Spatial and temporal variation in fruit use by wildlife in a forested landscape

Abstract

We monitored production and removal rates of fruit from 22 common plant species over 2 years in five habitats of a managed landscape in South Carolina (USA). Our long-term goal is to determine the importance of fruit as a resource for vertebrates and to provide recommendations for management of key species and habitats. This study lays the foundation for that goal by documenting fruit production and availability, variation in use by wildlife, and how these factors vary by plant species, habitat, and season. Six species produced >1 kg dry mass of pulp per hectare per year. Vertebrates consumed ≥50% of fruits in 17 of the 22 plant species. Fruit loss to insects and microbes was generally small and varied significantly among seasons, being lowest in fall and winter. The length of time ripe fruit survived on plants varied among species from 3 to 165 days. Survival time of fruits did not vary significantly among habitats but was significantly shorter in the summer than in fall or winter. Approximately, half the species produced fruit in the fall and winter and these fruits were primarily consumed by over-wintering wildlife. This pattern is inconsistent with the general belief that fruit production in the eastern United States is timed to correspond with periods of high bird abundance during fall migration. Production and consumption of winter fruits deserves further attention from forest managers, as relatively little other food is available in winter, energy demands of over-wintering birds are high, and current management practices often reduce fruit availability of key species (e.g., Myrica cerifera). We suggest that fruit is more important than generally realized in maintaining vertebrate diversity in temperate forests and that the focus of managers on hard mast production should be broadened to include fruiting plants.