All the Buzz: How Native Bees Are Being Bulldozed by Livestock
Native bees are keystone species in arid public lands ecosystems. Livestock grazing is pushing many of them to the brink.
Bees don’t just make honey. They make ecosystems possible by pollinating flowering plants. And in the arid West—where life clings to harsh conditions and ecological relationships are tight-knit—native bees are indispensable.
At this year’s Healthy Public Lands Conference, Mary O’Brien of Project Eleven Hundred delivered a striking reminder of just how critical—and imperiled—these species are. The numbers she shared were staggering. The United States is home to roughly 4,000 species of native bees—from metallic green sweat bees and solitary digger bees to the charismatic bumble bees that hum through high mountain meadows (Xerces Society, 2024). Around 1,600 species are found in California, 1,300 in Arizona, and over 1,100 in Utah. Together, these three arid Western states support well over a quarter of all native bee species found in the U.S.—and much of that diversity depends on public lands.
This biodiversity isn’t just impressive—it’s fragile. It depends on intact habitat, abundant wildflowers, and nesting areas free from disturbance. It’s hindered by pesticide use. In places like Grand Staircase-Escalante National Monument, scientists have documented over 650 native bee species in a single protected region. These are strongholds.
Livestock grazing on public lands remains one of the most direct and devastating threats to pollinator habitat in the West. Cows and sheep eat the tops of flowering plants—the very blooms bees need to survive. They trample fragile ground nests. They compact soil, disrupt plant communities, and erase the seasonal floral diversity native bees require (Kearns & Oliveras, 2009; Rhoades et al., 2018).
Some may ask: Don’t elk, deer, or bison do the same? The answer is no—at least not at the scale or intensity of domestic livestock. Native wild ungulates move with seasonal patterns, rarely linger in concentrated herds for extended periods, and are part of the ecosystems they evolved within. Their grazing behavior tends to be more dispersed, less destructive, and often supports plant diversity through moderate disturbance. In contrast, livestock are managed in dense numbers, often held in place by fencing, and graze repeatedly on the same lands without the same ecological feedback loops.
This isn’t just theory—it’s well-documented. A study by Kearns and Oliveras (2009) found that cattle grazing significantly reduced both native bee abundance and the availability of floral resources in mountain meadows. Ground-nesting bees, which make up about 75% of native species, are especially vulnerable to soil compaction and trampling. And research by Rhoades et al. (2018) found that livestock grazing filters bee communities in ways that reduce their functional diversity—eliminating specialists and favoring a narrow set of traits.
Most native bees are solitary—each female builds and provisions her own nest. Many are specialists, tied to just one plant species or family. If those plants disappear, so do the bees. Cane and Tepedino (2001) emphasized that honey bees, often used in agriculture, cannot replace these wild pollinators. Specialist bees evolved with rare native flora and are uniquely equipped to pollinate them. Some rare wildflowers depend on a single species of wild bee for all of their pollination, and if that bee species is eliminated, the flower would go extinct for lack for seed production. When grazing diminishes plant diversity, the entire mutualistic system collapses.
And yet, one species is often treated as a stand-in for the entire bee kingdom: the non-native European honey bee. While important for agricultural crop pollination, European honeybees are not native to North America—theyi was brought here by colonists in the 1600s. Today, it’s managed like livestock. Just one species among thousands, it can’t replicate the ecological roles of the diverse native bees it often displaces. In fact, managed honey bees compete for floral resources, spread disease, and may fail to pollinate the very plants that many native species co-evolved with (Cane & Tepedino, 2001; Xerces Society, 2019). Relying on honey bees as proxies for pollinator health is like pointing to feedlot cattle as evidence of wildlife conservation.
Even federal land managers know this is a problem. In Utah’s Southern Monroe Mountain grazing plan, the Final Environmental Impact Statement listed pollinator habitat degradation as one of five “significant issues.” The analysis identified indicators like nectar and pollen abundance, nesting conditions, and landscape-scale habitat connectivity. Seventeen pages of analysis laid out the damage—but the grazing permits remained unchanged. The bees lost (USFS, 2021).
The Xerces Society has urged that any grazing on public lands be managed with pollinators in mind, offering guidance to limit overlap with blooming periods, protect nesting areas, and reduce floral competition from honey bees (Xerces Society, 2019). But most public lands policies remain stuck in the past, focused on livestock productivity instead of ecological integrity.
Mary O’Brien’s message was clear: native bees are not background noise. They are foundational. And they are fascinating. From fairy bees the size of a grain of rice to bumble bees that buzz like small engines, these creatures are the engine of wildland resilience. If we lose them, we lose the West.
References
Cane, J.H. & Tepedino, V.J. (2001). Causes and extent of declines among native North American invertebrate pollinators: Detection, evidence, and consequences. Conservation Ecology, 5(1), 1. https://www.ecologyandsociety.org/vol5/iss1/art1/
Kearns, C.A. & Oliveras, D.M. (2009). Environmental factors affecting bee diversity in urban and remote grassland plots in Boulder, Colorado. Biodiversity and Conservation, 18(3), 837–856. https://doi.org/10.1007/s10531-008-9502-3
Rhoades, P.R. et al. (2018). Grazing and climate effects on pollinator abundance and diversity in semi-arid grasslands. Ecological Applications, 28(7), 1667–1678. https://doi.org/10.1002/eap.1769
USFS (2021). Final Environmental Impact Statement for the Southern Monroe Mountain Allotments Livestock Grazing Authorization. Fishlake National Forest.
Xerces Society (2019). Grazing and Pollinators: A Best Practices Guide. https://xerces.org/publications/guidelines/grazing-and-pollinators
Xerces Society (2024). Pollinator Conservation – Native Bees. https://xerces.org/pollinator-conservation/native-bees
Grace Kuhn is the Digital Director for Western Watersheds Project. grace@westernwatersheds.org