Australia Zoo Wildlife Hospital has recently seen an influx in the admission of green sea turtles suffering from an unknown emerging shell disease.
The hospital has treated 49 green sea turtles since December 2021, rescued from a localised area of Hervey Bay and suffering from a shell-melting disease. One further animal was found on the Sunshine Coast.
The marine animals were generally found stranded on the beach or floating offshore.
“The green sea turtles tend to have ulcerated open wounds on their shells and flippers which often lead to the exposure of the underlying bone,” hospital supervisor Dr Ludo Valenza said.
“Dr Emily Kay and the rest of our team is working towards determining the cause of these wounds and the associated systemic infection.
“Although we are still investigating the cause of this illness, we believe that it is linked to diminishing sea grass availability for the turtles which has been exacerbated, but not solely caused, by the recent flooding events.
“We suspect that due to low food supply, the turtles are forced to eat a source of food that generally only contributes to a small part of their diet, and could be causing them to get sick. The shell disease is only what we see on the outside.
“Unfortunately, the turtles have been presenting with very severe gastrointestinal issues..
“So far, 26 turtles are currently undergoing treatment, one turtle has been released back into the wild following a full recovery, and 22 turtles were humanely euthanised due to the severity of this disease.”
Lucky is a juvenile green sea turtle currently being treated at the Wildlife Hospital with this shell-melting illness.
“We’ve been receiving green sea turtles suffering from this disease from the Hervey Bay area, however, Lucky came to us from a different location on the Sunshine Coast, which is concerning as it means that turtles outside of the localised Hervey Bay region could also be suffering from a similar cause,” Dr Valenza said.
“We are treating the affected turtles with antimicrobials to contain the infection and prevent it from spreading,” she said.
The Wildlife Hospital is working with Dr Christabel Hannon of Obelia Consultancy and the University of Queensland to determining the cause of the illness.
“This disease is highly debilitating and can take months for the turtles to recover, and unfortunately sometimes they never do. The cascading effect of this disease on the population of green sea turtles could be catastrophic,” Dr Valenza said.
“Female green sea turtles only breed every three or so years, and with only one in 1000 hatchlings turtles surviving to a mature age where they can breed. Every turtle is vital to the survival of this endangered species.”
Department of Environment and Science principal ranger Steve Hosed said the department would continue to work with leading wildlife experts in veterinary science and turtle rehabilitation to investigate reports of the ulcerative skin disease in green turtles and try to determine the underlying causes so a direct response could be made.
