Distribution and abundance of shorebirds in the coastal wetlands of the Yucatan Peninsula, Mexico

Although it has long been known that large numbers of shorebirds occur on passage and in winter on the Yucatan Peninsula, Mexico, quantitative information has been lacking and is needed to guide management of the wetlands in the region. Aerial and ground counts of shorebirds were therefore conducted from October 2004 to January 2006 in order to locate and assess the size of shorebird concentrations and to investigate to what extent the coastal wetlands of the NW Yucatan Peninsula are used by resident and migratory shorebirds. Peak counts for the region per season were 37,911 shorebirds in winter 2004 and 26,818 in fall 2006 and the aggregate non-breeding season peak count was 51,058 shorebirds in 2005–2006. The most  abundant shorebirds were: Western Sandpiper Calidris mauri (32.3% of the aggregate total), dowitchers Limnodromus spp. (16.1%), Least Sandpiper C. minutilla (16.1%), Sanderling C. alba (7.8%), and yellowlegs Tringa spp. (6.6%), which together comprised 79% of all shorebirds identified. Compared with other sites on the Gulf Coast of Mexico, the Yucatan Peninsula region is only second in importance after the Laguna Madre complex. The area qualifies as a site of regional importance within the Western Hemisphere Shorebird Reserve Network.