Yellowstone cutthroat trout are on the brink of extinction as invasive lake trout continue to eat them. With the park's ecosystem at risk, it's up to scientists to figure out where these predators came from and how to contain them.
Yellowstone National Park is home to a vast array of landscapes and a huge diversity of animals, united in a fascinating ecosystem, one that is currently in severe trouble. The area once contained over 19,000 elk, but its numbers have plummeted by 80% in the last two decades. The mysterious decline has sparked many questions, and researchers are in a race to provide answers. Join them as they investigate a series of theories and suspects, from wolves to bears to trees to trout, in an attempt to solve this alarming puzzle.
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