HAWAIIAN SPINNER DOLPHIN ABUNDANCE, DISTRIBUTION AND DEMOGRAPHICS
Background Information
Spinner dolphins (Stenella longirostris) are one of Hawaiʻi’s most familiar dolphin species. Their occurrence is well known throughout the islands and in many places, they can be seen from shore resting in shallow, sandy bays. Despite their close proximity, little is known about the overall population size, distribution or age structure of these animals.
Hawaiian spinner dolphins have important ecological, cultural and economic value (Wiener et al., 2020) for the community. They also have some of the highest levels of exposure to human activities of any marine mammal population anywhere in the world (Tyne et al., 2018). As such, monitoring their health and conservation status is vital. An understanding of how many animals there are, their habitat preferences, and the age structure of the population is key information for successful conservation monitoring.
AIMS
Researchers at MMRP are leading three projects to learn more about the population biology of Hawaiʻi’s spinner dolphins.
Project 1 will provide abundance estimates and distribution models for spinner dolphins around all of the main Hawaiian Islands.
Specific aims:
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Produce abundance estimates for the Oʻahu / 4-islands and Hawaiʻi Island spinner dolphin stocks
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Investigate the distribution and habitat preferences of spinner dolphins throughout the study region using spatial models
Project 2 is focused on the dolphins of the Kona coast of Hawaiʻi Island, and is looking in detail at the age strutcure of this population.
Specific aims:
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Develop a new method to estimate the age of animals using drone photogrammetry (which will be used in project 3).
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Estimate age structure (or group composition - proportion of calves / juveniles and adults within a group).
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Assess the age structure of the overall Kona population.
Project 3 is focused on the dolphins of the Waiʻanae coast of Oʻahu, collecting detailed information on this specific population of animals, including population size and age structure estimates.
Specific aims:
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Create a photo-identification catalogue of distinctly marked individuals from the Waiʻanae coast of Oʻahu
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Estimate the size and age-structure of the Waiʻanae coast population.
research team
Claire Lacey – MMRP (Project 1)
Fabien Vivier - MMRP (Project 2)
Liah McPherson – MMRP (Project 3)
Lars Bejder – MMRP
We would also like to acknowledge and thank all of our close collaborators at NOAA / PIFSC
For fieldwork updates, like and follow our project Facebook page.
For questions, concerns, or more information about the project, contact the research team at mmrp.naia@gmail.com. We also invite you to download our double-sided trifold brochure by clicking the image below. Please feel free to print, fold, and distribute.
Mahalo to our partners and supporters
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