skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

This content will become publicly available on April 8, 2020

Title: Effects of group size and group density on trade–offs in resource selection by a group–territorial central–place foraging woodpecker

Abstract

Trade-offs in resource selection by central-place foragers are driven by the need to balance the benefits of selecting resources against the costs of travel from the central place. For group-territorial central-place foraging birds, trade-offs in resource selection are likely to be complicated by a competitive advantage for larger groups at high group density that may limit accessibility of high-quality distant resources to small groups. We used the group-territorial, central-place foraging Red-cockaded Woodpecker Leuconotopicus borealis (RCW) as a case study to test predictions that increases in group density lead to differences in foraging distances and resource selection for groups of different sizes. We used GPS tracking and LiDAR-derived habitat data to model effects of group size on foraging distances and selection for high-quality pines (≥ 35.6 cm diameter at breast height (dbh)) and lower quality pines (25.4–35.6 cm dbh) by RCW groups across low ( n = 14), moderate ( n = 10) and high group density ( n = 10) conditions. At low and moderate group density, all RCW groups selected distant high-quality pines in addition to those near the central place because competition for resources was low. In contrast, at high group density, larger groups travelled further to selectmore » high-quality pines, whereas smaller groups selected high-quality pines only when they were close to the central place and, conversely, were more likely to select lower quality pines at greater distances from the central place. Selection for high-quality pines only when close to the cavity tree cluster at high group density is important to long-term fitness of small RCW groups because it allows them to maximize benefits from both territorial defence and selecting high-quality resources while minimizing costs of competition. Furthermore these relationships suggest that intraspecific competition at high group density entails substantive costs to smaller groups of territorial central-place foragers by limiting accessibility of distant high-quality foraging resources.« less

Authors:
ORCiD logo [1];  [1];  [1];  [2]
  1. North Carolina State Univ., Raleigh, NC (United States)
  2. USDA Forest Service Savannah River, New Ellenton, SC (United States)
Publication Date:
Research Org.:
USDA Forest Service-Savannah River, New Ellenton, SC (United States)
Sponsoring Org.:
USDOE Office of Environmental Management (EM), Acquisition and Project Management (EM-50)
Contributing Org.:
USDA Forest Service-Savannah River
OSTI Identifier:
1512253
Report Number(s):
19-03-P
Journal ID: ISSN 0019-1019; 19-03-P
Grant/Contract Number:  
EM0003622
Resource Type:
Accepted Manuscript
Journal Name:
IBIS
Additional Journal Information:
Journal Issue: 2019; Journal ID: ISSN 0019-1019
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; competition; density dependence; endangered species; forest structure; functional; response; LiDAR; Red-cockaded Woodpecker; space use

Citation Formats

Garabedian, James E., Moorman, Christopher E., Peterson, M. Nils, and Kilgo, John C. Effects of group size and group density on trade–offs in resource selection by a group–territorial central–place foraging woodpecker. United States: N. p., 2019. Web. doi:10.1111/ibi.12733.
Garabedian, James E., Moorman, Christopher E., Peterson, M. Nils, & Kilgo, John C. Effects of group size and group density on trade–offs in resource selection by a group–territorial central–place foraging woodpecker. United States. doi:10.1111/ibi.12733.
Garabedian, James E., Moorman, Christopher E., Peterson, M. Nils, and Kilgo, John C. Mon . "Effects of group size and group density on trade–offs in resource selection by a group–territorial central–place foraging woodpecker". United States. doi:10.1111/ibi.12733.
@article{osti_1512253,
title = {Effects of group size and group density on trade–offs in resource selection by a group–territorial central–place foraging woodpecker},
author = {Garabedian, James E. and Moorman, Christopher E. and Peterson, M. Nils and Kilgo, John C.},
abstractNote = {Trade-offs in resource selection by central-place foragers are driven by the need to balance the benefits of selecting resources against the costs of travel from the central place. For group-territorial central-place foraging birds, trade-offs in resource selection are likely to be complicated by a competitive advantage for larger groups at high group density that may limit accessibility of high-quality distant resources to small groups. We used the group-territorial, central-place foraging Red-cockaded Woodpecker Leuconotopicus borealis (RCW) as a case study to test predictions that increases in group density lead to differences in foraging distances and resource selection for groups of different sizes. We used GPS tracking and LiDAR-derived habitat data to model effects of group size on foraging distances and selection for high-quality pines (≥ 35.6 cm diameter at breast height (dbh)) and lower quality pines (25.4–35.6 cm dbh) by RCW groups across low (n = 14), moderate (n = 10) and high group density (n = 10) conditions. At low and moderate group density, all RCW groups selected distant high-quality pines in addition to those near the central place because competition for resources was low. In contrast, at high group density, larger groups travelled further to select high-quality pines, whereas smaller groups selected high-quality pines only when they were close to the central place and, conversely, were more likely to select lower quality pines at greater distances from the central place. Selection for high-quality pines only when close to the cavity tree cluster at high group density is important to long-term fitness of small RCW groups because it allows them to maximize benefits from both territorial defence and selecting high-quality resources while minimizing costs of competition. Furthermore these relationships suggest that intraspecific competition at high group density entails substantive costs to smaller groups of territorial central-place foragers by limiting accessibility of distant high-quality foraging resources.},
doi = {10.1111/ibi.12733},
journal = {IBIS},
number = 2019,
volume = ,
place = {United States},
year = {2019},
month = {4}
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on April 8, 2020
Publisher's Version of Record

Save / Share: