limit instituted in Marin, his main hunting grounds, forced him to drive north last year. 

The abalone diving season runs from April to November (with a month-long break in July); if a diver takes the daily limit of three abalone, it leaves one with just three dives during the six-month season. The new limit, he said, “was kind of a bummer, because I love to go here; it’s where I live. To get in the car and drive two hours north to go diving—the conditions are beautiful [up there], so it’s great, but it’s also where everyone goes.”

For Mr. Yoshimoto, diving is not just about dining on abalone—which he prepares simply to let the taste shine through, sometimes panfrying in butter or perhaps grilling after a quick marinade in garlic and olive oil. It’s also about immersing himself in the water and exploring the ocean. “It feels like you’re de-evolving, because you’re slithering into the ocean and it’s kind of awkward at first, when you have flippers on and you’re crawling over rocks and the waves are breaking on you. Then you get in the water, and it feels strangely natural,” he said.

The online survey, which will run through March 6, is meant to help Fish and Wildlife examine the pros and cons of different management methods. It includes questions about a lottery system for heavily fished sites or the entire coast and changing the minimum size limit, the latter of which Mr. Wessner said he supports. “If they raise the minimum size, I think that would be good too, because that would make people have to try a little harder and those little guys could get bigger,” he said.

The survey also asks whether divers would support different rules at different areas. Currently, Fish and Wildlife has divided the coast into over 50 sites, so that divers can report where exactly they pluck abalone from the ocean or rocky shorelines. Except for the catch limits in Marin and Sonoma and the Fort Ross closure, they are all managed the same way.

“One of the big things we’re hearing from our constituency is that they’d rather see something like locally based management, as opposed to management and regulation changes affecting the whole fishery range,” Mr. Taniguchi said.

How specific that management might be is still up in the air. The department, he said, has to balance the desires of divers with what the state can feasibly monitor and manage. Keeping track of more and more sub-populations, and enforcing more complex regulations, will inevitably come with a higher price tag. All recreational fishers need a general fishing license, which is about $50; divers also need an abalone report card, which cost divers $22.17 last year. Right now those cards bring in somewhere around $500,000 a year, Mr. Taniguchi said—money used to enforce regulations and aid in recovery efforts.

The department could also institute a progressive system, in which divers pay more to take more abalone. 

Research being undertaken by Fish and Wildlife could also inform future management. Ms. Rogers-Bennett, for instance, said the agency has been surveying baby abalone—some just a few millimeters long. It wanted to figure out whether there were significant annual differences in young populations. “What we’ve been finding is that we do have big differences. We are seeing good and bad recruitment years. It suggests that we may have year classes that are either very good, average or below average.” It’s another level of information that could help the state evaluate future regulations. 

As far as Mr. Wessner is concerned, he’s fairly pleased with how the abalone are managed now. He caught the 18-abalone limit last year. But, he added, “I’ll do whatever they want me to do, because I want the sport to be open… so future generations can see what a beautiful thing we have on the West Coast.” That future includes his 12-year-old son, with whom he hopes to dive soon.


To take the survey, visit