Bears
Human behavior leads to conflict with bears.
Habitat fragmentation is one of the most pressing ecological challenges of our time, and its consequences for wildlife are profound. While habitat loss itself is devastating, fragmentation adds an additional layer of harm by breaking continuous landscapes into smaller, isolated patches. These patches are often surrounded by human-dominated environments such as agricultural fields, roads, or urban areas, which act as barriers to movement. The result is a landscape that no longer functions as a connected system, but rather as a series of islands where species struggle to survive. Scientific research has consistently shown that fragmentation undermines biodiversity, reduces genetic diversity, and destabilizes ecological processes, making it a critical driver of extinction risk worldwide.
Haddad et al., 2015, found that habitat fragmentation reduces biodiversity by 13%-75% and harms important ecosystem functions by changing nutrient cycles and reducing biomass. Therefore, there is an urgent need to increase connectivity of landscapes to maintain ecosystem services and decrease rates of species extinctions.
The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), 2018, Summary for Policymakers Report on Land Degradation, found that humans have affected more than 75% of land area on the planet, and the resulting habitat loss and fragmentation are the primary causes of declines in biodiversity (IPBES, 2018).
One of the most immediate impacts of fragmentation is the loss of connectivity. Wildlife depends on connected habitats to migrate, forage, and reproduce. When landscapes are divided, animals are often unable to reach the resources they need. Large mammals such as elk, bears, and mountain lions require extensive ranges to maintain viable populations, and fragmentation restricts their ability to move freely. Even smaller species, such as amphibians or pollinators, suffer when their dispersal routes are blocked.
The isolation of populations has cascading effects on their survival. Smaller, fragmented populations might be more vulnerable to demographic fluctuations, disease outbreaks, and environmental changes. In ecological terms, they lack the “rescue effect,” where individuals from neighboring populations can recolonize patches after local declines. Once a population is lost from a fragmented patch, the likelihood of natural recovery is slim, and the species’ overall range contracts. Reed, 2004, used population models with demographic, environmental and genetic stochasticity from long-term data on 30 species of vertebrates. He concluded that habitat fragmentation will exacerbate the global extinction crisis and that conservation efforts should prioritize interconnecting isolated patches of habitat.
Genetic diversity is another casualty of fragmentation. When populations are cut off from one another, gene flow is restricted, leading to inbreeding and reduced adaptive potential. Genetic diversity is the raw material for evolution, enabling species to respond to changing environments, diseases, and climate pressures. Manley (2024) highlights case studies where fragmented populations of mammals and birds showed measurable declines in genetic diversity, undermining their long-term survival. In the absence of connectivity, even species that persist in fragmented landscapes may be locked into a genetic bottleneck, unable to adapt to future challenges.
Fragmentation also alters the physical and ecological character of habitats through edge effects. As large patches are broken into smaller ones, the proportion of habitat edges increases relative to interior habitat. Edges are often degraded environments, subject to higher predation, invasive species, and altered microclimates. For example, forest edges may be hotter, drier, and more exposed to wind, making them unsuitable for species adapted to stable interior conditions.
The International Fund for Animal Welfare (2025) notes that forest-dwelling animals have more access to more resources in the interior of the forest than its outer reaches and are therefore safer in the interior. The edge of forests often have more plant life, which requires more sunlight and often require less water; hence, the abundance of plants for herbivores is affected by habitat edges.
Distinguishing between habitat loss and habitat fragmentation is key to questions about the loss of biodiversity and the most effective mitigation strategies. Fahrig et al. (2017) found that ecological responses to fragmentation per se, which is fragmentation independent of habitat amount, were usually non-significant and that 75% of significant effects were positive. Fletcher et al. (2018) refute the findings of Fahrig et al. (2017) by extrapolating from patch-scale data to landscape-scale effects of fragmentation. Fahrig et al. (2019) argue that such extrapolation is unsound, and that future research should address landscape-scale empirical studies of the effects of habitat fragmentation per se.
Chetcuti et al. (2020) found that while fragmentation sometimes increases overall species richness, this apparent gain is misleading: habitat-dependent species decline sharply due to edge effects and patch isolation, while generalist species proliferate. The result is a homogenization of biodiversity, where specialists disappear and ecosystems lose their complexity.
Beyond individual species, fragmentation disrupts ecological processes that sustain entire ecosystems. Predator-prey dynamics, pollination, seed dispersal, and nutrient cycling all depend on movement across landscapes. When these processes are interrupted, ecosystems lose resilience.
The long-term consequences of fragmentation are sobering. Many species experience what ecologists call “extinction debt,” where populations persist temporarily in fragmented habitats but are doomed to eventual extinction due to insufficient population sizes and connectivity. Community composition shifts as generalist species thrive while specialists decline, leading to ecological homogenization. In extreme cases, fragmentation can trigger ecosystem collapse, as the loss of keystone species undermines the stability of entire systems. These changes reduce not only biodiversity but also the ecosystem services upon which humans depend, such as carbon storage, water purification, and soil fertility.
Taken together, the evidence demonstrates that habitat fragmentation is not merely a byproduct of habitat loss but a distinct ecological threat. While some species may temporarily benefit from increased edge habitats or novel niches, the overwhelming weight of peer-reviewed research shows that fragmentation undermines biodiversity and ecosystem stability. Specialist species, such as forest-dependent birds or large carnivores, are disproportionately harmed, while generalists may increase, leading to a less diverse and less resilient ecological community. Genetic isolation further reduces adaptive capacity, making populations less able to withstand climate change, disease, or human pressures.
In conclusion, habitat fragmentation is bad for wildlife because it isolates populations, reduces genetic diversity, increases extinction risk, and disrupts ecological processes. Peer-reviewed research confirms that fragmentation is a global driver of biodiversity decline, compounding the effects of habitat loss. Protecting large, connected landscapes and restoring ecological corridors are essential strategies to mitigate these impacts and ensure the survival of wildlife in the Anthropocene. As human development continues to expand, the challenge for conservationists and policymakers is to balance growth with ecological integrity, recognizing that connectivity is not a luxury but a necessity for the persistence of life on Earth.
Haddad, N.M. et al., 2015, Science Advances.
Reed , David. (2004). Extinction risk in fragmented habitats. Animal Conservation.
Manley, K. 2024, Journal of Biodiversity & Endangered Species.
Chetcuti et al., 2020, Frontiers in Ecology and Evolution.
Fahrig et al., 2017, Annual Review of Ecology, Evolution, and Systematics.
