The increase in deaths is extreme. It’s more than twice the number of deaths recorded just one year earlier: 354 manatees died in the same period in 2020 (while a total of 637 died over the course of the entire year), according to the FWC.
The record die-off constituted an “unusual mortality event,” or a sudden surge in deaths of a species. This year’s die-off was primarily due to starvation, with a spike in boat strike deaths in the summer, the FWC said in its most recent manatee mortality report.
Once the Atlantic Ocean’s waters warmed up in spring, this year’s starvation deaths declined as the manatees dispersed instead of staying in crowded areas with low seagrass, the FWC said.
This year, in general, has been far from typical. Seagrasses will continue to die if their source of sunlight is shaded out by toxic algal blooms, which can cause manatees to overgraze the same patches of grass and prevent it from regrowing, manatee researchers told CNN in May.