Although primarily frugivores, Toco Toucans also commonly eat insects, and the eggs and nestlings of small or medium-sized birds. Among the fruit consumed by these toucans are figs, oranges, guavas, and peppers. Preferred insects include caterpillars and termites. When they predate nests of other birds, they target those of Yellow-rumped Caciques (Cacicus cela) in particular (Short and Horne 2001) but toucans also prey on the nests of of other species of blackbirds (Icteridae) and of flycatchers (Tyrannidae) (Short and Horne 2002). In captivity, Toco Toucans also eat smaller species of birds that enter the aviary, such as thrashers (Toxostoma sp.), House Sparrow (Passer domesticus), Inca Dove (Columbina inca), Cactus Wren (Campylorhynchus brunneicapillus), and Gambel's Quail (Callipepla gambelii) (Short and Horne 2001).
Little is known about the metabolism of the Toco Toucan. This species can modify the amount of blood flow to its bill and therefore can use its bill as a thermal radiator to distribute heat away from its body (Tattersall et al. 2009). (This does not imply, however, that the extremely large bills of toucans evolved for the purpose of thermoregulation.)