Discovery of the first Mascarene giant tortoise nesting site on Rodrigues Island, Indian Ocean (Testudinidae: Cylindraspis )

Five species of giant tortoise (genus Cylindraspis) once occurred in huge abundance on the Mascarene Islands of Mauritius, Reunion, and Rodrigues. They disappeared after colonisation of the island by humans in the 17th and 18th centuries, primarily due to over-hunting and predation of eggs and young by introduced pigs and cats. So rapid was their extinction that virtually nothing is known about their life history, especially nesting and egg-laying behaviour. Here we report the discovery on Rodrigues of the first Mascarene tortoise-nesting site, which contained intact nesting chambers, complete egg clutches and fossil remains of a known native predator of tortoise eggs. We further compare the nesting behaviour with the giant tortoises of Aldabra Atoll in the Seychelles and the Galapagos Archipelago in Ecuador and provide details of the decline and extinction of Mascarene tortoises, most notably those of Rodrigues, for which good historical records exist.