Cheap and accessible method to aid individual photo-identification of grey seals, Halichoerus grypus

摘要: A method was developed to assist in the photo-identification of individual grey seals ( Halichoerus grypus ). Fixed reference points eye and ear were used define a rectangular area pelage on seal's head, termed identifier patch (IP). Extracted IPs converted binary masks, percentage black pixelation within each mask evaluated. Multiple images same head profile gave masks with similar patterns (mean standard deviation 3.3% (±1.6%)). The low level ‘within seal’ variability enabled ‘between be separated basis pixelation. Subsequent matching achieved by using pattern complete identification process. Successful seal images, collected two years nine months apart, at North Wales field site accomplished this method. Pattern-matching trials 88 untrained volunteers showed extracted white superior visual cue for separating compared straightforward inspection photographs. All identified greater number correct matches mask-matching This shows promise providing cheap accessible system order search image databases.