After more than 50 years of protection of right whales, biologists estimate that there are still only about 300 northern right whales. The National Marine Fisheries Service states that to avoid extinction, only four right whales per decade can die from other than natural causes. Today, collisions with ships are the leading cause of death of the slow-moving right whales. Two other deaths were attributed to entanglement in fishing line or nets. They are patrolling right whale calving grounds along the southeastern coast of the United States, between Brunswick, Georgia and St. Augustine, Florida, and their feeding grounds in the Gulf of Maine.
Many organizations collaborate to track the whales by ship, airplane, and helicopter.
When they locate right whales, they relay that information to ships. The Right Whale Early Warning System makes daily flights over the breeding grounds between December and May and continue to monitor their locations when the whales move to feeding areas off the coast of Massachusetts during late winter or early spring. The National Marine Fisheries Service directs all ships to stay 500 yards from the whales. The Navy, which conducts training exercises from its base in Mayport, Florida, has moved some of its activities away from the calving grounds. Fishermen and many lobstermen have modified their fishing gear so their lines will break if a whale becomes entangled in them.