What Are Ground Nesting Bees — and Why Were 5.5 Million of Them Found Under a Cemetery?
One of the largest and oldest recorded aggregations of ground-nesting bees in the world was hiding beneath a small cemetery in upstate New York. Nobody knew until a lab technician stopped to look.
A new Cornell University study published April 13 in the journal Apidologie estimates roughly 5.5 million bees are nesting underground at East Lawn Cemetery in Ithaca, N.Y.
The finding reveals how abundant these overlooked native pollinators are — and, according to researchers, how urgently their nesting sites need protection.
How Cornell Researchers Counted Millions of Bees Underground
The discovery began with a walk. Rachel Fordyce, a technician at a Cornell University entomology lab, noticed an unusual number of bees while passing through the 1.5-acre cemetery.
Rather than avoiding them, she captured some in a jar and brought them to Bryan Danforth, a professor of entomology in the College of Agriculture and Life Sciences.
They identified the specimens as Andrena regularis, commonly called the regular mining bee.
To estimate the population, the research team — led by Steve Hoge — deployed emergence traps, small mesh tents covering less than a square meter of ground. Each trap includes a funnel directing insects into a glass collection jar.
The researchers set up 10 traps between March 30 and May 16, 2023.
The traps collected 3,251 specimens representing 16 species, including bees, flies and beetles. A. regularis was the most abundant species captured. Researchers determined the average number of bees emerging per square meter and scaled that figure across the cemetery’s approximately 6,000 square meters.
Population estimates ranged between 3 million and 8 million bees. The average calculation settled at 5.5 million.
“I was completely floored when we did the calculations,” Danforth told Scientific American.
“I have seen published estimates of bee aggregations in the hundreds of thousands. But I never really imagined that it would be 5.56 million bees,” Danforth added.
Hoge said there might be other larger aggregations that have yet to be identified, but this was one of the largest ever recorded in literature.
Why Ground Nesting Bees Thrive in Cemeteries
Roughly 75% of all bee species are solitary ground nesters. Unlike honey bees, they nest in underground tunnels rather than hives. They are non-aggressive, beneficial for soil aeration and rarely sting.
Cemeteries make particularly good habitat because they offer quiet environments with minimal ground disturbance and typically lack pesticide use.
East Lawn Cemetery, established in 1878, was especially well-suited because of its proximity to Cornell Orchards, approximately one-third of a mile away. The orchards provide a large resource of blooming flowers in early spring.
A. regularis typically emerges around April in New York when midday temperatures consistently reach 70 degrees. Their emergence aligns with apple bloom and other fruit trees plus early wildflowers.
Records of A. regularis specimens collected at the site stretch back to the early 1900s, though the most thorough prior source on the species was from 1978.
The new study introduced a fresh methodology for researching these bees, which are vastly understudied.
What This Discovery Means for Pollinator Conservation
The findings carry a clear warning. If ground-nesting bee habitats are paved over or disturbed, millions of important pollinators could disappear.
“The research elevates the value of solitary ground-nesting bees and shows just how abundant these bees are, how important they are as crop pollinators, and that we need to be aware of these nest sites and preserve them,” Danforth told the Cornell Chronicle.
“These populations [of ground-nesting bees] are huge, and they need protection,” Danforth added. “If we don’t preserve nest sites and someone paves over them, we could lose—in an instant—5.5 million bees that are important pollinators.”
This article was created by content specialists using various tools, including AI.
