Odontocete Movements off the Island of Kaua‘i: Results of Satellite Tagging and Photo-Identification Efforts in January 2012

There are 18 species of odontocetes that may be found around the islands of Kaua‘i and Ni‘ihau. Using individual photo-identification and genetic analyses of biopsy samples, previous
small-boat-based field efforts off Kaua‘i and Ni‘ihau have provided evidence of a demographically-isolated resident population of common bottlenose dolphins (Tursiops truncatus) off the islands (Baird et al. 2009; Martien et al. 2011), and a high-degree of site fidelity by rough-toothed dolphins (Steno bredanensis) (Baird et al. 2008a). Limited satellite tagging work has been undertaken with several species of odontocetes off of Kaua‘i and Ni‘ihau, with deployments of tags on melon-headed whales (Peponocephala electra) in 2008 (Woodworth et al. 2011); short-finned pilot whales (Globicephala macrorhynchus) in 2008 and 2011 (Baird et al. 2008b, 2011), and bottlenose dolphins and rough-toothed dolphins in 2011 (Baird et al. 2012). The satellite tag deployments have provided unbiased and longer-term information on movements and habitat use of all these species, although sample sizes for all species remain small.

As part of an assessment of habitat use and movements of odontocetes being undertaken in the western half of the main Hawaiian Islands (see Baird et al. 2011, 2012), field operations
funded by Commander, U.S. Navy Pacific Fleet were undertaken off of Kaua‘i in January 2012. There were two primary goals of these operations: 1) providing species verification for acoustic detections by the Marine Mammal Monitoring on Navy Ranges (M3R) project on the Pacific Missile Range Facility (PMRF) hydrophone range (see Moretti et al. 2012); and 2) deploying satellite tags prior to a Submarine Commanders Course (SCC) training event to be undertaken off Kaua‘i in February 2012. Such tag deployments would provide movement data before, during, and after the SCC, to allow for an assessment of changes in movement patterns/habitat use associated with the event, as well as providing baseline data on movements and habitat use that may be relevant to understanding stock structure and use of the Navy’s PMRF range. Secondary goals included obtaining identification photos of individuals to assess site fidelity and movements, and biopsy samples to contribute to genetic studies of stock structure. This report summarizes methods and results from small-boat based field efforts, satellite tagging, and photoidentification matching of tagged individuals during this project, including information on habitat use and movements. Assessment of potential changes in movement patterns/habitat use associated with the SCC will be undertaken separately.

Citation:

Baird, R.W., D.L. Webster, J.M. Aschettino, D. Verbeck, and S.D. Mahaffy. 2012. Odontocete Movements off the Island of Kaua‘i: Results of Satellite Tagging and Photo-Identification Efforts in January 2012. Prepared for U.S. Pacific Fleet, submitted to NAVFAC PAC by HDR Environmental, Operations and Construction, Inc.