Woods Hole Oceanographic Institution

»Publication 0
»Mar Ecol 2000
»Appl Env Microb 2000
»FEMS Microb Ecol 2001
»Appl Env Microb 2005
»Deep-Sea Res 2006
»Env Micro 2006
»Aquat Microb Ecol 2006, 1
»Aquat Microb Ecol 2006, 2
»GCA 2009
»FEMS Microb Ecol 2009
»Aquat Microb Ecol 2010
»GCA 2010
»Org Geochem 2010
»Env Micro 2010
»L & O 2011
»ES&T 2011
»GCA 2011
»Env Res Letters 2011
»Org Geochem 2012
»Geomicro accepted

Van Winkle, D.H., K. Longnecker and N.W. Blackstone, The effects of hermit crabs on hydractiniid hydroids, Marine Ecology, 2000, 21(1):55-67

Hermit crab shells are often encrusted with diverse communities of epibionts. To explore the effects of hermit crabs on the interactions of these encrusting species, two species of hydractiniid hydroids, Hydractinia symbiolongicarpus and Podocoryna carnea, were examined in the presence and absence of Pagurus longicarpus hermit crabs. Colonies growing on Littorina littorea snail shells with hermit crab hosts were compared to those growing on shells without crabs. These experiments suggest that hermit crabs variably affect colony polyp number, colony morphology and the outcome of interspecific competition, according to the size and number of crabs; other factors include water temperature, food availability and hydroid clonal genotype. In order to allow image analysis of perturbations of colony morphology, hydroids were grown on glass surfaces both exposed and unexposed to hermit crabs. Relative to colonies growing on unexposed surfaces, colonies growing on exposed surfaces exhibited larger within-colony patches, thus decreasing the total encrusted surface area and polyp number of colonies. Further, on glass surfaces, hermit crabs accelerated the time to the resolution of interspecific competition (i.e., the overgrowth of one colony by the other). While a number of factors may contribute to the relative abundance of these encrusting species, under most circumstances P. longicarpus have large effects on hydractiniid hydroids. Mechanisms underlying these effects likely include hydrodynamics and mechanical disturbance.

© Woods Hole Oceanographic Institution
All rights reserved