University Presentation Showcase: Undergraduate Division
Home range and habitat use of breeding Brown Thrashers
Presenter Hometown
Paintsville, KY
Major
Wildlife Management
Department
Biological Sciences
Degree
Undergraduate
Mentor
David R. Brown
Mentor Department
Biological Sciences
Recommended Citation
Castle, Joshua, "Home range and habitat use of breeding Brown Thrashers" (2021). University Presentation Showcase Event. 26.
https://encompass.eku.edu/swps/2021/undergraduate/26
Abstract
Across North America, habitat loss has led to declines in songbird populations, including Brown Thrashers (Toxostoma rufum), a common species in Kentucky. The objective of this study was to test the effects of land cover dominated by invasive shrubs on the home ranges and nesting locations of breeding Brown Thrashers. The study area, Taylor Fork Ecological Area in Madison County, KY, is dominated by shrub and early-successional habitat. By locating nests and tracking individuals throughout the breeding season, we sought to identify a preference between native and exotic plants and whether this impacted nesting success and home range use. Vegetation data were collected within 5-meter radius plots around each nest found and at random locations to compare habitat use with habitat availability. Of 15 nests, 14 were in invasive shrubs, even though native shrubs were available, and young fledged from 11 of 15 nests. Eight of 18 captured Brown Thrashers were fitted with radio transmitters for tracking. Home ranges were measured with kernel analysis at 80% and 45% contours using Program R. To determine home range vegetation composition, the home range contours were superimposed on a land cover classification using ArcMap. Given the disproportionate use of invasive shrubs as a nesting substrate and the high occurrence of nest success, we suggest it may be beneficial to some species to maintain some stands of exotic vegetation until native substrates are established through restoration.
Presentation format
Poster
Home range and habitat use of breeding Brown Thrashers
Across North America, habitat loss has led to declines in songbird populations, including Brown Thrashers (Toxostoma rufum), a common species in Kentucky. The objective of this study was to test the effects of land cover dominated by invasive shrubs on the home ranges and nesting locations of breeding Brown Thrashers. The study area, Taylor Fork Ecological Area in Madison County, KY, is dominated by shrub and early-successional habitat. By locating nests and tracking individuals throughout the breeding season, we sought to identify a preference between native and exotic plants and whether this impacted nesting success and home range use. Vegetation data were collected within 5-meter radius plots around each nest found and at random locations to compare habitat use with habitat availability. Of 15 nests, 14 were in invasive shrubs, even though native shrubs were available, and young fledged from 11 of 15 nests. Eight of 18 captured Brown Thrashers were fitted with radio transmitters for tracking. Home ranges were measured with kernel analysis at 80% and 45% contours using Program R. To determine home range vegetation composition, the home range contours were superimposed on a land cover classification using ArcMap. Given the disproportionate use of invasive shrubs as a nesting substrate and the high occurrence of nest success, we suggest it may be beneficial to some species to maintain some stands of exotic vegetation until native substrates are established through restoration.
