Evaluation of microtransponder tags on the threatened small-bodied San Marcos Salamander (Eurycea nana)

Abstract

Organism tagging can be used to examine and track important life history data that informs conservation efforts, but mortality and tag loss can mislead management decisions if not properly understood. To conduct mark-recapture studies that benefit conservation of the San Marcos Salamander (Eurycea nana), a tagging method that provides individual identification is needed. The goal of this study was to examine survival and tag retention of San Marcos Salamanders injected with microtransponder tags in captivity to determine if this is an appropriate tagging method. We tagged 23 San Marcos Salamanders with microtransponders at the base of the tail on the left side and monitored the survival daily and tag retention weekly for six months. We compared tagged salamander survival to that of 16 control salamanders. San Marcos Salamander survival (87%) was not affected by tagging. Additionally, no tag loss occurred in this study. Microtransponder tags provided high survival and retention and allowed for individual identification. This is a suitable tagging method for San Marcos Salamanders in captivity and could be considered for field mark recapture studies to examine demographics through individual tracking.