Macroinvertebrate belt transect survey data collected by the Guam Long-term Coral Reef Monitoring Program from 2010-08-06 to 2024-11-19 (NCEI Accession 0228762)

The data in this package include macroinvertebrate belt transect survey data collected collected at High Priority Reef Areas (HPRAs) by the Guam Long-term Coral Reef Monitoring Program (GLTMP) between 2010 and 2024. GLTMP biologists counted the number of individuals of commercially and ecologically important macroinvertebrate species within a 4 m x 30 m belt transect (4 x 25 m prior to 2017) at all sampling stations within the HPRAs (except at the Western Shoals stations, where 4 m x 15 m belts were used). The longest dimension of Tridacna individuals was also recorded; these measurements are not included in this dataset but can be provided upon request. Boring urchins, small sea stars, and other small or cryptic taxa were excluded from the survey beginning in 2020. Observations queried from a Microsoft SQL server database were reformatted using a custom R script prior to submission to NCEI. The reformatted data set includes zero counts for all taxa not detected during the survey at each sampling station. These data were collected using a split-panel sampling approach, whereby a mix of permanent and non-permanent sampling stations (one sampling station = one transect) were visited within each HPRA. The HPRAs were selected by an advisory body comprised of reef managers, researchers, and technicians. The HPRAs were not selected randomly from around the island and thus should not be considered representative of reef condition at the island-scale. While the general location of each HPRA was selected based on management priority, the site boundaries were delineated using bathymetry and benthic habitat data within ArcGIS; the locations of the sampling stations were generated randomly within each site’s boundaries using ArcGIS. The macroinvertebrate belt transect surveys, as well as benthic photo transect, reef fish SPC, and rugosity surveys are carried out on an annual basis along the seaward slope between 7 and 15 m depth in the Tumon Bay Marine Preserve and in East Agana Bay, while surveys are carried out biennially within the Piti Bomb Holes Marine Preserve, the Achang Reef Flat Marine Preserve, the eastern side of the Cocos Barrier Reef (Cocos-East), and Fouha Bay. Surveys were also carried at along reef margin (1-2 m) and slope (2-15 m) of Western Shoals, in Apra Harbor, in 2011. The GLTMP has conducted surveys at the Tumon and East Agana HPRAs since 2010 and the Piti HPRA since 2012. Data collection for the Achang and Cocos-East HPRAs began in 2014 and at the Fouha Bay HPRA in 2015. Baseline data is available for the Western Shoals HPRA from 2011 but this site has not been re-visited since its establishment due to shifting management priorities.