Green Sea Turtle Welfare: Herbivory, Fibropapillomatosis, and Recovery

Green sea turtles are the only herbivorous sea turtle and play a key role in seagrass ecosystem health. Their recovery is complicated by a tumour disease linked to water quality decline.

Key Facts

Green sea turtles are the only sea turtle that feeds primarily on seagrass and algae as adults
They are listed as Endangered globally, though some populations have recovered significantly with protection
Fibropapillomatosis — a tumour disease — affects up to 70% of turtles in some Hawaiian and Florida populations
The disease is linked to algal blooms caused by nitrogen pollution from agriculture and sewage
Green turtles were historically hunted for their fat, used to make turtle soup

Welfare Considerations

Fibropapillomatosis causes proliferating tumours on the eyes, flippers, and internal organs of green sea turtles. Eye tumours cause blindness, impairing foraging and navigation. Internal tumours cause organ failure. Affected turtles suffer prolonged decline before death. The disease appears linked to immune suppression from pollution-related algal blooms, meaning reduced water quality directly causes welfare harm. Rehabilitation of affected turtles involves surgical tumour removal with variable outcomes, illustrating both the scale of the problem and the commitment of conservation workers.

What You Can Do

Reduce nitrogen pollution by choosing low-fertiliser gardening and supporting agricultural runoff controls
Support green turtle nesting beach protection in Costa Rica, Florida, and the Indian Ocean
Donate to turtle rehabilitation programmes that treat fibropapillomatosis
Back seagrass restoration projects that provide critical green turtle feeding habitat