South Florida Museum in Bradenton warns boaters to prepare for manatee migration season

MANATEE -- Manatee migration might start a little later this year due to an irregularly warm Florida fall, but South Florida Museum officials said boaters and fishermen should still get ready for manatee movement starting Sunday.

Manatees start moving when water temperatures dip below about 68 degrees. Manatees exposed to prolonged cold temperatures start to lose body heat and cannot adequately digest food, which can lead to a potentially fatal condition called cold stress.

Seasonal speed zones take effect Sunday in certain areas where manatee movement is high such as in Tampa Bay. Sea cows in Manatee County typically go up to the TECO Power Plant in Apollo Beach, where discharges keep the waters warm, said Marilyn Margold, director of the South Florida Museum Living Collection and co-chairwoman of the Manatee Rescue and Rehabilitation Partnership.

"Right now, manatees are spread all over the place in the wild," Margold said. "But as the water temperatures begin dropping, they'll be traveling to warm-water spots for the winter. That means manatees will be on the move and boaters need to take extra care to watch out for them, especially in shallow-water areas."

Margold encouraged boaters to follow posted lower speed limits during migration season and for anglers to frequently check and stow gear properly. Roughly 25 percent of manatees are hit by boats in their lifetimes.

"Unfortunately, one of the ways we identify manatees is by the scars on their bodies," Margold said. "So once they're out, we know that it's inevitable, it's just a matter of them learning to move away from that sound."

Even after learning to avoid the sound of engines, manatees sometimes can't avoid fast-moving boats. The large mammals are slow and don't have the best eyesight.

"At best they can move 20 mph for short distances so they're not necessarily going to be able to respond as quickly," Margold said. "They're also more difficult to see, because they're gray in color, they are slow-moving and they're submerged. The boater isn't as likely to see them, which is why it's so important to pay attention to those manatee boating zones."

The South Florida Museum is the home of 67-year-old Snooty, the oldest manatee in captivity. The museum is also housing three other sea cows now in rehabilitation for cold stress.

Mayakklemore, found in the Myakka River in January 2014, should be ready for release within the next few months.

Younger manatees Ice Cube and Sarasolo have been at the museum since July after receiving initial treatment at Tampa's Lowry Park Zoo for cold stress last winter.

Margold said all recovering manatees are doing well and officials hope they will be ready for release soon because the museum tank is at capacity.

"We know Mayakklemore will be going home soon and there's a possibility that Ice Cube could be ready this year as well," Margold said. "That would be a good thing because that would open up more space for other manatees that need to be rehabilitated. That's especially important this year because we're in a strong El Niño year and could see a higher-than-usual number of cold stress manatees."

Biologists from a variety of organizations counted more than 6,000 manatees scattered across Florida during an aerial count in February, about 1,000 more than the previous record set in 2010.

Kate Irby, Herald online/political reporter, can be reached at 941-745-7055. You can follow her on Twitter@KateIrby

This story was originally published November 12, 2015 at 6:02 PM with the headline "South Florida Museum in Bradenton warns boaters to prepare for manatee migration season ."