What does it take to keep Colorado’s native amphibians healthy? From dodging lightning in the backcountry to being pulled out of waist-deep mud, or slowly backing away from a group of territorial beavers and tent camping above treeline –– it’s a job filled with outdoor adventures.
For this dynamic duo of amphibian technicians at Colorado Parks and Wildlife (CPW), when they say no two days are the same, they mean it.
In a world where every puddle holds a possibility, and every wetland is a wonderland –– CPW staff dare to venture where few have gone before to study native amphibian species and their habitats.
Amphibians (including frogs, toads and salamanders) can be indicators of ecosystem health and are highly susceptible to disease, drought and pollution –– which is why CPW has a dedicated crew working to conserve them.
Get a behind-the-scenes look at the exciting escapades and unpredictable challenges that arise when working in Colorado’s rugged terrain.
Because in the world of amphibian conservation, the smallest creatures can make the biggest difference.
Written and photos taken by: Statewide Aquatic Amphibian Technicians Isabella (Iz) Butzer and Lindsey Hughes
How We Got Here
Hi, I’m Isabella (Iz)! I began working with amphibians in high school while volunteering at the Oklahoma City Zoo’s herpetarium. Then, I made my way to Colorado State University to complete my Bachelor of Science degree in Fish, Wildlife, and Conservation Biology, where I assisted with aquatic ecology fieldwork and research at a university lab. After that, I worked on CPW’s reclamation crew to conserve greenback cutthroat trout, and then returned to my passion for amphibian conservation and joined the amphibian crew this year.
Hi, I’m Lindsey! I first became interested in amphibians and reptiles as a hobby (also known as “herping”) while serving as a salamander crossing guard during my studies at the University of Vermont, where I got my Bachelor of Science degree in Fish, Wildlife, and Conservation Biology. I studied abroad in Botswana, where I worked with local communities to research the preservation of indigenous languages and knowledge, as well as African mammal and bird populations. I had the opportunity to volunteer at the Vermont State Fish Hatchery during my undergraduate studies. I started pursuing my passion for working with amphibians last year on CPW’s amphibian crew and have loved being on it ever since.
A Day in the Field
A typical Monday morning for us starts around 6 a.m. when we meet at the shop to pack for our week of boreal toad and wood frog surveys. On one survey day, we packed our camping gear, waders, nets, data sheets, scales, rulers and frog bags (mesh bags for holding frogs while collecting data) and then headed to the mountains east of Walden, Colorado. We arrived at our first site around 10 a.m., with the sky darkening and a soft, thundering rumble of quaking aspens. Our goal: find boreal toads.
Honing our bushwhacking skills, we pushed through willows, tall grass and downed trees as we reached the site identified by the Northeast Region Native Aquatic Species Biologist and the state Amphibian Coordinator. We spent about an hour walking around the ponds of a historic beaver complex looking for small, hopping movements that toads make when humans come near. Because it was a chilly day, the toads were slow-moving and easy to catch by hand (with a gloved hand to protect their skin from diseases and the oils on human hands).
After we caught the toads for the day, the rain rolled in. We hunkered down and processed them all –– collecting valuable data about their health. We recorded their length and weight to understand population demographics, identified their sex to better understand the reproductive capacity of the population, and swabbed them to determine whether they had chytrid fungus. We also took a picture of their stomach to capture the unique pattern on each toad’s skin, which works like a fingerprint to identify an individual toad.
We survey for various reasons, including keeping tabs on historic breeding sites, checking whether boreal toads are present where they have been known to live, and testing whether the toads there have diseases, including chytrid fungus (Batrachochytrium dendrobatidis, or Bd). The spread of chytrid fungus — a deadly skin disease targeting amphibians — into Colorado has led to declines in boreal toad populations. CPW’s consistent monitoring is done to understand how populations are affected by chytrid fungus and how the pathogen is spreading throughout the state.
One way to protect this species is to not put all our eggs in one basket, or pond, in this case. The more isolated toad populations we have, the better. That way, if the fungus hits one population and causes a decline, other populations have a buffer.
With all the toads processed and a soaking wet data sheet, we started back for the truck in the pouring rain and startling lightning. We decided to run back to the truck to limit our exposure to the lightning, catching wafts of moose beds and stepping next to mountain lion prints left in the mud, likely made just a few hours earlier. Absolutely soaking wet, we hopped into the truck, wrung our sweatshirts out the window, and turned on the heat and radio. Our next destination was already on our minds: surveying for wood frogs.
Wood frogs are little brown frogs that reside in a small pocket of the mountains of northern Colorado. Due to a lack of recent information about the species, wood frogs are listed as a Species of Greatest Information Need in the State Wildlife Action Plan (SWAP). They are a cryptic species that live in complex habitats that are difficult to access. Wood frogs are found in high-elevation ponds and meadows, which are typically only accessible on foot, often requiring off-trail navigation over and around dense vegetation and downed trees. They also often breed early in the year, when there is typically snow on the ground.
