Scientists studying endangered southern resident orcas have noticed a steady increase of mysterious gray patches and gray targets (circular lesions which may appear on concentric rings – ed.) on the whales’ skin from 2004 to 2016.
To date, researchers managed to identify six distinct types of lesions, with the two most common types being gray patches or targets. Some resemble tattooed skin.
They do not know the cause of the lesions and are worried that they could be due to underlying health problems in the struggling population.