Monday, December 21, 2009
Is NMFS science cheating snow crabbers?
Some tension always exists between the fishing industry and government scientists over official estimates of just how much fish and shellfish is out there.
The scientists survey the population, then bring the results back to fishermen and processors. Generally, it seems to me the industry has a fairly high degree of trust in the work the scientists do in Alaska, unlike in other parts of the country.
But now comes an apparent admission from the National Marine Fisheries Service in Seattle that surveys for eastern Bering Sea (EBS) snow crab, a multimillion-dollar commercial stock, might be suspect.
The issue is just how good a job the government's survey trawl does in netting snow crab on the seafloor for purposes of estimating abundance. These estimates, of course, have a huge bearing on how many snow crabs the "Deadliest Catch" fleet can harvest.
This past July, according to this brief NMFS report, government scientists and industry players conducted a cooperative experiment on the snow crab grounds to test the standard NMFS survey trawl.
Part of the experiment involved towing two alternative nets, including a modified NMFS trawl and one from an industry organization, the Bering Sea Fisheries Research Foundation. The foundation's trawl is designed for the European Norway lobster fishery.
You can read the NMFS report for full details, but the bottom line is that the foundation's net is a much more effective crab catcher than the NMFS nets, including the one that was modified to improve its catch rate.
Here's the key paragraph from the NMFS write-up:
"Preliminary results show that more escapement of snow crab under the footrope of the EBS survey trawl occurs than previously estimated. Specifically, only 35% of the large males, 27% of the pre-recruit males, 13% of the small males, 25% of the large females, and just 3% of the small female snow crab in the path of the survey trawl are captured."
Deckboss put the following question to Steve Minor, a crab industry lobbyist and chairman of the Pacific Northwest Crab Industry Advisory Committee:
"Is the government short-changing the crab industry because of a flawed stock survey?"
Minor replied: "Let's just say that stock assessment science is evolving."