Federal and state workers Thursday freed a 2-year-old right whale calf entangled in ropes off the coast of Georgia.

It was the fifth endangered mammal rescued since December in waters off Georgia and Florida.

Rescuers used a pole-mounted knife to cut two thick, black synthetic ropes on Thursday. One rope was wrapped around the calf's head and the other trailing out both sides of its mouth.

The rescue took more than four hours in 2-to-2-foot seas.

Only about 350 to 400 North Atlantic right whales remain, putting them among the most highly endangered of all whales.