Safety

Off-road vehicles are prohibited in Yellowstone and most national parks. In spite of these restrictions, it is easy to get off-the-beaten track into the backcountry. My favorite is on foot… you'll quickly escape the crowds of the frontcountry a mere one or two miles off the loop road. The hike to Slough Creek in Tower country has breathtaking landscapes, lots of opportunities to see wildlife and great flyfishing. For more hikes, check out

 If you are eager to cover more ground and want to spend an extended period in the backcountry, consider taking a guided stock trip. Guided stock trips into the backcountry (on horse or llama) may be arranged with one of the stock outfitters licensed to operate in Yellowstone (see http://www.nps.gov/yell/planyourvisit/stockbusn.htm).

You may also bring private stock into the park. PLease note that overnight stock use is not permitted prior to July 1, due to range readiness and/or wet trail conditions. Horses are not allowed in frontcountry campgrounds, but are permitted in certain backcountry campsites.

For information on planning a backcountry trip with stock please see the online Backcountry trip planner (available at http://www.nps.gov/yell/planyourvisit/backcountrytripplanner.htm) or call the Backcountry Office at (307) 344-2160.

Unfortunately, the answer to this question is that there are numerous threats to the park and its Ecosystem, as well as to the infrastructure needs to maintain a safe and inviting place to visit.

The most basic threats that are always present seem to be: natural and non-natural fires, exotic/invasive plant and animal species, air pollution and the effects of climate change. 

The National Park Service has a well written article on the park ecosytem.  You follow the link here, (and below is a blurb from the article):

http://www.nps.gov/archive/yose/nature/nature.htm


"Threats to park resources and the integrity of park ecosystems include loss of natural fire regimes, air pollutants and air-borne contaminants, global climate change, direct impacts to resources from high visitation in some areas of the park, habitat fragmentation from both outside and inside park boundaries, and the invasion of non-native plant and animal species. The park is actively attempting to control the non-native plant species that pose the most serious threat, such as spotted knapweed, yellow star-thistle, bull thistle, and Himalayan blackberry. The presence of wild turkeys, white-tailed ptarmigan, bullfrogs, introduced fish and other non-native animal species in Yosemite threaten the park's native species."

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