Movements of Two Satellite-tagged Pygmy Killer Whales (Feresa attenuata) Off the Island of Hawaii

摘要

Pygmy killer whales (Feresa attenuata) are a rare tropical oceanic odontocete that are normally found close to shore only around oceanic islands (Donahue and Perryman 2009, McSweeney et al. 2009). In the Exclusive Economic Zone (EEZ) surrounding the Hawaiian Islands there is a single stock of pygmy killer whales recognized (Carretta et al. 2010). In the Hawaiian EEZ they are the third-least abundant of the 12 species of delphinids documented, with an estimated abundance of 956 individuals (CV = 0.83; Barlow 2006). Around the island of Hawai i a long-term photoidentification study has identified a small population that exhibits high site fidelity (McSweeney et al. 2009). This species is encountered only infrequently (an average of once every 35 d on the water), and thus limited information is available to examine movements based on location records of photo-identified individuals. Only a small number of identification photos have been available from other islands in the main Hawaiian Islands so there has been little ability to assess movements among islands.