Andrena congrua

Justification:
Andrena congrua is a solitary bee species that occurs in California and southern Oregon, United States. Using all records, the extent of occurrence (EOO) is 126,602 km2. The species has not been observed anywhere in its range since 2012. The species has been recorded foraging from a range of plant families, although its dietary breadth is not well understood. It has been observed in shrublands, forests, and agricultural areas. Across the range of the species, impacts from climate change and drought, habitat loss and degradation, and pesticide exposure have been observed. These threats may be acting on the species at local levels. More information is needed to determine if this species is extant throughout its entire range, to better understand life history, and the degree to which threats are acting on the population. RANK STATEMENT

Food habits comment: Andrena congrua has been recorded foraging from plants from the families Papaveraceae, Fabaceae, Rosaceae, Ericaceae, with most floral records from the family Boraginaceae (LaBerge 1977). There is not enough information about this species to determine dietary breadth. Habitat comment: This species has been recorded in shrublands, forests, and agricultural areas, between 82 and 3513 m Reproduction comment: 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 (Cane 1981) that serves to both isolate the provision from pathogens in the surrounding soil and to regulate water uptake from the soil atmosphere (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). Phenology comment: Records of this species come from April through June (Chesshire et al. 2023). Adults are assumed to emerge annually (Danforth et al. 2019).

