Manatees gather near the outlet where Florida Power & Light Company (FPL) pipes warm the water, at an inactive power plant undergoing renovation works in Riviera Beach, Florida January 7, 2010. With 61 degrees Fahrenheit (16 degrees Celcius) being the minimum temperature that a manatee needs to survive, FPL is helping prevent deaths by turning on the heaters at the plant for the manatees as forecasters predict another pocket of arctic air moving into the southern United States over the weekend. REUTERS/Carlos Barria (UNITED STATES — Tags: ENVIRONMENT SOCIETY ANIMALS)