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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)

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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.
  • 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].
gov.noaa.nodc:0244405
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Distributor NOAA National Centers for Environmental Information
+1-301-713-3277
ncei.info@noaa.gov
Dataset Point of Contact NOAA National Centers for Environmental Information
ncei.info@noaa.gov
Time Period 2010-08-04 to 2024-11-19
Spatial Bounding Box Coordinates
West: 144.653677
East: 144.798279
South: 13.236
North: 13.51677795
Spatial Coverage Map
General Documentation
Associated Resources
  • University of Guam, 2025: Guam Long-term Coral Reef Monitoring Program Reef Fish Surveys since 2010, https://www.fisheries.noaa.gov/inport/item/47783.
  • Guam Coral Reef Initiative
  • Guam Long-term Coral Reef Monitoring Program
  • Burdick, D.R., Brown, V., and Miller, R. 2019. A report of the Comprehensive Long-term Coral Reef Monitoring at Permanent Sites on Guam project: Including the results of an analysis of coral reef monitoring data collected at high priority reef areas between 2010 and 2018. Non-series Report. 138 p. https://repository.library.noaa.gov/view/noaa/29489
  • 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
Publication Dates
  • publication: 2022-01-07
  • revision: 2025-05-20
  • creation: 2021-12-20
Data Presentation Form Digital table - digital representation of facts or figures systematically displayed, especially in columns
Dataset Progress Status Complete - production of the data has been completed
Historical archive - data has been stored in an offline storage facility
Data Update Frequency As needed - 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.
Supplemental Information
In this accession, NCEI has archived multiple versions of these data. The latest (and best) version of these data has the largest version number.
Purpose 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.
Use Limitations
  • accessLevel: Public
  • 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.
Dataset Citation
  • 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].
Cited Authors
Principal Investigators
Collaborators
  • The Guam Coastal Management Program
  • Guam Bureau of Statistics and Plans
  • University of Guam Marine Laboratory
Contributors
Resource Providers
Publishers
Acknowledgments
  • Funding Agency: NOAA Coral Reef Conservation Program
Theme keywords NODC DATA TYPES THESAURUS NODC OBSERVATION TYPES THESAURUS WMO_CategoryCode
  • oceanography
CoRIS Discovery Thesaurus
  • Numeric Data Sets > Biology
CoRIS Theme 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
Global Change Master Directory (GCMD) Science Keywords
Data Center keywords NODC COLLECTING INSTITUTION NAMES THESAURUS NODC SUBMITTING INSTITUTION NAMES THESAURUS Contributing Organizations
  • Guam Bureau of Statistics and Plans
  • The Guam Coastal Management Program
  • University of Guam Marine Laboratory
Instrument keywords NODC INSTRUMENT TYPES THESAURUS Global Change Master Directory (GCMD) Instrument Keywords
Place keywords NODC SEA AREA NAMES THESAURUS CoRIS Place Thesaurus
  • 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)
Global Change Master Directory (GCMD) Location Keywords
Project keywords NODC PROJECT NAMES THESAURUS CRCP Project
  • NA07NOS4260060
  • NA10NOS4260060
  • NA11NOS4820007
  • NA13NOS4820012
  • NA15NOS4820039
  • NA17NOS4820038
  • NA19NOS4820057
  • NA21NOS4820018
  • NA23NOS4820147
  • State and Territorial Government Cooperative Agreements
Provider Project Names
  • Comprehensive Long-term Coral Reef Monitoring at Permanent Sites on Guam
Keywords NCEI ACCESSION NUMBER
Keywords Send2NCEI Submission Package ID
  • 0DPD3W
  • 5HAY7J
  • UEL343
Use Constraints
  • 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].
Data License
Access Constraints
  • 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.
Fees
  • 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.
Lineage information for: dataset
Processing Steps
  • 2022-01-07T14:19:27Z - NCEI Accession 0244405 v1.1 was published.
  • 2024-11-12T13:56:10Z - NCEI Accession 0244405 was revised and v2.2 was published.
    Rationale: 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 was revised and v3.3 was published.
    Rationale: 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.
Output Datasets
Lineage information for: dataset
Processing Steps
  • 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.
Acquisition Information (collection)
Instrument
  • visual observation
Last Modified: 2025-12-14T19:30:48Z
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