Habitat restoration is a promising strategy to counteract wild bee declines, and consists of repairing degraded habitats and reestablishing native plant communities. To understand the effects of restoration on bees, we investigated bees and plants at three coastal restoration sites in California. We hypothesized that bee communities would vary depending on plant communities, and native plants would be important drivers of bee community composition. We collected 2,017 bees across 37 species and found 320 plant species. Bee communities were similar across all sites despite significant differences in plant communities, which may be explained by high floral diversity at all sites. Flowering native plants, and one non-native plant, were identified as significant drivers of bee community structure, highlighting the importance of prioritizing native plants in restoration projects to support diverse and resilient wild bee populations.

Phenotypic divergence is an important consequence of restricted gene flow in insular populations. This divergence can be challenging to detect when it occurs through subtle shifts in morphological traits, particularly in traits with complex geometries, like insect wing venation. Here, we employed geometric morphometrics to assess the extent of variation in wing venation patterns across reproductively isolated populations of the social sweat bee, Halictus tripartitus. We examined wing morphology of specimens sampled from a reproductively isolated population of H. tripartitus on Santa Cruz Island (Channel Islands, Southern California). Our analysis revealed significant differentiation in wing venation in this island population relative to conspecific mainland populations. We additionally found that this population-level variation was less pronounced than the species-level variation in wing venation among three sympatric congeners native to the region, Halictus tripartitus, Halictus ligatus, and Halictus farinosus. Together, these results provide evidence for subtle phenotypic divergence in an island bee population. More broadly, these results emphasize the utility and potential of wing morphometrics for large-scale assessment of insect population structure.