Millions of Bees Have Thrived Under a New York Cemetery for More Than a Century

morning walk A massive colony of approximately 5.5 million underground bees was discovered through the East Lawn Cemetery in Ithaca, New York. The discovery, which a Cornell University research team published in April in the journal EpidologyDocuments one of the largest aggregations of these insects ever recorded in the world. related to population, species andrena regularisCovering approximately 1.25 acres and important for pollination of area gardens, it shows that historic cemeteries can prove unexpected refuges for urban biodiversity.

Origin of discovery

It all started in the spring of 2022, when Rachel Fordyce, a laboratory technician in Cornell University’s entomology department, noticed an unusual appearance of insects while on her way to work. After collecting some specimens, he showed them to entomologist Brian Danforth of the same university. The analysis showed that they were andrena regularisWhich is commonly called mining or miner bee. Unlike honey bees, this wild species leads a solitary lifestyle and nests by digging tunnels in the ground. Historical records show that this pest has been present in the cemetery, established in 1878, since at least the early 1900s.

census

To calculate the colony size, scientists set 10 traps in a cemetery between late March and mid-May 2023. These tiny mesh curtains cover less than a square meter of soil and ground-breaking insects in a glass container. In total, more than 3,000 insects from 16 different species were sampled, including bees, beetles and flies, with extreme abundance. andrena regularis. Based on the average density found in the traps, researchers estimated the total population to be between 3 and 8 million, with an average value of 5.5 million – the equivalent of more than 200 domestic beehives.

The research yielded previously unpublished data on the biology of this little-studied insect. Traps revealed that males emerge from the ground a few days earlier than females during the first warm days of April, a strategy that maximizes mating opportunities. Next, females dig nests and lay eggs in cells filled with pollen and nectar. This species has the distinction of overwintering underground in the adult stage, which allows it to become active very early in the spring, in perfect synchrony with the flowering of the apple trees in the orchards of nearby Cornell University. Monitoring also revealed the presence of complex ecological dynamics, such as parasitism by bees. Nomada imbricata Species that lay their eggs in the nests of the host species at the expense of the parent larvae.

A legacy to preserve

The discovery highlights the need to protect the nesting sites of wild bees, 75 percent of which are solitary species living underground. Places such as old city cemeteries offer ideal conditions: sandy soil that is easy to dig, no pesticides, and an environment that is not subject to the changes typical of intensive agriculture or housing development. To prevent a population of this magnitude from being accidentally destroyed by concrete pouring or road work, the study authors have launched a global citizen science initiative. The project invites citizens to report the presence of underground bee aggregations so that these important pollinators can be surveyed and protected before habitat fragmentation threatens their survival.

This story originally appeared on WIRED Italia and is translated from Italian.