By Zaylah Pearson-Good.
Due to a history of hunting and habitat loss, beaver colonies have diminished across the San Luis Valley in the last few centuries. Though beaver populations are stable in parts of the Valley, efforts are underway to restore the species to key waterways that they once occupied. Beavers play a major role in maintaining ecological balance, protecting endangered fish and mitigating the impacts of wildfire.
It takes a beaver approximately 24 hours to completely re-engineer an ecosystem. These stout, orange-toothed rodents use sticks, mud, leaves and grasses to build watertight dams that slow and redirect water across a landscape, creating lush wetland habitats. Their dams assist in water purification, groundwater recharge, enhance the capacity of soil to sequester carbon and hydrate the surrounding land, making it more drought resilient. Beaver dams also create habitat for insects, fish, birds, small animals and vegetation, increasing ecosystem biodiversity and productivity.
Beavers play a critical role in mitigating the impacts of wildfire as well. Peter May, a 30-plus year firefighter and Crestone resident, believes that supporting local beaver colonies is key to protecting parts of the SLV against wildfires. “Beavers are water stewards; they rehydrate the forests…We need them so that when a wildfire does occur here, it can tend to be more limited as the landscape becomes more hydrated,” explained May.
May’s stance on beavers is echoed by a mounting body of scientific research. In a 2020 study of wildfires across the Western USA, including Colorado, ecohydrologists Dr. Emily Fairfax and Andrew Whittle found that riparian areas without beaver colonies were three times more affected by wildfire than riparian areas with beavers.
During the 2021 Colorado Beaver Summit, Dr. Fairfax explained that when beavers create wetlands, the surrounding vegetation and soil stay hydrated. During a fire event, the moist environment slows, smolders and redirects a fire away from the ecosystem, creating a haven for wildlife called refugia. Refugia is vital to the survival of vulnerable species that cannot easily escape fires, such as frogs, fish, plants, beavers and other small animals.
Dr. Fairfax’s research also suggests that beavers can create refugia during megafires, meaning high intensity fires that burn 100,000 acres or more of land at a time. Though once rare, megafires are increasingly common, with two of Colorado’s most destructive occurring in 2020: The Cameron Peak Fire (208,913 acres burned) and East Troublesome Fire (193,812 acres burned). Through remote sensing and rigorous data collection, Dr. Fairfax found that during both of these megafires beavers survived and preserved large sections of riparian habitat. Beaver complexes generated roughly 270 acres of refugia during the Cameron Peak Fire and 1,500 acres during the East Troublesome Fire.
In parts of the SLV, beavers could have the same protective effect against wildfires, though there is concern that local beaver populations have yet to recover from centuries of ruthless hunting and trapping. “Beavers are still here but they are not what they used to be…Anyone who hikes up to Willow Lake knows that beavers are not there, but they could be,” May shared. Working with a small team under the name E3KFM, May aims to revive beaver populations to sustainable and effective numbers, where appropriate and, in turn, rehydrate local forests and increase biodiversity.
In 2012, May initiated a survey with help from Colorado College to assess the presence of beavers around Crestone, from North Crestone Creek to Sand Creek. The results indicated that beavers occupied Spanish, Cottonwood, Sand Creek, Deadman and Willow Creeks. Shockingly, May’s most recent survey is preliminarily showing that beavers along these waterways have all vanished except for at high elevations along Sand Creek and possibly Deadman Creek.
May speculates that this sudden decline is due to habitat loss from agriculture, a dramatic drop in the water table and possibly hunting. He also lamented that beavers are still being treated as a nuisance in the Valley. May recalled that when he first announced his plan to bring back beaver a man approached him and said, ‘If you bring them back, I will shoot every one of them.’
E3KFM recently expanded its assessment of beavers through an aerial satellite search that scouted for beaver activity from the Great Sand Dunes to Poncha Pass. The results indicated that in the past 30-50 years, less than 10% of studied streams showed signs of well-established beaver activity. This summer, the aerial survey will be verified through site visits to 15 watersheds that were surveyed. In addition to looking for historic and current beaver activity, site visits will assess viable beaver habitat to inform possible future reintroduction plans. E3KFM is currently working with the Rio Grande National Forest Service to restore beaver habitat along Willow Park and Wilcox Gulch. E3KFM is also endeavoring to restore natural stream flows and floodplain connectivity in the local riparian zones. This is an important part of the work to rehydrate the area in partnership with beavers.
Within the Rio Grande National Forest (RGNF) beaver populations are reportedly stable and robust, though populations “are still significantly lower than they were historically,” said Rosalee Reese, a Fisheries Biologist with the U.S. Forest Service. She added that beaver decline is largely due to a history of extensive trapping and hunting in the area. Taos, NM was a major hub during the fur trade, with hunters dipping into the SLV in search of the species. Since the fur trade concluded in the late 1800s, beavers have started to recover and expand into new habitats.
RGNF manages beavers as a priority species, explained Reese, because beavers are both keystone species and indicators of riparian and aquatic habitat health. RGNF helps run a program to relocate beavers to suitable habitat on the RGNF when human/beaver conflicts arise. This is aiding in the restoration of the species to their historic range.
The Great Sand Dunes National Park and Preserve is also home to a stable population of beavers. “As a native species with a keystone role in our riparian systems, we are very interested in the wellbeing of beaver populations,” said Great Sand Dunes Biologist, Dewane Mosher. Mosher explained that beavers occupy the Medano Creek and Hudson Branch areas of the Great Sand Dunes. “We don’t have a formal population estimate,” Mosher commented, “but beavers fully occupy about 12 stream miles of year-round habitat,” including a fully occupied population on Medano Creek. “The beavers are a positive influence on native fish populations due to the diversity of habitats their presence promotes,” Mosher added.
For example, one of the healthiest populations of Rio Grande Cutthroat Trout, a candidate species under the Endangered Species Act (ESA), is found in Medano Creek. Ponds fed by beaver activity also provide vital spawning and nursery areas for Rio Grande Suckers, a State Endangered fish and candidate species under the ESA.
Mosher identified the Sand Creek drainage as once hosting beaver colonies, but after a large flood event 10 years ago, the creek has since been unoccupied. He is optimistic that beavers will reoccupy the creek from neighboring populations in the future. “Beaver populations are cyclical and fluctuate naturally due to changes in the habitat that are often caused by the beavers themselves,” explained Mosher. However, if natural reoccupation doesn’t occur, the Great Sand Dunes is open to a re-introductory plan along the drainage.
Beavers once inhabited nearly every year-round stream in North America, highlighting just how essential the species has been to the evolution and livelihood of countless species. Though populations are considered stable in some parts of the SLV, continued effort is required to help the species recover to sustainable and effective numbers, especially around the greater Crestone area. To learn more about E3KFM’s beaver restoration project, visit www.e3ecologic.org/current-projects.
The Sonic Apothecary in association with E3KFM and Shumei International will be hosting a future concert and workshop to restore a forest along Cottonwood Creek, called “Music and Mycelium.” Details will be at www.thesonicapothecary.com.