Toxic red tide has killed a record number of endangered manatees along the Southwest Florida coast.
With no sign of when the deadly algae bloom might abate, the preliminary death toll of 174 is likely to continue rising, state and federal wildlife managers said Monday. The number already has topped a previous red tide high of 151 in 1996.
Its really hard to make any kind of prediction on it, said Kevin Baxter, a spokesman for the Florida Fish and Wildlife Conservation Commission. Each outbreak is a little different.
This red tide covers roughly 70 miles from Sarasota south to Pine Island Sound, where the majority of deaths have been recorded in warm waters where the sea cows congregate during the winter. Sampling has found the algae, which also has triggered sporadic fish kills, as far south as Collier County at times.
Baxter said most FWC scientists believe the manatees are dying after eating sea grass, a staple of their diet, that the algae has settled on. Once afflicted, they lose coordination and the ability to swim upright or lift their heads out of the water to breathe.
If reached early, stricken manatees can be saved, Baxter said. A dozen have been rescued so far, transported to area zoos where workers hold their heads above water until the effects fade. The FWC asks anyone in the impact area to report struggling or dead manatees to the Wildlife Alert Hotline at 888-404-FWCC (3922).
Its not yet clear what impact the toll might have on manatee protection. The manatee has more than doubled its population over the last few decades, with estimates of more than 4,000 now in state waters. The U.S. Fish and Wildlife Service, petitioned by boating and development interests, has begun working on a proposed rule to reclassify the manatee from endangered to threatened, a move that could potentially slow or halt the expansion of slow speed and idle zones in state waters.
Despite the larger population, environmentalists argue the sea cow remains highly vulnerable to boat strikes, cold weather and red tides. Development also has destroyed much of its natural habitat and the phase-out of coastal power plants could reduce warm-water havens that protect them during cold snaps.
Leopoldo Miranda, assistant regional director of the services southeast office, said the agency would work with state scientists to assess the long-term impact of the red tide and a deadly 2010 freeze on the sea cows.
Our priority remains the animals, not the process, he said in a written statement.
The FWC first detected the red tide in September near Tampa. It has waxed and waned since, with its highest and deadliest concentrations in Lee County waters. It remains unclear exactly what triggers the toxic blooms of phytoplankton. While some factors are natural, such as water temperatures, some scientists believe the outbreaks are worsened by agricultural runoff containing nutrients that feed algae growth.