MARINE MAMMAL SCIENCE, **(*): ***–*** (*** 2010) C 2010 by the Society for Marine Mammalogy DOI: 10.1111/j.1748-7692.2010.00398.x Risso’s dolphins alter daily resting pattern in response to whale watching at the Azores FLEUR VISSER Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The Netherlands and Nova Atlantis Foundation, Rua dr. A. Freitas Pimentel 11, 9930-309, Santa Cruz das Ribeiras, Pico, Azores, Portugal E-mail:
[email protected] KARIN L. HARTMAN Nova Atlantis Foundation, Rua dr. A. Freitas Pimentel 11, 9930-309, Santa Cruz das Ribeiras, Pico, Azores, Portugal ENTE J. J. ROOD Nova Atlantis Foundation, Rua dr. A. Freitas Pimentel 11, 9930-309, Santa Cruz das Ribeiras, Pico, Azores, Portugal and Zoological Museum, University of Amsterdam, Mauritskade 61, 1092 AD Amsterdam, The Netherlands ARTHUR J. E. HENDRIKS Nova Atlantis Foundation, Rua dr. A. Freitas Pimentel 11, 9930-309, Santa Cruz das Ribeiras, Pico, Azores, Portugal DAAN B. ZULT Department of Psychology, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The Netherlands WIM J. WOLFF Department of Marine Benthic Ecology and Evolution, Groningen University, P. O. Box 14, 9750 AA Haren, The Netherlands 1 2 MARINE MAMMAL SCIENCE, VOL. **, NO. **, 2010 JEF HUISMAN Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Nieuwe Achtergracht 127, 1018 WS Amsterdam, The Netherlands GRAHAM J. PIERCE Oceanlab, University of Aberdeen, Main Street, Newburgh, Aberdeenshire, AB41 6AA, United Kingdom and Instituto Espanol˜ de Oceanografıa,´ Centro Oceanografico´ de Vigo, P. O. Box 1552, 36200 Vigo, Spain ABSTRACT Behavioral responses of Risso’s dolphins (Grampus griseus) to whale watching vessels were studied off Pico Island, Azores.