JACKSONVILLE, Fla. - After scientists determined that a young North Atlantic right whale died last month after becoming entangled in gillnet gear, the NOAA Fisheries Service will prohibit all gillnet fishing off Georgia and northeast Florida through the end of the endangered mammal's calving season. The closed area, known as the Southeast U.S. Restricted Area, extends from Savannah, Ga. though Sebastian Inlet, Fla., and out to 80 degrees west longitude. This closure begins Feb. 15 and extends through midnight March 31.

This is a serious situation and we must take this action immediately to protect right whales," said Dr. Bill Hogarth, assistant administrator for NOAA Fisheries Service. "This closed area includes the only known calving ground for right whales and we need to protect them while they utilize this area."

Only about 300 North Atlantic right whales remain and the species is listed as endangered under the Endangered Species Act of 1973.

Under the Atlantic Large Whale Take Reduction Plan, if a whale is seriously injured or killed, the NOAA Fisheries Service is legally required to close the area to the type of gear that caused the injury or death.

The whale, the second to die off the coast of north Florida recreational boaters found this year, was towed to a remote Duval County beach, where scientists from the Marine Mammal Stranding Network examined the carcass and took samples.

The examination team said it found several wounds near the whale's tail that are consistent with entanglement in gillnet fishing gear and shark bites. While the cause of death has not been determined, NOAA Fisheries says, "all available evidence suggests that entanglement and injury by gillnet gear ultimately led to the death of this right whale calf."

The first dead right whale calf was reported on Jan. 10 and preliminary findings suggest that the whale was killed by a ship strike.

Anyone who spots a right while is asked to call NOAA Fisheries' Stranding Hotline at (786) 382-9585. NOAA Fisheries law enforcement division has a hot line to report illegal fishing or other violations of conservation law: (800) 853-1964. People reporting violations may be eligible for a reward.

But, in December, the fisheries service launched an extensive effort to untangle a right whale. They pulled off about 30 pounds of trailing line but did not get it all. The tracking buoy on the animal broke free and the whale hasn't been seen again.