Intertidal mussels as ecosystem engineers: their associated invertebrate biodiversity under contrasting wave exposures

Abstract

Mussels often act as ecosystem engineers in rocky intertidal habitats, favoring the occurrence of many small invertebrates by increasing habitat complexity and improving local environmental conditions. This study tests the hypothesis that invertebrate assemblages from intertidal mussel beds differ between wave-sheltered and wave-exposed habitats. To this aim, we surveyed exposed and sheltered sites spanning 350 km of coastline in Nova Scotia, Canada. We identified all invertebrates and measured their abundance in replicate quadrats that were fully covered by mussels. In total, we found 50 invertebrate taxa living in these mussel beds. Multivariate analyses revealed that the composition of invertebrate assemblages differed significantly between both habitat types. Exposed habitats supported a greater species richness, and the species that mainly explained the compositional difference between both environments were more abundant in exposed ones. Assemblages were taxonomically dominated by arthropods, annelids, and molluscs and numerically dominated by tubificid oligochaetes regardless of exposure. Our results suggest that exposed habitats may favor the occurrence of filterfeeders, such as barnacles, and sheltered habitats the occurrence of predators, such as small crabs and sea stars, in intertidal mussel beds from the NW Atlantic coast.

Interactive effects of ocean acidification and warming on subtidal mussels and sea stars from Atlantic Canada

“…On the one hand, predation pressure on M. edulis could decrease, allowing mussels to dominate the available substrate, decreasing the diversity of primary-space holders (Lubchenco & Menge 1978). On the other hand, the increase in microhabitat complexity caused by mussel beds could increase the Acidification and warming effects on mussels and sea stars 345 diversity of small invertebrates, which normally thrive among the mussels (Arribas et al 2014). Additionally, a higher growth rate of mussels under future conditions could lead to greater predation escape through faster attainment of a size refuge (Sommer et al 1999).…”

“…Asterias rubens preys heavily on M. edulis (Lubchenco & Menge 1978;Gaymer et al 2001), thus influencing intertidal and subtidal community structure by opening the substrate for less-competitive species. Also, as mussels are ecosystem engineers, providing habitat for many small secondary species, biodiversity is altered with changes in mussel abundance (Arribas et al 2014). Changes in growth rates of these species, or in the consumption of mussels by sea stars, could therefore alter benthic community structure and diversity.…”

Spatiotemporal variation in the sign and magnitude of ecosystem engineer effects on lake ecosystem production

“…Midges (Diptera: Chironomidae) are widespread in lakes worldwide and exemplify other benthic invertebrates (e.g., annelids and mollusks) in their roles as ecosystem engineers (Armitage et al 1995, Guti errez et al 2003, Norkko et al 2006, Arribas et al 2014, H€ olker et al 2015. Midges (Diptera: Chironomidae) are widespread in lakes worldwide and exemplify other benthic invertebrates (e.g., annelids and mollusks) in their roles as ecosystem engineers (Armitage et al 1995, Guti errez et al 2003, Norkko et al 2006, Arribas et al 2014, H€ olker et al 2015.…”

Creating a window of opportunity for establishing ecosystem engineers by adding substratum: a case study on mussels

“…Mussels are reef‐forming ecosystem engineers that generate environmental heterogeneity, which increases habitat diversity in coastal ecosystems (Arribas et al. ). Through their gregarious behavior, mussels self‐organize in beds that form stable structures under a broad range of environmental conditions (Commito and Rusignuolo , Hunt and Scheibling , Van de Koppel et al.…”