BRUNSWICK, Ga. -- The manatee migration began and boaters from Florida heading north toward Georgia are urged to steer clear of the endangered species.

Only 3,000 manatees remain in the U.S. and they are protected by state and federal laws.

The Georgia Department of Natural Resources estimated that a quarter of manatees killed in Georgia die in boat collisions.

Officials say boat collisions are most likely to occur in shallow water, particularly around docks and at the edge of marshes.

Manatees frequent these areas in places like tidal rivers and estuaries, and sometimes come close to shore, where they graze on marsh grass and other aquatic plants.

Kristina Summers, a spokeswoman for the Department of Natural Resources, said following boater safety regulations in these areas can reduce the risk of collisions.

"Boaters should also watch for manatee backs, tails, snouts and footprints -- a series of round swirls on the surface caused by a swimming manatee's tail," Summers told The Brunswick News.

Boaters should also beware of mothers nursing their calves, since the young are dependent on the mother for one to two years.

Manatee calves are about four feet long at birth and weigh about 60 pounds.