Olowalu manta ray and plankton community science project

HAMER proposes an Olowalu Prey-Field Index that unites manta research, plankton science, and hands-on community stewardship to track changes at the foundation of the reef food web. The index would track zooplankton abundance, biomass, and community composition alongside chlorophyll observations of phytoplankton and environmental conditions, with local seasonal baselines to help communities assess changes in the producer and consumer components of the plankton food web and identify conditions needing investigation. The project builds on 21 years of manta resighting records showcasing over 500 unique manta rays identified at Olowalu. A $10,000 Hawaiʻi Community Foundation Holomua Marine Initiative Pāpio grant already supports HAMER's partnership with Kīpuka Olowalu to engage residents in reef stewardship through plankton science, including standardized sampling, microscopy, data recording, and interpretation. Drone and boat surveys are underway and sampling equipment has been acquired; paired sampling before and after sunset, across manta aggregation areas and comparison sites, would test whether higher copepod concentrations help explain where mantas gather, with University of Hawaiʻi at Mānoa researchers and experienced plankton specialists providing scientific collaboration. DAR has agreed to standardize plankton sampling protocols with HAMER so community-collected observations can contribute to its Maui coastal monitoring. Public deliverables would include the tested index, mapped prey distributions, shared data, and plain-language reports to inform manta habitat protection, prioritize reef monitoring, guide water-quality and restoration discussions, and build a community monitoring network beyond the initial grant. Approximately $130,000 in Green Fee funding is sought toward the $150,000 research program to sustain sampling, laboratory analysis, index development, training, and management communication.