MARINE MAMMAL SCIENCE, 24(3): 535–553 (July 2008) C  2008 by the Society for Marine Mammalogy DOI: 10.1111/j.1748-7692.2008.00201.x Site fidelity and association patterns in a deep-water dolphin: Rough-toothed dolphins (Steno bredanensis) in the Hawaiian Archipelago ROBIN W. BAIRD Cascadia Research Collective, 218 1 / 2 West 4th Avenue, Olympia, Washington 98501, U.S.A. E-mail: rwbaird@cascadiaresearch.org DANIEL L. WEBSTER Wild Whale Research Foundation, P. O. Box 139, Holualoa, Hawai‘i 96725, U.S.A. SABRE D. MAHAFFY Cascadia Research Collective, 218 1 / 2 West 4th Avenue, Olympia, Washington 98501, U.S.A. and Wild Whale Research Foundation, P. O. Box 139, Holualoa, Hawai‘i 96725, U.S.A. DANIEL J. MCSWEENEY Wild Whale Research Foundation, P. O. Box 139, Holualoa, Hawai‘i 96725, U.S.A. GREGORY S. SCHORR Cascadia Research Collective, 218 1 / 2 West 4th Avenue, Olympia, Washington 98501, U.S.A. ALLAN D. LIGON Wild Whale Research Foundation, P. O. Box 139, Holualoa, Hawai‘i 96725, U.S.A. ABSTRACT In the Pacific, rough-toothed dolphins (Steno bredanensis) are typically found in the open ocean and in deep waters around oceanic islands. We examined habitat use, site fidelity, movements, and association patterns of this species in the main 535