|The whales really are in the shipping lanes AJP Photographs|
Surveys were conducted off the southern coast of Sri Lanka during February to April 2014 in order to investigate the distribution patterns of blue whales (Balaenoptera musculus) in relation to current shipping lanes and further offshore. There have been several reported ship strikes of blue whales in this area and the IWC Scientific Committee has recognised the potential for ship strikes to have population level impacts on blue whales in the northern Indian Ocean. A total of 1413km of visual survey effort was conducted on 16 survey days along north south transects between 5° 28’ N and 5° 53’ N. The highest densities of blue whales were observed in the current shipping lanes, peaking at an average of 0.12 individuals km-2 in the westbound shipping lane. These high densities of whales combined with one of the busiest shipping routes in the world suggest a severe risk of ship strikes. Previous data on blue whale distribution and coastal upwellings indicate consistent and predictable patterns of whale distribution, suggesting there is considerable potential for effective measures to keep ships and whales apart.