According to researchers, spinner dolphins rest during the day so they have energy to effectively hunt at night. Human interactions can disrupt resting dolphins, impact mothers tending to their young, or interrupt mating behavior, all of which could lead to a reduction in the size of the population.

To gain a better understanding of how wildlife and humans use protected bays, underwater recording devices were deployed on Maui and Lanai to record sounds from marine mammals and boats.

The devices were deployed by a coalition of conservation groups in partnership with government agencies to learn how to better protect marine life at Honolua-Mokule’ia and Manele-Hulopo’e Marine Life Conservation Districts (MLCDs).

“These areas harbor some of the most exceptional marine life in Hawaii, including dolphins, manta rays, turtles and coral reefs teeming with life,” said Emily Fielding, Maui Marine Program director for TNC.

“Because there were so few tourists when the Ecological Acoustic Recorders, or EARs, were initially deployed, we will have a unique opportunity to observe if and how the behavior of spinner dolphins and other marine animals changes as visitors return to these areas once the data is retrieved and analyzed.”

The EARs will be collecting data over the next year and will provide a better understanding of when dolphins come into the MLCDs, how long they stay during daytime resting periods, if their presence is greater or lesser over time and how human activities like snorkeling and boating may change their behavior.

This information will help marine resource managers develop targeted management strategies to minimize pressures on dolphins and other marine life.

“We are seeking to better understand how spinner dolphins respond to human use in these MLCDs, so that we can ensure the dolphins are getting the time and space they need to survive and thrive in Maui’s waters,” said Russell Sparks, state Department of Land and Natural Resources’ Division of Aquatic Resources (DLNR-DAR) Maui biologist.

The project is a collaborative effort of The Nature Conservancy, Hawaiian Islands Humpback Whale National Marine Sanctuary, DLNR-DAR, Oceanwide Science Institute and the Hawaii Association for Marine Education and Research, Pulama Lanai.

Over the past decade, TNC has worked with DAR and local community partners to develop Conservation Action Plans (CAPs) for six existing marine conservation areas across Maui Nui to identify natural resources, threats and solutions to help guide effective ocean management.

CAP Teams for the Maui and Lanai MLCDs prioritized management of protected species and the provision of safe places for spinner dolphins to rest and play undisturbed.

“We are excited to partner with TNC and DAR to collect this valuable data using remote passive technology,” said Allen Tom, superintendent of the Hawaiian Islands Humpback Whale National Marine Sanctuary.

“This project has worldwide implications for marine protected area management, and it takes the effort of federal, state and local partners to move a project like this forward.”