Well, khandon't, maybe ther eis a technical answer. Why not build a giant ship, very wide, with loads of generators and pumps on it, capable of pumping out a large cube of warm water around it? Anchor it on the Misissippi and open the waterways from the lakes s that manatees fleeing the cold will gravitate to the warm bubble of water being maintained around the ship. Then have the ship navigate slowly down the coast of Central and South America, through the Straits of Magellan and around the Horn, up the Pacific coast, generating its warm water space in the water around it as it goes.

Any manatee inside the warm water will turn back toward the ship anytime it hits the boundary layer of cold, and will thus be forced by their own instinct to round the Cape and move up the Pacific coast up to the Sacramento and Stockton deltas where they could be picked up by smaller bubble-of-heat boats to take them up to the areas where the Calla Lilies grow, or whatever it is you're trying to ge rid of -- kudzu? Spanish moss? I forget....

A