Gone fishing

There are more than 2,000 grizzlies living in this wilderness on the Alaska Peninsula and each adult can swell to more than 450 kilograms. That's a lot of weight for Katmai National Park to bear, especially when you add the nearly 40,000 humans who visited the Brooks River each year as it swells with countless salmon. Bears can be spotted fishing for their fill along the river in the summer and autumn, gorging on sockeye to fatten up for hibernation. Good news, you don't have to trek all the way to Alaska to observe them—you can get a great view of the feeding frenzy via webcam.