Over-summering and migrant Red Knots at Golfo de Santa Clara, Gulf of California, Mexico
191 – 194
1 December 09
Eduardo Soto-Montoya, Roberto Carmona, Martha Gómez, Victor Ayala-Pérez, Nallely Arce, Gustavo D. Danemann
Marine Biology Department, Universidad Autónoma de Baja California Sur, Apartado postal 19-B, La Paz, Baja California Sur, CP 23000, Mexico.
We report the occurrence of Red Knots Calidris canutus on the north-east coast of the Gulf of California, Mexico. Monthly counts were conducted from Jan 2006 to Dec 2008 along a muddy beach at Golfo de Santa Clara, Sonora. An aggregate total of 10,565 Red Knots were recorded, with a maximum count of 1,928 on 25 June 2007. Substantial numbers of over-summering birds occurred consistently in Jun–Jul with varying numbers in Aug, but virtually none from Sep to Dec. Occasional flocks were recorded in Jan–Feb and there was evidence of a small passage in Mar–Apr, but virtually none in May. Thus it seems that the area is used as a stopover in early autumn and spring and that small numbers occur in winter, but its main importance is an over-summering site for immatures that do not go to the breeding grounds. To date no other site has been found to support significant numbers of over-summering Red Knots in the East Pacific flyway.