(News-Press.com) - Manatees are making their annual spring migration to coastal areas, where they feed on sea grasses and rest in the warm waters.
Also called sea cows, manatees are warm-water marine mammals that are more susceptible to illness when water temperatures drop below 68 degrees. During winter months, when water temperatures can sometimes dip into the 50s, manatees seek refuge in smaller rivers and creeks — which stay several degrees warmer, on average, than coastal waters that are more exposed to cold winds and fronts.
Spots like Manatee Park on the Orange River near Interstate 75 are magnets for wintering manatees as a Florida Power & Light plant discharges warm water into the river. Hundreds can sometimes be seen swimming and resting in the man-made refuge.
Warmer conditions in the spring send sea cows back to the coast, where they feed, socialize and roam bays and beaches. Water temperatures in the Gulf of Mexico have risen to 73 degrees off the north end of Fort Myers Beach, according to the Sanibel-Captiva Conservation Foundation.
Spring also brings warm-weather boating zones to places such as Estero Bay, which is about 15 square miles and stretches from Fort Myers Beach to Bonita Springs. Summer boating zones went into place April 1 and remain through Nov. 15. While the bay is mostly open to boaters during the winter, nearly all of it is considered a slow zone for manatee protection over the next seven months.
Speed limits in most of coastal Lee County are 25 mph in boating channels and open bays. Slow zones require boaters to keep their vessels off plane, or slow enough as to not make a substantial wake. The actual speed can vary between boats as different designs create wakes at difference speeds.
The zones were created by the state after manatee advocacy groups filed lawsuits, mostly in the 1990s, over what they said was a lack of protection for these marine mammals. The issue was so controversial that dock permits for houses and condos were not issued for years in the Lee County area.
Manatee zones in Collier County are in place year-round, so boaters don't need to pay attention to seasonal shifts in April and November.
In Lee County, manatee slow zones in the Caloosahatchee River, Matlacha Pass, the bayside shorelines creeks and bays of Sanibel Island, and the bay waters from the north end of Fort Myers Beach to Julies Island are in place year-round.
Summer slow zones are now in place for the following:
• Pelican Bay on the bayside of Cayo Costa State Park
• Safety Harbor at the north end of North Captiva Island
• Bayside shoreline of Captiva and Buck Key
• St. James City canals
• South side of St. James City to Chino Island
• Hurricane Bay and Bayside Estates canals
The summer zones expire Nov. 15, although manatees may make their winter migration earlier or later than that date — depending on weather conditions and the number of cold fronts that hit the region. Maps and more information on boating zones can be found at myfwc.com.