Vacant Bivalve Boreholes Increase Invertebrate Species Richness in a Physically Harsh, Low Intertidal Platform

BAGUR, MARÍA; PALOMO, M.; GUTIÉRREZ, JORGE; ARRIBAS, LORENA

Diversity

MDPI

Lugar: Basel; Año: 2019 vol. 11 p. 39 - 51

1424-2818

Ecosystem engineers can modulate harsh abiotic conditions, thus creating habitat forspecies that cannot withstand the local environment. In this study, we investigated if vacantboreholes created by the rock-boring bivalve Petricola dactylus increase species richness in thelow intertidal zone of a Patagonian rocky shore characterized by intense hydrodynamic forcingand sediment scour. Invertebrate species richness was three times higher in engineered thanunengineered habitats (i.e., with and without Petricola boreholes, respectively) and the increasein species richness was area-independent. The most prevalent species in unengineered areasshowed strong adhesion mechanisms, whereas infaunal and vagile species were mostly restrictedto boreholes. The positive influence of engineered microhabitats on species richness can largelybe attributed to amelioration of physical conditions, particularly a reduction in hydrodynamicforces and sediment trapping/stabilization within boreholes. We conclude that vacant boreholes areessential microhabitats for the maintenance of biodiversity within the otherwise inhospitable lowintertidal zone.