Influence of biogenic habitat on the recruitment and distribution of a subtidal xanthid crab

Abstract

Biogenic habitat can structure marine communities by serving as both a complex substrate and food source for adult and recruiting organisms. We investigated the role played by biogenic habitats (Mytilus edulis and Crepidula spp. beds) in influencing the subtidal distribution (kilometers scale) of the mud crab Dyspanopeus sayi in Narragansett Bay, New England (USA). In field surveys, D. sayi were 1 to 2 orders of magnitude more abundant on M. edulis and Crepidula spp. beds than at sites lacking these habitats, and a laboratory experiment confirmed that D. sayi will consume both of these species. In a field-based, substrate-choice experiment, modules containing rocks had higher D. sayi recruit densities than those containing M. edulis or Crepidula spp. This indicates that structural complexity of those biogenic substrates, rather than their availability as prey, is the primary factor influencing patterns of D. sayi recruitment. Densities of recruit and adult D. sayi on recruitment modules were higher at bare sites than at sites with biogenic habitat, where modules represented islands of structure in otherwise simple habitat. This suggests small-scale habitat selection by D. sayi. Adult D. sayi occupied modules indiscriminately at bare sites, but exhibited a preference for modules containing mussels at sites with biogenic habitats. The importance of structure for adult and recruit D. sayi, reinforced by adults' response to prey presence, likely explains this organism's association with hard, biogenic habitats in the studied system.

Field Assessment of the Predation Risk - Food Availability Trade-Off in Crab Megalopae Settlement

“…In a similar study [33], it was shown that the geometric complexity of the habitat was ecologically more important than food availability for settling megalopae of Dyspanopues sayi .Similar results were found for Carcinus maenas and Paralithodes camtschaticus [28], [48]. This indicates that the findings in this study, independent of field conditions, confirm the great relevance of predation as an indirect control on the settlement process of decapod megalopae.…”

“…Although these factors have been recognized as key in the settlement process, there are few studies that assess a trade-off between them and their relative effect on settlement success in brachyurans [5], [33], [34].…”

First record of Say's mud crab Dyspanopeus sayi (Brachyura: Xanthoidea: Panopeidae) from the Black Sea

“…Other preferred habitats are oyster reefs, mussel beds, the bodies of red-beard sponge Clathria prolifera (Ellis & Solander, 1786), seagrass meadows, rocks and coarse gravel (McDermott & Flower, 1952;Strieb et al, 1995;Mizzan, 1999). Structural complexity is the primary factor influencing D. sayi preferential recruitment on biogenic habitats; later adults also respond positively to the prey value of the engineering species (Lindsey et al, 2006).…”

Inducible variation in hypoxia tolerance across the intertidal–subtidal distribution of the blue mussel Mytilus edulis

“…Increased ability for anaerobiosis induced by aerial exposure should lead to greater tolerance for submergence in hypoxic water as well. This study was conducted in Narragansett Bay, Rhode Island, USA, where mussels create essential habitat that structures the distribution of associated infauna (Lindsey et al 2006). Severe eutrophication in Narragansett Bay generates periods of water-column hypoxia which can lead to local extinction of the mussels and loss of their ecological functions .…”