Technical advances to study effects of underwater noise exposure on hearing and behaviour of marine mammals
There is an increasing concern on how anthropogenic underwater noise affects marine mammals. Marine mammals, and especially cetaceans (whales and dolphins) rely on sound for all the daily activities (finding prey, communication, navigation, etc). Changes in behaviour, masking of their acoustic signals or hearing impairment due to noise exposure might have severe consequences. Since marine mammals spend the majority of the time underwater, it is challenging to study the effects of noise on them. Acoustic tags are used in our team to measure behavioural responses to noise exposure. Auditory brainstem responses can be measured to living marine mammals exposed to noise to determine the effects of acoustic deterrent devices on hearing. In addition, post-mortem examinations of the ears can also reveal potential effects of noise exposure (as well as from other causes) on hearing. Technical advances on living and death animals allow us to quantify effects of noise exposure on marine mammals.