Baseline monitoring gastropods in the intertidal zone of Qatar - target species and bioindicators for hyper-thermic and hyper-saline Conditions

Abstract

The Arabian Gulf is subjected to some of the most intense sea water temperatures and salinity levels in the world. In an attempt to understand the distribution and species composition of gastropod assemblages which live in these hyper-thermic and hyper-saline conditions a rapid assessment survey was undertaken along the intertidal zone of Qatar. The research revealed an obvious geographical temperature/salinity gradient between sites on the southeast and southwest coastlines. Water temperatures of 34°C and salinities ranging from 39.9 to 56.8ppt were recorded in-situ. There was detectable change in gastropod assemblage composition in accordance with this gradient. The abundance and diversity of live species decreased as temperature and salinity rose while high densities of dead species were recorded at sites where extremes of temperatures and salinities were documented. Ceritidiopsila conica was the dominant species at sites which experienced the most extreme conditions and has value as a recognized bio-indicator of high temperature/salinity environments within the region.