Across the American West, livestock grazing on public lands has become a deeply entrenched practice—one that is ecologically damaging, economically inefficient, and politically protected. This system persists not because it serves the public interest, but because it is heavily subsidized by taxpayers and shielded by outdated policies and cultural myths.
The practice of grazing cattle and sheep on federal lands is often romanticized as a symbol of rugged individualism and frontier heritage. In reality, it relies on a complex web of government support. Ranchers pay grazing fees far below market rates—often less than $2 per animal unit month—while the true cost of managing these lands, including infrastructure, monitoring, and damage mitigation, is borne by the public. The true cost to the public of livestock grazing on U.S. public lands is estimated at over $1 billion per decade — or approximately $125 million per year. Additional subsidies include predator control programs, fencing, water development, and fire suppression, all designed to prop up an industry that contributes minimally to the national economy.
The environmental consequences are profound. Livestock grazing is one of the most widespread and ecologically disruptive land uses in the West. It degrades riparian zones, compacts soils, spreads invasive species, and disrupts native plant communities. Streambanks are trampled, water quality declines, and the habitat for fish, amphibians, and birds is severely compromised. In arid and semi-arid regions, where water is scarce and biodiversity is concentrated along waterways, the impact is especially severe.
Wildlife suffers as well. To protect livestock, federal agencies routinely kill predators such as coyotes, wolves, and mountain lions—even on lands designated for conservation. This systematic removal of apex predators destabilizes ecosystems, leading to trophic cascades that further erode ecological resilience. Species like beavers, which play a critical role in water retention and habitat creation, are displaced or eliminated. Ground-nesting birds, including the imperiled sage grouse, lose critical breeding grounds to overgrazed landscapes.
The economic rationale for continuing this system is increasingly untenable. The revenue generated from grazing fees is dwarfed by the costs of administering the program and repairing the damage it causes. Estimates suggest that taxpayers subsidize public lands grazing by approximately $125 million annually. Meanwhile, the ecological services lost—such as water filtration, carbon sequestration, and biodiversity—represent an even greater hidden cost.
Despite these realities, reform has been slow. Federal agencies like the Bureau of Land Management and the U.S. Forest Service have historically prioritized ranching interests, often at the expense of science-based land management. Political pressure from powerful industry groups has stymied efforts to reduce grazing or retire permits. In many cases, public lands are managed not for the benefit of all citizens, but for the narrow interests of a small number of permit holders.
However, alternatives exist. Some conservationists advocate for voluntary permit buyouts, where ranchers are compensated to relinquish their grazing rights. This approach allows for ecological restoration without forcing conflict. Others call for a complete phase-out of grazing on public lands, arguing that these landscapes should be managed for ecosystem health, recreation, and climate resilience.
Grassroots movements have emerged to challenge the status quo. Environmental organizations, scientists, and local activists have documented the damage caused by grazing and pushed for legislative and administrative change. Their efforts have led to the closure of some grazing allotments, the protection of sensitive habitats, and increased public awareness of the issue.
The broader cultural narrative is also shifting. As public values evolve, there is growing recognition that the American West’s future depends not on preserving outdated economic models, but on restoring its ecological integrity. The myth of the cowboy is giving way to a new vision—one that sees wildlands not as resources to be exploited, but as living systems to be protected.
Ultimately, the continued subsidization of livestock grazing on public lands represents a failure of policy, science, and ethics. It is a system that benefits a few while imposing lasting costs on ecosystems, taxpayers, and future generations. Ending this practice—or at the very least, reforming it—requires political will, public engagement, and a commitment to managing land in the public trust. The path forward lies in aligning land use with ecological knowledge, economic logic, and a shared responsibility for the health of the American West.
Welfare Ranching, 2002, Wuerthner and Matteson.
Study Reveals Livestock Grazing on Public Lands Cost Taxpayers $1 Billion Over the Past Decade, January 29, 2015, American Wild Horse Conservation.
Public Lands Welfare Ranchers Again Subsidized By Taxpayers, May 31, 2025, “The Wildlife News,” Wuerthner.
Climate, Ecological, and Social Costs of Livestock Grazing, 2023, Kauffman et al.
Meta-Analysis of Ecosystem Impacts, 2022, Kauffman et al. https://www.westernwatersheds.org/wp-content/uploads/2025/10/Kauffman-et-al-2023.pdf
Economic, Social, and Environmental Impacts, 2021, Oerly et al. https://repository.arizona.edu/bitstream/handle/10150/675730/S019005282100119X.pdf?sequence=1
Public Employees for Environmental Responsibility (2022) – Land Health Standards, March 21, 2022, American Wild Horse Conservation.
Thousands of animals are trapped and killed each year in Colorado. To trap most animals with fur in Colorado, you need to purchase a “furbearer license only,” for $36.68 for residents and $101.54 for non-residents, plus a “furbearer harvest permit” add-on for about $10, after purchasing a “small game license” for $35.76 for residents.
Proposition 127 on the 2024 Colorado ballot asked voters if they wanted to prohibit trophy hunting of mountain lions and trapping and hunting of bobcats. The proposition lost, with 54.7% votes opposed. To understand the reasons the proposition lost, Neimec et al., 2024, conducted interviews with voters throughout the state and found that the most common reason (26.9% voters) voters opposed the proposition was they thought wildlife management decisions should be left to the experts, i.e., Colorado Parks & Wildlife (CPW). The next most common reasons voters gave were: cats are already managed well by CPW (17.5%); desire to avoid “ballot box biology” in which the public vote on wildlife decisions (13.1%), and they trust CPW (13.1%).
Niemec et al., 2025, found that 64% & 62% Americans oppose trapping of larger carnivores like coyotes and bobcats, and smaller ones like foxes and raccoons, respectively; and that
83% & 79% Americans oppose unlimited killing of larger carnivores like coyotes and bobcats, and smaller ones like foxes and raccoons, respectively.
In May 2025, CPW decided to hold a process of engaging stakeholders with a facilitator to discuss possible changes to “furbearer harvest policy” for these species: badger, bobcat, coyote, gray fox, long-tailed weasel, mink, muskrat, marten, opossum, raccoon, red fox, ringtails, short-tailed weasel, striped skunk, swift fox, and western spotted skunk. (Although beavers are currently managed similarly to these species, changes to their management are being explored separately by CPW. Beavers were therefore excluded from CPW stakeholder this process. Beavers are discussed here on the SCW web site.)
CPW selected people to participate in one of two focus groups to explore possible changes to the agency’s management of “furbearer” animals. Group A was composted of the livestock industry and hunters and trappers. Group B was composed of wildlife conservation and animal welfare representatives. On Nov. 30, 2025, CPW released the Colorado Parks and Wildlife Furbearer Stakeholder Process Management & Policy Recommendations, Final Report. The report’s recommendations primarily maintain the status quo by allowing continued unlimited trapping and hunting, except to establish limits of four species (swift fox, gray fox, ringtails, and marten). Recommendations are:
On Dec. 16, 2025, the Center for Biological Diversity (CBC) published a report, Moving to Modernize: Five Steps to Update Colorado’s Furbearer Management, which makes five helpful recommendations that are steps in the right direction. CBD recommends:
Each of these species serves important roles in maintaining a healthy ecosystem. None of these species’ population would grow too high if they were not trapped and hunted by humans. These animals should not be trapped or hunted.
Animals with fur, which trappers and CPW calls “furbearers,” is an objectifying term based on humans’ exploitation of these animals. This category is not based on scientific taxonomy.
Many furbearers are mesopredators, but these terms are not synonymous. The terms describe animals based on different criteria, though many species fall into both categories.
Many common species, such as raccoons, bobcats, foxes, and skunks, are considered both furbearers due to their valuable pelts and mesopredators due to their intermediate ecological role. The key difference lies in the definition: one is an anthropogenic classification, and the other is an ecological one.
American badgers (Taxidea taxus) are ecosystem engineers that provide significant benefits to ecosystems in Colorado. American badgers weigh 10-30 pounds, and have long claws for digging and strong, short legs. They control rodent populations—e.g., gophers and squirrels—and maintain predator-prey balance in grasslands and shrublands. American badgers aerate soil by digging, thereby improving water filtration and plant growth. They create shelter for other species, disperse seed, and act as habitat indicators for overall ecosystem health. Andersen et al., 2021, found that 31 other species utilize badger burrows: 12 mammals, 18 birds, and 1 reptile. Minta et al., 1992, found that coyotes associating with badgers were more successful hunting Uinta ground squirrels than were lone coyotes. (Minta et al., 1992; Andersen et al., 2021). Threats to badgers include vehicular collisions, habitat loss, mass killing of their preferred prey–prairie dogs—and trapping. They are legally trapped and hunted in unlimited numbers in Colorado from Nov. 1 – February 28 (or 29).
The North American beaver (Castor canadensis) is one of two species of beaver. The population of beaver in North America before European colonization was estimated 60-400 million. Beavers lived in wetlands and riparian habitat from the Pacific coast to the Atlantic coast of the contiguous United States. Fur trappers in the 1700s and 1800s killed so many beavers in North America, to sell fur primarily to Europeans for hats, that they reduced the beaver population by 85%-95%. Beavers in North America were trapped almost to extinction before 1900. (Baker and Hill, 2003).
Beavers were reintroduced into much of their former range in the mid-1900s. Beavers are now estimated to have a population of 6-12 million in North America. (Naiman et al., 1998). However, 195,000-260,000 km2 of wetlands have been converted to agricultural or other use in the United States, thereby significantly reducing available beaver habitat.
Beavers are the largest rodent native to North America. Adult beavers weigh 40-50 pounds and are 3-4 feet long. When not trapped or otherwise hunted, they live 10-12 years in the wild. They are social animals and mate for life. They give birth to 1-6 kits (babies) annually in the spring. Kits weight about one pound at birth. Kits live with their families for 1-2 years before searching for their own habitat.
Beavers are vegetarian and eat the inner bark of willow, aspen, cottonwood and other riparian trees, as well as grasses and sedges. In autumn, beavers store food in the bottom of their ponds that they will eat in the winter. They leave their pond in the winter only if they eat all of their stored food.
Beavers are hydrologic engineers and are essential for climate resilience, scientists have found. (Fairfax and Westbrook, 2024; Brazier, R.E. et al., 2020; Rozhkova-Timina, O., et al., 2018; Larsen, A., et al., 2021; Rubin-Thomas and Blackledge, 2023). Beavers have a significant effect on the form and function of the natural environment. They build dams and lodges that host freshwater fish, aquatic mammals, waterfowl, migratory birds, reptiles, amphibians, invertebrates, and plants.
Beavers are a keystone species, and they serve essential roles in maintaining healthy ecosystems. (A keystone species is one on which other species in an ecosystem largely depend. If a keystone species is removed, the ecosystem changes dramatically.) Their dams raise water levels, slow water speed, and change water direction, thereby increasing the area of a wetland, diversity of species, and increasing quality of water by stabilizing and reducing water temperature, and reducing eutrophication.
Fairfax and Westbrook, 2024, describe the three main ways that beavers engineer their environment:
Fairfax and Westbrook, 2024, describe six ways that beavers ameliorate anthropogenic climate change.
Despite being a keystone species, and one that significantly ameliorates anthropogenic climate change, it is legal to trap and hunt unlimited numbers of beavers in Colorado Oct. 1-May 1.
Bobcats (Lyxn rufus) live throughout a variety of habitats in North America, including deserts, forests, and suburban borders. Females usually weigh 12-25 pounds, whereas males typically weigh 20-35 pounds. They are mesopredators (a mid-ranking predator) that benefit ecosystems by regulating populations of small prey, such as rodents and rabbits. (Verdi, 2025). In Colorado, bobcats are more likely to live in the mountains, forests, tundra, and wetlands. Mothers give birth to two to four kittens in spring.
Bobcats look very much like Canada lynx, which are threatened (as listed on the Endangered Species Act). Nonetheless, CPW allows bobcats to be trapped and hunted in habitats where Canada lynx live.
Elbroch et al. (2017) report a value of a live bobcat in Yellowstone National Park of $308,105 for the 2015-2016 winter season, which is more than 1,000 times greater than the money a trapper or hunter obtains after killing the bobcat and selling its fur, which retails for $135.17.
Threats to bobcats include ingestion of poisons (rodenticides) that people distribute on the land, as well as increased wildfire frequency and precipitation changes that modify habitat suitability for bobcats. Habitat loss and fragmentation are another threat to bobcats. Vehicular collisions kill many bobcats every year. (Tigas et al., 2002). The greatest threat to bobcats in Colorado is the unlimited trapping and hunting that is legal. Bobcats are the only animals with fur for which trappers and hunters are required to show CPW the bodies or pelts (fur) of bobcats they’ve slaughtered. Bobcat pelts are required to be inspected and sealed before the trappers and hunters are allowed to transport or ship them outside of Colorado. Trappers and hunters reported killing 1,273 bobcats in the 2024-2025 season, and killing 918 bobcats in the 2023-2024 season. It is legal to trap and hunt unlimited numbers of bobcats Dec. 1-February 28 (or 29) in Colorado.
