Hawaii Coral Bleaching Collaborative: surveys for percent and severity of bleached coral cover across the Hawaiian Archipelago from 2019-08-20 to 2019-12-07 (NCEI Accession 0209239)

Coral bleaching surveys were conducted at both fixed and random sites using varying methods per institution that included: rapid visual assessments, photoquadrat assessments, and transect-intercept assessments. Metrics that were recorded include live coral cover, the percentage of living coral that was bleached, and the average severity of bleached corals. Surveys conducted in the Main Hawaiian Islands were conducted during shore-based missions, whereas surveys in the Northwestern Hawaiian Islands were performed opportunistically during the regularly scheduled NOAA National Coral Reef Monitoring Program (NCRMP) mission.

Random sites were selected by each institution in their own ways, as follows: - NOAA ESD: A stratified random sampling (StRS) design was used; the StRS method effectively reduces estimate variance through stratification using environmental covariates and by sampling more sites rather than sampling more transects at a site - DAR: Randomly chose sites by covering shorelines at depths from 1-15ft with hard bottom substrate, and aligned transects with shoreline access points - TNC: Sites were randomly selected using ARC-GIS within a polygon bounded by 15' and 50' depth clines and clipped to hard bottom habitat, based on NOAA habitat maps - HIMB: Hawaii Institute of Marine Biology's Coral Reef Ecology lab conducted coral bleaching surveys in Kaneohe Bay following methods outlined in the publications Bahr et al. 2015 and Bahr et al. 2017. - ASU: Sites were selected based on two factors: (1) bleaching reports sent into hawaiicoral.org (ASU, DAR, NOAA website) to locate potential hotspots on the Big Island; and (2) areas not reported as potential coldspots.

At each selected "site", randomly selected location GPS points constrained only by isobaths of 5, 10, and 15m - PACN: The National Park Service (NPS) National Park Service Pacific Island Inventory & Monitoring Network (PACN) conducted photoquadrat assessments of coral bleaching using the methods outlined in the PACN NPS Coral Bleaching Overview 2019, NPS_PACN_BenthicMonitoringSOP, and NPS_PACN_BenthicImageAnalysisSOP.