Growth per Molt of Snow Crab in the Eastern Bering Sea

Abstract

The growth per molt of snow crab Chionoecetes opilio in the eastern Bering Sea is poorly known, primarily because snow crabs are difficult to sample during their spring molting period due to the presence of sea ice. To provide better estimates of growth per molt for the stock assessment model used to manage the snow crab fishery, a study was conducted to collect juvenile crabs with a bottom trawler and return them to holding facilities at Dutch Harbor and Kodiak, Alaska. Since relatively few of these crabs subsequently molted, these data were augmented with molting data collected by two previous, unpublished studies. Based on a total of 35 observations, snow crabs grew according to the following premolt (PRM_W ) and postmolt (POM_W ) carapace width relationships: POM_W = −4.00 + 1.46(PRM_W ), where PRM_W < 36.1 mm, and POM_W = 48.83 + 1.17(PRM_W − 36.1), where PRM_W ≥ 36.1 mm.

Received July 23, 2012; accepted September 13, 2012

ACKNOWLEDGMENTS

We thank the staff of the Dutch Harbor office of the Alaska Department of Fish and Game (Heather Fitch, Rachel Alinsunurin, Britta Baechler, Ian Fo, Loren St Amand, and Trent Hartill) for help with the snow crab holding study, the staff of Unisea Inc. (Todd Shoup, Don Graves, and Guy Collins) for providing the dock and live tank facilities in Dutch Harbor, and the captain and crew of the F/V Half Moon Bay for their support through the rigors of snow crab sampling. This study was partially funded by the North Pacific Fisheries Research Foundation.