September marks the start of narwhal migration season, but this fragile species is facing new challenges posed by global warming, commercial fishing, and seismic testing. Here Todd McLeish, author of Narhwals: Arctic Whales in a Melting World details some of the perilous new threats this endangered marine mammal faces in its annual move to warmer waters.
Mid-September is the beginning of migration season for nearly the entire population of 80,000 narwhals that spend the summer in the bays and fjords of the High Arctic islands of eastern Canada and the west coast of Greenland. After spending the ice-free months of July, August, and early September traveling in large groups, raising their calves, and eating next to nothing, they are beginning their slow journey to the southern end of Baffin Bay. They will be forced south for several hundred miles, keeping ahead of the southward expansion of sea ice until November when they reach what will be the edge of the winter ice pack, which typically extends across the Davis Strait from southern Baffin Island to the central coast of Greenland. There they will repeatedly dive to the seafloor — nearly a mile below — to feed on abundant fish and squid. The 30-minute round trip feeding forays aren’t without risks, as they must not only find food but also an opening in the ice cover to breathe while avoiding Greenland sharks in the water column and waiting polar bears at the surface. Continue reading