The document discusses key developments in 2006 related to understanding the impacts of ocean noise on marine life. It highlights that chronic exposure to moderate noise levels, such as from shipping traffic, is increasingly recognized as a major threat due to its potential to cause masking of communication and navigation calls for marine animals as well as increased stress levels. Several studies in 2006 provided new evidence on the physiological and behavioral impacts of moderate noise from sources like boats and pile driving. These subtle impacts could accumulate over the long term to significantly disrupt populations, though more research is still needed on cumulative and population-level effects.