Florida’s manatees gently glide through the state’s rivers and along coastal beaches like great, grey footballs, endearing themselves to residents and tourists alike. The half-ton, whiskery mammals are celebrated throughout the state on T-shirts, license plates, and with huggable stuffed toys in their likeness. During winter, tourists and locals converge on inland waterways, donning dive gear and plunging into chilly waters, when manatees migrate inland in massive numbers each year. Enraptured humans hope simply to snap photos of the sea cows moving through the water lazily with curious calves. The peaceful animals exude an aura of complete contentedness, seemingly unafraid. But waterways on the state’s Atlantic coast now are nightmarish for the thousands of manatees seeking refuge from cold there when ocean temperatures dip below 68 degrees. Long their winter sanctuary, the coastline has become a place of starvation. As of Jan. 28, 97 manatees had died in 2022, with …