Marine Debris
Flower Garden Banks

fishing line wrapped around a sponge on the sea floor
Discarded monofilament has been found entangled around sponges at Stetson Bank in Flower Garden Banks National Marine Sanctuary. Credit: Joyce & Frank Burek

Why is it a concern?

Marine debris is defined as any persistent, manufactured, or processed solid material that is directly or indirectly, intentionally or unintentionally, disposed of or abandoned into the marine environment. Marine debris includes a wide variety of objects (derelict fishing gear, lost vessel cargo, plastics, defunct research and monitoring equipment) that may pose a threat to the marine environment, human health and navigation.  Lost and discarded fishing gear, including longlines, monofilament lines, floats, nets, boat anchors, vessel stabilizers, discarded spear heads, and a spearguns, have been observed at East and West Flower Garden and Stetson Banks.

Potential threats to sanctuary resources due to marine debris include:

  • Smothering, entangling, and injuring animals and plants and creating an unstable habitat for those organisms that survive the initial impact.
  • Localized physical injury to coral reefs and rock outcrops.
  • Weakening of claystone substrate (Stetson Bank) and associated communities, leaving the substrate more vulnerable to erosion and fracturing by natural hazards, such as hurricanes.
  • Scouring and scraping caused by movement of waves and currents after settling
  • Habitat impacts resulting from the movement of dislodged debris.
  • Entrapment hazards to research activities.  Remotely operated vehicles, manned submersibles, and divers can potentially become entangled in fishing line, or nets, which can be difficult to see underwater.

Marine Debris has been removed by both technical and working scuba divers. A Tech Diving Research Cruise was completed in 2009 specifically targeting removal of marine debris.  During this expedition marine debris surveys and mapping were conducted and the identified debris was assessed for its impact on the biological communities of Stetson Bank and Bright Bank.  When feasible, debris items were removed by divers.

Overview of Research

The Flower Garden Banks National Marine Sanctuary is actively seeking research partners to conduct work connected to Marine Debris as a sentinel issue.

Project Name PI and contacts Links

Tech Diving Research Cruise

Flower Garden Banks NMS


Science Needs and Questions

  • What are the types and accumulation rates of probable marine debris within the sanctuary?
  • Are certain areas more or less susceptible to marine debris accumulation and/or impacts?
  • Are there critical habitat areas that should be prioritized for marine debris removal efforts?
  • What are the primary sources of marine debris in FGBNMS?

Education and Outreach Material

Marine Debris Assessment Expedition

NOAA Marine Debris Program Education Materials

NOAA’s Marine Debris Blog

Marine Debris Tracker App

Plastics, Plastics Everywhere! (194kb pdf)
- A look at how plastics affect the ocean environment and the impact that students and their families have on the amount of plastic bags used each day, week, and year.

discarded fishing net caught on coral
Lost and discarded fishing gear, such as this discarded shrimp net, are a form of marine debris and can cause entanglement and injury to marine animals and habitat. Credit: UNCW-UVP and FGBNMS, NOAA


Gittings, S.R., M. Tartt, and K. Broughton. 2013. National Marine Sanctuary System Condition Report 2013. U.S. Department of Commerce, National Oceanic and Atmospheric Administration, Office of National Marine Sanctuaries, Silver Spring, MD. 33 pp.

ONMS (Office of National Marine Sanctuaries). 2008. Flower Garden Banks National Marine Sanctuary Condition Report 2008. U.S. Department of Commerce, National Oceanic and Atmospheric Administration, Office of National Marine Sanctuaries, Silver Spring, MD. 49 pp.