Inferring rare bumble bee species occurrences from nontarget bumble bee assemblages

Global declines in pollinator populations, particularly among insects, threaten the vital ecosystem services that such groups provide, which are crucial to the productivity of agricultural systems and the success of wild plant communities. Bumble bees are some of the most effective pollinators in temperate climates thanks to their cold hardiness, ability to buzz pollinate, and generalist foraging tendencies, but many species are experiencing sharp declines. The endangered rusty patched bumble bee (Bombus affinis) is one such species, now occupying only 8% of its historical range. As recovery efforts for B. affinis are hindered by imperfect detection and complex habitat requirements, I explored nontarget bumble bees as potential surrogates for inferring or predicting the local presence of B. affinis, focusing on taxonomic diversity (richness, abundance, composition), co-occurrence patterns, multispecies indicators, and B. affinis detection probability. Nontarget species richness, total abundance, and select species abundances were all significantly greater in detection sites, and several species co-occurred with B. affinis at greater than expected frequency. Three species – B. auricomus, B. fervidus, B. rufocinctus – emerged as surrogates across multiple lines of analysis, suggesting similar habitat requirements to B. affinis. These species may be used to guide recovery actions for B. affinis, helping to guide monitoring efforts by highlighting where to conduct surveys to increase knowledge of B. affinis grid occupancy. The results also emphasize what the best times are to conduct surveys to maximize detection of B. affinis.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Entomology

Grantor

University of Illinois Urbana-Champaign

Year dc:date

2025

Author dc:creator

• Garrett, Aidan P.

Contributors dc:contributor

• Bried, Jason T
• Zaya, David
• Harmon-Threatt, Alexandra

• Bombus affinis
• bumble bee
• surrogate species
• conservation

Statement dc:rights

• Copyright 2025 Aidan Garrett

Language dc:language

en

Handle dc:identifier

https://hdl.handle.net/2142/132691

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/132691