Coyotes (Canis latrans) in the western United States weigh 18-30 pounds; whereas those in the eastern part of the county weigh 35-50 pounds because they’re interbred with eastern wolves and domestic dogs. Coyotes are social and intelligent. They hunt in the day and night, and are monogamous and devoted parents. (Bekoff and Gese, 2003). They can run 25-40 mph and are adept climbers. Coyotes show a wide range of emotions, including playfulness, curiosity, and grief. (Project Coyote, 2025).
Coyotes are a keystone species and benefit ecosystems significantly by regulating populations of rodents and rabbits, thereby reducing the spread of diseases these prey carry. Coyotes also scavenge carrion, and help birds by preying on foxes, skunks, and raccoons. Coyotes increase biodiversity in ecosystems by regulating populations of prey and minimizing spread of diseases.
Despite being a keystone species, coyotes are the most persecuted native carnivore in North America. The USDA Animal Plant Health Inspection Service reports more than 500,000 are slaughtered every year in the United States. (Project Coyote, 2025). Such persecution and killing has existed for a long time. James Galen, superintendent of Glacier National Park in 1913, wrote, “I am desirous of inoculating, with mange, some coyotes to turn loose here in the par, with the idea that I may eventually kill off all the coyotes in the park in this manner.” Galen proceeded to try to kill all the coyotes by introducing mange, but the USDA thought poisons would be even more lethal. In 1923, the Bureau of Biological Survey set out 31,255 poison bait stations in Colorado. (Flores, 2016). It is legal to trap and hunt coyotes year-round in Colorado.
Threats to coyotes include mange, poisoning, vehicular collisions, legal year-round unlimited killing by citizens and by USDS APHIS “Wildlife Services,” and illegal killing.
Gray foxes (Urocyon cinereoargenteus) weigh 7 – 15 pounds. Mothers give birth to 3-7 kits in the spring (April and May). They help regulate populations of small mammals, birds, and insects, reducing pest pressure in forest ecosystems. Their omnivorous diet includes fruits and seeds, contributing to seed dispersal and forest regeneration. Gray foxes provide rodent control in agricultural and suburban areas, reducing crop damage. Their climbing ability allows them to exploit arboreal food sources, influencing nut and fruit dispersal. Their presence supports biodiversity and reduces disease risk associated with rodent overpopulation. (Wilson and Thomas, 1999; Webster et al., 2021).
Threats to gray foxes include habitat loss and fragmentation, disease, poisons (rodenticides), and unlimited trapping and hunting. (Allen et al., 2021). In Colorado, it is legal to kill an unlimited number of gray foxes in Nov. 1- February 28 (or 29).
Long-tailed weasels (Mustela frenata) weigh between a quarter of a pound up to a pound, with females weighing about half as much as males. In Colorado, they live in forests, grasslands, and wetlands. Mothers give birth to 4-9 babies in the spring (April and May). They play an essential role in ecosystems of North America by regulating mammal populations, e.g., mice, voles, and ground squirrels. The long-tailed weasel also facilitates nutrient cycling and energy transfer in ecosystems, transferring nutrients and energy from lower to higher trophic levels. The long-tailed weasel thereby prevents the accumulation of carcasses and reduces the risk of disease transmission. (Jachowski et al., 2021). Threats to long-tailed weasels include poisons, habitat loss and fragmentation, vehicular collisions, and unlimited trapping and hunting. In Colorado, it is legal to trap and hunt from Nov. 1-February 28 (or 29).
Short-tailed weasels (Mustela erminea) weigh between one eighth of a pound and one half of a pound, with males weighing about 50%-100% more than females. Compared to long-tailed weasels, the short-tailed kind prefer higher elevation and cooler temperatures and similarly benefit ecosystems in Colorado and throughout North America. Like the long-tailed weasel, the short-tailed weasel regulates populations of rodents, which reduces those rodents’ impacts on plants and risk of disease transmission. (Marneweck et al., 2021). Threats to short-tailed weasels include poisons, habitat loss and fragmentation, vehicular collisions, and unlimited trapping and hunting. In Colorado, it is legal to trap and hunt short-tailed weasels from Nov. 1-February 28 (or 29).
The American marten (Martes americana), also called the American pine marten, lives in Canada, Alaska, and the northern United States. An American marten is about the size a mink, weighing 1-3 pounds; males weigh up to 65% more than females. Adult American martens are usually solitary except during the breeding season of July and August. Mothers give birth to 1-5 kits in late March or April. American marten benefit ecosystems by regulating populations of small mammals, including voles, deer mice, and shrews, thereby reducing the risk that those populations become so large that they damage vegetation. American martens also benefit ecosystems by inadvertently carrying seeds in their fur, thereby dispersing seeds to yield new vegetation and increasing biodiversity. (Buskirk, S. et al., 1994). Forest management and climate change also threaten the American marten. (Suffice et al., 2017). Threats include habitat loss and fragmentation, poisons, loss of forests to increased wildfires and beetle kill. Despite allowing so many trappers and hunters to kill so many marten that marten were listed as endangered in Colorado from 1995-2006, CPW now allows unlimited trapping Nov. 1-February 28 (or 29).
Mink (Neogale vison, formerly neovison vison or Mustela vison) weigh between 1 ½ to 3 ½ pounds, with females weighing about half as much as do males. Mothers give birth to 4-6 kits each spring. They build dens near rivers and streams. In the western United States contribute to ecosystem services through prey regulation, nutrient cycling, and serving as indicators of riparian health. Peer-reviewed studies confirm these roles, though their ecological benefits can be weighed against potential risks to sensitive species. In native western U.S. habitats, mink provide ecosystem services by maintaining balance in riparian food webs; however, in non-native habitats, mink can cause ecosystem disservices by predating on sensitive species of waterfowl or amphibians.
Mink is a sentinel species indicating environmental health and presence of toxins. By reviewing the pertinent literature from exposure- and effects-based studies, Basu et al., 2007, study mink as a proxy for the presence of mercury (Hg) and polychlorinated biphenyls (PCBs) in the environment, as they are persistent, ubiquitous, and bioaccumulative contaminants of concern to both humans and wildlife. Mink indicate environmental pollution on both temporal and spatial scales. (NOAA, 2018).
