Sound judgement


The technology of acoustic tools to study sounds made or heard by marine animals has improved a lot over the last decade. Two new acoustic sensors—real-time and archival—are now being used to improve conservation efforts of the endangered North Atlantic right whales. Real-time sensors are deployed on surface buoys lowered onto oceans and archival sensors are affixed to bottom-moored buoys for long time periods. Marine mammals like whales, dolphins communicate, hunt and attract mates using sounds. Ships regularly pass over the hunting grounds of the endangered right whale. Noises from the vessels and naval sonar stress the animals to the extent they get stranded on shores and die. The blue whale once communicated across entire oceans.

Another study said it lost 90 per cent of its range over the last 40 years.


Down To Earth, January 2010