Species with more volatile population dynamics are differentially impacted by weather

Area of Science:

• Ecology
• Climate Science
• Zoology

Background:

• Population dynamics are often explained by climatic variation, but research typically focuses on single species.
• Understanding how weather influences diverse taxa is crucial for ecological insights.
• Previous studies lack comparative analyses across multiple species with varying population dynamics.

Purpose of the Study:

• To conduct a comparative analysis of butterfly population dynamics in response to climatic variation.
• To explore commonalities in weather responses among 50 co-occurring butterfly species.
• To investigate the differential impact of weather on species with stable versus volatile population dynamics.

Main Methods:

• Utilized a multi-decadal dataset of butterfly population dynamics from 10 Northern California sites.
• Employed a hierarchical Bayesian modeling framework for comparative analysis.
• Analyzed responses to weather variables, including precipitation and El Niño Southern Oscillation (ENSO) indices.

Main Results:

• Identified distinct weather impacts on volatile (irruptive) versus stable butterfly species.
• Precipitation-related variables and ENSO indices showed a more pronounced effect on highly volatile species.
• Demonstrated a common influence of weather patterns on taxa exhibiting similar population dynamics.

Conclusions:

• Weather conditions, particularly precipitation and ENSO, differentially affect butterfly species based on their population volatility.
• These climatic factors likely influence vegetation resources, indirectly impacting volatile butterfly populations.
• Findings suggest new research avenues in biotic-abiotic interactions and the commonality of ecological responses.