Grantee Research Project Results
Potential Underlying Mechanisms Leading to the Association of Burrowing Owls With AgricultureEPA Grant Number: U915972
Title: Potential Underlying Mechanisms Leading to the Association of Burrowing Owls With Agriculture
Investigators: Moulton, Colleen E.
Institution: Boise State University
EPA Project Officer: Just, Theodore J.
Project Period: January 1, 2001 through October 15, 2003
Project Amount: $65,872
RFA: STAR Graduate Fellowships (2001)
Research Category: Fellowship - Terrestrial Ecology and Ecosystems , Academic Fellowships , Ecological Indicators/Assessment/Restoration
The objective of this research project is to determine the potential factors underlying the association of western burrowing owls (Athene cunicularia hypugaea) with agriculture in southwestern Idaho.Approach:
I examined the availability of suitable nest burrows (burrow-availability hypothesis), abundance of potential prey (prey-availability hypothesis), and predation of nest burrows (predation hypothesis) during the 2001 and 2002 breeding seasons. Nest burrow availability did not differ between agricultural and nonagricultural habitats, and occupancy rates of owls in artificial burrows were greater near agriculture. More rodent-prey species were live trapped in agricultural habitat compared to nonagricultural habitat, but there was no difference in relative abundance of prey between habitat types. Pellet remains indicated a greater abundance and biomass of prey being consumed in agricultural habitat compared to nonagricultural habitat. Finally, predation rates of artificial nests did not differ between habitats. These findings allow me to reject the burrow-availability and predation hypotheses for the association between owls and irrigated agriculture in southwestern Idaho, but the prey-availability hypothesis remains tenable. Thus, burrowing owls may nest near irrigated agriculture because of increased diversity or availability of prey.Supplemental Keywords:
fellowship, burrow-availability hypothesis, prey-availability hypothesis, predation hypothesis, burrowing owls, Athene cunicularia hypugaea, Idaho, ID.