Andrena ramaleyi

Justification:
Andrena ramaleyi is a solitary bee known from approximately 150 observations, and occurs in the Mountain West region of the United States, and can be found in shrublands and forests. Using all verified records of the species, the extent of occurrence is 330,580 km2. Although the species is widespread, and has been collected in abundance at one locality, it has not been observed since 2003. However, there has not likely been sufficient recent search effort to detect the species. Across the range of the species, impacts from drought and climate change, urbanization, and exposure to pesticides have been observed. These threats may be impacting the species at local levels. More research is needed to determine persistence of this species throughout its range, population trends, and basic habitat and ecology information. As such, it is assessed as Data Deficient.

There is little information about the habitat and ecology of Andrena ramaleyi. It is presumed to be a dietary specialist based on limited foraging records, visiting plants from the family Asteraceae for pollen. The species has been recorded in shrubland and evergreen forest of the Mountain West region of the United States. This species likely nests underground like all other Andrena (Danforth et al. 2019), but nests from this species have not been described. Nest cells from other members of this genus are located at the ends of the lateral burrows, which are typically lined with a waxy Dufour’s gland secretion (J. H. Cane 1981) that serves to both isolate the provision from pathogens in the surrounding soil and to regulate water uptake from the soil atmosphere (James H. Cane and Love 2021). Females provision each cell with a ball of pollen moistened with nectar on which they lay a single egg (Michener 2007). Records of this species come from June through September, with most records from August and September (Chesshire et al. 2023). Adults are assumed to emerge annually (Danforth et al. 2019).

Certain aspects of this species' biology may make it more vulnerable to some threats. Andrena ramaleyi is a ground nesting species, and nests may be harmed by certain agricultural practices such as tilling, which can kill bees nesting close to the surface (Williams et al. 2010). This species is presumed to be a dietary specialist, which has been linked to higher risk of extinction due to reduced host plant availability, especially under climate change scenarios (Roberts et al. 2011) and reduced effective population sizes (Packer et al. 2005). Additionally, Andrena have been reported to have low reproductive output because of the short adult life span, and a low rate of brood cell provisioning (reviewed in (Danforth et al. 2019). Other threats to bees generally include habitat loss or modification, climate change, pesticide use, exposure to pathogens from managed bee species, and competition with honey bees (Brown and Paxton 2009; Potts et al. 2010; Wojcik et al. 2018; Grab et al. 2019; Raven and Wagner 2021).

Conservation needs No known conservation actions are in place for this species. Observations of this species are known from Bureau of Land Management (BLM) and National Forest Service land, but this does not confer any specific protections to the species. Further research is needed to determine the overall size of the population and to identify trends and better understand existing threats. Specific conservation needs for this species have not been identified. Due to the importance of supporting wild bee populations for pollination services, general conservation practices are recommended including, restoring, creating, and preserving natural high-quality habitats to include suitable forage and nesting sites; limiting pesticide use on or near suitable habitat, particularly during the adult bee’s flight period; promoting farming and urban practices that increase pollinator-friendly plants in margin space; minimizing exposure of wild bees to diseases transferred from managed bees; and lastly, avoiding honey bee introduction to high-quality native bee habitat.

Surveys targeting this species are needed throughout its range to determine its persistence throughout its historic range. More information is needed about the population status, range limits, habitat, and ecology of this species.

(a. any taxonomic concerns about the validity of the species? b. any taxonomic revisions underway that would require a species reassessment.