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The park’s museum collection houses over 40 vehicles, both horse-drawn and motorized. Currently, the majority reside in off-site storage, and were recently treated under our cyclical cleaning program. Visitors are encouraged to come see two of our historic vehicles on display in the Heritage and Research Center; a 1974 Vespa Model 125 Primavera Scooter and a 1964 Cushman Model 765 Eagle Motor scooter.

In the early days of the park, people arrived by train and would ride up and through the park on stagecoaches. The crossover between horse-drawn vehicles and automobiles was short, as the horses would get spooked by vehicles. This safety concern led to a ban on horse-drawn vehicles in 1917. Motorized vehicles were welcomed, and allowed both employees and visitors to get around more difficult terrain or areas where horses and coaches couldn’t go.

Heritage & Research Center just north of the Roosevelt Arch at Yellowstone’s north entrance

Although they were used in the park earlier, it was around the 1950s that smaller vehicles such as motorcycles and scooters gained popularity. They were incredibly useful in traveling short distances quickly, like campground to campground or underdeveloped areas unfit for cars.

These scooters are on display at the Heritage and Research Center as part of the museum’s new in-person exhibit, Yellowstone National Park: Travel Through Time. Visitors are also welcome to explore the transportation exhibit virtually.

This exhibit was developed by Yellowstone National Park staff and made possible by the generous support of the Jane Lerner Fund of Yellowstone Forever, Yellowstone National Park’s official non-profit partner.

Yellowstone Forever supports various aspects of the Heritage & Research Center. With several million items, HRC has one of the largest collections in the National Park Service, housed within an archive, a library, and numerous museum collections. Find out how you can support and get involved at www.yellowstone.org/hrc. 

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Registration for Winter 2025-2026 Field Seminars is Now Open

Summer may almost be here, but it’s never too early to envision your ultimate cold-weather escape. When the summer crowds are gone and snow blankets the park, Yellowstone is transformed into a tranquil, glistening wonderland—an experience unlike any other. Winter 2025/2026 Field Seminar registration is now open! Join our expert field educators for an exclusive educational journey through Yellowstone’s quiet season. Explore hidden wonders, embrace the peaceful solitude, and deepen your understanding of the park’s extraordinary ecosystem.

Start planning your winter adventure today!

Registration for our 2025–2026 Field Seminars is now open—secure your spot today! Here are just a few of our courses to choose from:

• Yellowstone Wildlife: Winter Photography | December 11-14 | Justin Theurer
• Yellowstone’s Captivating Carnivores | December 15-18 | Wes Binder
• Call of the Wild: Decoding the Language of Wolves | January 24-28 | Amanda Evans &
Jeff Reed, Ph.D.
• Winter Yellowstone Naturalist | February 1-7 | Amanda Evans
• Tracking Yellowstone’s Winter Wildlife | February 13-17 | Luke & Sara Lamar, M.A.
• Adventure Skiing in Yellowstone – Crosscountry | February 18-22 | Jesse Logan, Ph.D. & Sam Archibald, M.E.M.
• Lamar Valley Wolf Weeks | February & March | Session 1, Session 2, Session 3, Session 4

The post Winter’s Magic Awaits in Yellowstone appeared first on Yellowstone Forever.

I am fortunate to experience this scene on a regular basis here in Gardiner, our town that sits on the edge of Yellowstone, right at the confluence of the Yellowstone and the Gardner rivers (The river and the town are named after the same person, but a southern drawl led to the additional ‘i’ in the town’s name). My significant other and I come to the river often. He is an excellent angler, but I have not quite learned to fly fish myself. I’d much rather find an aforementioned sit spot and observe the world around me. Spring is an exciting time when so many familiar sights return to Yellowstone. Among returning migratory birds and first blooms of long dormant plants, I especially appreciate the insect life around me. There can be so much biodiversity in a single spot if you look close enough!

I notice a few things right away. The first, unfortunately, is a mosquito, probably freshly emerged from its underwater nymph stage in a beaver-dammed section of the river a bit upstream. As pesky as these insects are, they play a vital role in the ecosystem. That, however, does not stop me from slapping away! I feel something on my leg and go to smack it, but this time I’m pleasantly surprised to find a caddisfly instead of a mosquito. I tell my partner about this observation, he stops to change his fly, and lands a trout on the next cast! The art of fly fishing has to include the science of entomology, and a good angler will pay attention to what’s emerging and flying around. That’s fish food!

