Fibropapillomatosis in Green Sea Turtles of Maunalua Bay
The Honu (Hawaiian Green Sea Turtle) holds major cultural significance in Hawaiian culture. The Honu is a symbol for longevity, safety, and mana (spiritual energy). The population of Honu surrounding the Hawaiian Islands is classified as least concern despite its grim global outlook. However, an increased frequency of Fibropapillomatosis (FP), a tumor-like growth, is being spotted on their carapace (shell), neck, and face. FP has been identified in every species of turtle, however, it has only reached the panzootic state in Green Sea Turtles. Turtles that have contracted FP show signs of immunosuppression, chronic stress, and chronic inflammation such as anaemia, lymphocytopenia, neutrophilia, monocytosis, hypoproteinaemia and hyperglobulinaemia (Aguirre et al, 1995, Work et al, 2001, dos Santos et al, 2010, Page-Karjian et al, 2014, Jones et al. 2016). Current Research also suggests that there is a strong association between FP and herpes-like virus, Chelonid herpesvirus 5 (ChHV5), indicating that ChHV5 is present in turtles diagnosed with FP as well as turtles showing no signs of FP.
Despite an increase in the amount of research being done regarding FP on oahu (mainly in Kane'ohe bay), there is a scarcity of surveying and monitoring in Maunalua Bay. Our aim is to document and record the severity of FP in Honu of Maunalua Bay, measure the growth rate of lesions, and work with local institutions to understand the effect of FP on blood biochemistry.
FP has yet to be seen in pelagic juveniles, and is thought to be contracted once the turtle has found its coastal habitat. When inhabiting their neritic zone, they are in a new environment, where they're exposed to changes in diet, population density, and new pathogens. The same way that we, as humans get sick when we travel to a new continent. This immunosuppression coupled with close contact to already infected individuals causes the turtles to be more susceptible to infection of FP and ChHV5.
Our main survey sites are Koko Craters and the Baby Barge Artificial Reef. These sites were chosen due to their functionality as turtle cleaning stations. Honu come to certain ledges and coral bommies to both sleep and get cleaned by the range of cleaner fish that inhabit the cleaning zones. The ledges and bommies at Koko Craters are at 10-12 meters of depth, which allows for both snorkelling and diving data collection. Baby Barge Artificial Reef is at 20-25 meters of depth, which means surveys are done via SCUBA. Turtles are identified by species and sex, and then classified into 4 categories: 0) no signs of FP, 1) Light signs of FP, 2) Moderate FP, 3) Severe FP. Growths are then measured via photography
*Do not touch or harass turtles as it is illegal under state law. If you are looking to handle turtles make sure you are authorized and have the necessary permits*