MEPS 456:43-51 (2012)  -  DOI: https://doi.org/10.3354/meps09647

ABSTRACT: Epibiotic assemblages provide an important source of primary and secondary production in seagrass habitats. Surrogates for biodiversity, such as broad-scale habitat types, have been used in selecting marine park boundaries and zones. As a preliminary test of one assumption of surrogacy that in effect treats all seagrass species as equal, the epibiotic assemblages of pairs of seagrass species, including the regionally rare Posidonia coriacea, were sampled between homogeneous or heterospecific patches at 3 separate locations in South Australia. Three seagrass species, each with distinct morphology, had distinguishable epifaunal assemblages. Free-living epifauna showed clear selection between seagrass species with movement likely over small scales within heterospecific patches, but no such distinction was shown when the same seagrass species pair was separated rather than intermingled. Epiphytic sessile species showed less well-defined specificity among seagrass species, but there were still significant differences in epiphytic species richness. The results of this preliminary study suggest that marine conservation planning needs to consider seagrass habitat on a species-by-species basis, including how they are arranged within localised patches.

KEY WORDS: Amphibolis antarctica ^. Epifauna ^. Epiphyte ^. Field surveys ^. Marine conservation planning ^. Posidonia coriacea ^. P. sinuosa ^. South Australia