Cooperative Fish and Wildlife Research Units Program: Arizona
Education, Research and Technical Assistance for Managing Our Natural Resources

The narrow-headed gartersnake (Thamnophis rufipunctatus, hereafter THRU) is a federally threatened species endemic to the Mogollon Rim of central Arizona and western New Mexico. This species has undergone marked declines throughout its range due to multiple threats, including the loss or degradation of riparian and within-stream habitat and direct and indirect effects of nonnative fish and crayfish. However, there is relatively little empirical data available on the movement ecology and population dynamics of THRU. Empirical demographic parameter estimates (e.g., survival, abundance) are also important for evaluating site-specific population status and are the building blocks for running population viability analyses. This information allows managers to identify at-risk populations and direct site-specific management actions, thereby aiding in species recovery.

We are studying the ecology THRU along Canyon Creek in central Arizona using mark-recapture surveys and passive PIT tag arrays. The results of this proposed study, when combined with previous studies on THRU, will help us better understand the geographic variation in THRU ecology and increase confidence in management recommendations and status assessments.

The goals of this study are to: (1) conduct three summers of mark-recapture sampling to estimate survival and abundance; and (2) develop and test implantation and field tracking protocols using harmonic transponder tags using a closely related species, the western terrestrial gartersnake, and, conditional upon success of these efforts, implant harmonic transponder tags into juvenile and adult THRU at Canyon Creek to monitor space use and habitat selection.