Marine mammals use sound to communicate, navigate, find mates, and avoid predators. Whales and dolphins in particular rely on a form of sonar, echolocation, to sense their surroundings. But human-caused noise pollution can disrupt, injure, and even kill these animals.

Human activities—including oil and gas exploration, the raising and dismantling of oil rigs, active sonar and explosives testing by the military, the use of noisemakers to deter marine mammals from fishing nets and fish pens, marine experiments that involve the use of loud sounds, and even the increasing level of engine noise from everyday boat and ship traffic can have far-reaching, long-term debilitating effects on marine mammals as well as damage their hearing and even harm or kill them. Governments must ensure that noise producers control and lessen the impacts of their activities on marine mammals.