Patterns of Survival of a Communally Denning Rattlesnake (Crotalus viridis) in a Man-made Hibernacul

Bruckerhoff, Lindsey A.

Division of Biology

Kansas State University

Manhattan, KS USA

Kamees, Larry K

lkkamees@uark.edu

Department of Biological Sciences

University of Arkansas

Fayetteville, AR USA

Holycross, Andrew T.

Department of Biology

Mesa Community College

Mesa, AZ USA Painter, Charles W.

New Mexico Game and Fish

Santa Fe, NM USA

Carpenter, Geoffrey C.

Herptech Metalworks

Bosque Farms, NM USA

Avoiding thermal stress by utilizing hibernacula is fundamental to the survival of snakes occupying temperate environments. Snakes may overwinter alone or aggregate in communal dens to avoid temperature extremes. Limited information is available regarding the denning ecology of pit vipers mainly because of the inaccessibility of snakes in dens, yet basic demographic information is crucial for understanding population dynamics, habitat requirements, and management of pit viper species. Even less is known about the demographics of species and populations utilizing man-made hibernacula which may become increasingly important as habitat becomes more fragmented. The objective of our study was to utilize long-term mark recapture data from Prairie Rattlesnakes (Crotalus viridis) at a man-made hibernaculum to estimate the annual apparent survival rate and investigate factors influencing it. We used multistrata mark-recapture models to estimate encounter rates, apparent survival, and transition rates between states across body condition strata. Over 1,400 captures of 901 individual snakes were made during the course of the eight-year study. Predicted encounter rates varied between males and females and between snakes with different body conditions. The interaction between body size and resident status influenced annual apparent survival rates, with high apparent survival of average sized resident snakes (mean = 0.95 ± 0.12). This study contributes to basic knowledge about population dynamics of communally denning pit vipers and factors influencing their survival.