Study: Harbour porpoise react to high frequency vessel noise

Harbour porpoise surfaces off Whytecliff Park

A study recently published in Nature suggests that harbour porpoise react to high-frequency noise generated by vessels. In 27.5% of cases, the animals exposed to recorded vessel noise responded with what appeared to be avoidance behaviour.
Harbour porpoise inhabit shallow coastal waters where they are frequently exposed to vessel noise. While the effects of high-frequency noise have so far been largely overlooked, the authors conclude that vessel noise may indeed be a substantial source of disturbance for these small cetaceans.


Report: Vaquita population continues to decline, faster than expected

A report published recently by the Committee for the Recovery of the Vaquita (CIRVA) points towards the decline of vaquita at a much higher rate than previously estimated. A review of acoustic monitoring data gathered between 2011 and 2014 shows an average estimated annual rate of decline of 31%, compared to the 18.5% annual decline estimated for the 2011 to 2013 sampling period. The higher average is the result of a very low number of vaquita detections in 2014.