Meeting Abstract

P1.54  Sunday, Jan. 4  Ontogeny of morphology and feeding kinematics in Lingcod (Ophiodon elongatus) BEN-ADERET, N.J.*; DEAN, M.N.; Bar-Ilan University; University of California, Irvine nbenaderet@gmail.com

Habitat shifts often require alterations or flexibility in feeding behavior and/or morphology. These changes may be necessary to adjust to a different prey base and are particularly vital for habitat changes during early ontogeny, where the energy demands of rapid growth put a premium on capture performance exceeding the escape performance of prey. In this study, we used high-speed videography to examine ontogenetic changes in morphology and feeding kinematics across an age-series of lingcod (Ophiodon elongatus), a dominant, temperate Pacific predator that shifts from soft-bottom inshore to rocky-reef habitats during the 1st year of its life. As lingcod age, they feed on proportionately larger prey items; although we predicted older lingcod would exhibit morphological and behavioral shifts toward relatively larger feeding structures, maximum gape and hyoid depression scaled with strong isometry and cranial length decreased relative to body length with age. There was no clear ontogenetic pattern in the employed feeding mode, as quantified by the Ram-Suction index: at all sizes, lingcod exhibit both suction- (min. RSI = 0.05) and strongly ram-based (max. RSI = 0.693) feeding events. However, larger lingcod are proportionately faster in completing feeding movements and, when initial strike distance is scaled to predator body length, begin their strikes relatively closer to the prey item. These data provide a functional morphological context for a commercially important rocky reef predator and suggest that lingcod can remain successful predators across a habitat and prey shift through changes in behavior, not morphology or feeding mode.