gov.noaa.nodc:0244405 eng utf8 dataset NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NOAA Contact Information Information for contacts at NCEI. information custodian 2026-06-01T18:12:19Z ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) Reef fish Stationary Point Count (SPC) survey data collected by the Guam Long-term Coral Reef Monitoring Program from 2010-08-04 to 2024-11-19 (NCEI Accession 0244405) 2022-01-07 publication 2025-05-20 revision 2021-12-20 creation NOAA National Centers for Environmental Information gov.noaa.nodc:0244405 NCEI Archive Management System 0244405 NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information publisher David R. Burdick University of Guam burdickd@triton.uog.edu resourceProvider University of Guam resourceProvider David R. Burdick University of Guam burdickd@triton.uog.edu principalInvestigator The Guam Coastal Management Program collaborator Guam Bureau of Statistics and Plans collaborator University of Guam Marine Laboratory collaborator Burdick, David R. University of Guam Marine Laboratory burdickd@triton.uog.edu author Brown, Valerie NOAA Pacific Islands Regional Office https://www.fisheries.noaa.gov/about/pacific-islands-regional-office HTTPS Pacific Islands Regional Office (PIRO) website Institution web page information author Hershberger, Andrea University of Guam Marine Laboratory author Drake, Diona University of Guam Marine Laboratory author Schroeder, Robert NOAA Pacific Islands Regional Office https://www.fisheries.noaa.gov/about/pacific-islands-regional-office HTTPS Pacific Islands Regional Office (PIRO) website Institution web page information author University of Guam contributor tableDigital The data in this package include fish abundance, length, biomass, and presence/absence data collected at High Priority Reef Areas (HPRA) by Guam Long-term Coral Reef Monitoring Program (GLTMP) biologists. The monitoring team uses a Stationary Point Count Method, adapted from Ault et al. (2006) and NOAA Fisheries, Coral Reef Ecosystem Division (Williams et al., 2011), to conduct the reef fish surveys. 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 sites 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 the HPRAs were selected based on management priority, the site boundaries were delineated using bathymetry and benthic habitat data within ArcGIS and the locations of the sampling stations were generated randomly within each site’s boundaries using ArcGIS. The reef fish SPC surveys, as well as benthic photo transect, macroinvertebrate belt transect, coral quadrat (through 2019), and rugosity surveys were 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 were 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. IMPORTANT NOTE: Changes have been made to the fish SPC survey methodology since its first deployment in 2010. These changes, which are documented in detail in the Data Quality and Lineage sections of the NOAA InPort metadata record, must be considered in order to properly analyze these data. Also, please note that the results of a 2020 analysis of the fish SPC data conducted by Dr. Peter Houk of the University of Guam Marine Laboratory, and a 2023 analysis carried out by the GLTMP coordinator, found significant interobserver biases that must be taken into account during any analysis of these data. Dr. Houk's analysis also suggested that data collected in 2010 and 2011 by a relatively inexperienced observer did not meet quality assurance standards. Observations recorded by this observer were not included in the dataset submitted to NCEI; however, these data can be made available upon request. More information regarding the accuracy, bias, and comparability of these data can be found in the InPort metadata record. The goals of the Guam Long-term Coral Reef Monitoring Program (GLTMP) are to determine the status and trends of selected coral reef ecosystem indicators to inform resource managers' decision-making process, provide managers with early notice of abnormal conditions, provide data to better understand the dynamic nature of the island's coastal ecosystems, allow resource agencies to meet certain legal and Congressional mandates, and measure progress towards performance goals. Reef fish survey data collected by the GLTMP at several High Priority Reef Areas around Guam provide documentation of the status and trends of the reef reef fish communities at these sites. Funding Agency: NOAA Coral Reef Conservation Program completed historicalArchive NOAA National Centers for Environmental Information ncei.info@noaa.gov https://www.ncei.noaa.gov/contact HTTPS NCEI Contact Information Information for contacts at NCEI. information pointOfContact asNeeded NCEI Accession 0244405 was revised and a new version of the archival package was published. Updates to existing archival packages may provide additional files or replace obsolete files. The latest version contains the most complete and up-to-date representation of this archival information package. All of the files received prior to this update are available in the preceding version of this accession. Please see journal.txt in the /about directory