Notice the bright yellow under the abdomen of this bee—that’s pollen, and females of this species carry it back to their nests this way. This pollen almost certainly came from one of two species of mint plants that live, like the imperiled blue calamintha bee, in Florida’s dwindling scrub regions, and on which the bees rely.

The host mint plants are very rare, putting pressure on the blue calamintha bees. In 2015, conservationists petitioned the U.S. Fish and Wildlife Service to add the bees to the federal endangered species list, which would provide the species with protection, but so far that hasn’t happened. And while it’s hard to say for certain, since insect populations often fluctuate from year to year, researchers estimate the numbers of these rare blue bees may have dropped by as much as 90 percent.