Ship noise increases stress in right whales

Science : A mere 475 right whales summer in the western North Atlantic Ocean, and they have much lower reproduction rates than right whales that summer near Antarctica. One reason for that may be noise-induced stress. Rosalind Rolland of the New England Aquarium in Boston and colleagues report in the Proceedings of the Royal Society B that reduced ship traffic in the Bay of Fundy in the aftermath of the September 11, 2001, terrorist attacks resulted in a 6-decibel decrease in underwater noise, specifically low-frequency noise. Baleen whales, including right whales, use low-frequency sounds to communicate, and prior studies have shown that they change their behavior and vocalizations when noise increases. Rolland found that the Bay of Fundy’s period of quiet was associated with a significant reduction in stress-related fecal hormone metabolites excreted by the whales.