Skin disease in orcas off North American coast concerns scientists

Lesions found on 99% of southern resident orcas studied on Pacific north-west coast

Scientists studying an endangered population of orcas resident off the Pacific north-west coast of Canada and the US have recorded a “strong increase” in skin lesions on the animals’ bodies, which they believe is due to the decreasing ability of their immune systems to deal with disease.

The lesions appear on the whales as grey patches or targets, or black pin points. Some resemble tattooed skin. Their presence on the animals’ graphically black and white bodies is “increasing dramatically”, according to Dr Joseph K Gaydos of the SeaDoc Society at the school of veterinary medicine at the University of California, lead author of the scientific paper.