2025/12/04 by Irene M. Rossell, Dakota C. Herzig, Cathryn H. Greenberg · 1 voice
Environmental Science · #Forest Insect Ecology and Management #Animal Ecology and Behavior Studies #Avian ecology and behavior
paper · doi:10.1080/15594491.2025.2588540
The Yellow-bellied Sapsucker (Sphyrapicus varius) is a migratory woodpecker that forages for sap by drilling holes in live trees and other woody plants. Its nonbreeding range in the USA includes the diverse forests of the southern Appalachian Mountains, where the use of sap trees by sapsuckers has not been previously documented. We investigated sap tree selection by nonbreeding sapsuckers in forested areas of western North Carolina by comparing characteristics of 160 pairs of drilled and nearby (within 10 m) undrilled trees of similar stature. Results showed sapsuckers used 18 out of 24 tree species across eight study sites. We used Ivlev’s electivity index to determine whether sapsuckers exhibited taxonomic preferences based on the proportional use of tree taxa relative to their availability. Results showed neutral use of tuliptree (Liriodendron tulipifera) and maples (Acer spp.); a slight preference for eastern hemlock (Tsuga canadensis), shortleaf pine (Pinus echinata), and several deciduous hardwoods; and varying degrees of avoidance to white pine (Pinus strobus), American beech (Fagus grandifolia), and a few other taxa. Across all sites, trees drilled by sapsuckers (mean ± SD = 55.2 ± 20.2 cm) were significantly larger in diameter than undrilled trees (44.8 ± 16.6 cm), but neither crown loss nor tree type (evergreen conifer or hardwood) had a significant effect on overall tree selection. The generalist feeding strategy of nonbreeding Yellow-bellied Sapsuckers in the diverse forests of this region may buffer them from forest threats and the decline of particular tree species in the landscape.