WEBB, J.B.*; ECKERT, G.L.; SHIRLEY, T.C.; TAMONE, S.L.; DUTTON, J.M.; Univ. of Alaska Fairbanks; Univ. of Alaska Fairbanks; Univ. of Alaska Fairbanks; Univ. of Alaska Fairbanks; Univ. of California, Santa Barbara: The consequences of incubation temperature for zoea of the snow crab, Chionoecetes opilio

Cold temperatures increase development time across many invertebrate taxa, however the consequences of increased development time are largely unknown. For the snow crab, Chionoecetes opilio, the duration of both larval and embryonic development is increased at lower temperatures. As a stenothermic inhabitant of continental shelf and slope environments in the northern Atlantic and Pacific oceans, snow crab are highly adapted to cold temperatures (-1 to 5� C). In this study ovigerous female snow crab were collected by trawl and pot from the eastern Bering Sea in the summers of 2001 and 2002 and were held at five temperature treatments (-1, 0, 1, 3, and 6� C) in the laboratory for the duration of the reproductive cycle. Embryonic development was tracked and zoeae were collected upon hatching to assess the effect of incubation temperature on larval morphology, energy content, and weight. The mean duration of incubation increased by approximately 30 days per degree drop in temperature. Incubation temperature did not affect zoeal weight or energy content. Zoeal morphology changed with incubation temperature. Rostro-dorsal, dorsal, and lateral spine lengths were smaller at the warmest and coldest temperatures than at intermediate temperatures. The lateral process of the third abdominal somite increased in length with increasing incubation temperature. Plasticity in spine length due to varying incubation temperature could have important implications for zoeal feeding, motility, and defense.