摘要：Fruits continue to be recognized as an important food source for birds in temperate areas, particularly during the fall migration period. More than 20 species of plants producing fleshy fruits are found in the Arkansas Ozarks. However, only a few of these appear to be important resources for birds during the fall migration period (August - October). Among those are sassafras (Sassafras albidum), gray-backed grape (Vitis cinerea), black cherry (Prunus serotina), hercules club (Araliaspinosa) and pokeweed (Phytolacca americana). Over the past 4 years, we have documented the physical and nutritional characteristics of those fruits and taken observational data on the assemblages of birds eating them. It appears that avian species assemblages feeding on fruits are partially determined by the physical and nutritional contents of those fruits. Sassafras is extremely lipid-rich and higher in caloric content than the other species of fruits. It appears to be eaten almost exclusively by larger birds, perhaps be due to the large size of its fruits, which may exceed gape width of many smaller bird species. Prunus and Vitis are also eaten by a large number of avian species. Phytolacca was eaten only by a small number of primarily resident bird species and often persisted into the winter. Reasons for this pattern are not clear, as it was relatively similar to the other fruits inmost characteristics. Aralia was seen being eaten by only a few species of birds but is less common than the other species, and its small fruits may not be as attractive as those of the other species. Compared to other places in the east, there appear to be a relatively low number of migratory frugivorous birds in northwestern Arkansas. Overall, there were very few species noted at any fruiting plants, and a large proportion of the total assemblage of birds was comprised of resident species.
