Ration and Temperature Effects on the Condition of Male Adolescent Molter and Skip Molter Snow Crab

Abstract

ABSTRACT This study examined the effects of ration and temperature on the molt of male adolescent snow crab Chionoecetes opilio (O. Fabricius, 1788). In one experiment, crabs were exposed to 1 of 4 treatments, 2 levels of ration and 2 levels of temperature. In a second experiment, all crabs were fed and a 4-level factor was addressed in which temperature was held constant as in experiment 1 (2 levels) or switched from one level to the other. Food consumption declined significantly and at a similar rate over time at both temperatures, several weeks before molt took place. Larger crabs molted to morphometric maturity in a greater proportion with no influence of ration or temperature. Smaller crabs also molted earlier than larger crabs. Temperature had a marked effect on the timing of molt, with crabs kept at a higher temperature molting 1 mo earlier and crabs exposed to shifted temperatures, molting midway between the two other groups. Body density decreased markedly at ecdysis, but was also influenced by r...