Yellowstone National Park does not exist in an environmental vacuum.  In many ways, it is an island surrounded by environmental issues that threaten the very resources the park is meant to protect.
One of the most impressive things I have observed is how the park can change within a relatively short amount of time.  Some changes are conservatory: the restoration of wolves and an increase in the grizzly bear population.  Others are not: the invasion of exotic species, unconstrained human second home and industrial development, and the steady increase in tourism.  Many people feel we are very much “loving our National Parks to death.”  But there is hope.  You can inform yourself and make knowledgeable choices.
Watch the video I narrate below about the interplay between the Yellowstone cutthroat and exotics in the park.