We’ve recently been working to learn about this understudied and overlooked frog. For the past two years, we have been gathering information on their current distribution, the prevalence of chytrid fungus in wood frog populations, and their genetic diversity. This year, funding was received to begin a full occupancy study on wood frogs. Gathering this missing information will help amphibian managers and researchers determine the conservation actions necessary for this species and inform future investigations.
Our next site was a pond a few miles off the dirt road. As we hiked in, still damp from our morning survey, we had a good feeling about finding wood frogs because, as we like to joke, “the harder it is to get to a site, the more likely you are to see wood frogs.”
After surveying for several hours, we found a wood frog buried in the mud along the banks of a small pond and processed it, taking measurements similar to those of the boreal toads. We were ecstatic upon seeing this wood frog because it was the first one seen in the area in 34 years!
On a wood frog survey earlier in the summer, we had just reached our last spot to search as the sun began to set. We began walking around the lake with our nets and then froze after hearing a super loud “BOOM” sound. We looked up to see a family of beavers cannonballing off their lodge into the water. This is very unusual behavior because they can swim under the lodge to exit.
Each beaver landed with a huge splash and began swimming in our direction. As they swam around us, they smacked their tails against the water to make loud noises to scare us off. We slowly backed up to give them space in the lake and watch these typically nocturnal creatures from afar. As we backed away, they calmed down, and we could see them swimming peacefully in the water. We smiled and laughed about having to run away from beavers and noted on the datasheet that we could not survey due to “angry beavers.”
We then headed to our campsite for the night, set up camp, made dinner, and joked around as the temperatures dropped and the stars came out — getting ready to do it all again tomorrow.
More Than Just a Day Outdoors: Conservation in Action
Earlier in the season, we drove all around the state to catch boreal toads laying their eggs in small ponds in the mountains in early summer. We took small sections of their jelly bean-like egg strands and carefully placed them in small coolers for transport to CPW hatcheries. This year, because of the record low snowpack, the toads started laying their eggs one month earlier than in typical years, adding an unexpected surprise to the start of toad season.
2. Tadpoles in the Bellevue Watson Research Hatchery.
3. Tadpoles being released into their new home.
In July and August, we begin stocking the tadpoles we brought into the hatcheries as eggs into areas within their historical range to establish new populations. During this part of the season, we drove to the Fish Research Hatchery in Bellvue, Colorado, and the Native Aquatic Species Restoration Facility in Alamosa, Colorado, to pick up large bags of tadpoles. We would then hop back in the truck and drive up into the mountains to meet a team to take the tadpoles to their new home, either by backpacking them in or by taking them up in a UTV
This translocation process, in which we stock both wild-sourced and captive-bred tadpoles into suitable habitat, allows us to increase the number of boreal toads rangewide. Currently, this is the primary conservation strategy for offsetting chytrid-related population declines.
Additionally, in the peak of the summer, we survey for northern leopard frogs, a species of highest conservation priority in Colorado. To better conserve this species, we need to understand it better. Knowing more about their genetic diversity, distribution and connections between populations is critical for protecting this rare amphibian. We are collaborating with a PhD student at Colorado State University to gather this information to inform future conservation efforts, such as translocations. To collect this information, we are surveying for northern leopard frogs at sites with and without known populations to improve understanding of the species’ range in Colorado. We also take genetic samples, allowing us to better understand genetic diversity within the state’s population.
Wildlife Worth Protecting: The Work Continues
Amphibians are the most at-risk vertebrate group on Earth, and their persistence is critical to insect control, food web balance and biodiversity worldwide. In Colorado, all amphibians are threatened by pollution and toxic chemicals, habitat loss, road mortality, changes in water management, invasive species and disease. CPW identified six amphibian species as Species of Greatest Conservation Need in the State Wildlife Action Plan, which identifies species and habitats that are the highest priority for conservation. Through this work, CPW amphibian biologists ensure Colorado has resilient ecosystems, a priority in the 2026-2036 Strategic Plan, which sets overarching goals and actions that guide CPW’s work.
We have a unique opportunity to contribute to their conservation and help these often underappreciated species persist and adapt to a changing environment.
Regardless of the unpredictable weather, challenging terrain, long days in the mud — and the challenge of trying to find some elusive amphibians that have mastered the game of hide-and-seek — we love it. We get to study and protect some of Colorado’s most remarkable creatures. Every data point we collect counts. Every tiny tadpole we release can have a big impact on the future of our ecosystems.
Camera Roll of an Amphibian Technician
