Abundance of old shell snow crab leads to quota cut
Crabbers took to the Bering Sea Oct. 15 for the opening of Bristol Bay red king crab season with a harvest quota equal to last year, but when boats hit the water in January to take snow crab they will have a catch of some 22 million pounds less than 2012.
At 2012 dockside prices of about $1.89 per pound, the 22-million pound cut for opilio, or snow crab, in 2013 is worth more than $40 million to harvesters and roughly twice that in first wholesale value for processors.
Overall, though, the net value of Bering Sea crab fisheries should be similar to last season, according to Alaska Being Sea Crabbers President Jim Stone.
Stone said he expects the decrease in quota to increase the price. He said a 25 percent increase in prices wouldn’t be surprising.
Wholesale prices are already rising, he said, an early indicator of that change. And Canada is also looking at a decreased harvest, Stone said, which helps the value of Bering Sea snow crab.
Although the snow crab fishery technically opens Oct. 15, harvesters don’t fish the stock until January. The 2013 total allowable catch, or TAC, for Bering Sea snow crab was set at 66.35 million pounds, a 25 percent cut compared to nearly 89 million pounds in 2012.
The snow crab harvest cut comes from a decrease in the mature male biomass (females may not be retained), and a change in the stock’s age composition. The crab is much older than in the past — about 60 percent of the mature male biomass is old shell crab — compared to about 37 percent last year.
The State of Alaska sets the TAC after the federal Crab Plan Team determines the over fishing limit, or OFL, and the acceptable biological catch, or ABC. The state, which sets the harvest strategy, may not set a quota that is larger than the ABC.
Federal managers cut the snow crab OFL for 2012-13, but only by about 10 percent. The rest of the harvest cut comes from the state harvest strategy.
When the proportion of old crab is higher, the state harvest strategy calls for a smaller harvest because those old shell crabs are less likely to be targeted or retained, said Fishery Biologist Doug Pengilly, from the Alaska Department of Fish and Game in Kodiak.
The industry prefers to catch and process young crab, Pengilly said. Young crab typically has a cleaner shell, without barnacles or other impurities just a year or two out from molt, Pengilly said. If boats are pulling up older crab, they can move fishing locations to avoid catching too much of it, he said.
According to a report from National Marine Fisheries Service, or NMFS, the amount of new shell crab in the catch was between 85 percent and 95 percent in the 2005-06 and 2007-08 fisheries.
The state harvest strategy accounts for this by assuming that a smaller proportion of the old shell crab will be caught. But when old shell crab is the majority of the stock, as it is now, that leaves less crab available for the quota.
Pengilly said it’s hard to say what the current age dynamics mean for the future of the stock. The changed proportion results from less recruitment — juvenile males reaching legal size — into the stock.
“There’s good years and bad years,” he said.
In a 2010 review of the crab rationalization program, federal scientists noted that large, clean crab are the most successful at mating. That same report — in the context of a section on “high-grading,” or discarding of old shell crab — cited 40 percent old shell crab for Bristol Bay red king crab in the 2005 survey as a larger proportion than in the past.
Pengilly said that how the stock fares in the future will depend on recruitment in coming years. If a lot of crab the forage size or larger enter the stock during the spring 2013 molt, then the age proportion might return to more typical level. Pengilly said.
On the other hand, if that doesn’t happen, the proportion of old shell crab could go up even more due to harvest of the preferred-age crabs and natural mortality.
Pengilly said the variation in recruitment is normal for snow crab.
“You don’t see just constant recruitment coming through from year to year,” he said.
Trends in recruitment observed in 2010 and 2011 were not seen in the 2012 survey, according to the Stock Assessment and Fishery Evaluation, or SAFE, prepared annually by NMFS, ADFG scientists and others
The SAFE document notes both that prosecution of young shell crab often takes them out of the fishery before they have a chance to reproduce, and that also that the older shell crab play less of a role in reproduction for the fishery.
Also at play in the snow crab fishery is the possibility of localized depletion, according to the SAFE.
That report noted that the exploitation rates for males in the southern part of the fishery near the Pribilof Islands may exceed the target harvest rate, although it also notes that there is some migratory movement in crab. That is listed as a possible conservation concern in the report.
Pengilly said it was hard to say whether or not localized depletion at play. The areas where 4-inch crab come out of the fishery are just a slice of the crab’s summer distribution. Last year, he said, ice coverage also limited fishing, which could be showing up.
Both Pengilly and the report noted that no tagging studies have been done to determine the exact patterns of crab movement. The snow crab fishery is closed in certain areas to protect Pribilof blue king crab stock, which has been closed to fishing for all but three of the last 20 years.
Bristol Bay king crab steady
Bristol Bay red king crab is the most valuable Bering Sea crab fishery. The 2012 TAC for that fishery is nearly identical to 2011 at 7.85 million pounds, despite some indications that the fishery may be on the decline.
Stone said that while king crab prices, particularly for the smaller specimens, have been decreasing, Bristol Bay red king crab prices will likely hold steady around $10 dollar per pound at the docks in Dutch Harbor.
In 2011, the fishery had an ex-vessel value of about $70 million with an average price of $9 per pound. According to the SAFE, recruitment has been low over the past few years, and is expected to remain that way in the near term, meaning that mature and legal crabs will continue to decline. Stock biomass has also declined since 2009.
Stone said an early boatload or two of Bristol Bay red king crab was delivered to the docks Oct. 15 for the ADFG observer cost recovery program.
“The scuttlebutt I’m hearing is that the crab is very nice,” Stone said.
St. Matthew’s blue king crab has a TAC of 2.03 million pounds, down slightly from 2.36 million pounds in 2011-12. Last year, only 80 percent of the St. Matthew’s blue king crab quota was actually harvested.
The Bering Sea tanner crab fishery will again be closed because the estimate of mature female tanner crab biomass is below the state’s harvest strategy threshold. It’s the third straight year the tanner crab fishery has been closed.
Federal scientists qualified the fishery as rebuilt when they released the 2012-13 stock assessments, but the state opted not to open it.
Molly Dischner can be reached at firstname.lastname@example.org.