We've been warned for years that global warming could change the face of Yellowstone National Park, and the prediction has already come true when it comes to grizzlies. Now, however, we have an entire species threatened by the changing climate: the pika.

President Barack Obama and his family will be visiting Yellowstone National Park on Aug. 15 after a visit to Bozeman as part of his summer vacation.

Low gas prices and the affordability of a trip to Yellowstone National Park fueled a record-setting month in American's oldest national park -- by a huge margin. Over 900,000 people entered Yellowstone in July; up 11.4 percent from the same month in 2008, and up over the previous all time record of 847,000 visitors set in July 1995.