Florida Making More Room for Manatees
OutdoorHub 02.16.12
If you restore Fanning Springs to its historic depths by removing sediment, more manatees will be able to use this shimmering spot on the Suwannee River. That was the idea behind the project to clear the bottom of Fanning Springs, and it quickly came true.
“As the project was going on, more and more manatees were showing up at Fanning Springs. We went from two to four manatees to eight or 12,” said Ron Mezich, who works on manatees and aquatic habitat at the Florida Fish and Wildlife Conservation Commission (FWC). “Fanning Springs may feel cold to us, but it is 70 to 72 degrees, and for manatees in wintertime, it is a warm-water refuge. Manatees can’t survive for long in water below 68 degrees.”
The recently completed project to remove sediment from the springs was a cooperative effort among the FWC, The Nature Conservancy and the Florida Department of Environmental Protection, which manages Fanning Springs State Park.
From early November 2011 through early January 2012, underwater cleaning of the springs was done by a scuba diver using a hand-held device resembling a giant vacuum cleaner. Hand cleaning was the preferred method to minimize disturbance to the springs’ waters and preserve any artifacts found in the removed sediment. Park staff and volunteers sifted through more than 500 cubic yards of removed sediment and found boards and an ash rake from a former sawmill on the site, as well as coins like a liberty half-dollar and buffalo nickel.
With the project completed, Fanning Springs is 2 to 3 feet deeper in some areas and able to provide additional habitat for manatees to escape winter’s cold. Recently, Florida manatees have been hit hard by cold weather, with documented manatee deaths due to cold stress at their highest levels, including 112 cold-related manatee deaths in 2011, 282 in 2010, and 56 in 2009. Previously, manatee deaths due to cold stress averaged 30 per year.
“Conservation of warm-water habitats like Fanning Springs is critical to the long-term conservation of the manatee, and a priority for the FWC and our partners,” Mezich said. “Florida’s springs provide warm-water habitat for about 20 percent of the manatee population.”
Mezich said the recent observation of more manatees migrating into Fanning Springs was probably attributable to the weather getting chillier, limited access of boats to the springs during construction, and improved access to the springs for manatees.
Fanning Springs is a major attraction in a small rural community. Fanning Springs State Park is a hub of the Suwannee River Wilderness Trail, and local residents and visitors come here for swimming, snorkeling and boating. The FWC encourages visitors to come to the park to see if manatees are using this warm-water refuge. While you are there, the FWC recommends doing your manatee observations from the park’s dock and boardwalk. Boats of all types entering the springs during winter months can disturb and discourage manatees from using this warm-water site when it is most important to their survival. The springs also are prime habitat for mudfish, freshwater flounder and turtles.
Fanning Springs is a second-magnitude spring, producing less than 65 million gallons of water daily. Historically, though, it was a first-magnitude spring, the largest class of springs, with a flow of up to 100 cubic feet of water per second, as recently as the 1990s. The spring’s sediment problems were caused by erosion from its banks, when they were used by people coming there to swim and recreate. The park staff restored vegetation to stabilize those banks, preventing further erosion.
“We’re taking the spring run at Fanning Springs back to a more historic depth contour. Sedimentation caused it to become too shallow,” Mezich said.