Threat comments: Specific threats to this species have not been identified. It may be impacted by climate change and drought, which has been severe across much of its range. Since 2000, the Southwest U.S. has seen the worst drought in 1200 years (Williams, Cook, and Smerdon 2022). Drought can reduce the abundance of flowering plants on a landscape scale, and also reduce pollen and nectar quality (Wilson Rankin, Barney, and Lozano 2020). Drought conditions have been shown to reduce the diversity and abundance of native bees (Minckley, Roulston, and Williams 2013; Hung et al. 2021). Certain aspects of this species' biology may make it more vulnerable to some threats. Andrena congrua 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). 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). Threats Threats: Timing: Scope: Severity: Impact Score: 1. Residential & commercial development -> 1.1. Housing & urban areas 1. Residential & commercial development -> 1.2. Commercial & industrial areas 2. Agriculture & aquaculture -> 2.1. Annual & perennial non-timber crops -> 2.1.3. Agro-industry farming 7. Natural system modifications -> 7.1. Fire & fire suppression -> 7.1.1.Increase in fire frequency/intensity 7. Natural system modifications -> 7.1. Fire & fire suppression -> 7.1.2. Suppression in fire frequency/intensity 8. Invasive and other problematic species, genes, and diseases -> 8.1 Invasive non-native/alien species/diseases -> 8.1.2. Named species 9. Pollution -> 9.3 Agricultural and forestry effluents -> 9.3.3 Herbicides and Pesticides 11. Climate change & severe weather -> 11.1. Habitat shifting & alteration 11. Climate change & severe weather -> 11.2.Droughts 11. Climate change & severe weather -> 11.3.Temperature extremes Conservation Actions Conservation needs No known conservation actions are in place for this species. Protected/Managed area comment: Observations of this species are known from National Park Service and U.S. Forest Service land, but this does not confer any specific protections to the species. Management comment: 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. Conservation Actions Needed 1. Land/water protection -> 1.2. Resource & habitat protection 2. Land/water management -> 2.3. Habitat & natural process restoration 4. Education & awareness -> 4.3. Awareness & communications 5. Law & policy -> 5.2. Policies and regulations Research needs Research need comment: More information is needed about the population status, population trend, existing threats, range limits, habitat, and ecology of this species. Surveys targeting this species are needed throughout its range to determine its persistence throughout its historic range. Research Needed 1. Research -> 1.2. Population size, distribution & trends 1.3. Life History and Ecology 1.5. Threats 1.6 Conservation actions 3. Monitoring -> 3.1. Population trends 3.4. Habitat trends Assessment Date of assessment (month-day-year): 3-19-2025 Assessors names (use * to indicate primary assessor, typically the participant with most experience/knowledge of the species): Saff Killingsworth Reviewer(s): Contributors(s): For a full list of the 162 institutions that contributed to the Chesshire et al. dataset, please see Chesshire et al. 2023, S1. Facilitator(s) and compiler(s): Paige R. Chesshire, Erica E. Fischer, Nicolas J. Dowdy, Terry L. Griswold, Alice C. Hughes, Michael C. Orr, John S. Ascher, Laura M. Guzman, Keng-Lou James Hung, Neil S. Cobb and Lindsie M. McCabe Red List Category and Criteria: Rank/Criteria Justification: Andrena congrua is a solitary bee species that occurs in California and southern Oregon, United States. Using all records, the extent of occurrence (EOO) is 126,602 km2. The species has not been observed anywhere in its range since 2012. The species has been recorded foraging from a range of plant families, although its dietary breadth is not well understood. It has been observed in shrublands, forests, and agricultural areas. Across the range of the species, impacts from climate change and drought, habitat loss and degradation, and pesticide exposure have been observed. These threats may be acting on the species at local levels. More information is needed to determine if this species is extant throughout its entire range, to better understand life history, and the degree to which threats are acting on the population. RANK STATEMENT Rank reasons This species is a solitary bee that occurs in Califorina and southern Oregon. Using all verified records of the species, the range extent is 126,602 km2. This species occurs in shrublands, forests, and agricultural areas. The species forages from a wide range of plant families. Across the range of the species, impacts from climate change, pesticide exposure, and urbanization have been observed. These threats may be acting on the species at local levels. Although the species is widespread and occurs in several habitat types, it has not been recently observed. It is unclear if the species is extant throughout its entire range. Rank Statement NatureServe Specific Text (NOT OTHERWISE INCLUDED IN ABOVE TEXT): For Rank Calculator: 1. Element occurrences (using separation distance of 5,000 m): 1 (A) 1. Estimated Number of Element Occurrences Comments: Using all records from the last 30 years (since 2015), this species is known from only one occurrence using a 5 km separation distance. 2. Population size: Unknown 3. Viability/Ecological integrity (choose one) 1. Number of occurrences with good viability/ecological integrity: Unknown 2. Percent of area occupied (For Species with Known AOO): N/A 4. Environmental Specificity: A. Broad. Generalist or community with all key requirements common. 