 COLD SNAP COULD BE DETRIMENTAL TO MANATEES Palm Beach Post -- Friday, January 5, 2001 By: William M. Hartnett, Palm Beach Post Staff Writer FORT PIERCE - Plunging temperatures haven't stopped manatees from gathering in popular viewing spots such as the one on Moore's Creek, but they do have scientists worried that the prolonged cold spell could pose yet another threat to the hapless creatures. Though blessed with an immune system so hardy that "they could teach us a lot about ourselves," they are particularly sensitive to cold water, said researcher Greg Bossart. The director of marine mammal research at Harbor Branch Oceanographic Institution compared the effect of cold water on manatees to that of AIDS on humans. When water dips below 65 degrees for more than 72 hours, manatees that aren't killed immediately by cold-induced stress often begin showing ill effects a week to three weeks later, Bossart said. With temperatures in the Indian River Lagoon regularly having dipped into the 50s in the past week, conditions are "very concerning," he said. "This poor species is being hit from all ends," Bossart said. Indeed, manatees are under nearly constant human assault - sliced by boat propellers, sickened by polluted runoff and chased out of their habitat by development of coastal areas. But a more indirect human intervention in the manatee's world is what makes extended cold spells so threatening. In the winter, discharge of heated water from power plants and factories draws manatees to areas that would otherwise be too cold for their taste. Over the decades, the animals have been conditioned to seek out the same oases year after year, passing the knowledge on to their young and stretching their winter habitat farther north than is natural. As long as the power plants were running and their warm discharges flowing, that wasn't necessarily a bad thing, said Kent Smith, a biological scientist with the state's Bureau of Protected Species Management. "It's a two-edged sword," Smith said. "There's more habitat, but it's habitat in areas that put them at risk for cold stress." Such risk is present with ever-increasing frequency, Smith said, as older power plants close or move to an intermittent operation schedule, making them an unreliable source of warm water. Wildlife officials and power companies are left in an unenviable bind. No one wants to harm an endangered species, but how do you justify operating an expensive plant solely for the benefit of manatees, and often to the detriment of sea grasses and other fragile pieces of the environment? "Once again," Bossart said, "man raises his ugly head and is responsible for decimating the species." As a temporary measure, some power companies have included in their manatee protection plans a provision to switch on a dormant plant if the surrounding water temperature fall below a certain point. That's the case in Fort Pierce, said Camille W. Sewell, curator of the Manatee Observation and Education Center. The animals are drawn to the center by the warm discharge from a nearby Fort Pierce Utilities Authority power plant. Despite the cold, Sewell said, 15 manatees were spotted there on Tuesday and a handful showed up Wednesday, including a baby sea cow that delighted onlookers. To avoid further altering manatee behavior, wildlife officials have discouraged the construction of new plants or factories that discharge heated water. Still, a long-term solution remains elusive. Smith said power companies, biologists and wildlife officials are studying the problem and considering ideas such as artificial warm-water preserves where plants have shut down. Whatever the outcome, he said, it better come quickly. With deregulation of the state's power industry looming, some worry the sweeping changes it likely would bring could devastate the manatee population. A widespread change in plant operations could be disastrous, Smith said, because manatees have proven slow to adapt to changes in their habitat. Manatees that have gathered near a plant's warm discharge for years won't leave just because the tap has been switched off, Smith said. They'll just wait. And freeze to death. "The tough-love concept of just shutting plants down and letting the manatees fend for themselves is not a viable alternative," Smith said. "We can't just pull the carpet out from under them." Copyright (c) 2001, The Palm Beach Post |