World Status, Exploitation and Trade - WIDECAST

TheOMANPOPULATION:Chelonia mydasNesting sites A large population nests at Ras al Hadd, the eastern-mostpoint of Oman's coast, while minor nesting beaches exist near Salalah (nearthe border with PDR Yemen), at Ras Madraka, on Masirah and the nearbymainland, at Ras Jilcsh, at Al Ashkara (Ross and Barwani, 1982), also in theDamaniyat Islands at Bandar Jissah, around Ras al Khayran, Khaysat ashSheikh, Sitat ash Shaikh, As Sifah and Ras Abu Daud, all in the Capital Areaof Oman (lUCN, 1986b). The species appears to nest on most beaches in theDhofar area, with the partial exception of Salalah Bay where humaninterference means that nesting is minimal. However, nesting habitat is notcontinuous: in the west of Dhofar limestone cliffs drop straight to the sea,and in the east there is much rock on the beach, and nesting females maymake many trial nest excavations (L. Barratt pers . comm. , March 1986;unpublished observations).Nesting numbers Ross and Barwani (1982) reported that a minimum of 6000females nested annually on the 11 km of beach at Ras al Hadd, while up to afew hundred might nest at each of the eight minor nest sites named above.Data presented by Ross (1987) indicate that from 1983 to 1987 between 40 000and 150 000 nests of C. mydas were laid at Ras al Hadd each year. However,Ross ( in litt . 27 July 1988) cautioned that these estimates were based oncounts of tracks from only one night per week and that no allowance was madefor false crawls. He therefore considered that they were excessive andchose to stand by his earlier estimate of 6000 females per year. Ross(1985) estimated the Masirah nesting population at 200 annually. There arearound 1000 nests made in the Capital Area, approximately 80% of these inthe Daymaniyat Islands, representing perhaps 300 females annually. Up to 30females of C. mydas and C. caretta combined may nest nightly on certainbeaches in Dhofar, but the proportion of C. mydas is unknown, and nesting isscattered, beaches adjacent to those with much nesting perhaps havingvirtually no nesting (L. Barratt, pers. comm. . March 1986; unpublishedobservations ) .Trends in nesting numbers There is no evidence that numbers were greaterin past times although the Ras al Hadd population seems now to be subject tosome disturbance arising from development and recreational use of the beach.Nesting season Although nesting takes place throughout the year at Rasal Hadd, this is at a low level from January through to July; most nestingoccurs between August and December, with about half of the annual total inAugust-September. The peak is about a month later on Masirah, with overhalf the annual total occurring in September-October, and the seasonextending into January (there is no recorded nesting in February-May) (Rossand Barwani, 1982). Green Turtles in the Greater Capital Area nest duringthe summer month, with a peak between July and October (lUCN, 1986b).Foraging sites Known feeding grounds are located to the west of Salalah,in Sawqira Bay, the Gulf of Masirah and along the Batinah coast (Ross andBarwani, 1982). Although the feeding area is extensive, stretching fromaround 800 km, quality and productivity are low. The predominant seagrassesare species of Halophila and Holodula which, according to Ross and Barwani,are hardy pioneer forms present in low biomass. Ross (1985) estimated, onthe basis of aerial surveys and mark recapture study, that 1000-3000 turtlesoccur on feeding grounds in the Masirah Channel, more than 99% of themC. mydas. nesting area of these turtles is unknown. Dense foragingpopulations occur off the Dhofar coast, often around 40 turtles being seenin one view (L. Barratt pers. comm., March 1986; unpublished observations);39A