White-Beaked Dolphin Movements around Iceland: Evidence from Photo-Identification Studies

The white-beaked dolphin (Lagenorhynchus albirostris Gray 1846) is a species of robust dolphin which occurs within the cooler waters of the North Atlantic. The productive waters around Iceland provide an important habitat for this species within their distribution, however very little is known about their utilization of and movements within Icelandic waters. The Húsavík Whale Museum has been collecting photo-identification data of L.albirostris in Skjálfandi Bay for over five years and encouraging other researchers and the public to submit images from other locations in Iceland. In 2004 two images matched well suggesting that they might be the same individual. The two images were compared using the dorsal fin matching software ‘FinEx’ and ‘FinMatch’ developed for the Europhlukes project. FinEx was used to extract the position and relative morphology of dorsal edge marks occurring along the contour line of the dorsal fin. FinMatch was used to compare similarity by comparing each contours features against one another. FinMatch found that the contours and dorsal edge marks extracted for fins shared a match coefficient of 96.63 % similarity. Therefore it was assumed that both images were the same individual because of a result with over 95 percent similarity. The results above indicate that the distribution and movements of L.albirostris around Iceland may be very dynamic. In this study alone the individual featured travels almost half way around the Icelandic coast in a short seven day period. It is suggested that more research and comparative analysis with other research groups on the photo-identification of this species should be conducted in the future. This would allow a greater appreciation of the movements of this species around Iceland but also indicate possible migration trends, identifying how L.albirostris may utilize these productive coastal areas.