TUCSON, Ariz.— The Center for Biological Diversity has sued the U.S. Fish and Wildlife Service for failing to make decisions on protecting four imperiled bee species under the Endangered Species Act.

The lawsuit, filed Monday in federal court in Tucson, Arizona, seeks determinations on petitions filed by conservation groups to protect American bumblebees, Southern Plains bumblebees, variable cuckoo bumblebees and blue calamintha bees.

“America’s bumblebees are in deep trouble, and it’s critical for the U.S. Fish and Wildlife Service to stop their plunge toward extinction,” said Jess Tyler, the Center scientist who authored the bumblebee petitions. “The decline of native bees across the U.S. is a preventable tragedy. We still have time to save these life-bringing pollinators.”

Native bees are crucial pollinators of wild plants and crops. Some plants have such specialized relationships with bees that their life cycle depends on being pollinated by certain bee species. The loss of these pollinators would be catastrophic for agriculture and the environment, since 75% of food crops and 90% of wild, flowering plants rely on animal pollination.

A Center investigation found that the majority of America’s native bee species are in decline, with nearly one-quarter at risk of extinction. Native bees suffer from habitat loss, pesticide use, disease, climate chaos and competition from nonnative bees. As a result, even adaptable habitat generalists like American bumblebees are suffering from collapsing populations.

Following petitions by the Center and allies to protect American bumblebees, Southern Plains bumblebees, variable cuckoo bumblebees and blue calamintha bees under the Endangered Species Act, the Fish and Wildlife Service found that the bees may warrant protection. But the agency has failed to make the required determination for endangered species protection.

Information on how to help native pollinators in your own backyard is available at the Center’s Native Pollinator Gardening Guide.

Species Background

American bumblebees — Once among the most common and widespread bumblebees, American bumblebees were found in open areas across all of the lower 48 states except Washington. After a severe decline starting in the 2000s, this iconic bumblebee has disappeared from at least eight states and experienced severe declines across its remaining range. Habitat loss, pesticide contamination, disease spillover from domesticated bee colonies and other threats have accelerated its decline.

Southern Plains bumblebees — These bumblebees are native to the perennial grasslands and open woodlands of America’s Great Plains, Midwest and southeastern coastal plains. As their habitats have degraded and disappeared, they’ve become twice as rare relative to other bees in recent decades and have vanished altogether from six states.

Variable cuckoo bumblebees — Among the rarest bumblebees in North America, with zero confirmed observations since 1999, these cuckoo bumblebees have a fascinating life cycle that requires them to invade the nests of American bumblebees. That ties its fate to a host species in precipitous decline, demonstrating the ripple effects of the loss of a single species.

Blue calamintha bees — These metallic blue mason bees rely entirely on two rare flowers found in central Florida’s fragile sand pine scrub ecosystems. Habitat loss to agricultural, commercial and residential development are existential threats to this highly restricted bee. Other threats include pesticides, disease and natural disasters.