Searching for the condors' next home.

Searching for the condors' next home

Now that scientists have captured all of the wild California condors, in hopes that the endangered birds will prosper and multiply in captivity (SN: 4/25/87, p.263), some researchers are turning their attention toward the habitat to which the condors may someday return. Geographers Frank Davis and Joseph Scepan of the University of California at Santa Barbara and Linda L. Blum of the National Audubon Society, who is working in the U.S. Fish and Wildlife Service's Ventura, Calif., office, are developing a habitat database that may help them understand the environmental factors important to the species' survival in the wild.

Using a computerized mapping system, the researchers are able to search for relationships between the 15-year-old record of condor sightings and environmental variables such as terrain, vegetation and land use. Davis argues that instead of releasing the condors where the last wild ones were found--as was once proposed--the computer system, suitably updated with changes in land use, could be used to determine the best spots for the condors' return to the wild. Land-use changes are particularly important to the birds' ability to forage; cow- and game-containing rangeland in parts of California is being converted--at a rate as high as 21,000 acres per year--to irrigated agricultural and residential property, according to the researchers. Their database may also provide environmental clues to the birds' decline.

Davis says that no one had tried before to systematically link changes in distribution of the past 15,000 condor sightings with geographic and ecological information because the ability to display that large amount of data geographically had been crude at best. But with the advances in computer mapping in the last decade, he says, this and many other applications are becoming possible.