These studies further emphasized that early developmental stages of corals are particularly vulnerable. For example, Rinkevich and Loya (1977) recorded decreased viability and reduced settlement rates of S. pistillata planulae exposed to increasing WSFs of oil. Loya and Rinkevich (1979) further demonstrated the abortion of immature planula larvae by gravid colonies in response to low WSFs exposure. Using this scientific background, the purpose of the present study was to test possible acute effects of chemically dispersed Egyptian crude oil (the major oil type imported to Israel through Eilat) by ®ve approved-to-use dispersants, on planula larvae of S. pistillata and H. fuscescense. Shortterm assays (up to 96 h) monitored planulae survivorship, settlement rates, morphological and behavioural abnormalities in order to rank the dispersants in accordance to their relative negative impacts on the coral larvae.