Shorebird counts in the Upper Bay of Panama highlight the importance of this key site and the need to improve its protection

Shorebirds are among the most migratory of all birds and spend the majority of the year in a small number of essential wintering and migratory staging areas. As these birds take no notice of political borders, their conservation represents an international challenge (Myers 1983, Myers et al. 1987, Morrison & Myers 1989), one whose importance is emphasized by recent declines in North American shorebird populations (Donaldson et al. 2000, Morrison et al. 2001). Panama occupies an important geographical position connecting North and South America and, because of suitable intertidal habitats on its coasts, hosts a large number of migratory shorebirds in a restricted area. Aerial surveys by the Canadian Wildlife Service have documented the importance of Panama as a wintering and staging area for these birds (Morrison et al. 1998). In January 1993, they counted 255,000 shorebirds in the whole country of which 80% were in the Upper Bay of Panama. These numbers, concentrated in a small area and representing nearly 10% of the wintering populations of the whole of South America, highlight the crucial importance of Panama for shorebirds. During southward migration in October 1991, counts were even higher with over 369,000 shorebirds in the Upper Bay alone (Morrison et al. 1998). Aerial and ground surveys by Watts (1998) found 370,000 shorebirds in a single day during fall migration in 1997. These numbers, by exceeding 100,000 birds regularly, qualify the area as an International Reserve under the Western Hemisphere Shorebird Reserve Network (WHSRN) (Morrison et al. 1995). Taking turnover into account, Watts (1998) estimated that about 1.1 million Western Sandpipers alone pass through the area during fall migraShorebird counts in the Upper Bay of Panama highlight the importance of this key site and the need to improve its protection