In a newly completed study of fish suffering skin lesions, researchers observed a correlation between the malady and the chemical footprint of the spilled oil found in the fishes' livers and muscles.
Scientists say their analysis ruled out the possibility that the uptick of these skin lesions in 2011 were the result of other pathogens or oceanographic conditions.
"The higher rates of skin lesions in 2011 vs. 2012 were not due to an outbreak of pathogens or abnormally low salinity, and thus the hypothesis that DWH was responsible for the higher rates of skin lesions remains viable," explained lead researcher Steven Murawski, a professor of marine ecology at USF's College of Marine Science.
To carry out the study, Murawski and his colleagues at USF partnered with the Florida Institute of Oceanography and the Florida Fish and Wildlife Research Institute in 2011 and 2012. Together, the scientists collected, dissected and observed the health of various fish species -- especially red snapper and other bottom feeders -- from the northern regions of the Gulf of Mexico.
"Surveys revealed that by 2012 the overall lesion frequency had declined 53 percent, with the severity of lesions also declining" said Murawski -- further proof that the lesions were the result of an episodic event.
Their worrisome findings were recently detailed in the latest issue of the journal Transactions of the American Fisheries Society.