for additional details on changes made. https://www.ncei.noaa.gov/access/metadata/landing-page/bin/gfx?id=gov.noaa.nodc:0244405 Preview graphic PNG 0244405 NCEI ACCESSION NUMBER 2025-04-28 publication FISH - CORAL REEF FISH BIOMASS FISH CENSUS FISH SPECIES INDIVIDUAL FISH EXAMINATION - LENGTH SPECIES IDENTIFICATION SPECIES IDENTIFICATION - COUNT SPECIES IDENTIFICATION - ORGANISM LENGTH theme NODC DATA TYPES THESAURUS visual observation instrument NODC INSTRUMENT TYPES THESAURUS biological in situ survey survey - biological survey - coral reef visual observation theme NODC OBSERVATION TYPES THESAURUS University of Guam dataCentre NODC COLLECTING INSTITUTION NAMES THESAURUS University of Guam dataCentre NODC SUBMITTING INSTITUTION NAMES THESAURUS Coral Reef Conservation Program (CRCP) CORAL REEF STUDIES project NODC PROJECT NAMES THESAURUS Philippine Sea place NODC SEA AREA NAMES THESAURUS oceanography theme WMO_CategoryCode 2012-09-15 publication Guam Bureau of Statistics and Plans The Guam Coastal Management Program University of Guam Marine Laboratory dataCentre Contributing Organizations NA07NOS4260060 NA10NOS4260060 NA11NOS4820007 NA13NOS4820012 NA15NOS4820039 NA17NOS4820038 NA19NOS4820057 NA21NOS4820018 NA23NOS4820147 State and Territorial Government Cooperative Agreements project CRCP Project Comprehensive Long-term Coral Reef Monitoring at Permanent Sites on Guam project Provider Project Names Numeric Data Sets > Biology theme CoRIS Discovery Thesaurus EARTH SCIENCE > Biosphere > Ecological Dynamics > Species Richness EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Rapid Assessment Studies EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Reef Fish Census EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Reef Fish Census > Stationary EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral Reef Ecology EARTH SCIENCE > Oceans > Marine Biology > Fish EARTH SCIENCE > Oceans > Marine Biology > Fish > Fish Behavior EARTH SCIENCE > Oceans > Marine Biology > Fish > Fish Census theme CoRIS Theme Thesaurus EARTH SCIENCE > BIOLOGICAL CLASSIFICATION > ANIMALS/VERTEBRATES > FISH theme Global Change Master Directory (GCMD) Science Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian VISUAL OBSERVATIONS > VISUAL OBSERVATIONS instrument Global Change Master Directory (GCMD) Instrument Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian COUNTRY/TERRITORY > United States of America > Guam > Achang (13N144E0064) COUNTRY/TERRITORY > United States of America > Guam > Cocos Barrier Reefs (13N144E0001) COUNTRY/TERRITORY > United States of America > Guam > East Agana Bay (13N144E0063) COUNTRY/TERRITORY > United States of America > Guam > Fouha Bay (13N144E0024) COUNTRY/TERRITORY > United States of America > Guam > Guam (13N144E0000) COUNTRY/TERRITORY > United States of America > Guam > Piti Bay (13N144E0061) COUNTRY/TERRITORY > United States of America > Guam > Piti Bomb Hole (13N144E0052) COUNTRY/TERRITORY > United States of America > Guam > Tumon Bay (13N144E0004) COUNTRY/TERRITORY > United States of America > Guam > Western Shoal (13N144E0062) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Guam > Achang (13N144E0064) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Guam > East Agana Bay (13N144E0063) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Guam > Fouha Bay (13N144E0024) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Guam > Guam (13N144E0000) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Guam > Piti Bay (13N144E0061) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Guam > Piti Bomb Hole (13N144E0052) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Guam > Tumon Bay (13N144E0004) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Guam > Western Shoal (13N144E0062) OCEAN BASIN > Pacific Ocean > Western Pacific Ocean > Guam Reefs > Cocos Barrier Reefs (13N144E0001) place CoRIS Place Thesaurus OCEAN > PACIFIC OCEAN > NORTH PACIFIC OCEAN place Global Change Master Directory (GCMD) Location Keywords 2026 revision 24 Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA) Greenbelt MD https://forum.earthdata.nasa.gov/app.php/tag/GCMD%2BKeywords HTTPS GCMD Keyword Forum Page Global Change Master Directory (GCMD). 2025. GCMD Keywords, Version 21. Greenbelt, MD: Earth Science Data and Information System, Earth Science Projects Division, Goddard Space Flight Center (GSFC), National Aeronautics and Space Administration (NASA). URL (GCMD Keyword Forum Page): https://forum.earthdata.nasa.gov/app.php/tag/GCMD+Keywords information custodian 0DPD3W 5HAY7J UEL343 Send2NCEI Submission Package ID accessLevel: public otherRestrictions Cite as: Burdick, David R.; Brown, Valerie; Hershberger, Andrea; Drake, Diona; Schroeder, Robert (2022). Reef fish Stationary Point Count (SPC) survey data collected by the Guam Long-term Coral Reef Monitoring Program from 2010-08-04 to 2024-11-19 (NCEI Accession 0244405). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. https://www.ncei.noaa.gov/archive/accession/0244405. Accessed [date]. Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives. otherRestrictions Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose. license This dataset has been dedicated to the public domain under the Creative Commons CC0 1.0 Universal (CC0 1.0) Public Domain Dedication. SPDX License: Creative Commons Zero v1.0 Universal (CC0-1.0) University of Guam, 2025: Guam Long-term Coral Reef Monitoring Program Reef Fish Surveys since 2010, https://www.fisheries.noaa.gov/inport/item/47783. 2025 publication gov.noaa.nmfs.inport:47783 https://www.fisheries.noaa.gov/inport/item/47783 HTTPS https://www.fisheries.noaa.gov/inport/item/47783 InPort Metadata Record information NOAA Pacific Islands Fisheries Science Center (NMFS/PIFSC) publisher tableDigital crossReference Guam Coral Reef Initiative 2025 publication https://www.guamcoralreefs.info HTTPS https://www.guamcoralreefs.info Guam Coral Reef Initiative webpage information Guam Coral Reef Initiative author crossReference Guam Long-term Coral Reef Monitoring Program 2025 publication https://guamcoralreefmonitoring.wordpress.com/ HTTPS https://guamcoralreefmonitoring.wordpress.com/ Guam Long-term Coral Reef Monitoring Program webpage information Guam Long-term Coral Reef Monitoring Program author crossReference Burdick, David; Brown, Valerie; Miller, Roxanna; United States. National Ocean Service; Pacific Islands Region; University of Guam. Marine Laboratory. 2019. A report of the Comprehensive Long-term Coral Reef Monitoring at Permanent Sites on Guam project. https://repository.library.noaa.gov/view/noaa/29489 2019 publication noaa:29489 https://repository.library.noaa.gov/view/noaa/29489 HTTPS https://repository.library.noaa.gov/view/noaa/29489 Related report information United States. National Ocean Service author Pacific Islands Region author University of Guam. Marine Laboratory author Burdick, David author Brown, Valerie author Miller, Roxanna author documentDigital crossReference Burdick, D.R., Raymundo, L., Drake, D., and Hershberger, A. 2023. A decade of change on Guam’s coral reefs: A report of Guam Long-term Coral Reef Monitoring Program activities between 2010 and 2021. University of Guam Marine Laboratory Technical Report 170. 120 p. https://www.uog.edu/_resources/files/ml/technical_reports/UOGML_TechRep170_GLTMP_2023.pdf 2023-08 publication https://www.uog.edu/_resources/files/ml/technical_reports/UOGML_TechRep170_GLTMP_2023.pdf HTTPS https://www.uog.edu/_resources/files/ml/technical_reports/UOGML_TechRep170_GLTMP_2023.pdf Related report information Burdick, David R. University of Guam Marine Laboratory burdickd@triton.uog.edu author Raymundo, Laurie University of Guam Marine Laboratory collaborator Drake, Diona University of Guam Marine Laboratory collaborator Hershberger, Andrea University of Guam Marine Laboratory collaborator documentDigital University of Guam Marine Laboratory Technical Report 170 crossReference eng; USA utf8 environment oceans biota 144.653677 144.798279 13.236 13.51677795 2010-08-04 2024-11-19 In this accession, NCEI has archived multiple versions of these data. The latest (and best) version of these data has the largest version number. NOAA National Centers for Environmental Information +1-301-713-3277 ncei.info@noaa.gov pointOfContact In most cases, electronic downloads of the data are free. However, fees may apply for custom orders, data certifications, copies of analog materials, and data distribution on physical media. Contact NCEI for other distribution options and instructions. CSV Excel PDF 22.492 https://www.ncei.noaa.gov/archive/accession/0244405 HTTPS Web browser NCEI Dataset Landing Page Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/oas/244405 HTTPS Web browser Descriptive Information Navigate directly to the URL for a descriptive web page with download links. information https://www.ncei.noaa.gov/archive/accession/download/244405 HTTPS Web browser HTTPS Navigate directly to the URL for data access and direct download. download ftp://ftp-oceans.ncei.noaa.gov/nodc/archive/arc0193/0244405/ FTP Any FTP client FTP These data are available through the File Transfer Protocol (FTP). FTP is no longer supported by most internet browsers. You may copy and paste the FTP link to the data into an FTP client (e.g., FileZilla or WinSCP). download dataset NCEI Accession 0244405 v1.1 was published. 2022-01-07T14:19:27Z NCEI Accession 0244405 v1.1 publication https://www.ncei.noaa.gov/archive/accession/0244405/1.1 HTTPS NCEI Accession 0244405 v1.1 published 2022-01-07T14:19:27Z download NCEI Accession 0244405 was revised and v2.2 was published. Updates were received for this dataset. These updates were copied into the data/0-data/ directory of this accession. These updates may provide additional files or replace obsolete files. This version contains the most complete and up-to-date representation of this archival information package. All of the files received prior to this update are available in the preceding version of this accession. 