Abstract:
The urgent need to conserve aquatic biodiversity and the lack of spatial data on biodiversity has motivated conservation planners and researchers to search for more readily obtainable information that could be used as proxies or surrogates. The surrogate taxon approach shows promise in some aquatic environments (e.g. intertidal) but not others (e.g. coral reefs, temperate rocky reefs). Estuaries are transitional environments at the land¿sea junction with a unique biodiversity, but are the most threatened of aquatic environments because of high levels of human use. The comparatively small numbers of conservation reserves means that estuarine biodiversity is poorly protected. Selecting additional conservation reserves within estuaries would be facilitated by the identification of a suitable surrogate that could be used in conservation planning. In one estuary in Southeast Australia, we evaluated separately the effectiveness of annelids, arthropods, and molluscs as surrogates for predicting the species richness, abundance, assemblage variation, and summed irreplaceability of other species and for coincidentally representing other species in networks of conservation reserves selected for each surrogate. Spatial patterns in the species richness and assemblage variation (but not summed irreplaceability) of each surrogate were significantly correlated with the spatial patterns of other species.
