County leads in manatee deaths due to cold

Lee County has the highest total number of manatee deaths in the state for 2026 so far, according to newly released preliminary manatee mortality data from the Florida Fish and Wildlife Conservation Commission (FWC).

FWC’s Marine Mammal Pathobiology Laboratory has recorded 101 manatee deaths in Lee County from Jan. 1, 2026 to July 24, 2026. The next highest number by county is 53 deaths in Brevard County, which recorded the highest number of manatee deaths in 2025 and 2024.

The preliminary data is broken down by cause of death; Lee County had 17 casualties due to watercraft, two perinatal deaths, 15 from cold stress, two from natural causes, 11 undetermined, and 54 that were not necropsied.

One of the reasons that Lee County has such a high number of deaths so far this year is due to a spike in cold stress-related deaths in February, wrote Beth Brady, director of science and conservation for Save the Manatees in an email to the Beacon.

“It is unusual this year as there was an issue where the powerplant in Fort Myers had to shut down unexpectedly,” Brady wrote. “Although FPL did nothing wrong, the lack of warm water caused the death of over twenty manatees due to cold stress.”

Of the 15 Lee County manatee deaths caused by cold stress this year, FWC recorded 14 of them in February. February also had the county’s highest monthly mortality total so far, with 58 deaths.

Of those 58 deaths, 39 manatees were not necropsied. As a result, additional deaths may have been related to the same power plant shutdown but were not confirmed.

Four of the 101 manatee deaths in Lee County were recorded in Boca Grande. There was a manatee death reported on Jan. 31 in Charlotte Harbor with the probable cause recorded as perinatal, which is described by FWC as manatees less than or equal to 150 cm (5 feet) in total length which were not determined to have died due to human-related causes.

The second 2026 Boca Grande death was on March 15 in Gasparilla Sound, where a dead manatee was found to be too decomposed to identify a cause. A second death was recorded on March 24 in Gasparilla Sound and the necropsy results were inconclusive.

On April 27, a dead manatee was verified in Charlotte Harbor but a complete necropsy was not performed.

“The fact that 54 manatee carcasses were not necropsied makes it difficult to determine why the Lee County mortality rate is so high,” Brady wrote. “Although Lee County consistently has one of the highest watercraft-related mortality rates (17 so far this year), indicating that recreational boating is a significant issue in the area,” she added. For the first half of 2026, there were a total of 410 manatee deaths recorded in the state with watercrafts representing the primary cause, not counting undetermined or non-necropsied deaths.

In all of 2025, there were 632 deaths recorded by FWC. In the 2025 preliminary reports for the same period of time, there had been 482 deaths by this point.

“Red tide, cold stress, watercraft and unusual mortality events can cause one county (or multiple counties) to have a large majority of deaths,” Brady wrote. “From 2021-2023, we had an unusual mortality event on the east coast of Florida which caused over 1,200 manatees to die from starvation. There were higher death totals in Brevard and surrounding counties during this time. In 2023, there was a red tide bloom where 85 mortalities were observed across seven counties in southwest Florida. In 2018, there were 288 suspected mortalities from red tide distributed over southwest Florida.”

The whole report, as well as historical reports are at myfwc.com/research/manatee/rescue-mortality-response/statistics/mortality/.