Yellowstone National Park, Continental Divide

Many CDT thru-hikers consider the walk through the unique and gorgeous Yellowstone National Park to be the highlight of the entire journey. Yellowstone was the world’s first National Park, with the area designated a federally protected wilderness by Congress in 1878 under the administration of President Ulysses S. Grant. The documentary filmmaker Ken Burns called the U.S.’s system of National Parks ‘America’s best idea’, and the concept of a nationally protected park has now been exported worldwide. Whether you’re up a fell in the Lake District in England, watching puma in Torres Del Paine in Chile, roaming the Serengeti in Kenya, or exploring the steamy jungles of Khao Sok in Thailand, the idea for protecting areas of deep natural and cultural heritage, and having them freely accessible by the public originates here, in Yellowstone.

Yellowstone National Park occupies the Yellowstone Caldera. It sits on top of this dormant supervolcano, which is the source of all the strange geothermal activity here - the fountains of the geysers, the hot springs and the geothermal pools. Most famous is the huge geyser, Old Faithful, named so for the regularity of its eruptions (about every 90 minutes). There are also the candy-coloured geothermal pools, their bright hues created by thermophilic bacteria that make the scalding hot volcanic water their home.

Yellowstone is also one of the most biodiverse places on our planet and the largest, nearly intact ecosystem in the world’s northern temperate zone. Much of this incredible natural wealth stems from the reintroduction of wolves to the park in 1995. As a cornerstone species, wolves are essential for maintaining balance in the ecosystem. Their reintroduction triggered a phenomenon known as a ‘trophic cascade’, which is when changes to one part of the ecosystem snowball, triggering wide-ranging changes in the rest. 

After the wolves in Yellowstone disappeared, the elk population exploded. As their numbers grew, they began to weigh too heavily on the ecosystem’s resources, and they became less wary of predators. They moved about less and lingered in relatively small areas, overgrazing them. This led to the destruction of young willow, aspen and cottonwood trees, and as tree numbers plummeted, so did the bird and beaver populations, who relied on the woods. With the beavers gone, their dams disappeared, and with them, the wetlands that the dams preserved, affecting thousands of species. Elk overgrazing also changed the course of the rivers, as there was less root structure to hold the soil on the banks, leading to huge die-offs of fish and amphibians. 

The problem was solved with this bold rewilding scheme. The 10 packs of wolves (about 124 individuals) that thrive here now have thinned out the elk herds. In turn, the aspens have regrown, the beavers are back, the wetlands have been restored, and the river erosion has slowed. The story is truly inspiring and shows how, with a careful appreciation of the balance of our natural world (and proper funding for conservation bodies), some of the damage we humans have done to our environment can be reversed or, at least, mitigated.

Thanks in no small part to the hard work of conservationists, my trip through Yellowstone was a veritable safari. Have a look at the Yellowstone Wildlife local spot to see what I saw!