About This Project

Specialist bees collect pollen from a narrow set of plants. Southern California’s deserts once hosted diverse woody legume specialist bees and their host plants. Are these specialist bees still present in their historic ranges? We hypothesize that specialist bee distributions have shifted in response to global change. This project will resurvey sites, collect bee and plant specimens and record interactions to compare current patterns to historic and modeled distributions.

Ask the Scientists

What is the context of this research?

Specialist bees are likely vulnerable to global change due to shifts in both their own climatic niche as well as their host plants' niches. Global change is likely to cause shifts in both distribution and life-history for taxa broadly, with evidence already present for life-history shifts in specialist bees. These factors could ultimately lead to a plant-pollinator mismatch, which could have adverse downstream effects on specialist bees by reducing their foraging efficiency and their niche partitioning of plant visitations. Modeling occurrence records of specialist bees and their host plant helps predict where overlaps may occur, but longer-term shifts are difficult to detect given collection gaps. This project's resurveys will address filling in these recent gaps, testing whether specialist bees have shifted their distribution in response to global change.

What is the significance of this project?

This project aims to fill gaps in our understanding of the current distributions for these specialist bees and their host plants. Resampling historic populations using museum records and ground truthing modeled distributional/phenological overlaps will provide valuable insights into understanding how global change could be impacting these species. The specimens collected for this project will also emphasize ecological associations, with direct species interactions and local plant community composition recorded. These specimens and their associated interaction metadata will also be digitized into the open access specimen data portals, including the Integrated Digitized Biocollections (iDigBio) and the Global Biodiversity Information Facility (GBIF), allowing their integration into other datasets and questions. In addition to our research goals, I will be taking both leaf litter and soil samples according to ATBI protocols for the targeted resampling sites.

What are the goals of the project?

Using species distribution models, we identified 62 specialist bee species overlapping 39 woody legume host plants in Southern California deserts. Of these, 24 bees and 7 legumes lack records in California for over a decade. We will resurvey sites based on historic and modeled ranges during a 2-week trip coinciding with peak legume flowering, guided by phenology models. Bee and plant specimens will be collected using prior resurvey protocols, with standardized search effort. All specimens will include both bee-plant interaction and community composition metadata. Bees will be identified and deposited at CCBER (UC Santa Barbara). Unique plant specimens per resurveyed site will be collected with duplicates and deposited at CCBER as well. Additional non-unique plant specimens with specialist bee interactions will be recorded using the tool FieldPrism. All specimens will be digitized to iDigBio and GBIF and used to analyze distributional shifts in my dissertation.