Threats include habitat loss, water pollution, poisons, and unlimited hunting and trapping. In Colorado, it is legal to hunt and trap unlimited mink Nov. 1-February 28 (or 29).
Muskrats (Ondatra zibethicus) weigh 2-4 pounds and are 18-25 inches long, including their 8-11-inch tails. Usually dark brown, they are rarely almost white or black. Their hind feet are partially webbed, and they live in still or slow-moving waterways, including beaver ponds and marshy borders of rivers and lakes. Muskrats are potential allies to solving invasive aquatic plant problems. Muskrats play important roles in ecosystems. They harvest plants for their dens and for food, thereby creating open water for waterbirds and other wildlife. Snakes, turtles, frogs, ducks, and geese rest and nest in muskrat lodges and platforms. Muskrats create huts with underwater entrances that provide nesting platforms for Trumpeter Swans. Muskrats breed in the spring and sometimes raise up to three broods in a season. A pair of muskrats may raise 10 or more pups in a year, but up to 90% die from trapping, hunting, predation, and disease. They are now an indicator for degradation and loss of wetlands in the United States. (Jones et al., 2022). Threats include habitat loss, water pollution, and unlimited trapping and hunting. In Colorado, it is legal to trap and hunt unlimited numbers of muskrats from Nov. 1-February 28 (or 29).
Virginia opossums (Didelphis virginiana) weigh up to 7.5 pounds, and are about the size of a domestic cat. Each of their feet has an “opposable toe” that allow opossums to hold things in the same manner humans hold things with their hands. Opossums do not hibernate and are nocturnal. They live in burrows made by other animals, hollow trees, and under rocks, especially in the eastern part of the state.
Opossums are Colorado’s and North America’s only marsupial. Breeding starts in January. Females have two litters of about 5 to 15 babies each year. Babies crawl into the mother’s pouch, where they develop for about three months. Few survive to adulthood.
Opossums benefit ecosystems by eating carrion, roaches, rates, mice, and ticks. One opossum can eat 5,000 ticks in a season. Opossums help reduce the spread of diseases. (Kirchner, 2021).
Urban opossums remove rodent carcasses, reducing disease risks. In forest settings, they have been shown todisperse viable seeds, aiding forest regeneration. Opossums’ role in tick control is supported in natural settings. Additionally, the literature notes their role in reducing pathogens that affect people, pets and livestock. (Bezerra-Santos et al., 2021; Glebskiy, O., and Cano-Santana, Z., 2023).
Threats include vehicular collisions, trapping and hunting. In Colorado, unlimited trapping and hunting is legal Nov. 1-February 28 (or 29).
Raccoons (Procyon lotor) weigh between 10 and 30 pounds, with males generally weighing more than females. They live in cities, suburban neighborhoods, agricultural lands, and riparian areas. Mothers give birth to 3-5 kits in the spring. Raccoons act as primary dispersal agents, depositing seeds far from parent plants; their dung then facilitates secondary dispersal, enhancing microsite diversity and seedling survival. Niederhauser and Matlack, 2017,embedded mayapple (Podophyllum peltatum) seeds in raccoon dung in a deciduous forest. They found that about 15% of seeds were moved over 20 cm from dung sites by abiotic factors (rain, gravity) and animal vectors (e.g., mice, chipmunks). Raccoons play a critical role in carrion removal, helping to maintain ecosystem sanitation, curb disease spread, and support nutrient cycling. Their removal leads to measurable decreases in ecosystem function. (Olson et al., 2011; Niederhauser and Matlack, 2017).
Threats to raccoons include vehicular collisions, outbreaks of rabies and distemper, poisons, habitat loss and fragmentation, and unlimited trapping and hunting. In Colorado, unlimited trapping and hunting is legal from Nov. 1-February 28 (or 29).
Red fox (Vulpes vulpes) usually weigh 7-15 pounds, with males usually weighing more than females. They live in urban, suburban, woodlands, agricultural and riparian areas. Mothers give birth to 3-6 kits in early spring (March and April). Red foxes provide significant benefits to ecosystems in Colorado by controlling (eating) mice, gophers, and rabbits; dispersing seeds; and influencing soil nutrients.
Red foxes are recognized as generalist carnivores that help regulate populations of small mammals and invertebrates, which contributes to biodiversity control and ecosystem balance. Their distribution patterns, influenced by landscape features and competition dynamics (e.g., with coyotes), hint at their role in structuring urban and agricultural ecosystems.
Red foxes coexist with coyotes by partitioning habitat use, contributing to spatial structure and ecosystem stability in urban environments. Their presence in urban areas aids in regulating rodent and small mammal populations, enhancing human-wildlife coexistence. Red foxes maintain predator-prey dynamics by relying on snowshoe hares, jackrabbits, pika, and cached pine nuts—facilitating niche partitioning and ecosystem stability in high-elevation areas. (Mueller et al., 2018; Rosburg-Francot et al., 2025). Threats to red foxes include vehicular collisions, poisons (rodenticides), and unlimited trapping and hunting. In Colorado, unlimited trapping and hunting are legal Nov. 1-February 28 (or 29).
Ringtail cat (Bassariscus astutus) is a member of the raccoon family and weighs between 1.5 and 3.3 pounds. They are nocturnal and seldom seen by people. They have tails that are about 12-17 inches (the same length as their bodies), which have 14-16 black and white rings (stripes). They live in southern and western Colorado, particularly in pinyon-juniper woodlands, riparian areas, and rocky canyons. Mothers give birth to 1-5 kits in spring to early summer. Ringtails benefit ecosystems in Colorado by controlling (eating) mice, pack rates, and insects. By improving germination success and promoting seedling recruitment, ringtail cats help sustain specific plant populations, which contributes to ecosystem resilience and diversity in temperate oak forests. Urban ringtails disperse a wider array of species, including exotic plants, through microhabitats created by urban infrastructure. This enhances plant species richness in otherwise low-diversity environments. (Peña‑Herrera et al., 2025; Gundermann et al., 2023).
Threats to ringtail cats include vehicular collisions, poisons (rodenticides), habitat loss and fragmentation, and unlimited trapping and hunting. In Colorado, unlimited trapping and hunting are legal Nov. 1-February 28 (or 29).
