NOAA's Marine Debris Blog

Keepin' the Sea Free of Debris!


Leave a comment

Derelict Fishing Nets and the Pacific Islands

Derelict fishing nets are a big marine debris problem. These nets can entangle wildlife, create major hazards to navigation, and can damage sensitive and important habitats. Unfortunately, they can also be difficult to address as they often have few identifying characteristics. This makes determining their source challenging and makes derelict nets difficult to track.

Derelict fishing nets are a particularly large problem in the Hawaiian archipelago, due to Hawaii’s geographic location in the North Pacific Gyre and Convergence Zone and the large amounts of fishing that occurs domestically and internationally in the Pacific. The North and East Coast shorelines of each Hawaiian Island are the most impacted, due to the northeast trade winds that blow this debris ashore. These nets may come from local origin or from far-off sources throughout the Pacific, but it’s difficult to tell without identifying markers such as a specific regional style (which can often be used to determine the general source of debris like derelict crab traps), serial numbers, or writing. Interestingly, Hawaii’s main commercial fishing industry is longline fishing targeting pelagic (open ocean) species, but the majority of the nets and ropes found in Hawaii are made of trawl or purse seine types, which suggests they are likely not of local origin.

No matter where these derelict nets hail from, they create a problem in this region that must be addressed. Prevention is the key to addressing marine debris, so raising awareness about the issue and educating fishermen is important. However, since the origin of most of these derelict nets is unknown and there are already many nets that litter Hawaiian shores, removal is also a very important part of solving the problem of derelict fishing nets. Recently, the NOAA Marine Debris Program (MDP) Pacific Islands Regional staff have received an increase in reports of huge derelict fishing net conglomerates, so removal efforts are particularly important.

There are currently many groups that are working to remove this debris, including the Hawai’i Wildlife Fund, which is leading net patrols and removing debris from over 200 miles of coastline on four different Hawaiian islands through a project recently funded by a MDP Community-based Marine Debris Removal Grant. Surfrider Kaua’i, previously funded by the MDP, is also active in conducting net patrols in Hawaii (check out the giant net they found!). In addition, there are numerous organizations performing beach cleanups in this area, including the State of Hawaii Department of Land and Natural Resources; these efforts have been an excellent example of the collaborative efforts put forth to implement the Hawai’i Marine Debris Action Plan. This removed debris is disposed of properly and when possible, and recycled through programs such as the Hawai’i Nets to Energy Program.

For more on derelict fishing nets in Hawaii, check out this 2014 interview with NOAA scientists.


Leave a comment

It’s a trap!

By: Courtney Arthur

Fishing traps, often used to catch crustaceans such as lobsters and crabs, may be abandoned, lost, or otherwise discarded in the marine environment. This type of derelict fishing gear is important to consider due to its widespread nature, persistence for long periods of time, and impacts that include “ghost fishing” and damage to sensitive marine habitats. Since these traps sit on the ocean floor, they are often forgotten about as a type of marine debris.

The NOAA Marine Debris Program took a regional approach in funding derelict trap research in locations across the country. We were interested to know how many traps were out there, if they were “ghost fishing,” and how the traps were impacting habitat and fisheries. Three scientists led studies in Virginia, the U.S. Virgin Islands, and the Florida Keys, and they will share their stories about derelict fishing gear and its impacts here on our blog in the coming weeks.

There’s also a significant amount of trap removal work going on across the country (e.g. North Carolina!), so we’ll also share success stories from partners. To kick us off, here’s some good news we recently heard from Timothy W. Jones, Aquatic Preserve Manager at St. Martins Marsh Aquatic Preserve in Florida:

This spring, the St. Martins Marsh Aquatic Preserve staff removed approximately 640 pounds of marine debris, including 60 derelict crab traps from the St. Martins Marsh Aquatic Preserve in a single day.

Once discarded or lost, a blue crab trap can remain in the environment for over a decade, continuing to trap marine life. Blue crabs, stone crabs, diamondback terrapins, and fish are among the marine life unintentionally captured. The staff discovered a deceased diamondback terrapin in one derelict crab trap, an unfortunate reality when dealing with derelict traps. Fortunately, they also found and returned a mangrove snapper and two blue crabs that were still alive. Once collected, the derelict traps are crushed down and brought back to land for disposal.

The Big Bend Seagrasses Aquatic Preserve, Florida’s largest aquatic preserve, which protects over 900,000 acres of submerged land, is supported by NOAA’s Coastal Zone Management Program and is home to mullet, sea trout, redfish, shrimp, oysters, scallops, manatee, osprey, dolphins, and sea turtles. Preventing derelict fishing gear from entangling and trapping these valuable species, and keeping their habitat free of degradation and damage is essential to their success.

Stay tuned for more!