USING TADPOLE-DEPLOYED SATELLITE TAGS TO STUDY DIEL MOVEMENTS OF SPINNER DOLPHINS IN HAWAIIAN WATERS

Sarasota Dolphin Research Program under NMFS/MMPA Scientific Research Permit No. 26622

Spinner dolphins in Hawaii spend the day in nearshore habitats where they are almost constantly exposed to human activities. Evidence of a decline in one population has raised concerns, and researchers have been working to estimate the abundance off each island to better examine trends. However, there is little information on the rate or extent of movements of individuals. Whether individuals remain strongly associated with smaller areas or move quickly and broadly around or between islands will influence the interpretation of abundance estimates, as well as the understanding of risks to the animals. We propose to study movement patterns by deploying satellite-linked tags on spinner dolphins using the TADpole deployment system. This system was recently successfully used with an Atlantic spotted dolphin in the Gulf of Mexico. We intend to tag up to eight free-swimming individuals with single-point Finmount satellite-linked tags. Results will provide the first detailed movement data for spinner dolphins in Hawaii over periods of weeks to months, and will help inform the design and interpretation of studies to examine abundance and trends. This project will also serve as a demonstration of the effectiveness of this tagging system, which should both reduce risks and increase tag attachment durations.