An Assessment of the Impact of Derelict Fishing Nets on the Coral Reef Habitats of Midway Atoll
The Northwestern Hawaiian Islands (NWHI) Papahanaumokuakea Marine National Monument (PMNM) has the highest level of protection that a marine environment can receive. However, the reefs are still vulnerable to anthropogenic impacts originating outside the Monument boundaries and beyond the control of local managers, including marine debris. Entanglement of megafauna such as threatened green sea turtles and endangered Hawaiian monk seals are conspicuous manifestations of the marine debris problem. However, very little is known about the impacts of these nets to benthic NWHI reef communities. Derelict nets damage shallow coral reefs in multiple ways. Nets may snag and dislodge corals as they are pushed across reefs by swells, surge, and currents. The nets may also settle on living reef, smothering the organisms beneath them. Nets may facilitate introductions of invasive species by allowing them to raft into new areas from distant reefs. Finally, removal of the nets may cause further disturbance to the benthos, including damage to organisms that have settled on the nets. We propose to investigate the impacts from nets that become entangled on the reefs by tracking the changes in the benthic community over time, that occur either after their removal, or when they are left in place.
- NOAA Papahanaumokuakea Marine National Monument
- NOAA PIFSC, Coral Reef Ecosystem Division
- Midway Atoll National Wildlife Refuge
This will be the first study that looks directly at the impacts that derelict fishing nets have on the benthic communities of the reefs of the Hawaiian Islands.
Results may influence the determination of whether all nets that are on the reefs should be removed.
Information will be provided to managers that quantifies the damage occurring to the benthic communities.
Data will provide the beginnings of a timeline for the potential recovery of areas damaged by derelict fishing nets.
Map of Papahanaumokuakea Marine National Monumnet with photo of Midway. Photo courtesy of K. Keller, PMNM.
Diver removes net from the reef. Photo courtesy of NOAA Fisheries.
Derelict Fishing Net on Coral in the NWHI. Photo courtesy of NOAA Fisheries.
Download the 1-pager handout (pdf 257KB) on this project here.
This project is funded through NOAA's Ocean Service, Office of Response & Restoration, Marine Debris Program.