Migration patterns in a population of cottonmouths (Agkistrodon piscivorus) inhabiting an isolated wetland
X. Glaudas*, K. M. Andrews1, J. D. Willson1, and J. W. Gibbons
University
of Georgia's Savannah River Ecology Laboratory, Aiken, SC, USA
Abstract
Few studies have examined the spatial and temporal migration patterns
of snakes to and from active-season habitats. We conducted a year-long
population-level analysis of cottonmouth Agkistrodon piscivorus
migration patterns by monitoring snakes entering and leaving a Carolina
bay wetland that was encircled by a continuous terrestrial drift fence.
Cottonmouths used the wetland during the active season and left the bay
in the fall to overwinter in other habitats. Adults and juveniles did
not differ in time of arrival at the bay but juveniles left the bay earlier
than adults. Spatially, captures of adult cottonmouths entering and leaving
the bay were distributed non-randomly, with capture peaks corresponding
to the directions to the nearest permanent aquatic habitats. Juveniles'
immigration patterns in the spring were biased in the same directions
as those of the adults, but they left non-directionally in the fall. This
suggests that neonates do not rely on adult scent trailing to locate hibernacula,
and that in a region with moderate winter temperatures, suitable overwintering
sites may not be a limited resource. Additionally, our study demonstrates
that cottonmouths make extensive use of upland habitats and underscores
the importance of both critical upland habitat and forested corridors
between wetlands and hibernacula for the conservation of wetlands herpetofauna.
* Correspondence
X. Glaudas.
Current address: Department of Biological Sciences, University of Nevada,
4505 Maryland Parkway, Las Vegas, NV 89154, USA.
Tel: (702) 895-5294
Fax: (702) 895-3956
Email: glaudasx@unlv.nevada.edu
SREL Reprint #3010
Glaudas, X., K. M. Andrews, J. D. Willson and J. W. Gibbons. 2007. Migration patterns in a population of cottonmouths (Agkistrodon piscivorus) inhabiting an isolated wetland. Journal of Zoology 271:119-124.
