Predicting minimum habitat requirements of the Indiana bat in the Champlain
Valley, Vermont and New York.
Principal Investigator: Therese Donovan
Graduate Student: Kristen
Predicting potential habitat across a landscape is extremely
challenging for rare species. Analyzing
habitat requirements using partitioned Mahalanobis D2
methods avoid pitfalls commonly encountered when surveying elusive
species that typically have small sample sizes and low detection
probabilities because it is based solely on data collected at known
species locations. Minimum
habitat requirements are determined by examining a principal
components analysis to determine habitat characteristics that are
consistent across known locations.
The goals of this study were to (1) document and compare the
minimum habitat requirements of
bats (Myotis sodalis) in the
across 7 spatial scales and (2) map potential habitat for the
species throughout the same area.
We radio-tracked 24 female Indiana bats to their roost trees
and across their nighttime foraging areas, and collected habitat
characteristics at 7 spatial scales: 1) roost trees, 2) 0.1 ha
circular plots surrounding the roost trees, 3) home ranges, and 4-7)
0.5 km, 1 km, 2 km, and 3 km buffers surrounding the roost tree.
Fifty roost trees were identified and found to be tall, large
diameter trees with exfoliating bark, located typically at low
elevations and close to water. Trees
in the plots surrounding roost trees were typically smaller in dbh,
shorter in height, and healthier than the central roost trees.
Fourteen home ranges were found to be in areas of diverse,
patchy land cover types that were close to water, with an
east-facing aspect. Across
all landscape extents, the total area of forest within roost tree
buffers and the aspect across those buffers were the two most
consistent features. Predictive
maps indicated that suitable habitat ranged from 4.7% to 8.1% of the
total area examined depending upon the number of components used,
and was distributed throughout the
information is needed on birth and survival rates to assess habitat
quality in the region.
||Click here for
a project brochure.
||Watrous, K., T.
Donovan, R. Mickey, S. Darling, A. Hicks, S. Von Oettingen.
2006. Predicting minimum habitat characteristics for the Indiana bat
in the Champlain Valley. Journal of Wildlife Management
||Watrous, K. 2006. Predicting minimum habitat characteristics
of the Indiana bat (Myotis sodalis) in the Champlain Valley of Vermont and
New York. MS Thesis, University of Vermont, Burlington, Vermont USA.