The British Herpetological Society

The Herpetological Journal is the Society's prestigious quarterly scientific journal. Articles are listed in Biological Abstracts, Current Awareness in Biological Sciences,Current Contents, Science Citation Index, and Zoological Record.

The 2017/18  impact factor of the Herpetological Journal is 1.268

pdf 02. Telescoping turtles: a comparison of smartphone telephoto magnifiers to non-invasively observe and identify freshwater turtles


Open Access

pp. 143-147

Authors: Javier Escobar, Mark A. Rollins & Shem D. Unger

Abstract: Sampling freshwater turtles using traditional trapping methods can present significant economic investment to researchers. However, collecting baseline data on turtle relative abundance and species presence requires limited investment and can be non-invasive. Recent advances in performance of readily available smartphone cameras enable collection of high quality digital photos of wildlife, accessible to both researchers and citizen scientists. We report on the feasibility of using several low cost and lightweight telephoto lens attachments for smartphones to identify turtles from various observational distances. All three magnifiers provided a reliable, effective method for counting turtles with increased standard image resolution, with the number of basking turtles correctly enumerated and identified increasing with decreasing distance to observers (Spearman rank correlation = -0.719). The most consistently usable images for species identification were taken with 10X at distances under ~15 m and in urban pond settings where individuals are potentially less easily startled or where ambient noise is common. Ultimately, these magnifiers can be successfully incorporated into university outdoor biological laboratories, undergraduate research and community citizen science programs.

Key words: conservation, Trachemys, emydidae, freshwater ecology, survey techniques

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