'Perfect Storm' caused Siesta lagoon fishkill
SIESTA KEY - The massive fish kill in a Siesta Key lagoon recently was apparently caused by a 'perfect storm,' according to officials.
Thousands of fish caught in the mangroves of that lagoon on the southern tip of Siesta Key were killed by changes in the water. In the week of November 15th, the Florida Fish and Wildlife Commission received 17 reports of fish kills from Heron Lagoon residents. The Herald-Tribune took a water sample and confirmed it was not red tide.
Sarasota County officials determined that it is more than likely that the lagoon had an algae bloom during the recent cold snap. When algae dies off, it sinks to the bottom of the water column and begins to decay, which reduces the levels of dissolved oxygen in the water. That 'perfect storm' causing the lower levels of dissolved oxygen can lead to fish kills.