Context-dependent success of restoration of a key species, biodiversity and community composition

Abstract

Increasingly, restoration is seen as a management and conservation tool, with aims of restoring not just a single species but a natural functioning community. In marine soft sediment systems, biodiversity and communities are often strongly related to the presence of key species, suggesting that restoration of a single species could result in restoration of communities/biodiversity. The success of such a restoration is likely to be context-dependent, driven by hydrodynamics, local diversity and ambient communities. A transplant experiment with adult Austrovenus stutchburyi was conducted in 2 different hydrodynamic compartments of a large New Zealand harbour. After 1 yr, densities of transplant sized individuals and smaller adults were enhanced at both sites, although enhancement of juveniles only occurred at 1 site. Measures of diversity did not increase in the experimental plots; however, at 1 site the benthic macrofaunal community had changed. Probable reasons for the location-dependent results are differences in hydrodynamic connectivity and ambient communities, although density-dependent effects driven by small differences in the success of adult enhancement may also have been important. © Inter-Research 2013.