Manmade Rocky Shore Habitats Create Stress on Existing Biota.

Abstract

The present study investigated the effects of artificial rocky shore habitats on the wellbeing of intertidal macro-benthic communities. Manmade rocky shore which is constructed for preventing coastal erosion and natural rocky shore were selected as study sites from the Rumassala Marine Sanctuary, Galle, Sri Lanka. Stratified sampling method was applied to quantify the sampling biota from three zones along the tidal gradients at two study sites. Species richness index, species diversity and community evenness were calculated using PRIMER software. Index of disturbance, as a measure of stress was quantified for two communities. A total of 28 species were recorded from natural rocky shore environment compared to 13 species in the manmade rocky shore. Of the two communities studied, total number of individuals, species richness and Shannon Weiner diversity index was comparatively higher in natural rocky shore habitats. Index of disturbances were higher in natural rocky shore community, showing less stress to existing biota over the community existing in artificial rocky shore habitats. Present study indicates that man made habitat appears to be unable to support or attract the diversity and abundance of species found in natural rocky shore communities, and existing biota are in stressed condition..