MARINE MAMMAL SCIENCE, 22(2): 240–260 (April 2006) C  2006 by the Society for Marine Mammalogy DOI: 10.1111/j.1748-7692.2006.00031.x REACTIONS OF CAPTIVE HARBOR PORPOISES (PHOCOENA PHOCOENA) TO PINGER-LIKE SOUNDS JONAS TEILMANN JAKOB TOUGAARD Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark and National Environmental Research Institute, Department of Arctic Environment, Frederiksborgvej 399, DK-4000 Roskilde, Denmark E-mail: jte@dmu.dk LEE A. MILLER Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark TIM KIRKETERP Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark and University of Southern Denmark, IT-Department, Winsløwparken 17.1, DK-5000 Odense C, Denmark KIRSTIN HANSEN 1 SABRINA BRANDO 2 Fjord & Bælt, Margrethes Plads 1, DK-5300 Kerteminde, Denmark ABSTRACT Pingers on gill nets can reduce bycatch of harbor porpoises. If harbor porpoises habituate to pingers, the effect may be reduced or lost. Two captive harbor porpoises were exposed to three sound types. All sounds were in the frequency band from 100 kHz to 140 kHz, 200 ms long, and presented once per 4 s. The source level was 153 dB re 1 Pa RMS at 1 m. Each session consisted of a 10-min presound, a 5-min sound, and a 10-min postsound period. Behavior was recorded on video and on dataloggers placed on the dorsal fin of one animal. The loggers recorded heart rate, swimming speed, dive duration, and depth. The animals responded most strongly 1 Current address: Odense Zoo, Sdr. Boulevard 306, DK 5000 Odense C, Denmark. 2 Current address: Sea Mammal Research Unit, Gatty Marine Laboratory, St. Andrews, Fife KY16 8LB, Scotland. 240