What are the dangers facing whales and dolphins?

  • dead harbor seal caught in gill netPredators
  • Diseases and parasites
  • Environmental pollution
  • Habitat degradation
  • Commercial fishing, intentional, overfishing, or as incidental by-catch
  • Harassment by well-wishers, whale watching and feeding dolphins from shore
  • Collision by ships
  • Sportsmen hunting
  • Nets
  • Competition of food
  • Noise pollution

Can dolphins be killed by kindness?

Yes! Some boat tour operators in places like Florida, South Carolina, and Texas offer charter trips to feed wild dolphins. Beachgoers and fishermen also feed wild dolphins that come close to shore. These dolphins may become dependent on the handouts, most of which is not healthy dolphin food. They have been fed hot dogs, candy bars, beer, and baited fish hooks.

In a study of six female wild dolphins routinely fed by tourists in western Australia, scientists found that these mothers did a poor job passing on their hunting skills to their offspring. Only five of the seventeen dolphins born to this group survived. Some starved to death; others were struck by boats; others were attacked by sharks.

What is the most endangered great whale?

right whale tailAccording to authorities at the Stellwagen Bank Information Center, the northern right whale is one of the most endangered mammals in the world. Biologists estimate that 80,000 of these whales once roamed the oceans. But the whales' slow speed and their large stores of blubber and oil (which made them float after they were killed) made them the preferred prey of whaling captains. The name, right whale, was inspired by the fact that they were the "right" whale to catch. Whalers slashed their numbers from tens of thousands to about 50 before they were finally protected by international treaty in 1935.

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. Since 1970, 14 of 40 documented right whale deaths were caused by collisions with ships. Two other deaths were attributed to entanglement in fishing line or nets.

How are mariners and researchers trying to help right whales survive?

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.

(source: Seabits, New England Aquariumís on-line monthly newsletter, July, 1998 and The Gulf of Maine Times,Gulf of Maine Council on the Marine Environment, Fall, 1997)

Photo Credits

  1. Nan Hauser & Hoyt Peckham, CCRC 
  2. Bill Curtsinger Photography