The site boundary is based upon a seaward extension of 200 km around Clipperton to encompass the foraging range of IBA threshold numbers of Masked Booby based upon a 2003 population estimate of 112,000 individuals and Brown Booby based upon a 2003 population estimate of 25,000 individuals from Pitman, R., Balance, L. and Bost, C. (2005) Clipperton Island: pig sty, rat hole and booby prize. Marine Ornithology, 33:193-194.
BirdLife International (2019) Important Bird Areas factsheet: Clipperton Marine. Downloaded from http://www.birdlife.org on 26/04/2019.