NEW YORK - New Yorkers are known to head south to vacation, but at least one Floridian had an urge to come north to see the big city.

Marine preservationists said a manatee had swam up the Hudson River past Manhattan's Chelsea neighborhood and then 100 miles upstate. It was the first confirmed sighting of the mammal in New York in 10 years.

The manatee was filmed by boaters late last month in New Jersey and Delaware and has since been spotted by at least five different outdoorsmen up the Hudson, said Julika Wocial, a supervisor in the rescue program at the Riverhead Foundation for Marine Research and Preservation.

Manatees, also known as sea cows, can travel as much as 50 miles a day but are also known to laze about. "Some of the people that saw it described what's known as 'logging', or raising its big back up and swimming extremely slowly," said Wocial. The mammals live in both salt and fresh water.

Environmentalists and some biologists have said animals such as salmon, locusts and warblers have extended their ranges north as climate change makes the world warmer.

But experts said it is hard to draw any conclusions about this species from only one manatee swimming north even though ocean temperatures in the Northeast hit record highs last August. "It's impossible to tell," said Wocial. "They are known to take trips in the summertime."

Manatees mostly live in Florida waters and are rarely seen off the Carolinas. Nicole Adimey, a biologist at U.S. Fish and Wildlife in Florida said the manatee seems healthy and the government will not make any attempt to capture it unless it stays in New York till fall, when the Hudson would be too cold for it to survive.