Research & Developments is a blog for brief updates that provide context for the flurry of news that impacts science and scientists today.
Yellowstone is among the United States’ most popular national parks, with more than 4.5 million visitors every year. So it’s probably no surprise that park staff does some picking up after visitors. What may be surprising, is that the staff recovered a record-setting 20,000+ pieces of trash, 5,600 rocks and sticks, and nearly 300 hats from the park’s hydrothermal areas this year, according to a USGS press release.
It’s no small feat to dislodge all of this trash from the park’s iconic hydrothermal features, and members of the park’s Geology Program are behind the effort. Much of it is done with shovels, grabber tools, but some efforts are more complicated, requiring fishing rods, strainers, slotted spoons, and grabber poles up to 30 feet long.
Most of this litter was left unintentionally, but serves as a good reminder for visitors to never throw anything into a hot spring or geyser, to hold on (or remove) their hats, and to stash their trash safely until they can get to a trash can.
Below is a list of some of the most notable finds of 2026.
- 36 pairs of sunglasses. All the better to see those geysers with, we suppose.
- More than 280 hats. Hats galore! Some had place names, like San Diego, Bears Ears National Monument, Miami, or Yellowstone itself. Sun hats and tie dye hats, patriotic hats and pawprint hats. A baseball cap with the words “COWBOY HAT” written on it. These accessories were likely blown off by wind, and park visitors did the right thing by leaving them behind and not venturing into the geothermal areas to rescue them.
- 54 camera lens caps. At least it wasn’t the cameras themselves? There did appear to be one children’s camera among the objects, though.
- A single jingle bell.
- Six Invisalign retainers! Oof, this one might have been more painful to lose than the 5 AirPods also found in the hydrothermal areas.
- $18 in coins, including Canadian dollars, euros, pesos, and yen. There were a few dollar bills as well. Most of these appear to have been thrown into hot springs or geysers on purpose, which is not allowed and will not make your wishes come true. If you want to throw your coins somewhere, throw them in a real wishing well, or to us here at Eos.
- Lots of Yellowstone paraphernalia. In addition to the hats, staff found six Yellowstone pressed pennies, 7 Polaroid photos (several of which were of the hydrothermal feature in which the photos were found), six Junior Ranger badges, and at least one Yellowstone pin. There’s something tragically poetic about this.
- A single Uno card (yellow 4).
- A tube of gouache paint (also yellow).
- Three fortune cookie fortunes: “You are the center of every group attention,” “Trust in the journey, for it is leading you to blessings,” and one that isn’t quite readable.
- 3 golf tees (there is not a golf course within the park).
—Emily Gardner (@emfurd.bsky.social), Deputy Editor
These updates are made possible through information from the scientific community. Do you have a story about science or scientists? Send us a tip at [email protected].
