Skip to main content
U.S. flag

An official website of the United States government

This site is currently in beta, and your feedback is helping shape its ongoing development.

Benthic surveys along a water quality gradient in Aua, American Samoa: benthic images collected during belt transect surveys in 2022

Published by Pacific Islands Fisheries Science Center | National Oceanic and Atmospheric Administration, Department of Commerce | Metadata Last Checked: December 19, 2025 | Last Modified: 2022-10-01T00:00:00.000+00:00
This metadata record describes the imagery collected in 2022 of Aua Reef, American Samoa by the Ecosystem Sciences Division (ESD) of NOAA, funded by the Coral Reef Conservation Program (CRCP), to study effects of land-based source pollution by establishing biological, physical, and chemical baselines. In September 2022, NOAA scientists conducted benthic survey protocols at 18 study sites in Aua, American Samoa. The surveys implemented a one-stage stratified random sampling (StRS) design and the survey domain encompassed the majority of the mapped area of reef and hard bottom habitats in the 0 to 6 m depth range. Photoquadrat benthic images were collected along belt transect surveys of coral demography according to protocols established by NOAA National Coral Reef Monitoring Program (NCRMP) in 2015. Thirty images were collected along one, haphazardly laid, 30-m transects. Still photographs were collected to record the benthic community composition at predetermined points along belt transect with a high-resolution digital camera mounted on a pole. Photographs were taken every 1 m from the 1 m to the 30 m mark. This work generates 30 photographs per site, which are later analyzed by ESD staff and partners using the computer program CoralNet. This analysis is the basis for estimating benthic cover and composition at each site, which is documented and archived separately. The StRS design effectively reduces estimate variance through stratification using environmental covariates and by sampling more sites rather than more transects per site. Therefore, site-to-site comparisons should proceed with caution.

Find Related Datasets

Click any tag below to search for similar datasets

31303 Linking watershed management actions to reef health in American Samoa Visual Images > Habitats EARTH SCIENCE > Biosphere > Zoology > Corals EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > Baseline studies EARTH SCIENCE > Biosphere > Zoology > Corals > Reef Monitoring and Assessment > In Situ Biological EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral Reef Ecology EARTH SCIENCE > Oceans > Coastal Processes > Coral Reefs > Coral Reef Ecology > Benthic biology EARTH SCIENCE > Oceans > Marine Biology > Coral EARTH SCIENCE > Oceans > Marine Biology > Coral Communities PHOTOQUADRAT IMAGES camera imagery chartered vessel CORAL REEF STUDIES Coral Reef Conservation Program US DOC; NOAA; NMFS; Pacific Islands Fisheries Science Center; Ecosystem Sciences Division COUNTRY/TERRITORY > United States of America > American Samoa > Tutuila Island > Aua (14S170W0028) OCEAN BASIN > Pacific Ocean > Tutuila Island > Aua (14S170W0028) South Pacific Ocean Archipelagic Research Program CRCP ESD Ecosystem Sciences Division LBSP PIFSC Pacific Islands Fisheries Science Center land-based source pollution Aua DOC/NOAA/NMFS/PIFSC > Pacific Islands Fisheries Science Center, National Marine Fisheries Service, NOAA, U.S. Department of Commerce Benthic Missions

data.gov

An official website of the GSA's Technology Transformation Services

Looking for U.S. government information and services?
Visit USA.gov