The North Atlantic right whale is one of the world’s most endangered whales. Named by fishermen as the “right” whale to hunt due to its tendency to swim close to shore and float when dead, the species was decimated by commercial whaling in the early twentieth century. Today, only about 400 right whales remain.
The National Marine Fisheries Service has previously stated that the “loss of even a single individual may contribute to the extinction of the species.” Despite its protected status, humans continue to post the greatest threat to this whale’s survival. In 2011 alone, at least four adult right whales were killed, including two from injuries related to entanglement in fishing gear and one as the result of a ship strike.
Right whales are very large, but travel at a leisurely pace – no more than about 10 miles per hour. This becomes a serious problem when their migration from the Gulf of Maine to the coasts of Florida and Georgia takes them through some of the busiest shipping lanes in the world. When ships run into these whales, they cause severe, often fatal damage. Even if the whale doesn't die on impact, it often dies from loss of blood within hours—especially if a segment of the tail is severed or a vital organ gets punctured.
Nets and fishing lines can pose serious threats to whales. Floating lines between lobster or crab traps are particularly dangerous, since they can form loops that whales can be caught in. If the lines were to lay flat on the ocean floor, they would not be dangerous to whales. When whales become tangled, the lines can cut into their blubber and limit their ability to feed and swim, leading to a long, painful and unnecessary death. Even those that manage to break free can be susceptible to infection or death from their injuries. The National Marine Fisheries Service has cited entanglements in commercial fishing gear as one of the most significant threats to right whales.
The ocean may seem peaceful to us, but it can be a noisy place. As more noise from shipping, drilling, sonar testing and other human sources add to the “acoustic smog” in the ocean, it becomes harder for whales to communicate with one another. Some sonar can even cause physical damage to whales.
As the climate  changes, so do the oceans. The effects of ocean acidification are already being seen in some places, and threaten to cause significant damage to the marine food chain.