The Blue Calamintha Bee: Habitat preferences of a narrow endemic.

Many populations of native pollinators, particularly specialists, are declining due to environmental stressors. The Blue Calamintha Bee, Osmia calaminthae, is a specialist bee native to only four sites, all in Highlands County, Florida, USA on the Lake Wales Ridge. The bee is a candidate for federal listing. The Blue Calamintha Bee specializes on the endemic woody mint, Ashe's Calamint, Calamintha ashei, but little else is known about its habitat requirements. In a pilot study, we attempted to characterize the habitat preferences of the bee through observation at three different properties where it had been observed in the past. We spent 18 hours conducting pollinator observations and line-transect surveys during the mint's peak bloom period, April-May 2016. The bee was observed at the two study sites with lower shrub cover, but not at a third site with higher shrub cover. Therefore, the bee may prefer open foraging areas. Additionally, honeybees were the most active flower visitor of Ashe's Calamint at all three sites, indicating the potential for interference with the Blue Calamintha Bee. Our results indicate that land managers should use periodic fire to control cover of larger shrubs and retain cover of Ashe's Calamint. [ABSTRACT FROM AUTHOR]