Red king/blue king: why crab enhancement is so important to Alaska.

What is it about "king crab" that is so evocative of Alaska? Glorious history. Images of king crab bring up largess, days that we thought would never end, mountains of crab bringing a double bounty of food and income from Southeast to the Bering Sea.

But the glory days of a crew making more than $100,000 in a season and boat owners making millions of dollars are gone. While some species of crab are still abundant in Alaska, and there continues to be a red king fishery in Bristol Bay and Southeast Alaska, the giant red kings (Paralithodes camtschaticus) of Kodiak (that once grew to 20 pounds with more than 6-foot leg spans) and the blue kings (P. platypus) of the Pribilof Islands have long been closed to commercial fishing, victims of debated causes.

There is hope, however, that current research regarding the potential to enhance wild stocks through the cultivation of early stage crab juveniles released into the wild might bring those days back.

WHY STOCKS ARE DEPLETED

First, it is important to try to understand why the stocks have not rebounded. There is much speculation about what may have caused such dramatic crashes but few answers. A renowned crab scientist, Dr. Gordon Kruse (University of Alaska Fairbanks), said in a recent interview, "We've been working on rebuilding red king crab stocks for almost 25 years by closing commercial fishing and creating protection zones. We don't have much to show. Grants from the North Pacific Research Board and the Alaska Sea Grant are now enabling us to review stock-reconstruction data on population dynamics since the mid-1950s. Bill Bechtol, a graduate student, is seeking to provide an analysis of that data which could illustrate the relationship of stock fluctuations to a variety of factors, including water temperate, fishing effort, and predation."

TEMPERATURE COUNTS

Kruse thinks a perhaps overdue decadal climate shift of 1 to 2 degrees C cooler might provide more optimal survival conditions as crab are very sensitive to water temperatures. But, he said, predators like halibut, sculpin, Pacific cod, arrowtooth flounder and even salmon could be real culprits in keeping crab recruitment low. In Southeast Alaska, sea otters have a major impact. In a 1999 radio interview, Branden Kelly, a UAF marine scientist, reported "Sea otters are loved by tourists and others because they are incredibly cute. But beneath that cuddly fur coat lurks an insatiable appetite for crab, abalone, sea urchins and other marine life."

As a potential solution to predation, Dr. Kruse notes, "We need to consider habitat measures that would provide hideouts for juvenile crab. A fellow scientist, Braxton Dew (NMFS), found that dock pilings in Kodiak held a potential for creating an enhancement environment."

WHY REBUILD STOCKS?

Why put this kind of effort into rebuilding stocks? Because it can provide a lucrative resource for commercial, sport and subsistence use. Of the 10 species of crab caught all over Alaska, (seven with commercial importance--red king, blue king, golden king, Tanner crab (bairdi), snow crab (opilio), hair crab and Dungeness crab; and three minor species--scarlet king, grooved Tanner and Triangle Tanner), the red and blue king crab have the greatest history of commercial value.

According to the Alaska Department of Fish and Game, "historically, the red king crab fishery has been Alaska's top shellfish fishery. Since statehood in 1959, U.S. fishers have harvested nearly 2 billion pounds of red king crab worth $1.6 billion from Alaska waters, making red king crabs the second most valuable species, next to salmon, to fishers during this period." The Kodiak Chamber of Commerce states, "In 1950, 60,000 pounds of king crab were landed. The king crab fishery became a major force in Kodiak's economy from 1950 to 1959 as the catch increased from 60,000 to 21 million pounds." Alaska Sea Grant notes that "in 1965, fishermen caught 94 million pounds of crab in the Kodiak area, worth $12.2 million, and, in 1981, 14 million pounds of blue king were caught in the Pribilofs and St. Matthew Islands, worth about $10 million. In 1968, the City of Kodiak became the largest fishing port in the United States in terms of ex-vessel value." There were many thriving "crab towns" during the red king heydays.

AFTER THE HEYDAY

Then everything went to pot. The 1982 to 1983 Kodiak king crab harvest of 8.7 million pounds was the lowest in 24 years, followed by a closure of the fishery. Blue king crab around the Pribilof Islands, while smaller than the red king, had been an important source of income for the fishermen of the area. Since 1999, the commercial fishery has been closed due to low stock abundance.

Can enhancement be a solution? In 2004, a casual conversation triggered a way to connect the dots between interested parties. Heather McCarty (contracting to Central Bering Sea Fisherman's Association), Arni Thompson (Alaska Crab Coalition), and myself (Gulf of Alaska Coastal Communities Coalition), all members of the North Pacific Research Board Advisory Panel, discussed a report that Norway was enticing boats from Seattle to harvest thousands of red king crab considered a "nuisance" in the Barents Sea. Those kings were the offspring of Russian Kamchatka transplants more than 30 years prior, which suddenly experienced environmental conditions or abundance levels that triggered a population explosion.

