Impacts of Human Activities on Spinner Dolphins (Stenella longirostris) in Their Resting Areas; Results from volunteer monitoring between March 2006 and October 2008, Final Report to the National Marine Fisheries Service Pacific Island Regional Office

Östman-Lind, Jan

Results of a community-based monitoring program initiated to document the effects of swim-with-wild-dolphin activities in critical spinner dolphin resting habitat on the Kona Coast. Study locations include Kaloko-Honokohau NHP marine waters and waters offshore of Puuhonua o Honaunau NHP. ABSTRACT: A substantial part of marine recreation in Hawaii focuses on viewing and swimming with spinner dolphins, a nocturnal species that rests near shore during the day, in protected bays and coves throughout the Island chain. This practice started on the Kona Coast, Island of Hawaii, some 20 years ago, where a substantial swim-with-dolphins industry and resident swim-with-dolphins community now has been established. There are also many resident marine conservationists, including many native Hawaiians, strongly opposed to these practices creating a very contentious environment. In an effort to collect information, as well as provide a constructive alternative for this conflict, a volunteer monitoring project was initiated in March 2006. Data were collected on standardized forms with an emphasis on measuring how the dolphins were affected by human proximity and behavior in the resting areas. Thirty-seven community volunteers collected a total of 566 hours of data from three bays, over 251 days, spanning 2.5 years. The dolphins spent most of their time in each bay within zone(s) designed to encompass the core resting area while people, mainly snorkelers and kayakers, primarily spent time in these zones when dolphins were present. When people were present in the core resting areas in Honaunau and Kealakekua Bays, the dolphins displayed more aerial behavior, especially those requiring high-energy including acrobatics and behavior associated with fast swimming. These patterns were evident throughout the day and appeared to discourage rest. An earthquake-generated landslide on the side of Kealakekua Bay resulted in the bay being closed off to human use for 18 days in the middle of the monitoring period, providing a natural experiment without humans near the core resting area. The dolphins responded by returning to behavior patterns close to those observed and described prior to the beginning of the swim-with-dolphin encounters. The data strongly support the establishment of human exclusion zones around traditional spinner dolphin resting areas, to enable the dolphins to get undisturbed rest.

Impacts of Human Activities on Spinner Dolphins (Stenella longirostris) in Their Resting Areas; Results from volunteer monitoring between March 2006 and October 2008, Final Report to the National Marine Fisheries Service Pacific Island Regional Office

Collections