Would-be rescuers ended their search Friday for a manatee that strayed an unprecedented 700 miles up the Mississippi River, leaving the warm-water mammal to an uncertain fate far north of its natural range.
The manatee, which had been spotted several times since Sunday along the Memphis riverfront, eluded a rescue team that had hoped to haul it by truck to Florida.
Biologists were unsure if the animal could find its way back to warmer waters or how long it could survive so far north.
"I don't know where it would find warmer water around there. Hopefully, it's headed south," said Nicole Adiemy, a manatee specialist with the U.S. Fish and Wildlife Service. "It just depends on the water temperature the whole way down."
Manatees, an endangered species, generally cannot thrive below 66 degrees, and their natural range is the coastal waters of the southeastern U.S. Water along the Memphis riverfront was 60 degrees or lower in recent days.
A team made up of police, Coast Guard personnel and marine mammal specialists from Florida searched for two days, using boats with sonar and a helicopter with thermal imaging equipment. The last reported sighting of the animal, believed to be up to eight feet long and 1,000 pounds, was Wednesday afternoon.
Biologists said there was no previous record of a manatee traveling so far up the Mississippi, though they have been known to enter the mouth of the river from the Gulf of Mexico. This summer, a manatee was spotted near New York City.
Lt. Ed Vidulich of the Memphis harbor patrol said the swift Mississippi current could have carried the manatee well downstream while the search was under way.
"If he's going south, people in Mississippi might be looking out for him. People in Louisiana might be looking for him," Vidulich said.