Population study of foraging Green sea turtles (Chelonia mydas) in the Northern Persian Gulf and Oman Sea, Iran

Abstract

We conducted a study on foraging green sea turtles (Chelonia mydas) in the Northern Persian Gulf and Oman Sea to describe population structure, distribution, habitat preferences, and genetic structure. In total, 139 sea turtles from different size classes were examined from eight sites. Minimum and maximum curved carapace length and weight recorded were 26–96 cm and 2.3–97 kg, respectively.To assess the genetic structure we sequenced a total of 62 individuals for 750 bps of the mitochondrial DNA control region. Two main clades with 29 and 33 individuals were detected, sharing individuals from all sampling sites. A total of 9 haplotypes were recognized, with overall haplotype diversity (h) of 0.8054 and nucleotide diversity (π) of 0.01470.Of the nine haplotypes, only three haplotypes had already been reported (one from Australia, two from Saudi Arabia) three new haplotypes were detected and the remaining three were unpublished. According to the existence of regionally important nesting populations in the area, mixed stock analyses (MSA) was used to estimate the contribution of each rookery in the foraging populations in the Northern Persian Gulf and Oman Sea. Excluding the found orphan haplotype, which indicated that there are still under-sampled or unsampled rookeries in the region, MSA indicates that 94% of the remaining turtles originated from Oman. Considering the formation of isolated population, new genetic structure, and threatening factors in the region, the green sea turtle populations are in need of conservation measures.