Emilio Sosa with the Florida Marine Research institute gave a presentation on the cause of lesions found on fish in the Indian River Lagoon. The culprit is a toxic fungus known as Aphanomyces invadens. This fungus prefers low salinity and will affect almost all types of fish. In 1998 large freshwater releases from Lake Okeechobee into the St. Lucie River and the Lagoon created low salinity conditions allowing the fungus to thrive and attack large numbers of fish already stressed by the low salinity conditions.