Chasing a little-known fairy bee (Perdita meconis) in a dynamic desert landscape

Authors: CHANPRAME, SARIT - Utah State University; MEIDT, COLLEEN - Utah State University; Griswold, Terry; WILSON, JOSEPH - Utah State University; Graham, Kelsey

Submitted to: Insects
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/7/2024
Publication Date: 11/14/2024
Citation: Chanprame, S., Meidt, C., Griswold, T.L., Wilson, J.S., Graham, K.K. 2024. Chasing a little-known fairy bee (Perdita meconis) in a dynamic desert landscape. Insects. https://doi.org/10.3390/insects15110892.
DOI: https://doi.org/10.3390/insects15110892

Interpretive Summary: There are worries that bees are not doing well. This has led to efforts to protect them. But these efforts are made difficult because we know so little about the lives of most bees, where are they found, where they make their nests and what kinds of flowers they use to collect pollen. The Mojave Poppy Bee, a kind of fairy bee, is one of these bees that we don’t know much about, but it has been suggested that it is not doing well. This study was designed to learn how big is the area they live in and whether they were particular about the flowers they visit. We found that this bee is still around in a number of places where it was found in the past. The interesting thing is that the bees did not show up in 2021 or 2022 so detecting the bee can be challenging. It appears that the drought caused the bees to wait to emerge. The Mojave Poppy Bee is very specific in its choice of plants based on pollen samples from the bodies of the bees. Ninety percent of the pollen was from the Las Vegas Bear Poppy. The rest was mostly from indigo bush. We think it is likely to be the source for nectar for the bee since the Las Vegas Bear Poppy does not produce nectar. This new knowledge on the distribution and behaviors of the Mojave Poppy Bee will assist conservation efforts.

Technical Abstract: Growing concern about declines of many native pollinators has led to increased efforts to protect native bees. However, limited natural history and distributional data are available to inform these efforts for most North American bee species. The Mojave Poppy Bee, Perdita meconis Griswold, is a small fairy bee endemic to the eastern Mojave Desert only known to visit poppies in the genera Arctomecon and Argemone. Because of reported declines in populations of P. meconis, it has been targeted for protection under the endangered species act. Here we present the results of a three-year study (2020-2022) investigating the distribution and floral preferences of P. meconis in Clark County Nevada. We documented the current presence of P. meconis at multiple sites in Clark County, most of them historic. We found that populations of P. meconis and its primary host plant, Arctomecon californica, fluctuated dramatically from 2020-2022. The eastern Mojave experienced extreme drought conditions during these years, which apparently affected the populations of this rare bee and its floral resources. We conducted pollen analyses from pollen extracted from P. meconis specimens to determine its floral affinity (which plants it collects pollen from). We found that over 90% of the pollen extracted from the bodies of the bees and nearly 100% of the pollen carried on the bee’s scopa was from Arctomecon californica, confirming this bee as a floral specialist. Our data also show that P. meconis likely visits Psorothamnus, perhaps as a nectar source. These data can aid in Mojave Poppy Bee conservation efforts as they provide important distributional and dietary information that will assist conservation planners in their efforts.