QUESTIONS ASKED

While Norway contemplates the "invasion of giant king crab," Alaska is concerned about the inability of crashed stocks to recover and the impacts on healthy target fisheries, which may be part of areas closed to encourage rebuilding. "Why," I naively asked, "couldn't we get some of those live kings to jumpstart the crab that were beginning to ball up in bays around Kodiak Island? Are they genetically the same?" Thompson and McCarty took that question to key crab scientists, resulting in the creation of an ad hoc committee of scientists, agencies, industry and community representatives and the support of the governor, resulting in a two-day shellfish seminar in Anchorage in December of 2004. Also, the attention of the Alaska Sea Grant program culminated in an international meeting of crab scientists (Norway, Chile, Canada, Russia, Japan and other nations) in Kodiak in March of 2006. More importantly, it started to attract funding. The effort has already gone far beyond what was imagined.

BLUE KING/RED KING

From the beginning, the intent of the ad hoc committee was to focus on two primary areas and species: (1) blue king crab from the Pribilof Islands in the Bering Sea, and (2) red king crab from Kodiak Island. Dr. Brad Stevens (formerly of NOAA) had already done considerable work on both species at the NOAA lab on Kodiak.

Crab enhancement is not a new topic. Jeff Stephens (United Fishermen's Marketing Association) of Kodiak points out that UFMA has been investigating interest since 1982. In January of 1992, Kodiak College of the University of Alaska system hosted a small workshop titled, "International Crab Rehabilitation and Enhancement Symposium." The symposium was held in response to a proposal from ADF&G to cultivate larval king crab and release them into the ocean. At that time, the idea of enhancing crab stocks was unprecedented, and nobody in the United States had ever cultivated crab of any kind, especially king crab. Dr. Brad Stevens adds, "at the conclusion of the meeting most of the participants agreed that stock enhancement of king crab was not currently technically feasible."

HOPE AT LAST

Dr. Stevens is hopeful, however, that new interest, research and technology may now have a different result. " Research on king crab cultivation has been conducted at the Kodiak Fisheries Research Center since 2000, primarily as a tool for ecological research. In 2004, we concluded a highly successful project with blue king crab. Our efforts have been conducted on a small scale, raising a few thousand crabs for use in experimental research, as opposed to the millions that will be needed for enhancement. However, the same techniques we use in the laboratory are applicable to commercial stock enhancement, if scaled up to a larger level."

Dr. Doug DeMaster, research and science director for NOAA Fisheries in Alaska, agrees. "This will be the time to find out if we can affect population dynamics or not. This is a priority issue of AFSC, and one that is entirely consistent with our mission to protect, restore and maintain healthy stocks of living marine resources. We view the current pilot projects as positive cooperation between government, scientists, industry and communities."

ENHANCEMENT EFFORTS

While enhancement of wild stocks might be the most plausible and environmentally friendly way to increase recruitment, Dr. Stevens is careful to point out that "enhancement" is not "crab farming."

"Our goals are not to develop 'farms' for crab, but rather to explore the feasibility of enhancing natural populations of crabs in the ocean," he said. "There are numerous methods for achieving that result; Aquaculture is one method that involves cultivation and release of small crabs. However, the goal is to produce early life stages, not a marketable product. Other methods of enhancement could involve placing settlement collectors in areas where larvae are abundant but habitat is scarce, then moving them to places where the juvenile habitat exists. Another could be to enhance juvenile habitat. None of these methods have been critically evaluated, much less undergone intense scientific or public scrutiny."

CRABS FEND FOR THEMSELVES

Dr. Stevens makes further distinctions. "There is a major difference between "stock enhancement" as defined here, and "aquaculture." The goal of enhancement is to place juveniles into the ocean where they will grow and become adult crabs subject to recapture by commercial fishermen. Released crabs are not fed, and need to fend for themselves for the rest of their lives. For that reason, it is a supplement to the wild fishery. Furthermore, brood-stock are recaptured from the ocean each year, so the quality of "seedlings" produced is equivalent to those produced naturally. This differs completely from controlled aquaculture, in which animals (e.g., fish, crayfish, shrimp) are raised in a completely artificial environment (land-based tanks or ponds), or in net pens suspended in the ocean. In that type of aquaculture, the entire lifecycle of the animal is controlled from birth to capture, and they are fed artificially the entire time. That creates a new industry separate from, and competing with, the wild capture fishery. "Seedlings" are generally produced from captured stock, or fish that return to the hatchery, which results in inbreeding, loss of genetic variability, and decreased quality over time."

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