Striped skunks (Mephitis mephitis) live in much of North America. Adults weigh between 4-10 pounds, and males weigh about 10% more than females. Like all skunks, they have two musk-filled scent glands to ward off predators. Mothers give birth to 4-7 kits in May. They benefit ecosystems by regulating insects, like grasshoppers and grubs, mice and voles that eat native plants and crops; aiding seed dispersal and nutrient cycling through their varied diet (berries, carrion), and serving as a food source for predators, thereby supporting overall biodiversity and ecosystem health in foothills and canyons. They act as key food web connectors, helping balance populations and recycle nutrients. Striped skunks eat insects and rodents that damage crops. (Dragoo, 2009). Threats include vehicular collisions, rabies and distemper, rodenticides, and trapping, which is legal in Colorado Nov. 1-February 28 (or 29).
Western spotted skunks (Spilogale gracilis) live in the western United States. Males weigh from 0.75 pound to 1.5 pounds, and females weigh from 0.5 pound to about 1 pound. Despite their name, adults are striped with black and creamy white, with three long stripes on each side of the front of the body, and three vertical stripes on the back part of the body. Mothers give birth to 2-5 babies in May. In Colorado, they live in foothills, rocky canyons, and riparian areas generally below 8,000 feet elevation. They provide significant benefits to Colorado ecosystems by regulating populations of their prey, e.g., rodents, insects, grubs, small amphibians and reptiles; dispersing seeds; aerating soil; and being a food source for other animals, including Golden eagles, owls, and coyotes, thereby stabilizing food webs and facilitating biodiversity. (Tosa et al., 2024). Threats include vehicular collisions, poisons (rodenticide), non-targeted trapping Nov. 1-February 28 (or 29).
Swift fox (Vulpes velox) live in less than 40% of their historic range in Colorado, and survive in fragmented populations, notably in the Pawnee National Grasslands. They weigh from 4-8 pounds, with males often weighing a bit more than females. Mothers give birth to 3-6 babies in the spring (March and early April). Swift fox survival and population density are linked to vegetation structure and habitat heterogeneity in shortgrass prairie. These foxes are habitat specialists; maintaining open prairie through disturbance regimes enhances their role as mesocarnivores that regulate prey populations, thus contributing to ecosystem balance. Reintroduced swift foxes preferentially select areas with high grass cover, suitable soil, and abundant prairie dogs. This behavior supports ecosystem processes such as predator–prey regulation, habitat restoration, and soil–grassland maintenance. They help preserve grassland biodiversity and ecosystem functioning through their ecological niche. (Gese and Thompson, 2014). They eat rabbits, mice, ground squirrels, birds, amphibians, lizards, insects, fruits, and grasses. They use and expand dens from prairie dogs, badgers, and other animals. Their presence is an indicator of a functioning shortgrass prairie ecosystem. Threats to swift fox include habitat fragmentation, vehicle strikes, disease, rodenticides, altered fire regimes, and unlimited trapping and hunting. CPW lists the swift fox as “state special concern,” but still allows unlimited trapping and killing of them Nov. 1 – February 28 (or 29).
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Buskirk, S, and Ruggiero, L. 1994. Chapter 2: American Marten. In The Scientific Basis for Conserving Forest Carnivores: American Marten, Fisher, Lynx, and Wolverine in the Western United States. USDA. General Technical Report RM-254. https://dn790008.ca.archive.org/0/items/CAT10689660/CAT10689660.pdf
Dragoo, J. 2009. Veterinary Clinics of North America: Exotic Animal Practice. “Nutrition and Behavior of Striped Skunks.” https://www.sciencedirect.com/science/article/abs/pii/S1094919409000140
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Galletta, L., et al., 2025, “Lethal control of semi-arid, red fox populations fails to reduce their abundance but may create increased fox activity,” Biological Invasions.
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Gese & Thompson (2014) PLOS ONE. Does Habitat Heterogeneity in a Multi‑Use Landscape Influence Survival Rates and Density of a Native Mesocarnivore? https://doi.org/10.1371/journal.pone.0100500
Glebskiy, O., & Cano-Santana, Z. (2023). Mammalia, 87(4), 357–364. Opossums cleaning our cities: consumption of rodent carcasses in an urban reserve. https://doi.org/10.1515/mammalia-2023-0069
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Jones, S., R.C. Cushman, and S. Severs. 2022. “December Nature Almanac: Muskrats Cozy up in Winter.” https://www.boulderaudubon.org/articles/dec-2022-na#:~:text=Besides%20being%20warm%20and%20cozy,action%20from%20violent%20summer%20thunderstorms.
Kirchner, J. 2021. “Opossums: Unosung Heroes in the Fight Agains Ticks and Lyme Disease.” https://blog.nwf.org/2017/06/opossums-unsung-heroes-in-the-fight-against-ticks-and-lyme-disease/
Larsen, A., et al., 2021, “Dam builders and their works: Beaver influences on the structure and function of river corridor hydrology, geomorphology, biochemistry and ecosystems,” Earth-Science Reviews.
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Miller, S. 2025. “Moving to Modernize: Five Steps to Update Colorado’s Fur-Bearer Management.” https://biologicaldiversity.org/programs/carnivore-conservation/pdfs/Furbearer-Report_5-Steps-to-Modernize_Final.pdf
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National Oceanic and Atmospheric Administration, 2018, Fact Sheet: Hudson River Trustees, Mink Injury Publication.
Niemec, R., M. Gonzalez, and J. Brager. 2024. “Colorado Voter Perspectives on an Initiative to Ban Hunting and Trapping of Mountain Lions, Bobcat, and Lynx.” https://drive.google.com/file/d/1_7eAHNCuo-8ZEbVla5kzr0a2AARgFPWn/view
Niemec, R., L. Kogan, A. Royall, M. Lute, and M. Wilson. 2025. “The Impact of Messaging on Public Support for Carnivore Protection Ballot Initiatives.” https://drive.google.com/file/d/1bb3ogBzw8QJ-DbS-4ipKeDyYD5NGjJaC/view?pli=1
Peña‑Herrera et al. (2025) – Revista Mexicana de Biodiversidad. Seed dispersal in urban to natural gradients. ttps://doi.org/10.22201/ib.20078706e.2024.95.5351
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Rosburg-Francot et al. (2025) – Molecular Ecology. Do snow-adapted prey facilitate coexistence of the Sierra Nevada red fox with sympatric carnivores? https://doi.org/10.1111/mec.70087
Rozhkova-Timina, O., et al., 2018, Beavers as ecosystem engineers – a review of their positive and negative effects. IOP Conf. Ser.: Earth Environ. Sci.
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Suffice, P. et al., 2017, “More fishers and fewer martens due to cumulative effects of forest management and climate change as evidenced from local knowledge,” J Ethnobiology Ethnomedicine.
