ITHACA — Researchers documented an aggregation of approximately 5.5 million solitary Andrena regularis bees within a 1.5-acre area at East Lawn Cemetery in Ithaca, New York. The findings were published on April 13, 2026, in the journal Apidologie.

The bee aggregation, estimated to range between 3 million and 8 million individuals, is comparable in size to more than 200 honeybee hives. Andrena regularis, commonly known as the regular mining bee, is a solitary wild bee species that nests underground and plays a key role in pollinating crops and wild plants.

Rachel Fordyce, a lab technician at Cornell University, first noticed the unusually high concentration of bees during a spring 2022 walk through the cemetery and collected specimens to show entomology professor Bryan Danforth. She said in a podcast interview, "These are all over the cemetery."

Steve Hoge, an undergraduate researcher and lead author of the study, said the site may represent one of the largest known bee aggregations documented in scientific literature. "I'm sure there are other large bee aggregations that exist around the world that we just haven't identified, but in terms of what is in the literature, this is one of the largest," Hoge said.

Researchers placed 10 emergence traps—small mesh tents covering less than one square meter of ground—throughout the cemetery between March 30 and May 16, 2023. The traps collected 3,251 insects from 16 species, with Andrena regularis overwhelmingly dominant. The species prefers sandy soil, which East Lawn Cemetery contains in abundance, and typically emerges in April when temperatures reach around 70 degrees Fahrenheit.

"This species overwinters as adults, which is relatively rare, and that's part of the reason why they come up out of the ground so early in the spring, timed to the apple bloom," Hoge explained. "The males come out first and wait for the females, so that they have the best opportunities to mate and pass on their genes," he added.

Danforth emphasized the ecological importance of the discovery. "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," he said. He warned that losing such sites to development could instantly eliminate millions of vital pollinators: "These populations are huge, and they need protection. 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."

The study noted that cemeteries offer ideal bee habitat due to minimal disturbance and absence of pesticides. Historical records indicate Andrena regularis has inhabited East Lawn Cemetery since at least the early 1900s. Danforth and colleagues have since launched a global citizen science initiative to locate and protect similar ground-nesting bee aggregations.