Meeting Abstract

105.2  Saturday, Jan. 7  Impacts of elevated seawater temperature on Antarctic amphipod feeding choices for chemically-deterrent macroalgae SCHRAM, J.B.*; MCCLINTOCK, J.B.; AMSLER, C.D.; BAKER, B.J.; Univ. of Alabama at Birmingham; Univ. of Alabama at Birmingham; Univ. of Alabama at Birmingham; Univ. of South Florida jbschram@uab.edu

As global temperatures continue to increase as part of the phenomenon referred to as climate change, the Western Antarctic Peninsula (WAP) is predicted to continue to be among the geographical regions with the highest rates of seawater warming. The sensitivity of marine invertebrates to changes in temperature varies widely geographically and by species. Temperature impacts on Antarctic marine invertebrates, a group known to be highly stenothermal, can be dramatic and small changes in temperature can have large effects on aspects of their physiology, growth, and species distribution. We examined the effects of end-of-century predicted seawater temperature (3.5 C) on the feeding choices of the ecologically dominant omnivorous amphipod Gondogeneiea antarctica. Amphipods were given a choice between artificial food prepared with and without macroalgal chemical extracts with known, moderately deterrent properties. Identical feeding trials were conducted simultaneously at an ambient seawater temperature of 1.5 C. We observed temperature-induced alterations in amphipod feeding preferences to food pellets containing lipophilic or hydrophilic extracts of the seven macroalgal species examined. Our results suggest that rapidly rising seawater temperature could impact trophic interactions in the macroalgal communities of the WAP.