PRELIMINARY WINTERING COUNTS AND NEW LOCATIONS OF SANDHILL CRANES IN MEXICO

Sandhill cranes (Grus canadensis) undertake a migration twice a year, when more than 400,000 cranes cross the United States from the Arctic of North America and Eastern Siberia to the southwest U.S. and north central Mexico. Although the sandhill crane has been studied intensely, few studies have been done on their Mexican wintering grounds. Little is known about what proportion of the sandhill crane population migrates to Mexico, and there is even less information regarding its dispersion. During winter 2007-2008 we surveyed 30 wetlands in the Chihuahuan Desert ecoregion in northern Mexico, recording presence/absence and number of sandhill cranes. Cranes were present in 53% of the visited sites. In these wetlands we conducted counts at sunset and sunrise up to a total of 67 counts. Crane counts varied between sites with a maximum of 9,000 individuals in northern wetlands and a minimum of 3 individuals in southern wetlands. The majority of wetlands were visited once (73%) while the rest of sites were visited up to 8 times (27%). Cranes were always present in sites visited more than once during the wintering period (December-January). Noteworthy observations of movement and activity patterns were also recorded during the winter. Our data, although preliminary, provide new information regarding wintering locations and dispersion in 6 Mexican estates. Our data also provides the first counts for sandhill cranes in Mexico confirming that the population that migrates to northern Mexico is a large one, revealing new information regarding the ecological needs of the specie