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Mountain lions (Puma concolor) are a keystone species, meaning their presence supports the health and stability of entire ecosystems. Their influence extends far beyond their population numbers.
Their kills feed scavengers, enrich soil nutrients, and sustain beetle and insect populations.
By maintaining prey populations, they indirectly support plant regeneration and biodiversity.
Estimated at 30,000–50,000 across 16 western U.S. states, mountain lion numbers are stable or declining (Elbroch, 2022).
Attacks on humans are extremely rare — only 28–29 incidents in the past 150 years, fewer than deaths from lightning strikes each year.
Hunting is unnecessary for population control but is still allowed in most states for sport. Once adult territories are established, populations naturally stabilize.
Current Threats: Hunting with Hounds: Disrupts population balance and causes unnecessary suffering.
Diseases: Plague and Avian Flu have been recorded in wild populations, including a 2023 case near Teton National Park.Research indicates potential zoonotic exposure in ecosystems where pumas roam.
Elbroch LM, Vickers TW, Quigley HB. Plague, pumas and potential zoonotic exposure in the Greater Yellowstone Ecosystem. Environmental Conservation 47: 75–78 (2020). La Barge, L.R. et al. Pumas as Ecological Brokers: A Review of their Biotic Relationships. Mamma Review 52(3): 360–76 (2022).
Barry, J.M. et al. Pumas as Ecosystem Engineers: Ungulate Carcasses Support Beetle Assemblages. Journal of Wildlife Management (2019).
Peziol, M. et al. Large Carnivore Foraging Contributes to Heterogeneity in Nutrient Cycling. Landscape Ecology 38(6): 1497–1509 (2023).
Elbroch, L.M. & Harveson, P.M. It’s Time to Manage Mountain Lions in Texas. Wildlife Society Bulletin (2022).
Mountain Lion Foundation: Essential Guide to Recent Scientific Research on Mountain Lions, (mountainlion.org).
Human behavior leads to conflict with bears.
Black bears (Ursus americanus) are the most widely distributed bear species in North America, thriving across diverse habitats due to their adaptability, omnivorous diet, and flexible behavior.
The American black bear ranges from northern Mexico through most of the United States and into Canada, occupying forests, swamps, and mountainous regions. Their distribution is shaped by habitat quality, food availability, and human pressures. Habitat models show that black bear density varies widely, from as few as 8 to as many as 35 bears per 100 km² depending on resource abundance and landscape connectivity. (Welfelt, 2019.) Forest management practices, such as prescribed fire, can enhance habitat quality by increasing food diversity and denning opportunities. (Weaver, K., 1999.)
Black bears are omnivores with diets that shift seasonally. In spring, they consume emerging vegetation; in summer, berries and insects dominate; and in fall, they rely heavily on mast crops, which are nuts and fruits produced by trees including hickories, beeches, and oaks. Consuming mast crops allow bears to build fat reserves for winter dormancy. (Clark, J. et al., 2020). Their opportunistic feeding behavior also leads them to exploit anthropogenic food sources, which can increase human-bear conflicts. Studies show that bears habituated to human food exhibit altered movement patterns and behaviors compared to wild-feeding counterparts. (Powell et al., 2022.)
Black bears are generally solitary, with overlapping home ranges. Females select bed sites that maximize cover and minimize disturbance, often near food-rich areas. (Mansfield, S. et al., 2022). Males maintain larger ranges, particularly during the breeding season. While typically shy, black bears can become bold when food-conditioned, leading to management challenges. Research highlights that individual variation—rather than species-wide norms—often drives social dynamics, complicating predictions of bear-human interactions. (Stringham, S. et al., 2024.)
Breeding occurs in late spring to early summer, with delayed implantation allowing females to adjust reproduction based on nutritional status. Cubs are born in winter dens, usually in January, and remain with their mothers for about 1.5 years. (Clark, J. et al., 2020.) Litter sizes average two cubs, though reproductive success is strongly tied to food availability. Female philopatry (remaining near natal ranges) contributes to localized population stability, while males disperse more widely.
As seed dispersers and predators of insects and small mammals, black bears play a significant role in forest ecosystems. Their foraging influences plant regeneration and nutrient cycling. They are considered a keystone species in many regions, with cascading effects on biodiversity. (Welfelt, L., 2019.)
Black bears are classified as species of “Least Concern” globally, but regional populations face pressures from habitat fragmentation, hunting, and climate change. Climate-driven shifts in food availability are increasing human-bear encounters, particularly in suburban areas. (Kurth, K. et al., 2024.) Effective management strategies include habitat conservation, public education, and regulation of attractants such as garbage and livestock feed. Prescribed fire and forest restoration are also recommended to maintain diverse food sources. (Weaver, 1999.)
Black bears exemplify adaptability, balancing solitary lifestyles with ecological importance. Their survival depends on habitat quality, food security, and coexistence with humans. Peer-reviewed studies emphasize that conservation must integrate ecological science with proactive management to sustain populations across North America.
Sources: Powell, R. A., Mansfield, S. A., & Rogers, L. L. (2022). Comparison of behaviors of black ears with and without habituation to humans and supplemental research feeding. Journal of Mammalogy.
Welfelt, L., et al. (2019). Black bear distribution and habitat quality. Washington Department of Fish & Wildlife.
Weaver, K. (1999). Black bear ecology and prescribed fire. USDA Forest Service.
Kurth, K. (2024). A systematic review of the effects of climate variability and change on black and brown bear ecology and interactions with humans. Biological Conservation.
Clark, J. et al. (2020). American Black Bear. In Bears of the World. Cambridge University Press.
Mansfield, S. et al., (2020). Bed site selection by female Nort American black bears (Ursus americanus), Journal of Mammalogy.
Stringham, S. et al., (2024). Norms and variance fail to predict butterfly effects on social dynamics by idiosyncratic individuals. Animal Sentience.
Black bears (Ursus americanus) a keystone species, whose ecology and management are deeply shaped by human interactions.
Colorado hosts an estimated 17,000–20,000 black bears, primarily in forested and shrubland habitats of the Western Slope and foothills. Their distribution reflects food availability, cover, and denning sites. Seasonal diets include grasses and forbs in spring, berries and insects in summer, and mast crops in fall. In years of poor natural food production, bears increasingly forage in urban areas, exploiting garbage, fruit trees, and livestock feed. (CPW Digital Collections.)
