Effective management and conservation of blue-winged teal (Anas discor
s) require information on foods consumed in main wintering areas. We d
escribe foods eaten by 84 blue-winged teal collected in Cienaga Grande
de Santa Marta, Colombia, and Palo Verde Wildlife Refuge, Costa Rica.
The volume of foods found in 12 blue-winged teal collected in Palo Ve
rde in 1982-83 consisted of 92% plant and 8% animal material; cultivat
ed rice predominated. In Cienaga Grande, foods found in blue-winged te
al included 71% plant material during 1979-80 (n = 10) and 91% animal
material (n = 62) in 1985-88 (P < 0.01). Water lily (Nymphaea spp.) se
eds were the most common plant item. Snails (Pyrgophorus spp.) and Cor
ixidae insects were the most prevalent animal items, We suggest that d
ifferences between the 2 Cienaga Grande samples were due to food avail
ability changes produced by gradually increasing salinity levels affec
ting the area. We found no differences between sexes in the proportion
s of plant (P = 0. 755) or animal foods consumed (P = 0.544). Their om
nivorous diet enables blue-winged teal to use a variety of wetlands du
ring winter and to adapt to seasonally varying conditions in wetlands.