IRLNews:2021-04-01/Indian River Lagoon Manatee Mortality Update
As of March 26, 2021, a record 573 deceased manatees have been reported to the Florida Fish and Wildlife Conservation Commission (FWC) this year.[3]
The Indian River Lagoon National Estuary watershed has reported 371 manatee deaths to the FWC so far this year.[4]
| County | 2/26/2021 | 3/26/2021 |
|---|---|---|
| Volusia | 16 | 26 |
| Brevard | 168 | 248 |
| Indian River | 13 | 21 |
| St. Lucie | 4 | 11 |
| Martin | 24 | 31 |
| Palm Beach | 29 | 34 |
| Total | 254 | 371 |
Brevard County Manatee Mortality
In the first 85 days of 2021 Brevard County citizens reported 248 manatee deaths to the FWC. These manatee mortalities have met the criteria to be declared an Unusual Mortality Event (UME) by the Working Group on Marine Mammal Unusual Mortality Events, and the U.S. Fish and Wildlife Service has confirmed the UME determination.
There are many factors affecting Brevard's manatee population. All due to human impact.
Natural Migration Interruption
During the winter manatees congregate in the Port St. Johns compartment of the North Indian River Lagoon due to the warm water discharge from the power plant. Manatees would normally migrate south as the water temperature drops, but the power plant's warm water outflow distracts them from their natural migration. While the resident manatee population is estimated at 500 individuals, a 2016 aerial survey counted 1,400 winter manatees population in the PSJ compartment of the North IRL.
Loss of Seagrass
It is estimated that the Indian River Lagoon has lost 54% of the record high seagrass coverage recorded in 2007.[5] Manatees may eat up to 10% of their body weight daily and there isn't enough seagrass growing in the North IRL to feed the unnaturally large population.
The good news is that the Indian River's water temperature is warming up, and the manatees have begun migrating to more fertile areas.
Contact FWC Wildlife Hotline at (888) 404-3922 to report a deceased manatee.
Web Links
- Bloomberg Businessweek: Nobody Knows How to Wean Manatees Off of Power Plants
- FWC: Manatee Mortality Event Along The East Coast: 2020-2021
- NOAA Marine Mammal Unusual Mortality Events
- Winter Manatee Foraging Behavior and the Decline of Seagrass Beds in the Northern Indian River Lagoon USGS 2015
- FWC Update to the Statewide Florida Manatee Abundance Estimate
Documents
- FWC 2021 Preliminary Manatee Mortality Table (PDF 19pp 562KB)
- FWC 2021 YTD Manatee Mortality Table (PDF 1p 113KB)
- Updated Statewide Abundance Estimates for the Florida Manatee (PDF 27pp)
References
- ↑ Updated Statewide Abundance Estimates for the Florida Manatee (PDF 27pp), ISSN 1930-1448, page 5, retrieved 2021-04-01.
- ↑ Federal Register Vol. 81, No. 5 (PDF 28pp), page 2, retrieved 2021-04-01.
- ↑ FWC 2021 Preliminary Manatee Mortality Table (PDF 14pp 562KB), retrieved on 2021-04-01.
- ↑ FWC 2021 YTD Manatee Mortality Table (PDF 1p 113KB), retrieved 2021-03-07
- ↑ Dr. Chuck Jacoby, SJRWMD, 2020 Water Quality Presentation Video, retrieved: October 11, 2020
