|credit: K. Jones, James Cook U.|
Sea turtles have no effective immune defense against tumors that grow up to 30 cm across on eyes, flippers, tail, shell or internal organs. Eventually the tumors become so large they prevent the animal from foraging, or they become vulnerable to predators and other infections because of their weakened condition. The tumorous infections seem to be localized to hot spots where there is heavy human activity. Magnetic Island in Cockle Bay is a popular tourist destination on the reef. There half the turtles have fibropapillomatosis whereas less than ten percent of turtles living in Cockle Bay have the condition. Similar herpes tumors are seen in Florida and Hawaii, especially near farming operations on shore. Apparently pollution weakens the turtles immune systems allowing the tumors to grow unchecked. The next step in the scientific investigation of the epidemic is isolating the toxic agent in water samples.