Environmental Conservation

Papers

Beach rock as a keystone habitat for amphibious sea snakes

XAVIER BONNETa1 c1, FRANÇOIS BRISCHOUXa1, DAVID PEARSONa2 and PHILIPPE RIVALANa1

a1 Centre d'Etudes Biologiques de Chizé, CEBC-CNRS UPR 1934, 79360 Villiers en Bois, France

a2 Department of Environment and Conservation, PO Box 51, Wanneroo, WA 6946, Australia

SUMMARY

The shorelines of coral islets are subject to strong anthropogenic pressure, being highly coveted for tourism. These landforms contain unique biotic assemblages but unfortunately are limited in size making them extremely vulnerable to perturbation. Robust information linking habitat structure and species requirements is urgently needed to promote and guide the conservation of these fragile areas. New Caledonia contains critical shore habitats for two species of amphibious sea snakes. One species (Laticauda laticaudata) shelters almost exclusively under mobile beach rocks, which are both easily accessible from the sea and regularly submerged at high tide. The scarcity of such specific and spatially limited habitat restricts the distribution of this species to highly localized areas. The other species (L. saintgironsi) uses a greater variety of terrestrial refuges, but has a preference for shores with abundant beach rocks. These findings offer a robust basis to promote the conservation of these crucial habitats and to justify their inclusion in marine protected areas (MPA), which in turn should benefit a wide array of other organisms also dependent on beach rocks.

(Received October 23 2008)

(Accepted February 11 2009)

(Online publication April 16 2009)

Correspondence

c1 Correspondence: Dr Xavier Bonnet e-mail: bonnet@cebc.cnrs.fr