Structure from motion images collected during marine debris surveys at coral reef sites entangled with fishing nets at Pearl and Hermes Atoll in the Northwestern Hawaiian Islands from 2018/09/24 to 2018/10/03

September 24 to October 3, 2018 is the temporal coverage for this collection of Structure from Motion (SfM) photographs documenting derelict fishing nets on coral reefs. NOAA Fisheries scientists conducted in-water swim surveys at Pearl and Hermes Atoll in the Northwestern Hawaiian Islands, capturing standardized 3x3 meter plot images before and after net removal, along with paired control sites. The dataset provides a visual record for assessing the physical impact of marine debris on specific reef habitats.

Use Cases

• Quantifying changes in benthic substrate complexity before and after net removal using 3D models derived from the 'before' and 'after' image series.
• Comparing coral reef structure at net-impact sites to undisturbed 'control' sites photographed at least 50 meters away.
• Training machine learning models to identify derelict fishing nets or classify benthic cover within standardized 9-square-meter survey plots.
• Analyzing the spatial gradient of marine debris impact across the Pearl and Hermes lagoon, from high- to zero-debris locations.

Strengths

• Provides a controlled before-after-control-impact (BACI) design with paired image sets for each net site, enabling direct comparison.
• Surveys covered a defined spatial gradient across the lagoon, including locations where nets are common and where they have never been observed.
• Collection followed a standardized protocol: nets were selected based on specific interaction, depth (~1-4m), and size criteria, and all photos were taken within permanent 3x3m plots.

Limitations

• The dataset's exact size, row count, and specific column or image metadata are not provided across any platform.
• Data collection was limited to a specific 10-day mission in 2018 at a single atoll, restricting temporal and geographic scope.
• Conflicting 'last updated' dates exist between platforms (2018-10-03 vs. 2026-03 -05), casting uncertainty on metadata maintenance.

Provenance

Source

NOAA Fisheries, Ecosystem Sciences Division (ESD), National Oceanic and Atmospheric Administration, Department of Commerce

Collection Method

Collected during in-water marine debris swim surveys by snorkelers using a Structure from Motion (SfM) photographic approach within established 3x3 meter plots.

Time Range

2018-09-24 to 2018-10-03

Freshness

2026-03-05 22:41:37.686980

Geography

Pearl and Hermes Atoll, Northwestern Hawaiian Islands, Central Pacific Ocean