There are several types of insects that begin life in a freshwater habitat. Some examples include mayflies (Ephemeroptera), dragonflies and damselflies (Odonata), stoneflies (Plecotera), and of course caddisflies (Trichoptera). All of the above start as an egg, then hatch into their immature stage, known as ‘nymphs.’ These insects, plus several other aquatic species, are good indicators of a healthy waterway.

Mayflies are the only insect to have a winged immature stage. Entomologists call that the ‘subimago’ phase, and anglers know them as ‘duns.’ The final molt brings them to the sexually mature ‘imago’ phase, or ‘spinners’ to anglers. These adults only live a few hours to a few days, hence the ephemeral nature of their order name (Ephemeroptera).

The nymphs of the Odonata order are also worth mentioning. These prehistoric creatures breathe through their butts and are predatory from the day they hatch. Their mouth part (known as the labium) is retractable, and they punch it out to snatch other insect nymphs and even small fish and tadpoles. Imagine a miniature and aquatic version of the terrifying xenomorph from Alien.

Stoneflies are another angler favorite, specifically the famous Salmon fly. These gentle giants (relatively speaking) can grow up to 3 inches long and have only vestigial mouthparts as adults. They do all their eating in the nymph stage, and so once they emerge from the water, they mainly focus on adult activities (mating). I look forward to seeing these monsters in a couple weeks.

Last but certainly not least, are the caddisflies. These are remarkable insects, and their underwater life is beautiful. They create protective cases to live in, and use whatever materials are available to them, including small rocks, twigs, grass, and even an occasional snail shell! From my sit spot, I can see a few larger caddisfly nymphs scooting along the bottom of the eddy, and I hear a big splash downstream. Another fish on the line! Not only are these aquatic insects a favorite food for trout, but they also provide an important food source for many other riparian species like bats, dragonflies, birds, spiders and more. I was happy to see some caddis this past weekend, for the famous ‘Mother’s Day Hatch,’ even though we didn’t have the clearest water for fishing. Some years there are so many caddisflies in the air that it almost seems as if it is raining insects!

As the days warm up, I anticipate more river time in my future appreciating the life teeming above and below the waterline. Even if most people don’t appreciate the ‘bugs’ like I do, they are still an important part of our ecosystem, not only as a food source but also for the role they play in decomposition and nutrient cycling. The presence of these insects indicates a healthy body of water, as many are sensitive to pollution, and don’t necessarily have the means to migrate to cleaner waters. Thankfully here in Yellowstone we have pristine waterways and lots of critters to find. The Yellowstone Forever Institute educators especially enjoy taking students to participate in stream ecology activities. In addition to collecting samples from a stream and recording the number of species present, we also measure the water’s temperature, pH, and flow rate. After all critters are safely deposited back into the water, this data is saved to Yellowstone Forever’s phenology log. By understanding and protecting these small yet significant creatures, we can ensure the sustainability and resilience of Yellowstone’s wetlands for future generations.

by Katy Fast, Yellowstone Forever Institute 

Photos Top to Bottom:

Yellowstone River at sunset, NPS / Jacob W. Frank
Caddisfly, NPS / Jacob W. Frank
Damselfly larvae, NPS / Jacob W. Frank

The post Naturalist Notes: Life at the Waterline appeared first on Yellowstone Forever.

As the snow recedes and the days lengthen, Yellowstone’s high-altitude ecosystem undergoes a remarkable transformation. Unlike in lower elevations, where spring unfolds in predictable waves, Yellowstone’s flora emerges in microclimates dictated by elevation, snowpack, and geothermal activity. This unique interplay means that while valleys burst with blooms, some high-elevation plateaus remain locked in winter for weeks longer.

Among the first flowers to appear are steer’s head (Dicentra uniflora), a species so specialized that it depends on underground fungi to access nutrients. This rare adaptation allows it to thrive in Yellowstone’s nutrient-poor soils. Yellowbells (Fritillaria pudica) are another early bloomer, emerging near warm south-facing slopes. These delicate flowers rely on temperature-sensitive germination cues, a critical trait for surviving the unpredictable mountain climate.

One of the most fascinating early bloomers is the pasqueflower (Anemone patens). Coated in fine, silvery hairs, it insulates itself against freezing temperatures, enabling it to bloom even as snow lingers nearby. Unlike many plants that rely solely on insects for pollination, pasqueflowers can also self-pollinate, ensuring survival in years when early pollinators are scarce.

