Quetzal abundance in relation to fruit availability in a cloud forest in southeastern Mexico

The Resplendent Quetzal (Pharomachrus mocinno) is an altitudinal migrant th at nests in high elevation cloud forests and migrates toward lower areas du ring the summer rainy season. It has been suggested that its migratory move ments are related to the abundance of ripe Lauraceae fruits. We studied the quetzal diet during two consecutive years, as well as changes in fruit abu ndance of the plant species on which the bird feeds at El Triunfo Biosphere Reserve, southeastern Mexico. The quetzal was observed Feeding on 32 plant species; of these, 24 are new records in its diet. We chose 20 of these 32 species and studied their fruit phenology for two years in order to descri be the relationship between fruit and quetzal abundance. Our results showed that quetzal abundance in the breeding area was correlated with the total number of fruiting species, whereas the correlation between quetzal abundan ce and the number of fruiting Lauraceae species was only marginal. Addition ally, a correlation test showed that quetzal abundance was marginally corre lated with total fruit availability (total no. of fruits per month); howeve r, the correlation between quetzal abundance and the number of fruits in th e Lauraceae was not significant. Our results suggest that the dynamics of f ood resources may be playing a major role in the quetzal's migratory behavi or. Knowing the bird's diet may aid in characterizing the type of habitat a dequate for its conservation. Our observations in this respect suggest that conservation efforts to preserve this bird species should concentrate on t he protection of its habitat, including both breeding and nonbreeding (migr ation) locations.