Gekkonid field studies are hampered by the difficulty to individually recognize individuals. In this study we assess the feasibility of using their variegated iris pattern to photo-identify Tarentola boettgeri bischoffi, a threatened Macaronesian endemic. Using a library of 924 photos taken over a 9-month period we also evaluate the use of the pattern matching software Interactive Individual Identification System (I 3 S) to match photos of known specimens. Individuals were clearly recognized by their iris pattern with no misidentifications, and using I 3 S lead to a correct identification of 95% of the recaptures in a shorter time than the same process when conducted visually by an observer. The method's feasibility was improved by increasing the number of images of each animal in the library and hindered by photos that deviate from a horizontal angle. Mark-recapture studies typically rely on arti-ficial marks and several marking techniques, from dorsal painting (Salvidio and Oneto, 2008) to the removal of subdigital lamellae (Atzori et al., 2007), heat branding (Vervust and Van Damme, 2009) and toe-clipping (Hare and Cree, 2005), have successfully been used in the study of gekkonid lizards. These methods are difficult to implement in large numbers and can some-times affect the behaviour and even survival of the study animals (Bloch and Irschick, 2004; Reisser et al., 2008). Whenever naturally oc-curring variegated markings are available, pho-tographic identification (photo-ID) constitutes a less intrusive and relatively inexpensive op-tion that has successfully been used on a wide variety of species (Frisch and Hobbs, 2007; Schofield et al., 2008; Angelini, Antonelli and Utzeri, 2010; Ribeiro and Rebelo, 2011; Davies et al., 2013) including geckos with distinctive skin color patterns (Wanger et al., 2009).