Yellowstone’s geothermal areas also create floral anomalies. In thermally influenced ground, plants such as springbeauties (Claytonia lanceolata) may bloom weeks ahead of their counterparts just a few yards away, an adaptation that showcases how species have evolved to exploit even the smallest environmental advantages.

For those eager to explore these adaptations firsthand, the Yellowstone Forever Institute offers guided field experiences where field educators dive deep into the science of Yellowstone’s flora.

Programs, like our Private Tours, provide an unparalleled opportunity to see, touch, and understand the intricate relationships that define one of the world’s most unique botanical landscapes.

Photos:

Feature: Pasqueflower, NPS / Jacob W. Frank
Yellowbells, NPS / Jacob W. Frank
Springbeauties. NPS / Jacob W. Frank

The post Yellowstone in Bloom appeared first on Yellowstone Forever.

In Yellowstone, the sage steppe supports some of the first signs of new life including the nesting birds of spring. As life returns to the limbs of the sagebrush a nursery takes shape. The newly revived Sagebrush, also known as Artemisia tridentata, a member of the Asteraceae family, will support a variety of songbirds in their pursuit of bringing forth the next generation. The sagebrush provides shelter as well as a cornucopia of insects, and nesting material. However, some birds prefer a scrubbier bush known as rabbitbrush. Equally as important to the sage steppe nesters. Rabbitbrush, also known as Ericameria nauseosa– part of the Asteraceae family, provides habitat for bird species that nest on the ground. As snow melts away the first birds in the ecosystem chose the dry sagebrush canopies for their nursery’s.

The Brewer’s sparrow is a common early arrival on the landscape that seeks out sagebrush. The Brewer’s sparrow arrives in the ecosystem in April and May looking for sagebrush and territory that will support new broods. Learn more about this bird and its unique nesting choices. The Brewers sparrow males start erupting in song shortly after their arrival as they defend new nesting territory and mates. The complex song of the Brewer’s sparrow can be heard into late July, but once chicks have successfully fledged those songs will taper off.  Through careful selection the Brewer’s sparrow chooses which sagebrush will support their nests as that can determine their success and hopes of bringing forth the next generation… Brewer’s sparrows tuck their nests against the trunk of a sagebrush, no more than about four inches off the ground, trying to conceal its precious blue-green and brown speckled eggs. Often in one clutch a Brewer’s sparrow will have between 3-5 eggs and may have as many as two clutches in one season. As the adult Brewer’s sparrow pair waits for the arrival of chicks, they will try to trick potential predators leading them away from their nest as they flush away low to the ground. Sometimes when flushing off the nest they will pretend to have a broken wing to be more enticing for predators, so they don’t pursue the nest. Between eleven and thirteen days of incubation will pass before the first hatchlings emerge, it’s a time of anticipation and hope. The springtime nests of songbirds, such as the Brewer’s sparrow, act as a symbol for new beginnings brought with the changing of the seasons.

Spring is often characterized as a season of optimism and growth; in Yellowstone this is evident with the welcoming of new birds like the Brewers Sparrow. The beginning of spring foreshadows the summer season to come, with the influx of new life into the ecosystem Yellowstone comes alive after a long period of dormancy. As you visit this remarkable ecosystem, don’t forget to keep an eye out for species like the Brewer Sparrow that are often overlooked as harkening in the changing seasons.

Article and nest images by Abbey Thomas, YF Field Educator
Featured image: USFWS, Tom Koerner

The post New Beginnings appeared first on Yellowstone Forever.

Yellowstone in winter is a land of transformation. Snow blankets the valleys, steam rises from thermal features, and on the coldest mornings, trees, grasses, and even bison wear a glistening coat of frost. These icy formations, delicate yet fleeting, turn the park into an ephemeral sculpture garden. But look closely, and you will see that not all frost is the same.

Two of the most fascinating types of frost found in Yellowstone—hoar frost and rime ice—appear similar at first glance but form under entirely different conditions. Understanding them is more than just a science lesson; it is a glimpse into the dynamic interplay of temperature, moisture, and time—a reminder that even the smallest details of nature are shaped by precise conditions.

Hoar Frost

Hoar frost is winter’s most delicate and intricate ice formation. It forms when water vapor in the air undergoes sublimation, meaning it transforms directly from gas to solid without passing through a liquid phase. This occurs on clear, calm nights when air moisture levels are high and surfaces—blades of grass, tree branches, even fur—become colder than the surrounding air due to radiative cooling. As heat escapes from these surfaces into the open night sky, they drop below the dew point—the temperature at which moisture in the air condenses. However, instead of forming liquid dew, the moisture freezes immediately, creating ice crystals that attach and expand outward in intricate patterns.

