In June 2017, three critically endangered North Atlantic right whale carcasses were spotted floating in the Gulf of St. Lawrence. In the weeks that followed the number of dead right whales rose to 10, while three more were found entangled alive in fishing gear. (The total number of deaths may be as high as 12.)For a species with approximately 500 surviving animals in the world, this was a crisis — an unprecedented die-off signalling a troubled outlook for the species.