Recent research from the University of Guelph highlights a promising path for supporting wild bee populations amid ongoing pollinator declines. The study, published in the open-access journal FACETS on April 8, 2026, examines how different grassland types and management strategies influence bee diversity in southern Ontario's agricultural landscapes. Titled "Grassland management and wild bee biodiversity: conservation lessons from native and non-native systems in southern Ontario," it synthesizes global and local evidence to offer practical guidance for landowners and policymakers.
Wild bees play a vital role in pollinating crops and wild plants, contributing to an estimated $267–$657 billion in global economic value annually. In Canada, approximately 460 bee species exist in Ontario alone, but habitat loss from agricultural intensification has reduced native grasslands to just 1%–3% of their historical extent—roughly 1,000 km² originally. Pastures, often dominated by non-native species, have also declined by 37.2% between 2011 and 2021, dropping from 661,081 hectares to 415,549 hectares. This fragmentation threatens grassland-associated bees, including three of Ontario's four declining bumble bee species.
Understanding Southern Ontario's Grassland Landscape
Southern Ontario's grasslands encompass a mix of remnant tallgrass prairies, oak savannas, restored habitats, and extensive non-native pastures used for livestock grazing. Native systems feature diverse forbs and grasses that provide essential nectar, pollen, and nesting sites for specialist bees. In contrast, non-native pastures, typically sown with exotic cool-season grasses like Kentucky bluegrass (Poa pratensis) or timothy (Phleum pratense), offer fewer floral resources but cover vast areas suitable for management interventions.
Historical conversion to row crops and urban development has left scattered remnants, but programs like the Alternative Land Use Services (ALUS) have enrolled over 17,202 hectares in pollinator-friendly habitats. These initiatives demonstrate how working lands can bridge gaps in bee conservation, particularly where large-scale native restoration is challenging.
Native vs. Non-Native Grasslands: Bee Diversity Compared
The review reveals clear differences in bee communities between native and non-native grasslands. Native tallgrass prairies and oak savannas support higher species richness and abundance, particularly for bumble bees. For instance, studies in northern Illinois—analogous to Ontario conditions—found bumble bee numbers 1.75 to 3.5 times higher in native prairies than exotic pastures. Ungrazed native sites recorded the highest abundances, averaging 325–357 bees per site, compared to 223–249 in grazed native and 136–236 in grazed non-native plots.
Yet non-native systems are not without value. One Ontario survey of rotationally grazed pastures identified 264 species and over 39,000 individuals—the largest such dataset in the province—showing they can harbor diverse communities, including 23 species unique to non-native plots. Red clover-dominated fields supported more than twice as many bumble bees as flower strips, underscoring the potential of targeted forage enhancements.
Grazing Practices: Balancing Livestock and Pollinators
Grazing management emerges as a critical lever for bee support. Moderate or rotational grazing boosts floral diversity by promoting perennial forbs over annual weeds, increasing herbaceous cover by 19% and reducing invasives by 14%. This extends bloom periods, providing steady resources. Delaying grazing until after peak flowering—e.g., mid-July for many forbs—can significantly enhance bumble bee richness.
Overgrazing, however, harms nesting sites and tramples vegetation, slashing bee numbers; intensively grazed sites had only 4.7 species versus 11.5 in ungrazed ones. Adaptive strategies like mob grazing or rest-rotation mimic natural disturbances, improving soil health (+20.6% carbon) and bee habitats. Farmers adopting these see premiums for "bee-friendly beef," up to $1.06 per pound in U.S. analogs.
Photo by Vasilis Caravitis on Unsplash
Restoration Success Stories and Small-Scale Wins
Restoration amplifies benefits. Converting just 10% of farm area to native prairie mixes doubled bee species richness and boosted abundance by 72% in trials. Even non-native pastures respond to seeding with legumes like alsike clover (Trifolium hybridum), rivaling native diversity. In southern Ontario, remnant prairies yielded 142 species, while pastures hit 264, illustrating complementary roles.
Local efforts at Brock University and Glenridge Quarry naturalizing areas captured 124 species, emphasizing edge habitats' value. These scalable interventions align with Canada's 2030 Nature Strategy, aiming to halt biodiversity loss through habitat protection.
Ontario's Conservation Programs: Incentives for Change
Ontario leads with farmer-centric programs. ALUS credits landowners for ecosystem services, funding pollinator habitats across 17,202 ha and enhancing arthropod diversity. The Grasslands Stewardship Initiative promotes native seed mixes and grazing plans. SARPAL targets at-risk species like the rusty patched bumble bee (Bombus affinis), extirpated since 2009.
These yield co-benefits: improved soil, water quality, and carbon sequestration. Nationally, similar efforts could create 1.86 million ha of habitat from 10% pasture enhancement. For context, protecting 11.6%–16.7% of land as bee habitat aligns with expert recommendations, far exceeding current baselines.Read the full FACETS study
University of Guelph's Role in Bee Research
Lead author Kyr Lightburn and co-author Ralph C. Martin from the University of Guelph's Department of Plant Agriculture anchor this work. Guelph's expertise in sustainable agriculture informs practical recommendations, building on prior surveys like Lightburn's 39,000-specimen pasture study—the province's largest. The university's regenerative farming initiatives complement findings, training future ecologists and farmers.
Guelph researchers emphasize interdisciplinary approaches, linking entomology, agronomy, and policy for real-world impact. Their efforts support Ontario's greenbelt protections and pollinator health strategies.
Agricultural Implications: Profitable Pollinator-Friendly Farming
Bees boost yields for crops like alfalfa, clover, and fruits—up to 35% of production. In Ontario, pasturelands (415,000+ ha) offer untapped potential. Rotational grazing not only sustains bees but enhances beef quality and farm resilience. Incentive programs provide payments ($50–$200/ha), making conservation economically viable.
Challenges include pesticide drift and monocultures, but buffer strips and no-till practices mitigate risks. U.S. models show bee-friendly labels command premiums, suggesting Ontario farmers could gain similarly.
Photo by Wolfgang Hasselmann on Unsplash
Future Outlook and Research Gaps
While encouraging, gaps persist: long-term data on management-bee links, climate impacts, and pesticide synergies. The study calls for expanded monitoring, like blue vane traps across sites, and trials on non-native enhancements. Ontario's 2030 targets demand scaled action, potentially via national pollinator strategies.
Optimism lies in farmer adoption; surveys show willingness for practices yielding dual livestock-pollinator benefits. Collaborative research from institutions like Guelph will guide this transition.Explore Tallgrass Ontario pollinator resources
| Grassland Type | Bee Abundance (per site) | Species Richness |
|---|---|---|
| Ungrazed Native | 325–357 | High |
| Grazed Native | 223–249 | Moderate-High |
| Grazed Non-Native | 136–236 | Moderate |
Actionable Insights for Landowners and Policymakers
- Implement rotational grazing with post-bloom delays to maximize floral resources.
- Seed non-native pastures with bee-friendly forbs like clover or birdsfoot trefoil.
- Enroll in ALUS or similar for financial support and expertise.
- Monitor with simple traps; aim for diverse blooms April–October.
- Reduce pesticides near habitats; prioritize IPM (integrated pest management).
These steps foster resilient agroecosystems, securing pollination services worth millions regionally.