Shhhh, the whales are resting

A Danish-Australian team of researchers recommend new guidelines for noise levels from whale-watching boats after having carried out experiments with humpback whales. They exposed the whales to different levels of boat-engine noises while observing the current guidelines for whale-watching – keeping 100 metres distance, for instance – while monitoring the whales’ behavior closely with a drone camera. The researchers concluded that the noise level from a boat’s engine should stay below 150 decibels.