Conservationists may be overestimating wildlife habitat

New Scientist: The devil is certainly in the detail when it comes to planning sanctuaries for plants and animals in the wild. The amount of land available may well be less than we imagine because the scale of existing models is too large. At present, most models divide the world into 50-kilometre grid squares, which gives a very coarse resolution.

Changwan Seo of the University of Seoul, South Korea, and his colleagues tested four models at a variety of spatial scales, using existing data for rare plants such as Coulter pine. The larger the grid size, the more the models overestimated the range available, the team found. Within grid sizes of more than 16 by 16 kilometres, in areas like the eastern Sierra Nevada in California, conservationists overestimate the amount of habitat available to a species by two or three times (Biology Letters, DOI: 10.1098/rsbl.2008.0476).

Conservationists will have to run models with smaller grid sizes, even though this costs more and consumes more computer time, says Lee Hannah of Conservation International in Santa Barbara, California, who co-authored the paper.

Image from that science fiction touchstone, The Incredible Shrinking Man. I hope Universal doesn't send a squadron of lawyers after me for using this photo.