Biodiversity

Unlike native grazers like elk, bighorn sheep, deer and bison, which disperse and wander great distances, nonnative cattle mostly concentrate near waterways for long periods of time, grazing on grasses and trampling on most vegetation. Overgrazing also reduces the height and ground cover of grasses, removing bird’s refuges from predators and favorable habitats for roosting and nesting. This loss of grasses and shrubs eliminates important cover for deer, antelope fawns and elk calves, as well as amphibians, sage grouse and other birds who use riparian areas for nesting. 

Meanwhile studies have shown removing livestock helped with restoration of riparian tree species. Cattle are a non-native species that didn’t evolve in the landscapes of the American West. They have very different grazing and behavioral patterns from native bison and cannot serve as a natural replacement grazer to the ecosystems that were once home to bison. 

Today many wild species — including the desert tortoise, Sonoran pronghorn, sharp-tailed grouse, bison, bighorn sheep, deer and elk — face competition with domestic cattle over water, land and vegetation. Meanwhile forest ecosystems are consumed by livestock, leaving little residual cover or food for native wildlife. Cattle, sheep and goats consume the vast majority of all U.S. wild vegetation. In the Greater Yellowstone Ecosystem, 90% of the forage on public lands is allotted to domestic livestock, even though this region also has the greatest concentration of native, wild herbivores left in the country and is the last substantial, nearly intact ancient ecosystem in the United States. 

Wild plants are essential components of natural ecosystems. Native plants harvest the energy of the sun via photosynthesis and provide both food and diverse habitat for other native wildlife, including insects, pollinators, birds and larger animals. This vegetation improves the ability of soil to store water and effectively reduces flooding and runoff. 

But wild plants are also vital to agroecological food systems. Wild crops can increase systemic food security, agricultural integrity and environmental health. Deforestation is a leading cause of many population losses of wild relatives of fruit, nuts and other industrial crops like tomatoes, squash and corn. Wild relatives of cereal crops in arid landscapes are especially harmed by overgrazing and desertification. Yet more than ⅕ of wild plant species are threatened, and overgrazing is a major contributor to this problem. 

Grasslands are among the country’s most degraded habitats. In recent years, the Great Plains of the United States and Canada have seen an annual conversion rate of more than 2 million acres with 53 million wild acres lost to agricultural expansion since 2009. Converting grasslands can decrease half the carbon sunk in the surface of the soil. Many so-called native grasslands were actually  forests or woody savannas in recent history, home to more wildlife and carbon  storage. 42% of global grasslands, a significant share used as pastureland, used to be  forests and if we can return the original forests on that land, the carbon  storage would increase by 265 GtC from its present value.

Drylands are also affected by livestock, and grazing is a leading cause of species endangerment in arid western areas. Cattle grazing is a leading factor in dead soil, where soil dries and erodes and vital soil becomes dust. When livestock graze vegetation to the roots, plants grow short, unsustainable roots and eventually stop growing, leaving areas with no vegetation. Where the soil is exposed to the elements, it dries and becomes dirt. More than 8.4 billion acres are grazed globally, 73% of which are degraded, with 24 billion tons of fertile land lost annually, particularly in arid landscapes like the American West, with fragile ecosystems that did not evolve with non-native cattle.  

Wildlife Spotlight: American Bison

Wild bison roam less than 1% of their historic North American range, driven to the brink of extinction in this region by slaughter and habitat destruction in the 19th century. The vast majority of their range is now used by the meat industry or for urban development. Today bison are threatened from genetic contamination by cattle and disease, domestication, habitat destruction and federal herd-management programs. In Yellowstone National Park, bison that stray outside the boundaries are often culled by the National Park Service at the behest of the livestock industry for fear of infecting cattle with brucellosis, even though there isn’t a single documented historical case of bison transmitting this disease to cattle. Yet the U.S. Fish and Wildlife Service refuses to protect bison under the Endangered Species Act. Better solutions to the commercial interests of cattle grazers are paramount to protecting wildlife like bison.  

Often overlooked harms from grazing include direct killings at the behest of or by cattle and sheep operators. Species are killed en masse including wolves, coyotes and also prairie dogs, who are regularly poisoned by the livestock industry. Similarly, grasshoppers are poisoned even on public lands because they eat grass, which the industry appropriates for livestock. Fewer grasshoppers mean less food for birds, rodents, fish and other species. The loss of prairie dogs, ground squirrels, grasshoppers and other native species has negative consequences up the food chain. 

Grazing impacts vary by region, soil and climate but also by a region’s evolutionary history. The evolution of a natural habitat alongside large, hoofed mammals that exert pressures on native plants and ecosystems can determine which areas have greater resilience to livestock grazing. Although not all large, hoofed mammals are the same — native wild bison are not cattle for example, and behave differently on the landscapes — there is significant variance in cattle grazing impacts east and west of the Rockies, for this reason. 

Cattle grazing removes grasses, allowing tree seedlings to become established, leading to greater tree densities. Grazing also leads to the spread of invasives like cheatgrass — a highly flammable annual grass that increases fire frequency, negatively affecting native grasses and shrubs.   

Grazing hurts migratory birds and changes the ecological balance of their natural habitats. According to the North American Breeding Bird Survey, grassland birds are undergoing more widespread declines than any other bird group. Meanwhile so-called “cowbirds” that follow herds of cattle, and lay their eggs in the nests of other birds, have increased dramatically as a result of the expansion of cattle grazing. Cowbirds have caused declines in populations of other birds, such as southwestern willow flycatchers, in areas where cowbirds were once uncommon. 

Livestock compact and trample soils, reducing filtration, creating higher runoff and more flooding and erosion. Cattle destroy biocrusts that bind soils and capture beneficial free nitrogen. Damaged soil harms the food chain from the bottom up, making it harder to support plant life that provides food and habitat for myriad other species. Trampling of riparian areas negatively affects 75%-80% of the West’s wildlife species.

The slaughter of wildlife at the behest of the meat and dairy industry is notoriously ineffective. Not only does it fail to stop predation — indiscriminate traps and poisons kill threatened and endangered species they’re not aimed at, from eagles and condors to wolves and black-footed ferrets. They’ve even harmed children and domestic pets. Wildlife Services has used reckless methods often found in violation of National Environmental Policy Act regulations that are often environmentally toxic, which disrupt biological diverse systems and reduce the ecological integrity of the landscape.

Wildlife Spotlight:  Black-Footed Ferret

One of the most endangered mammals in North America, the black-footed ferret once numbered more than 5 million in population, roaming the grasslands and basins from southern Canada to Texas. There are now 340 wild ferrets on the brink of extinction. In addition to urban development and habitat loss from oil pipelines, one of the reasons this species faces extinction is that it has been targeted by Wildlife Services, and its primary food, prairie dogs, have been aggressively slaughtered by the meat industry. 

One major impact of high-density cattle grazing is the loss of vegetative cover. Poorly managed cattle grazing leads to overgrazing too frequently in the same areas, trampling, or grazing the plants too close to the soil. As cattle graze plants to the crust, this weakens root systems and exposes and compacts the soil. By degrading soil quality, cattle increase soil erosion and — combined with nutrient losses from pastures — can pollute surface and subsurface waters. 

Recent studies show significant impacts on Western watersheds from cattle grazing and supplemental feed crop irrigation and forage production like hay, draining waterways like the Colorado River that dozens of fish, birds and other species depend on. Irrigation of cattle-feed crops is the greatest consumer of western rivers, and beef and dairy consumption are the leading drivers of water shortages and fish imperilment in the West.