Scientia Marina, Vol 72, No 3 (2008)

Mitochondrial DNA reveals regional and interregional importance of the central Mediterranean African shelf for loggerhead sea turtles (Caretta caretta)

Paolo Casale
Department of Animal and Human Biology, University of Rome 1 ‘La Sapienza’, Italy

Daniela Freggi
Sea Turtle Rescue Centre WWF Italy, Italy

Paolo Gratton
Department of Biology, University of Rome 2 ‘Tor Vergata’, Italy

Roberto Argano
Department of Animal and Human Biology, University of Rome 1 ‘La Sapienza’, Italy

Marco Oliverio
Department of Animal and Human Biology, University of Rome 1 ‘La Sapienza’, Italy


The wide north African continental shelf in the central Mediterranean is known to be one of the few important areas in the basin for loggerhead turtles in the neritic stage. In order to assess the origin of these turtles, sequences of the mtDNA control region were obtained from 70 turtles caught by bottom trawlers in the area, and compared with known sequences from turtles from Mediterranean and Atlantic nesting sites. Five haplotypes were identified (Haplotype diversity = 0.262; nucleotide diversity = 5.4×10-3). Specific haplotypes indicate contributions from distant rookeries such as Turkey and the Atlantic, which shows that Atlantic turtles entering the Mediterranean while in the oceanic phase use at least one Mediterranean continental shelf as a neritic foraging ground. A new haplotype and another one previously found only in foraging areas, highlight the genetic information gaps for nesting sites, which undermine powerful mixed stock analyses. Despite these limitations, the results reveal the regional importance of the study area as a neritic foraging ground for turtles that are probably from most of the Mediterranean nesting aggregates. Therefore, reducing turtle mortality resulting from the high fishing effort in the area should be regarded as key for Mediterranean turtle conservation and is also possibly important for Atlantic populations.


Caretta caretta; mtDNA; Mixed Stock Analysis; conservation; Mediterranean

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