DURHAM, N.C., Feb. 8 (UPI) -- Stress on whales from low-frequency ship noise lessened during a lull in ship traffic resulting from the Sept. 11, 2001, terror attacks, U.S. researchers say.
Scientists analyzed underwater noise levels in Canada's Bay of Fundy during a period of reduced ship traffic following the attacks and compared stress-related hormone metabolites in the fecal samples of right whales before and after the attacks.