Migration patterns in a population of cottonmouths (Agkistrodon piscivorus) inhabiting an isolated wetland

• Published in: Journal of zoology (1987) 2007-02, Vol.271 (2), p.119-124
• Main Authors: Glaudas, X, Andrews, K.M, Willson, J.D, Gibbons, J.W
• Format: Article
• Language: English
• Subjects: activity; Agkistrodon piscivorus; Animal migration; Animal populations; Habitats; Hibernation; migration; movement patterns; reptile; reptiles; snake; Snakes; Wetlands
• ISSN: 0952-8369; 1469-7998
• DOI: 10.1111/j.1469-7998.2006.00232.x

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.