The narwhal habitat stretches from the Canadian High Arctic to Greenland, but occasionally some narwhals appear as far east as Svalbard Island off the coast of Norway. The Polar Science Center in Seattle estimates the narwhal population is around 80,000. This population is made up of subpopulation groups. A subpopulation group doesn't spend all year together but comes together during the summer period at the narwhals' summering grounds. Satellite tracking has identified some 10 subpopulations. Baffin and Somerset Island and northwest Greenland have the largest summering grounds, with up to 40,000 narwhals congregating there.