A pine marten in the Cairngorms National Park, Scotland

© SCOTLAND: The Big Picture/Minden Picture

Playing hide-and-seek in the Cairngorms

Ready or not, here we come! There are plenty of hiding places here in the Cairngorms National Park in the heart of the Scottish Highlands. At 1,748 square miles, it’s the biggest national park in the UK and home to an abundance of wildlife, including the European pine marten, a cat-sized member of the weasel family. The elusive creatures prefer woodland habitats and are adept climbers, spending much of their time in trees, where they can leap over 10 feet between branches in pursuit of squirrels. According to research, pine martens are reducing the population of invasive grey squirrels in Scotland, which is good news for the UK's beleaguered reds, who actually benefit from exposure to their natural predators. The enemy of my enemy is my friend.