Townsend's Shearwater Puffinus auricularis is a Critically Endangered seabird endemic to the Revillagigedo Archipelago of Mexico. The shearwater now breeds on only one island, Socorro, in the group, where it is at risk from predation by introduced feral cats Felis catus and habitat destruction by introduced domestic sheep Ovis aries.
The species formerly bred on Islas San Benedicto and Clarión in the Revillagigedos which still support ACAP-listed Laysan Albatrosses Phoebastria immutabilis (46 pairs in 2002/03 on the latter island; click here).
As well as from the cats and sheep, a recent publication by Jenny Carlson (Department of Biology, San Francisco State University, USA) and colleagues warns that the shearwater, and the other birds of Socorro, may now be now at risk from Plasmodium parasite-infected mosquitoes.
The island group has been listed on Mexico's World Heritage Tentative List from 2008 (click here for an earlier news item). The group has had an international status as a Ramsar Wetland of International Importance since 2004 (Site No. 1357). A management plan has been produced for the Revillagigedos, which are a Mexican Biosphere Reserve.
Carlson, J.S., Martínez-Gómez, J.E., Cornel, A., Loiseau, C. & Sehgal, R.N.M. 2011. Implications of Plasmodium parasite infected mosquitoes on an insular avifauna: the case of Socorro Island, México. Journal of Vector Ecology 36: 213-220.
Comisión Nacional de Áreas Naturales Protegidas 2004. Programa de Conservación y Manejo Reserva de La Biosfera Archipiélago de Revillagigedo. Tlalpan: Comisión Nacional de Áreas Naturales Protegidas. 220 pp.
Walter, H.S. & Levin, G.A. 2007. Feral sheep on Socorro Island: facilitators of alien plant colonization and ecosystem decay. Diversity and Distributions 14: 422-431.
Wanless, R.M., Aguirre-Muñoz, A., Angel, A., Jacobsen, J.K., Kent, B.S. & McCann, J. 2009. Birds of Clarion Island, Revillagigedo Archipelago, Mexico. The Wilson Journal of Ornithology 121: 722-729.
John Cooper, ACAP Information Officer, 19 July 2011