2024-11-12T13:56:10Z NCEI Accession 0244405 v2.2 publication https://www.ncei.noaa.gov/archive/accession/0244405/2.2 HTTPS NCEI Accession 0244405 v2.2 published 2024-11-12T13:56:10Z download NCEI Accession 0244405 was revised and v3.3 was published. Updates were received for this dataset. These updates were copied into the data/0-data/ directory of this accession. These updates may provide additional files or replace obsolete files. This version contains the most complete and up-to-date representation of this archival information package. All of the files received prior to this update are available in the preceding version of this accession. 2025-05-20T19:41:57Z NCEI Accession 0244405 v3.3 publication https://www.ncei.noaa.gov/archive/accession/0244405/3.3 HTTPS NCEI Accession 0244405 v3.3 published 2025-05-20T19:41:57Z download dataset Parameter or Variable: FISH CENSUS (measured); Units: cm; Observation Category: in situ; Sampling Instrument: visual observation; Sampling and Analyzing Method: The GLTMP fish team used a Stationary Point Count Method (SPC) adapted from Ault et al. (2006) and NOAA Fisheries Coral Reef Ecosystem Division (Williams et al., 2011). Slight modifications to the method were made in 2012, allowing more refined classification of non-instantaneous observations, but more substantial changes to the method were implemented beginning in 2020. These changes are detailed in Process Step 4 of the NOAA InPort metadata record for this dataset. While the core method remained intact, and some parameters are still directly comparable across all years, these changes must be taken into account when making comparisons of certain parameters using observational data obtained before 2020 and those obtained during and after 2020. All sampling stations within a given monitoring site were initially selected from hard-bottom habitats using a stratified random sampling design; a combination of fixed and non-fixed transects were utilized within each monitoring site (split-panel approach). Each sampling station was located using a GPS receiver. A 30-meter transect was laid in a clockwise direction relative to the island, following the depth contour if it could be readily determined or parallel to the reef margin for flat areas. To conduct the reef fish surveys divers were positioned at 7.5 m and 22.5 m along the transect and counted fish within a 7.5 m radius cylinder extending from the substrate to the limits of vertical visibility. The simultaneous surveys started once the divers deployed the transect and both divers were ready to proceed. A fish diver partnered with a trainee or a benthic diver when two fish divers were not available. In this situation, the fish diver laid the transect and conducted the first SPC at 22.5 m while the other diver remained along the 0-15 m section; the divers then switched positions along the transect and conducted their respective surveys. The SPC surveys were conducted in two parts. During the first five minutes, divers recorded all species observed within the cylinder, but did not count or size fish. All fish were identified to species level or the next lowest taxonomic level possible (genus or family). While some small and/or cryptic taxa, such as most gobies or blennies, were not given high priority and were usually not reported, some larger-bodied or otherwise notable representatives of those taxa, such as Exalias brevis, Plagiotremus spp., and Valenciennea strigata were typically reported. Small fishes and those cryptic during the day, such as apogonids and holocentrids, were targeted for the survey but were likely undercounted. If a rare fish (shark, species of concern, large mobile predators, etc.) was observed during the first 5 minutes, it was counted and sized, but the diver noted that it was not an instantaneous count. Note that this approach to surveying rare fish was not in place during surveys carried out at the Tumon Bay and East Agana Bay in 2010 and at the Western Shoals site in 2011. For surveys at these sites during that time period rare fish were counted and sized but it was not clear if it was an instantaneous count or not. After the first five minutes divers enumerated fish, one species grouping at a time, using rapid visual sweeps of the plot. The counts were designed to be instantaneous to avoid double counting. All fish of the target species within the SPC boundaries were counted and sized to the nearest centimeter; however, divers used size classes for large schools or high densities. At the end of the survey, divers swam throughout the 7.5-m radius plot to enumerate small and cryptic species that were not captured from the stationary central position. Note that the list of species targeted for counting and sizing changed beginning in 2020 to include only food fishes, while some non-food fishes (e.g., butterflyfishes and angelfishes) were still counted but not sized. The status of each species as a food fish or non-food fish is indicated in the dataset, as is the observation type (e.g., count and size, count only, presence/absence only) implemented beginning in 2020. Raw data include individual fish observation records with the corresponding methodological information and physical data that reflect the description of the site. Fish observation records include species identification, counts, total length (cm), length-weight values, biomass values, and trophic group designation. The physical/methodological