Because there is no wind or external force shaping it, hoar frost grows freely, following the natural laws of crystallization. Its structure is influenced by temperature and humidity, forming feathery, hexagonal ice structures that resemble frost flowers or lace. The colder and more humid the air, the larger and more delicate the frost patterns become. But this beauty is fleeting—hoar frost is highly sensitive to changes in temperature and wind. A single gust of wind can shatter the fragile formations, and as soon as the sun rises, the warming air causes the ice to sublimate back into vapor, leaving little evidence of its existence.

Rime Ice

Where hoar frost thrives in calm conditions, rime ice is forged in movement. Rime ice forms when supercooled water droplets—tiny liquid particles that remain unfrozen even in sub-freezing temperatures—encounter a solid surface and freeze on impact. These droplets exist in clouds or fog when the air temperature is below freezing, but because they lack a nucleation site (a surface to begin forming ice crystals), they remain liquid until they touch something solid. The moment they collide with a tree branch, a rock, or even a bison’s fur, they flash-freeze, forming an opaque, rough-textured ice.

Unlike hoar frost, which develops in delicate crystalline patterns, rime ice is depositional, meaning it builds up gradually as new supercooled droplets continue to hit the same surface and freeze. The direction and intensity of the wind influences its formation, sculpting thick layers of ice into wind-swept ridges, jagged clusters, or smooth coatings.

You will often find rime ice in Yellowstone’s geothermal areas, where warm steam rises into frigid air and instantly freezes onto surrounding surfaces, coating boardwalk railings and trees in ghostly white formations. It is also common at higher elevations, where freezing fog—dense with supercooled droplets—blankets exposed ridges and creates windward-facing ice accumulations. The denser the freezing fog and the stronger the wind, the thicker the rime ice becomes, sometimes forming dramatic spiky formations that seem to stretch in the direction of the wind itself. Unlike hoar frost, which vanishes quickly in sunlight, rime ice is more durable, often lasting for days or weeks unless a warm front melts it away.

Where to See These Frosty Formations in Yellowstone

Yellowstone provides the perfect conditions for both hoar frost and rime ice, and each can be found in different places across the park.

• Hoar frost is most seen on cold, clear mornings in meadows, along riverbanks, and even on the fur of bison, turning them into ghostly white silhouettes.
• Rime ice thrives in geothermal areas where warm steam freezes instantly upon contact, often found coating trees and boardwalks in places like Mammoth Hot Springs or Norris Geyser Basin. It also appears on exposed ridges where freezing fog and wind create thick, icy layers on vegetation.

At their core, hoar frost and rime ice are a study in contrasts—one is delicate and fleeting, the other wind-forged and resilient. Hoar frost forms in perfect calm, while rime ice is born of movement and collision. One builds intricate lattices that vanish with the first touch of warmth; the other layers itself into thick, wind-carved ridges that linger long into the cold. Yet both are reminders of how nature works in balance, shaping the landscape through the quietest and most powerful forces. Their existence depends not on chance, but on a precise alignment of temperature, humidity, and time. They tell a story of Yellowstone in winter—not just of ice and cold, but of the conditions that shape the wild in ways both visible and unseen.

These frost formations may be temporary, but their beauty lies in their fleeting nature. Like a snowflake that lands on your glove, they are winter’s artistry at its most intricate—reminders that even in the harshest cold, nature finds a way to create something delicate, something fleeting, and something worth noticing.

So, next time you find yourself in Yellowstone on a frigid morning, take a moment to look beyond the obvious winter wonderland. The frost tells a story—one written in ice, shaped by wind, and fleeting as the morning sun.

Images:

Feature: Rime ice on the boardwalk of Mammoth Hot Springs Upper Terraces, YF / Matt Ludin
Top to bottom:
Hoar frost built up on grasses under standing dead lodgepole pine trees on Tangled Creek. NPS / Jacob W. Frank
Rime ice on trees on top of Palette Spring at Mammoth Hot Springs, YF / Matt Ludin
Hoar frost on cottonwood trees in Lamar Valley at -20 below zero F. YF / Matt Ludin
Bison covered in hoar frost near Old Faithful. YF / Matt Ludin

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