NOAA Pacific Islands Fisheries Science Center, Ecosystem Science Division Coral Reef Ecosystem Program, Rapid Ecological Assessments of Fish Belt Transect Surveys (BLT) at Coral Reef Sites across the Pacific Ocean from 2000 to 2009

Sampling event
Latest version published by United States Geological Survey on Jan 27, 2023 United States Geological Survey

Download the latest version of this resource data as a Darwin Core Archive (DwC-A) or the resource metadata as EML or RTF:

Data as a DwC-A file download 26,447 records in English (19 MB) - Update frequency: not planned
Metadata as an EML file download in English (7 KB)
Metadata as an RTF file download in English (7 KB)


Belt transects (BLT) are a non-invasive underwater-survey method that enumerates the diverse components of diurnally active shallow-water reef fish assemblages. At each Rapid Ecological Assessment survey site, BLT fish surveys are conducted along 3 consecutively-placed, 25m transect lines to quantify relatively small-bodied and abundant fishes. A pair of scuba diver-observers conducts parallel swims along the transect lines, recording size-class specific counts of all fishes encountered, to species-level where possible, within visually estimated but defined belt widths: 4 m wide for fishes > 20 cm TL (100 m2 area) on the initial swim-out, and 2 m wide for fishes < 20 cm TL (50 m2 area) on the subsequent swim back. Transect lines are typically set at depths of 10-15 m. Reef ledges and holes are visually searched. Stations are completed on all sides of the island/atoll, weather and sea conditions permitting. Raw survey data includes species level abundance estimates.

Data Records

The data in this sampling event resource has been published as a Darwin Core Archive (DwC-A), which is a standardized format for sharing biodiversity data as a set of one or more data tables. The core data table contains 26,447 records.

2 extension data tables also exist. An extension record supplies extra information about a core record. The number of records in each extension data table is illustrated below.

Event (core)

This IPT archives the data and thus serves as the data repository. The data and resource metadata are available for download in the downloads section. The versions table lists other versions of the resource that have been made publicly available and allows tracking changes made to the resource over time.


The table below shows only published versions of the resource that are publicly accessible.

How to cite

Researchers should cite this work as follows:

Coral Reef Ecosystem Program; Pacific Islands Fisheries Science Center (2017). Pacific Reef Assessment and Monitoring Program: Rapid Ecological Assessments of Fish Belt Transect Surveys (BLT) in the Pacific Ocean from 2000-09-09 to 2009-05-05 (NCEI Accession 0162462). NOAA National Centers for Environmental Information. Dataset.


Researchers should respect the following rights statement:

The publisher and rights holder of this work is United States Geological Survey. To the extent possible under law, the publisher has waived all rights to these data and has dedicated them to the Public Domain (CC0 1.0). Users may copy, modify, distribute and use the work, including for commercial purposes, without restriction.

GBIF Registration

This resource has been registered with GBIF, and assigned the following GBIF UUID: 89a2cd92-b5e0-44da-862b-968e12e1036f.  United States Geological Survey publishes this resource, and is itself registered in GBIF as a data publisher endorsed by U.S. Geological Survey.


Samplingevent; Samplingevent


Ivor Williams
  • Originator
Research Fish Biologist
National Oceanic and Atmospheric Administration
Annette DesRochers
  • Metadata Provider
Data Steward
National Oceanic and Atmospheric Administration
Tye Kindinger
  • Point Of Contact
Supervisory Coral Reef Ecosystems Researcher
National Oceanic and Atmospheric Administration
Jake Asher
  • Point Of Contact
Marine Ecosystems Research Specialist
National Oceanic and Atmospheric Administration
Abby Benson
  • Publisher
U.S. Geological Survey
Sarah Bingo
  • Processor
Data Manager
Pacific Islands Ocean Observing System

Additional Metadata

marine, harvested by OBIS These data were named with "NCRMP" in the OBIS shortname, when it is actually pre-NCRMP data. The creators of the data, PIFSC, wanted to make that correction, but after the data are submitted the shortname cannot change. The BLT transects were conducted under CRED using older methods before NCRMP was fully formed.

Alternative Identifiers 89a2cd92-b5e0-44da-862b-968e12e1036f