Strange lesions are showing up in coral trout in the Great Barrier Reef in Australia.
In a new paper in the journal PloS One researchers found that 15% of reef fish tested showed signs of melanomas. This is a high occurrence, given that many of the fish with this condition may have already been eaten by predators or perished due to the illness.
This is the first time skin cancer has been documented in a wild marine fish species, but in the laboratory another species exposed to high UV radiation showed similar lesions, and they lived greatly reduced life spans.
The authors note that the occurrence of the melanomas was likely due to increased UV radiation and the proximity of the fish to the hole in the ozone layer which occurs over portions of Australia and Antarctica. The people of Australia already suffer huge health risks from skin cancer, topping the world in the occurrence of this illness.
These results are concerning because coral trout are an important commercial fish species, and they may suffer population level impacts if these rates continue. One third of all coral reef fish are already threatened with extinction due to the impacts of climate change on coral reefs, their home. Added stresses such as skin cancer could be the nail in the coffin for some species.
It’s important to figure out if skin cancer is occurring in more fish in a larger area, and what the risks are globally for marine life from UV radiation. We obviously can’t put sun-block on every fish in the ocean, but we can limit emissions of ozone-depleting gases like chlorofluorocarbons (CFCs), a refrigerant, as well as greenhouse gases that drive climate change which was also recently shown to threaten the ozone layer.
We are all in this together, so for the sake of fish and people we need to protect our thin layer of atmosphere.