The effects of an invasive habitat modifier on the biotic interactions between two native herbivorous species and benthic habitat in a subtidal rocky reef ecosystem
Elisabeth MA Strain, Craig R Johnson
BIOLOGICAL INVASIONS | SPRINGER | Published : 2013
Range expanding species can have major impacts on marine ecosystems but experimental field based studies are often lacking. The urchin Centrostephanus rodgersii has recently undergone a southerly range expansion to the east coast of Tasmania, Australia. We manipulated densities of C. rodgersii and algal regrowth in urchin barrens habitat to test effects of the urchin on biotic interactions between two native herbivores, black-lip abalone (Haliotis rubra) and another urchin (Heliocidaris erythrogramma), and their benthic habitat. After 13 months, removals of only C. rodgersii resulted in overgrowth of barrens habitat by algae and sessile invertebrates. Densities of abalone increased (+92 %) o..View full abstract
We thank those who assisted with fieldwork, particularly Ryan Downie, Richard Holmes and David Sinn. We thank Dr. Graham Edgar and Dr. Adriana Villamor for their useful comments on an earlier draft of the manuscript. This study was part of a Commonwealth Scientific and Industrial Research Organization Joint PhD Program in Quantitative Marine Science and supported by an Australian Postgraduate Award. The research was supported by Tasmanian Aquaculture and Fisheries Institute, and Tasmanian Abalone Council grants.