On 19 May 2022, Joan and I had our first full day in Yellowstone National Park (YNP).  This two-part blog covers what we did in the morning: an excursion to the Mammoth Hot Springs, only 5 miles from the Gardiner/Roosevelt Arch entrance. Shortly after passing through the gate, we caught sight of a river running alongside the road. We had no idea that within 20 days, this river would rise and take out part of the road on which we traveled! The recovery effort has also been phenomenal and the National Park Service has done a great job opening up the park again.

About 10 minutes into the park, Joan called out that she had seen a bear! She pointed to my side of the road and, looking up, I saw the bear on a hillside beside some rocks — she was enormous (perhaps the biggest we saw). She was also accompanied by offspring so I began scrambling to get my camera. By the time we got to a pull-off, they had disappeared behind big boulders and did not reappear. She looked somewhat like the (blurry) bear below that we saw another day when we couldn’t stop (rangers were present and moved everyone along). This spotting was certainly an exciting beginning to our YNP adventure.

This sighting taught me that Joan would be an excellent wildlife spotter even when guiding the car along winding roads with sometimes steep drop-offs at the side! It was cold our first day and we dressed warmly – long pants, sturdy shoes, sweaters, warm jackets and caps.

I was glad that we didn’t have to gallivant around in the long dresses and headgear worn by the first women who visited the park. However, the early female visitors to YNP were no “delicate flowers” as I learned from a book of their writings (Sidesaddles and Geysers: Women’s Adventures in Old Yellowstone. 1874 to 1903. Edited by M. Mark Miller).

Carrie Strayhorn wrote, after her 1882 visit to YNP, that both men and women clambered all over the mineral deposits. She and her party traveled about 400 miles on horseback through the park, leaving her with memories of “the charms of nature which go with the wilderness and wonders in all their primal glory.” Strayhorn visited Mammoth Hot Springs and we made that our first stop. (Photo from “Fifteen Thousand Miles by Stage (1911) by Carrie Adell Strahorn)

At the entrance to the Mammoth site, we were met by brown-headed cowbirds (which we have in North Carolina) and black-billed magpies (Pica hudsonia).

The first thermal feature we neared is called the Hymen Terrace. Old records kept at the University of Wyoming Libraries contained an enthusiastic description of this site.

As our day had started off quite overcast, this thermal did not look very colorful or terribly fascinating, so we moved on to walk along the trail.

Off to the side was a structure of some 37 feet in height (11 m) known as the Liberty Cap.

It received this name in 1871 from people who thought it resembled the caps worn by French revolutionaries who fought for freedom and liberty. It looked a bit more interesting when the skies cleared and the sun appeared.

The Mammoth site’s thermals mainly include hot springs and travertine terraces. Joan generally walks much faster than me and I stop often to photograph, so we split up to see the sights.

As Joan took off down a boardwalk, I stopped to photograph my first view of a Clark’s nutcracker (Nucifraga columbiana). I hadn’t expected to see many birds around the thermals so it was a welcome surprise.

Hot springs are Yellowstone’s most common thermal features. They comprise pools, sometimes quite deep, of heated water that may be calm and clear or froth like boiling water.

Rain and snow bring water that seeps into the earth where it is heated. It is still not certain which volcanic heat source is responsible for this.

It might be the magma chamber underlying the Yellowstone Caldera or another smaller place nearby. According to researchers, only 10% of the water in the Mammoth area is above ground at any one time.

What looks like steam arises from the hot springs and this seemed to be especially the case when we were viewing them in colder temperatures. Here you can see how our view of the Palette Spring changed as the day started warming up.

Read on to find out what causes the colors in the hot springs!