On Sunday, a manatee that had been previously rescued from Cape Cod, Massachusetts, waters died before he could reach Florida Sea World, where he was to be rehabilitated in order to be afterwards sent back into the wild.

Chris Cutter of the International Fund for Animal Welfare (IFAW), one of the largest conservation charities worldwide, has stated that the cause of death was to be investigated.

The manatee was pulled out of the cold waters on October 11, after federal, state, local and nonprofit officials tried for several hours to catch the mammal, which managed to escape and hide under boats each time the rescue team came close to it.

Also known as the sea cow, the large marine mammal is generally found in warm estuarine waters, since he cannot survive at below 15°C temperatures.

Rescuers informed that Dennis’ (as he was dubbed) temperature had fallen 20 degrees below normal, which rendered him incapable of eating.

After having been pulled out of the waters, he was put on a Penske moving truck that was supposed to take him to Florida.

Unfortunately, Dennis did not survive the twenty-hour drive to the Orlando Sea World.

Mainly herbivores, manatees usually graze in shallow waters and spend half of their day sleeping underneath the surface.

It has been estimated that a number ranging from 1,000 to 3,000 such marine mammals are currently inhabiting Florida.

Manatees have been known to be able to swim approximately 30 km per hour and live up to about 60 years.