Skip to main content
U.S. flag

An official website of the United States government

Habitat preferences of foraging red-cockaded woodpeckers at the Savannah River Site, South Carolina

Informally Refereed

Abstract

I conducted a foraging study to examine habitat use of red-cockaded woodpeckers at the Savannah River Site, South Carolina. Because much of the land had been harvested in the late 1940s and early 1950s prior to being sold to the Department of Energy, the available habitat largely consisted of younger trees (e.g., less than 40 years old). From 1992 to 1995, I examined the foraging behavior and reproductive success of 7 groups of red-cockaded woodpeckers. Availability of pines of various age classes (<20,20-29, 30-39, and ≥40 years old) and size classes (<20.3,20.3-25.4, ≥25.4 cm dbh; <8,8-10, ≥10 in, respectively) was estimated from extensive vegetation sampling (n = 14,713 trees) within 800 m (2,640 ft) of the nest trees of each of the 7 groups. I compared habitat availability to actual foraging use of the trees. A total of 6,284 foraging observations was taken during all seasons of the year and at all times of day. Birds in all 7 groups foraged selectively with respect to tree age. Birds in each group preferred to forage in trees that were ≥30 years in age and displayed even stronger preferences for trees ≥40 years in age. On the basis of availability, it was predicted that 24.5% of the foraging observations of all groups combined would occur in trees with the largest size class (dbh ≥25.4 cm). However, that size class contained 66.9% of the total foraging observations. Birds in all 7 groups foraged selectively with respect to tree size, and selected the medium (20.3-25.4 cm dbh) and largest (≥25.4 cm dbh) size classes. Reproductive success tended to increase with an increase in number of pine stems ≥25.4 cm dbh within 800 m of the nest cavity.

Keywords

Age class, availability, diameter at breast height, foraging, habitat preferences, habitat use, Savannah River Site, South Carolina

Citation

Franzreb, Kathleen E. 2004. Habitat preferences of foraging red-cockaded woodpeckers at the Savannah River Site, South Carolina. In: Costa, Ralph; Daniels, Susan J., eds. Red-cockaded woodpecker: Road to recovery. Blaine, WA: Hancock House Publishers: 553-561.
https://www.fs.usda.gov/research/treesearch/20525