The deaths appear to be a resurgence of a grim series of manatee deaths that occurred in the area between 2012 and 2015, according to the Tampa Bay Times. More than 150 manatees were found dead in a trend that began after a bloom of algae turned lagoon waters a dark brown color, killing off the sea grass that the manatees eat. Without their usual grass, manatees began eating red seaweed.
Both the most recent dead manatees and the ones that died between 2012-2015 had guts filled with the seaweed, with not much sea grass.
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