A remarkable discovery at East Lawn Cemetery, Ithaca, New York, has revealed a subterranean bee colony of 5.5 million Andrena regularis bees. This vast population, established since the early 1900s, plays a crucial role in pollinating local orchards, underscoring the potential for historic cemeteries to be unexpected havens for urban biodiversity.

The genesis of the discovery began when Rachel Fordyce noticed an unusual presence of insects during her morning walk. Analysis with Bryan Danforth identified them as Andrena regularis, solitary bees known for their underground nesting habits. Scientists employed traps to estimate the colony size, extrapolating from 3,000 sampled insects to a total population ranging between 3 and 8 million.

Further insights into the species’ lifecycle were gained through monitoring, revealing early emergence strategies that maximize mating opportunities and the earliest spring activity in sync with apple tree flowering. The research also highlighted complex ecological dynamics, including parasitism by Nomada imbricata bees.

The findings emphasize the importance of protecting underground bee nesting sites, 75% of which are solitary species like Andrena regularis. Old city cemeteries offer ideal conditions due to sandy soils and a pesticide-free environment. A global citizen science initiative has been launched to survey and protect these vital pollinators.