Document: JIM-3-45-8

Phenology and physical traits of bird-dispersed fruits in middle Georgia.

FERRARI, J.B.*

Wesleyan College, Macon, GA 31210 USA ¹

Abstract:
Fruit characteristics of 100 species of trees, shrubs, and vines were studied in a middle Georgia forest to understand their relationships to frugivorous birds. Phenological data were used to categorize species as fruiting in summer, fall, fall/winter, or winter. Twenty fruits of each of 36 species were weighed and measured and the number of seeds per fruit, seed mass, and percent pulp were determined. Of 100 species, 41% were bird dispersed and a total of 65% were animal dispersed. The frequency of bird dispersal is higher than at northern latitudes, occurring in 27% of trees, 54% of shrubs, and 63% of vines. Prevalent colors of fleshy fruits were black, purple, or blue (54%), followed by red or orange (26%). Median values for fruit mass, diameter, and percent pulp were 230 mg, 7.6 mm, and 76%. The fall/winter and winter fruiting strategies were significantly associated with the evergreen growth form; only 6% of summer and fall fruiting species were evergreen versus 60% of fall/winter and winter fruiting species. Peak fruit availability occurred in late November, when 30 species were in fruit, and continued into January. Peak fruit availability is thus after the peak species richness of migrant frugivorous birds in September and October. More persistent fruiting into winter relative to northern latitudes is likely related to the overwintering of many frugivorous bird species in the southern United States.

Keywords: phenology, fruit, frugivory, Georgia, bird

This abstract is being presented at: 10:30 AM in session:
DISPERSAL