This U.S.-Chile award will support research collaboration between Mary Willson of the Pacific Northwest Research Station, Juneau, Alaska and J. J. Armesto and M. K. Arroyo-Hurley of the Universidad de Chile in Santiago, Chile. The collaborators intend to quantify the effects of forest fragmentation on mutualistic animals and on the reproduction of their plant mutualists, and to examine the effect of perches on rates of recruitment of fleshy-fruited plants on disturbed sites. Mutualistic interactions between plants and animals comprise a set of major ecological processes in many terrestrial communities, although they are much less studied than competition, predation, parasitism, and herbivory. Because their effects are positive, the continued operation of these mutualisms is critical to maintenance of ecosystems and community function. The proposed work will involve a field census of birds, student training, and setting up a colonization experiment. These studies will prove useful in carrying our similar studies in the north- temperate rain forests from the Pacific part of North America, where communities and interactions may be organized differently.