People living in the Arctic settlement of Ny-Ålesund, Norway, have been dealing with a nontraditional pest this summer: polar bears. Residents of the northernmost permanent human settlement, many of them scientists, have called the increasing presence of polar bears near the town's research center a "nightmare." They have reduced access to certain areas and forced locals to learn to shoot, Agence France-Presse reported.

"As [much] as possible, we travel in pairs," Dutch ornithologist Maarten Loonen said, adding that he's seen the polar bear population in Ny-Ålesund grow over his past 20 years of living there. "I tell my students, 'The polar bear views you as potential prey.'"

There are about 25,000 polar bears worldwide. They mostly live in Canada, but a sizable community has developed in Norway over the years, where the archipelago Svalbard banned polar bear hunting in 1973. The area's polar bear numbers now hover between 1,900 and 3,600, according to the Norwegian Polar Institute. They've become more active in urbanized areas as global warming has diminished their icy habitats.

Polar bears don't regularly attack humans, and nobody in Ny-Ålesund has ever been hurt by one. But the residents constantly see the 1,200-pound animals roaming around, looking for food. The top TripAdvisor review of the city is titled "Watch out for polar bears!" 

To be prepared, scientists who work out in the field in Ny-Ålesund are required to carry a radio and rifle at all times. Tourists who come to visit are permitted to walk on nature trails but can't go far without polar bear guards. "Always be vigilant. Bears could be anywhere, and they are unpredictable," logistics adviser Sebastien Barrault told AFP. "A gun is your passport for leaving the town."

Ny-Ålesund isn't the only area having trouble with polar bears. During peak bear season last October, the Canadian town of Arviat banned children from trick-or-treating outdoors on Halloween because of the animals. At the time, Arviat's polar bear monitor was seeing about eight a day, Slate reported.