McMurray, C., Allen, N., Hook, S. et al. 2018. I3S software as a refinement technique to identify individuals within a captive Scyliorhinus canula population. Animal Technology and Welfare 17(3), 204-205 (IAT Congress 2018 Poster Presentation).

Demarking individual animals within a group is often required in research. However, the process of invasive tagging induces stress and if a tag becomes detached it may wound the animal and/or prevent identification. Photo identification using natural marks can be an alternative strategy. It is relatively cheap and should induce minimum stress and/or damage therefore improving the welfare of the animal. Thus video recognition has the potential to be a refinement of current tagging methods for aquatic organisms. I3S is a free computer aided photo-identification application that relies on natural marks to identify animals. The user will manually point out the most distinguishing features using reference points which are stored in a database. When this step is completed, subsequent images can be searched against these reference points automatically to determine the match. We tested the utility of this software for recognising individuals within a captive population of catsharks over 14 weeks of development post-hatch. Individuals should be photographed every week until the major markings become available as the software recognises individuals more successfully when the sharks are older. This technique may also be applied to other aquatic models such as zebrafish and Xenopus, replacing invasive tagging.