Exploitation of Erythrina dominguezii Hassl. (Fabaceae) nectar by perching birds in a dry forest in western Brazil.

Among the vertebrate pollinated plants, the genus Erythrina includes tree species in which birds are the pollen vectors. Two groups in this genus may be distinguished: a) the hummingbird, and b) the perching bird pollinated species. Erythrina dominguezii is included in the second group and occurs in deciduous/semi-deciduous forests in the southwestern neotropics. I studied the exploitation of Erythrina dominguezii nectar by perching birds in a dry forest in western Brazil. Six perching bird species from two distinct groups (Psittacidae: Brotogeris chiriri, Nandayus nenday, Aratinga acuticaudata; Icterinae: Psarocolius decumanus, Icterus cayanensis, I. icterus) consumed its nectar. The two most important consumers were Brotogeris chiriri (51.5% of the flowers visited by birds) and Psarocolius decumanus (20%). While B. chiriri was a flower predator, P. decumanus removed the nectar without damaging the flowers which it opened by inserting its large bill between the standard and the keel. Nandayus nenday, Aratinga acuticaudata, and I. icterus exploited the nectar like P. decumanus, and presumably also contributed to pollen transfer. As the flowering in E. dominguezii was intense and synchronous during the dryest period of the year, and its nectar was highly consumed by birds, the present data suggest that the nectar of this species may be important as an alternative resource to frugivorous/omnivorous birds when other resources are scarce.