Seaweed Outbreak

Controlling the algal blooms

For more that 10 years, the main sewage pipeline on Majuro Atoll has been slowly deteriorating causing untreated sewage onto coastal reefs. Eutrophication is an aquatic environment's natural reaction to the excessive addition of nutrients.

Algal blooms are common in areas with large populations with heavy pollution.

The nutrient-rich marine environment provides the perfect condition for seaweed growth. In addition to the raw sewage, coastal communities are also prime contributors. The lack of proper waste disposal in certain communities has left the people to improvise and use the ocean as rest rooms.

Also, some individuals house pigs near the shoreline, rinsing their waste into the ocean. The overgrowth of seaweed spanning a long distance from Jenrok to Ajeltake is an environmental nuisance. it is an invasive organism. The two species were identified as Hypnea musciformis and Gracilaria edulis.

Mitigation opportunities include accelerating plans to fix the sewage outfall pipe in Delap; engaging farmers and local residents to use seaweed for compost; the Coastal Management Advisory Council has propsed closing ocean side reefs to fishing for seaweed-eating fish so that their populations expand and reduce the amount of seaweed; MIMRA's aquaculture sector is considering farming algea-eating sea urchins to counter act the overgrowth of seaweed.

G. Edulis, above, and H. Musciformis, below, which are two of the algae that are common sights on Majuro's reef flat. Below, brown algae outbreaks that continued in 2015.

© 2018 Marshall Islands Marine Resources Authority. All Rights Reserved.