PARENT SESSION
Poster Session 25: Mammalian Ecology
Thursday, August 11, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal
Bat use of Ozark forests: The effect of forest structure and fragmentation.
Yates, Mark*,1, Muzika, Rose- Marie1, 1 University of Missouri, Columbia, MO, USA
ABSTRACT- Concern over conservation of bats has led to increased interest and research into factors that influence the distribution and composition of local bat communities. As forest landscapes are increasingly altered through fragmentation, describing and quantifying ecological variables that influence bat use of forests becomes increasingly critical for conservation objectives. Furthermore, the influences are likely to change over spatial scales. The objective of this study was to determine habitat characteristics associated with bat species composition within a forested landscape at three different spatial scales: site, patch and landscape. Sample points were placed in upland deciduous forests and mixed pine hardwood forests in 2 watersheds in the Ozark highlands of southeastern Missouri. Each location was surveyed for bat species composition using Anabat II acoustic detection systems and calls were analyzed using Analook software. Echolocation calls were identified to species using discriminate function analysis (Britzke 2003). Forest structure characteristics and plant compositional data were collected at each site. Patch and landscape characteristics were determined from remotely sensed data using a 12-class cover type classification. FRAGSTATS software was used to calculate patch and landscape metrics. Bat call and habitat characteristics data were used to estimate occupancy rates following methods described by MacKenzie et al. (2003). Akaike Information Criteria was used to select models predicting site occupancy by bat species. Results presented here include the five most commonly detected bat species - Eastern pipistrelle, red bat, northern long-eared bat, gray bat and Indiana bat. Aspect and roosting habitat variables affected Pipistrelle bat activity. Distribution of red bats in the landscape appeared to be random. Models describing northern long eared bat prevalence were related to openness of forest and roosting habitat. Models selected for gray bat distribution focused on variables affecting navigation in forests. Indiana bats were influenced most by aspect. Response of bats to forest structure, fragmentation and arrangement is species specific. Implications of models can be used to assist in formulation of management plans at multiple scales.
Key words: bats, forest fragmentation, acoustic detection