The Black-bellied Whistling-Duck (Dendrocygna autumnalis) ranges from the southern United States to northwestern Peru, Argentina, and Brazil, occupying lakes and shallow freshwater marshes in the tropical and subtropical zones (A.O.U. 1998). It is a largely nocturnal species that often forms small groups, nests at heights of up to 3 m in large trees, and feeds on aquatic plants, cultivated grains, and seeds (Alsop 2001). Although the species is generally nonmigratory, extralimital records (some of which probably involve escapees) are scattered across the United States to southern Canada, as well as parts of Mexico outside of the normal range (James and Thompson 2001). The Baja California Peninsula is not part of the Black-bellied Whistling-Duck’s historical range (Grinnell 1928, Wilbur 1987), but Howell and Webb (1992) reported one at San José del Cabo in June 1999, Carmona et al. (1999) reported four at Lagunas de Chametla, within the city of La Paz (11 and 12 December 1997; 14 February and 4 March 1998), and Erickson et al. (2001) reported additional sightings at both locations from 1992 to 1998. This paper updates the species’ status in La Paz since that time and documents the first breeding records for the peninsula.