5.5 million bees discovered living beneath New York cemetery for over a century

A morning commute through East Lawn Cemetery in Ithaca, New York led to an extraordinary discovery. In spring 2022, Rachel Fordyce, a laboratory technician at Cornell University's entomology department, noticed unusual insect activity on her walk to work. She collected specimens and showed them to Bryan Danforth, an entomologist at the university.

Analysis identified the insects as Andrena regularis, known as mining bees or miner bees. Unlike honeybees that live in colonies, this species is solitary and digs tunnels in soil to nest. Historical records show the insects have occupied the cemetery, founded in 1878, since at least the early 1900s.

Cornell researchers published their findings in April in the journal Apidologie. They documented one of the largest aggregations of underground bees ever recorded globally. The population spans roughly 1.25 acres and is essential for pollinating orchards in the region. The estimated 5.5 million bees equal the population of more than 200 domestic honeyhives.

Scientists used 10 traps placed across the cemetery between late March and mid-May 2023 to count the colony. Each trap covered less than one square meter of soil and funneled insects emerging from the ground into glass containers. The traps captured more than 3,000 insects representing 16 different species, including bees, beetles, and flies. Andrena regularis dominated the sample. Using these numbers, researchers calculated the total population at between 3 and 8 million insects, with an average of 5.5 million.

The research revealed new details about this poorly understood species. Male bees emerge from the soil a few days before females in early April, maximizing mating chances. Females then dig nests and lay eggs in underground cells filled with pollen and nectar. The bees spend winter as adults underground, allowing them to wake early in spring when apple trees in nearby Cornell orchards begin flowering. Scientists also documented parasitism by bees from the Nomada imbricata species, which lay their eggs in miner bee nests, destroying the host larvae.

The discovery emphasizes protecting underground bee habitats. Roughly 75 percent of wild bees are solitary species living in soil. Historic city cemeteries offer ideal conditions: sandy soil easy to dig, no pesticides, and freedom from intensive agriculture or development. To prevent accidental destruction from construction or road work, the study authors launched a citizen science program. The project asks the public to report underground bee aggregations, helping scientists survey and protect these pollinators before habitat loss threatens their survival.