Ecology of the Ras Muhammad Crack in Sinai

Abstract

CRACKS running through raised Pleistocenic coral reefs form a common environment around the tropical Indian and Pacific Oceans. The cracks can be reached only when they have an opening to the surface of the dry raised reef, and therefore the biota found in the open cracks is a mixture of light-avoiding subterranean species and of shadow-loving marine species. Near the southern tip of the Sinai Peninsula, Cape Ras Muhammad (Fig. 1), an open crack of about 40 m length and 0.20–1.5 m width and about 150 m inland, was discovered in October 1971 (Fig. 2). It is possible, with difficulty, to descend into the crack and dive to depths of over 14 m.