Meeting Abstract

55.4  Tuesday, Jan. 6  Sublethal predation in an ecosystem engineering polychaete BERKE, Sarah K*; CRUZ, Veronica; Smithsonian Environmental Research Center; Florida State University skberke@gmail.com

Sublethal predation, in which a prey organism is partially eaten but not killed, is an important process in terrestrial and marine ecosystems. When sublethal predation involves ecosystem engineers, it may potentially influence spatial and temporal variation in bioengineered habitat. We examined sublethal predation in a marine ecosystem engineer, the tube-building polychaete Diopatra cuprea. D. cuprea tubes form dense assemblages that facilitate infaunal and macroalgal communities, enhancing local diversity and productivity. D. cuprea commonly loses its antennae and portions of its anterior to predator attacks; lost body portions are subsequently regenerated. We asked (i) whether the intensity of sublethal predation differs for D. cuprea populations in Virginia versus Florida, (ii) whether sublethal predation varies seasonally in each region, (iii) whether sublethal predation influences activity and tube-building rates, and (iv) how sublethal predation contributes to secondary productivity. Within Florida, we also drew comparisons between D. cuprea and the closely related onuphid Americonuphis magna. Surprisingly, we found that that sublethal predation is more intense in Virginia compared to Florida, likely constituting an important link in regional food webs. Within Florida, sublethal predation was more intense in late summer than in early summer. Both antennae loss and anterior loss affected D. cuprea activity rates. Anterior loss dramatically reduced tube-construction rates for many days post-injury. Although D. cuprea and A. magna have similar ecologies and life-histories, A. magna is incapable of anterior segment regeneration, raising interesting questions about the evolution of anterior regeneration within the Onuphidae.