Amanda Colton
Univ. of New England
Studied larval Pacific cod.

Working with scientists from the Fisheries Behaviorial Ecology Program in Newport OR, I studied the role that visual and olfactory cues play in aiding larval Pacific cod and walleye pollock locate and remain within patches of high prey concentration.

Behavioral responses of larvae were examined in two types of experiments. "Gradient Trials" evaluated the behavioral responses of fish to uneven distributions of light, prey scent, and live prey. In "Patch Trials", I determined if larvae alter their swimming behaviors when in a feeding patch.

Overall, I found that the two species have very similar foraging mechanisms, which include an ontogenetic reversal in the behavioral response to light gradients and a strengthening responsiveness to prey. Larvae of neither species exhibited a behavioral response to prey scent, suggesting that olfaction in prey detection may be restricted to later life stages in these species.