Bivalves as ecosystem engineers in Patagonian rocky shores

BAGUR M.; PALOMO M.G.; ARRIBAS L.P.; GUTIERREZ J.L.

Monterey

Congreso; 100th Anniversary Western Society of Naturalists; 2016

Western Society of Naturalists

Structural modification of the environment by physical ecosystem engineers often allow for the occurrence of species that are not able to establish in unengineered habitats, thus leading to increased species richness at the landscape-level. This study investigates the contribution of mussels (Perumytilus purpuratus) and perforating bivalves (Lithophaga patagonica and Petricola dactylus) to rocky intertidal species richness in Patagonia, Argentina. Our results show that bivalves-engineered patches harbor a substantial number of invertebrate species in addition to those occurring in the unenegineered rock substrate. Furthermore, when co-ocurring in the same site, different bivalves? species can complementary contribute to overall species richness, since the distinctive habitat patches created by each engineer add exclusive subsets of species to the study area. We found that complementary engineering effects on landscape-level species richness occurs when the engineered patches structurally differ from each other and vary in their relative ability to modulate two or more abiotic conditions and/or resources that prevent species establishment in the unengineered state. This study highlights the importance of ecosystem engineers in harsh environments