data for all records includes the following: site, station, station type (fixed or unfixed), observer, date (day, month, year), latitude (dd), longitude (dd), transect, cylinder radius (m), SPC replicate, observation type (instantaneous/non-instantaneous/presence), depth (m), stratum, and wave exposure. Observations queried from Microsoft SQL server were reformatted to maintain consistency with previous NCEI submissions. This data set does not contain zero counts for species not observed at a given sampling station, but zero counts should be accounted for when calculating mean values for parameters across sampling stations (e.g., by using the expand_grid function in R).; Data Quality Method: Observations included in this dataset were made by divers who were trained and met minimum standards in fish species identification, fish counts, and total length estimates. All observations entered into the database through the online data entry system were compared against observations recorded on the raw data sheets. Once all database records were verified the quality control process was marked as complete for all observations associated with a given station/sampling period. This data entry and quality control process was conducted by the fish team lead. It should also be noted that the data management system employs hard and soft validation to minimize data entry errors. Observations, including species identification, counts, and cylinder size and fish length estimates were periodically checked for consistency between divers. However, it wasn't until an analysis of 2010-2019 data carried out in 2020 by Dr. Peter Houk of the University of Guam Marine Laboratory that significant interobserver biases were detected. These biases, which are described in detail in the Bias and Comparability sections of the NOAA InPort metadata record for this dataset, appear to be related to the detection of more cryptic taxa, such as holocentrids and the detection of a greater number of larger-sized fish by a more experienced observer. No significant differences in the accuracy of species identifications or size estimates were detected between the two observers whose data comprises nearly all of the observations included in this dataset. Observations by another observer was removed from the dataset following Dr. Houk's study, as it was determined that total biomass and individual size estimates for survey replicates conducted by a relatively inexperienced observer in 2010 and 2011 were consistently higher in comparison to survey replicates carried out by a more experienced observer. Data collected by this observer can be made available upon request. A 2023 analysis of fish observations collected between 2010 and 2022 (see Burdick et al., 2023) found that the interobserver biases discussed above resulted in significant discrepancies in mean biomass, density, and diversity values calculated at the site level. In general, biomass, density, and diversity values calculated using observations obtained by the more experienced fish observer (Observer 1) were greater than values calculated using observations obtained by Observer 2. Any comparison of data collected during the same time period by these two observers must account for these biases, as does any comparison of data collected before 2020 (by both Observer 1 and Observer 2) to data collected during and after 2020 (solely by Observer 2). While a newer observer (Observer 5) underwent a lengthy training and calibration period a formal investigation of interobserver bias using data obtained by this observer has not yet been conducted. It is recommended that any analysis of these data be preceded by an investigation of interobserver biases that may be present between observers 2 and 5. Small fishes and those cryptic during the day, such as apogonids and holocentrids, were likely undercounted. While some small and/or cryptic taxa, such as most gobies or blennies, were not given high priority in the survey and were usually not reported, some larger-bodied or otherwise notable representatives of those taxa, such as Exalias brevis, Plagiotremus spp., and Valenciennea strigata may have been reported. It should also be noted that the SPC method employed by the GLTMP is likely biased against larger-bodied species that are harvested and which tend to avoid divers. Larger bodied, harvested fish species such as Lethrinus xanthocheilus, Monotaxis grandoculis, and Macolor spp. were sometimes observed beyond the survey cylinder boundaries, as these species generally maintained at least an 8-10 m distance from divers using open-circuit scuba equipment. It is highly recommended that the GTLMP reef fish SPC survey data be used in combination with data collected using other methods to more accurately assess the status of these and other taxa that are less likely to be detected using this SPC method. asNeeded Metadata are developed, maintained and distributed by NCEI. Updates are performed as needed to maintain currentness. NOAA National Centers for Environmental Information custodian visual observation visual observation not an instrument - maybe an observation type