The marine turtles of the Arabian Gulf NCWCD studies 1991-1994

Mustafa Al-Merghani, Jeff D. Miller, Ahmad Al-Mansi, Omar Khushaim and Nicolas J. Pilcher

A b s t r a c t: The populations of green (Chelonia mydas) and hawks bill (Eretmochelys imbricata) turtles nesting on the offshore islands of Karan and Jana in the Arabian Gulf were monitored during the summer nesting seasons of 1991-1994 to collect information on nesting behaviour, morphometrics, and to estimate the number of hatchlings produced. The study found that the morphological data for adult female turtles were similar to that collected in previous years from the same locality. However, marine turtles of the Arabian Gulf are slightly smaller than those found elsewhere in the world (mean weights: green turtle 106.9 kg, hawksbill 39.1 kg). The nesting habits of the Saudi Arabian turtles were also similar to nesting behaviours reported elsewhere. The average number of eggs laid by green and hawks bill turtles is lower (green: 84.4, hawks bill: 83.8) than for these species nesting elsewhere but the hatching success is about the same (green: 80 %, hawksbill: 71 %). To conserve the marine turtle populations in the Arabian Gulf, the cooperation of all the regional states is needed. An outline for developing a regional management plan for the conservation of both species is presented.

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