Colorado’s rapid urban expansion into bear habitat has intensified encounters. Research near Durango found that bears using urban food sources had higher reproductive success but lower survival rates, creating a demographic trade-off. This dynamic complicates management, as food-conditioned bears are more likely to be killed in conflict situations. Public attitudes strongly influence policy, with surveys showing support for coexistence strategies but concern over property damage. (CPW Digital Collections.)
Colorado Parks and Wildlife (CPW) employs a mix of education, attractant regulation, and hunting to manage populations. Peer-reviewed studies emphasize that reducing access to human food is more effective than lethal control in mitigating conflicts. (Lewes, D. et al., 2015.) Innovative approaches, such as buffer zones and community-based attractant management, are being tested to deter habituation. (Willis, 2022.) Population models highlight the species’ slow reproductive rate, meaning overharvest or high mortality can take decades to recover.
Black bears in Colorado remain stable overall, but climate change, urbanization, and human-bear conflicts pose ongoing challenges. Effective management requires integrating ecological science with public engagement, ensuring both population sustainability and community safety.
CPW Digital Collections, accessed Dec. 2, 2025. Black Bear Use of Urban Environments: Testing Management Solutions and Assessing Population Effects.
Lewis, D. et al. (2015). Foraging ecology of black bears in urban environments. Ecosphere.
Willis, T. (2022). Black Bears & Buffer Zones: A novel mitigation strategy. Univ. of Colorado Honors Thesis.
Johnson, H. E., et al. (2018). Black Bear Use of Urban Environments: Testing Management Solutions. CPW.
Miller, S. D. (1990). Population Management of Bears in North America. International Conference on Bear Research and Management.
Colorado, like many states, allows hunters to kill bears each year. Hunters slaughter about 1,500 bears in Colorado each year. Colorado Parks & Wildlife allowed 19,671 permits for hunters to kill bears in 2025.
In addition to the ~1,500 bears killed by hunters each year, ~300 additional bears are killed by CPW, Wildlife Services of Animal Plant Health Inspection Services, and landowners given permits by CPW to kill bears on their property, ostensibly to protect livestock and property, instead of using non-lethal coexistence methods.
Black bears reproduce slowly, having cubs every two to three years. CPW estimates that approximately 17,000-20,000 black bears survive in Colorado, despite the annual hunting, and killing by agencies and landowners.
Hunting is not needed to control bear populations. Human population growth in Colorado (which doubled from 1980 to 2020) has destroyed a lot of bear habitat. Peer-reviewed studies show that human-bear conflict rates are more strongly tied to availability of bears’ natural foods and attractants humans provide to bears, such as unsecured garbage, bird seed, bee hives, uncleaned barbeque grills, and pet food, than to overall bear numbers. (Lewis, D. et al., 2015; Johnson, H. et al., 2018; and Baruch-Mordo, S. et al., 2008).
Lewis, D. L., Baruch-Mordo, S., Wilson, K. R., Breck, S. W., Mao, J. S., & Broderick, J. (2015). Foraging ecology of black bears in urban environments: reliance on human foods increases reproductive output but decreases survival. Ecosphere. Found that bears using urban food sources had higher reproductive success but lower survival, showing that food availability—not population density—drives urban conflict.
Johnson, H. E., Lewis, D. L., Verzuh, T. L., et al. (2018). Human development and climate affect hibernation in a large carnivore with implications for human–bear conflicts. Journal of Applied Ecology. Demonstrated that poor natural food years and urban attractants increase bear activity near people, regardless of hunting pressure.
Baruch-Mordo, S., Breck, S. W., Wilson, K. R., & Theobald, D. M. (2008). Spatiotemporal distribution of human–bear conflicts in Colorado: implications for mitigation. Journal of Wildlife Management. Showed that conflicts spike in low mast years and are concentrated where human attractants are abundant.
Colorado’s black bear population (estimated 17,000–20,000) is stable to increasing. Human-bear conflicts are rising, particularly in urbanizing areas like Durango. Peer-reviewed research demonstrates that conflict frequency is driven primarily by food availability and human attractants, not overall bear numbers. This evidence suggests that non-lethal attractant management is more effective than hunting for reducing conflicts.
Colorado’s black bear conflicts are best addressed through food-focused management strategies rather than increased hunting quotas. Peer-reviewed studies from Durango provide clear evidence that limiting access to human food is more effective at reducing conflicts than hunting. A balanced policy approach—combining regulated hunting with robust attractant management and public education—will sustain bear populations while protecting communities.
In 2024, CPW received 5,022 reports of bear sightings and conflicts, which was 14.8% higher than the previous five years. Unsecured trash continues to be the number-one source of conflicts between humans and bears. (CPW 2024 Bear Report.)
Once a bear enters a town or other human development, her or his likelihood of being killed by an agency or landowner skyrockets. Actions you can take to reduce the killing of bears include:
Rosenbaum M., 2022. Why Bird Feed Can Be a “Gateway Food for Bears.” Audubon Magazine.
Prairie dogs are ecosystem engineers — vital to grassland biodiversity. Historically, over 5 billion prairie dogs inhabited North America, from Canada to Mexico. Today, their range has diminished to just 2% of its original size, and two of five species are now threatened or endangered.
Provide food and shelter for species such as black-footed ferrets, burrowing owls, mountain plovers, swift foxes, and ferruginous hawks. Their burrowing improves soil aeration, vegetation diversity, and water absorption.
Historical Context:
Seen as pests by early settlers, prairie dogs were mass-killed through poisoning and recreational shooting — a practice that persists today. Modern research shows prairie dogs benefit ranchers and livestock by promoting healthy rangelands.
Current Threats:
Unlimited Killing on Public Lands, Real Estate Development, destroying habitats and colonies
Hoogland, J.L. (2006). Conservation of the Black-tailed Prairie Dog: Saving North America’s Western Grasslands. Island Press. Kotliar, N.B. & Plumb, G. (1999). A critical review of assumptions about the prairie dog as a keystone species. Environmental Management 24(2):177-192.
Miller, B. et al. (2000). The role of prairie dogs as a keystone species: response to Stapp. Conservation Biology 14(1):318-321. Miller, B.J. et al. (2007). Prairie dogs: an ecological review and current biopolitics. Journal of Wildlife Management 71:2801-2810.
Chronic Wasting Disease (CWD): A fatal neurological illness affecting deer, elk, and moose populations, threatening both wildlife health and ecosystem stability.
Key challenge: lead Poisoning from Ammunition: Birds feeding on carcasses left by hunters ingest lead fragments, leading to illness and death. Non-lead ammunition alternatives are essential for conservation.