Why an Alaska island is using peanut butter and black lights to find a rat that might not exist

On an island of windswept tundra in the Bering Sea, hundreds of miles from mainland Alaska, a resident sitting outside their home saw — well, did they see it? The purported sighting would not have gotten attention in many places around the world, but it caused a stir on St. Paul Island, which is part of the Pribilof Islands, a birding haven sometimes called the “Galapagos of the north” for its diversity of life.