Derelict fishing nets wear down and break corals or even grow into the reef structure, smothering living coral. In this aerial photo, NOAA divers remove a large net from the reef at Pearl and Hermes Atoll. They painstakingly cut the nets off dense thickets of Porites compressa, also known as finger or hump coral, and pull it into deeper water to haul it away in the small boat. You can see the scar of bleached, dead reef in the upper right, where the net smothered the corals.
A juvenile Orangefin Dascyllus damselfish claims this large anemone as his home. This species is found only in the Line and Phoenix Islands. During the 70-day Pacific Reef Assessment Monitoring mission, teams of scuba divers conducted rapid ecological assessments of corals and reef fishes near American Samoa and the Pacific Remote Islands.
In addition to damaging corals, derelict fishing gear poses a serious choking and entanglement hazard to many threatened or endangered marine species and seabirds in the Northwestern Hawaiian Islands. This green sea turtle (called honu in Hawaiian) got tangled in a ball of fishing line and nets at Pearl and Hermes Atoll. Luckily, the team successfully untangled and released it shortly after this photo was taken.
A school of black jacks swim through a field of branching Acropora corals at Baker Island, where scientists were recording data. During the expedition, scientists measured physical and chemical characteristics of the coral reef environment such as water temperature, salinity, and carbonate chemistry. The teams also assessed impacts of ocean acidification on coral reef growth and removal.
The team works together to pull a large mass of nets into the boat near the barrier reef at Midway Atoll. There is no easy way to get nets from the water to the boat, and a successful net pull relies on creative use of knots, line, and muscle. This pile of tangled nets weighed 3,900 pounds.
Scientists work carefully to extract a core of skeleton from a coral head. This core acts as a record, allowing scientists back in the lab to learn more about the coral's history and possible ocean conditions over time.
Marine debris divers are towed underwater to look for derelict nets along a sand margin dropoff just inside the barrier reef of Pearl and Hermes Atoll. As nets are washed in over the barrier reef from the open ocean, small coral heads can be ripped off the substrate and become entangled in the net ball, causing the net to sink. Waves and currents push the nets across the sand and down the sand margin dropoff where the divers find them sitting at the bottom of the slope. The dark strip in this photo is piles of loose algae that have also accumulated at the bottom of the dropoff.
An arc-eye hawk fish perches on a Pocillopora coral. These predators lie in wait for unsuspecting small fishes and crustaceans to swim by, but if something bigger shows up, they are quick to dart into the safety of the coral branches.
Do you recognize any of these items? In addition to fishing nets, buoys, and floats, the team also finds everyday items that you might have in your home, including bottles, cigarette lighters, toys, toothbrushes, umbrella handles, and even shoes.
Ofu Island's backreef as a wave crests over the corals. After mass coral bleaching events across the Pacific Ocean in 2016 and 2017, scientists found major coral die-off in the Pacific Remote Islands. Scientists returned to the region to assess the health of coral reefs in 2018. The 2018 expedition marks the eight research voyage to American Samoa and tenth voyage to the Pacific Remote Islands Marine National Monument to assess coral reef conditions and recovery from mass bleaching.
Interactive "story maps" are available for each expedition. First, track NOAA's coral reef scientists as they travel through the Pacific, surveying coral reef ecosystems in some of the most remote and pristine locations on the planet. Then, follow NOAA scientists as they travel island to island, removing marine debris from the underwater and shorelines of the Papahānaumokuākea Marine National Monument.
Coral Survey Expedition Partners: Pacific Islands Fisheries Science Center, NOAA Coral Reef Conservation Program, National Marine Sanctuaries, American Samoa Department of Marine and Wildlife Resources, the NOAA Office of National Marine Sanctuaries in American Samoa, Hawaiʻi Institute of Marine Biology, San Diego State University, Scripps Institution of Oceanography, the U.S. Fish and Wildlife Service, and Woods Hole Oceanographic Institution.
Marine Debris Expedition Partners: Pacific Islands Fisheries Science Center, Pacific Islands Regional Office, NOAA Marine Debris Program, National Marine Sanctuaries, and the Damage Assessment Remediation and Restoration Program, the University of Hawaii's Joint Institute for Marine and Atmospheric Research, National Fish and Wildlife Foundation, U.S. Fish and Wildlife Service, Midway Atoll National Wildlife Refuge, the State of Hawaii’s Department of Land and Natural Resources, and the Papahānaumokuākea Marine National Monument.