Functional traits linked to pathogen prevalence in wild bee communities

Area of Science:

• Ecology
• Pathogen Dynamics
• Pollinator Health

Background:

• Pollinator declines are a significant environmental concern, necessitating research into disease impacts.
• Pathogen prevalence in bee communities is influenced by various factors, yet species-specific drivers remain understudied.
• Functional traits are increasingly used to predict species' responses to environmental stressors.

Purpose of the Study:

• To investigate the relationship between wild bee functional traits and the prevalence of trypanosomes, neogregarines, and Nosema ceranae.
• To compare the predictive power of trait-based versus taxonomy-based models for pathogen prevalence.
• To examine intra-specific size variation in relation to pathogen prevalence in Bombus impatiens.

Main Methods:

• Assessed functional traits (body size, phenology, nesting, sociality, foraging) across wild bee species.
• Quantified prevalence of trypanosomes, neogregarines, and Nosema ceranae.
• Developed and compared trait-based and taxonomy-based models for pathogen prevalence.
• Analyzed intra-specific size variation in Bombus impatiens for pathogen associations.

Main Results:

• A trait-based model best explained neogregarine prevalence, while a taxonomy-based model fit Nosema ceranae prevalence.
• Augochlorella aurata showed higher trypanosome prevalence; larger bees and those active later in the season had lower trypanosome prevalence.
• No significant intra-specific size-pathogen prevalence patterns were found in Bombus impatiens.

Conclusions:

• Functional traits can predict pathogen prevalence, but their importance varies by pathogen and is not always superior to taxonomic relationships.
• Understanding the interplay between bee traits, taxonomy, and pathogens is crucial for effective pollinator conservation strategies.
• Species-specific ecological factors and pathogen dynamics shape disease susceptibility in wild bee communities.