The objective of this study was to relate environmental variables (prey concentration, temperature, wind speed, and water column stratification) to the condition of larval walleye pollock (Gadus chalcogrammus) in the southeastern Bering Sea to better understand how environmental variability influences larval condition. Condition of larvae was assessed (classified as good or poor) by using a flow-cytometry cell-cycle assay and a discriminant analysis model. A binomial generalized additive model then was used to relate larval condition to physical and biological oceanographic variables and to larval size. Water temperature and standard length (SL) of larvae were significantly related to the condition of larvae. Temperatures warmer than 3°C favored larvae of walleye pollock that were considered in good condition. Increasing larval size had a positive effect on condition, as larvae larger than or equal to 7 mm SL were more likely to be in good condition than smaller larvae. The condition of larvae smaller than 7 mm SL may be more sensitive to variability in prey abundance than larger larvae and, therefore, more vulnerable to a mismatch with prey.
Steven M. Porter (Wed,) studied this question.