First use of the I3S Pattern photoidentification application as a preliminary and complementary tool for tiger shark Galeocerdo cuvier idenfication

Tiger shark Galeocerdo cuvier (Peròn & Lesueur, 1822) is an apex predator in many tropical and warm-temperate ecosystems around the world (Heithaus, 2001). Its common name derives from the particular dorsal paHern that it’s grey above with vertical black to dark grey bars and spots. Stripes are bold in young but fade in adults (Ebert et al., 2021). This characteristic pattern remains also unvaried when they reach sexual maturity at around 4-13 years (Clua et al., 2013). In addition to this distinctive body pigmentation, tiger sharks can show natural marks and wounds, particularly on their first dorsal fin and body, making this species suitable for the photoidentification approach through the comparison of different pictures, and the obtained data can be used to infer species abundance, surving rates, geographical distribution, and migrations (Marshall & Pierce, 2012). I3S Pattern is an Interactive Individual Identification System (hHp://reijns.com/i3s/) and totally free computer-aided photoidentification application that relies on natural marks to identify individual animals, helping the researcher to extract the body pattern and then compares it against all animals in the database, showing to the researcher the most relevant results. I3S pattern has been first developed just for turtles, but it can now be applied to other animals with particular signs and a recognizable pattern such as tiger sharks.