1. Environmental specificity comments: This species has been recorded foraging from a wide range of plant families, although the dietary breadth is not well understood. 5. Intrinsic Vulnerability: B. Moderately vulnerable 1. Intrinsic vulnerability comments: 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). 6. Trend 1. Short Term Trend: Unknown 2. Comments: Abundance estimates and population trends are not known for this species. 3. Long Term Trend: Unknown 4. Comments: Abundance estimates and population trends are not known for this species. For Biotics Global Element Characterization: 1. Habitat Forest/Woodland, Shrubland/chaparral, Cropland/Hedgerow 2. Food Habits 1. Adult: nectarivore 2. Immature: nectarivore Literature References: Brown, Mark J. F., and Robert J. Paxton. 2009. “The Conservation of Bees: A Global Perspective.” Apidologie 40 (3): 410–16. Cane, James H., and Byron G. Love. 2021. “Hygroscopic Larval Provisions of Bees Absorb Soil Water Vapor and Release Liquefied Nutrients.” Apidologie 52 (6): 1002–16. Cane, J. H. 1981. “Dufour’s Gland Secretion in the Cell Linings of Bees (Hymenoptera: Apoidea).” Journal of Chemical Ecology 7 (2): 403–10. Chesshire, Paige R., Erica E. Fischer, Nicolas J. Dowdy, Terry L. Griswold, Alice C. Hughes, Michael C. Orr, John S. Ascher, et al. 2023. “Completeness Analysis for over 3000 United States Bee Species Identifies Persistent Data Gap.” Ecography, February. https://doi.org/10.1111/ecog.06584. Danforth, Bryan N., Robert L. Minckley, John L. Neff, and Frances Fawcett. 2019. The Solitary Bees: Biology, Evolution, Conservation. Princeton University Press. Grab, Heather, Michael G. Branstetter, Nolan Amon, Katherine R. Urban-Mead, Mia G. Park, Jason Gibbs, Eleanor J. Blitzer, Katja Poveda, Greg Loeb, and Bryan N. Danforth. 2019. “Agriculturally Dominated Landscapes Reduce Bee Phylogenetic Diversity and Pollination Services.” Science 363 (6424): 282–84. Hung, Keng-Lou James, Sara S. Sandoval, John S. Ascher, and David A. Holway. 2021. “Joint Impacts of Drought and Habitat Fragmentation on Native Bee Assemblages in a California Biodiversity Hotspot.” Insects 12 (2). https://doi.org/10.3390/insects12020135. LaBerge, Wallace E. 1977. “A Revision of the Bees of the Genus Andrena of the Western Hemisphere. Part VIII. Subgenera Thysandrena, Dasyandrena, Psammandrena, Rhacandrena, Euandrena, Oxyandrena.” Transactions of the American Entomological Society 103 (1): 1–143. Lehner, Abigail M. 2022. “Biodiversity and Foraging Preferences of Bee Communities At Pinnacles National Park Over Time.” Utah State University. https://search.proquest.com/openview/b4a5e5476452fb3a9b797538130594aa/1?pq-origsite=gscholar&cbl=18750&diss=y. Michener, Charles Duncan. 2007. The Bees of the World. Vol. 1. JHU Press. Minckley, Robert L., T’ai H. Roulston, and Neal M. Williams. 2013. “Resource Assurance Predicts Specialist and Generalist Bee Activity in Drought.” Proceedings. Biological Sciences / The Royal Society 280 (1759): 20122703. Potts, Simon G., Jacobus C. Biesmeijer, Claire Kremen, Peter Neumann, Oliver Schweiger, and William E. Kunin. 2010. “Global Pollinator Declines: Trends, Impacts and Drivers.” Trends in Ecology & Evolution 25 (6): 345–53. Raven, Peter H., and David L. Wagner. 2021. “Agricultural Intensification and Climate Change Are Rapidly Decreasing Insect Biodiversity.” Proceedings of the National Academy of Sciences of the United States of America 118 (2). https://doi.org/10.1073/pnas.2002548117. Rousseau, Josée S., S. Hollis Woodard, Sarina Jepsen, Brianne Du Clos, Alison Johnston, Bryan N. Danforth, and Amanda D. Rodewald. 2024. “Advancing Bee Conservation in the US: Gaps and Opportunities in Data Collection and Reporting.” Frontiers in Ecology and Evolution 12. https://doi.org/10.3389/fevo.2024.1346795. Williams, A. Park, B. I. Cook, and S. E. Smerdon. 2022. “Rapid Intensification of the Emerging Southwestern North American Megadrought in 2020–2021.” Nature Climate Change 12 (3): 232–34. Williams, N. M., Elizabeth E. Crone, T’ai H. Roulston, Robert L. Minckley, Laurence Packer, and Simon G. Potts. 2010. “Ecological and Life-History Traits Predict Bee Species Responses to Environmental Disturbances.” Biological Conservation 143 (10): 2280–91. Wilson Rankin, Erin E., Sarah K. Barney, and Giselle E. Lozano. 2020. “Reduced Water Negatively Impacts Social Bee Survival and Productivity Via Shifts in Floral Nutrition.” Journal of Insect Science 20 (5). https://doi.org/10.1093/jisesa/ieaa114. Wojcik, Victoria A., Lora A. Morandin, Laurie Davies Adams, and Kelly E. Rourke. 2018. “Floral Resource Competition Between Honey Bees and Wild Bees: Is There Clear Evidence and Can We Guide Management and Conservation?” Environmental Entomology 47 (4): 822–33.

Conservation needs No known conservation actions are in place for this species. Protected/Managed area comment: Observations of this species are known from National Park Service and U.S. Forest Service land, but this does not confer any specific protections to the species. Management comment: 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.

Research need comment: More information is needed about the population status, population trend, existing threats, range limits, habitat, and ecology of this species. Surveys targeting this species are needed throughout its range to determine its persistence throughout its historic range.

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