Effects of Biopsy Sampling on Indo-Pacific Humpback Dolphins (Sousa chinensis) in a Polluted Coastal Environment

2 HongKongDolphinConservationSociety,�P.O.�Box�65457,�TseungKwanOPostOffice,�HongKong Abstract We conducted a biopsy sampling study of Indo- Pacific humpback dolphins (Sousa chinensis) in Hong Kong between October 2004 and January 2006. Humpback dolphins were sampled with a Barnett Ranger RX-150 crossbow. In total, 87 shots were taken at ranges of 8 to 28 m, and 36 tissue samples were collected. The hit rate was 56.3%, and the success rate was 41.4%. There was a better chance of hitting the dolphin with the dart when animals were closer to the shooter (all hits were at < 23 m distance). Humpback dolphin reactions to the procedure were mostly slight, with a few moderate reactions but no extreme ones. Humpback dolphins reacted similarly to hits and misses, and their reaction can best be char- acterized as a startle response. All reactions were short-term, and there was virtually no evidence of long-term impacts on behavior, social organiza- tion, or distribution patterns. Wounds appeared to heal well and were healed over with tissue in < 21 d. When conducted carefully by experienced persons, biopsy sampling of humpback dolphins can be done safely and effectively.