Floral resources shape parasite and pathogen dynamics in bees facing urbanization.

Area of Science:

• Urban ecology
• Pollinator health
• Disease ecology

Background:

• Urbanization alters wildlife resources, concentrating animal activity in green spaces like parks and gardens.
• The impact of these resource shifts on parasite and pathogen transmission dynamics in urban wildlife, particularly pollinators, remains understudied.
• Urban gardens are resource-rich islands within urban landscapes, potentially influencing disease transmission.

Purpose of the Study:

• To investigate how floral resource availability at local and landscape scales affects the prevalence of viruses and parasites in honey bees and bumble bees in urban gardens.
• To explore the relationship between floral resources, bee diversity, and parasite/pathogen transmission.
• To assess potential management strategies for mitigating disease transmission in urban pollinator populations.

Main Methods:

• Focused on urban gardens as study sites to examine floral resources and pollinator health.
• Assessed the prevalence of six RNA viruses and three parasites in honey bees and bumble bees.
• Analyzed the influence of garden size and flowering perennial plant abundance on parasite and pathogen richness, considering local and landscape scales.

Main Results:

• Garden size and flowering perennial abundance positively correlated with parasite and pathogen richness in bumble bees, indicating amplified transmission with increased resources.
• Parasitism rates in honey bees were positively associated with those in bumble bees, suggesting interspecies pathogen spillover.
• Larger garden size positively influenced bee diversity, which in turn negatively correlated with parasite and pathogen richness in bumble bees, suggesting a potential dilution effect.

Conclusions:

• Floral resource provisioning in urban gardens can amplify parasite and pathogen transmission in bumble bees.
• Bee diversity, enhanced by larger garden sizes, may offer a mechanism to mitigate disease spread.
• Further research is crucial to understand the trade-offs between resource provisioning and disease transmission for effective conservation in urban landscapes.