Changes in occurrence, richness, and biological traits of dragonflies and damselflies (Odonata) in California and Nevada over the past century

摘要: Increases in water demand, urbanization, and severity of drought threaten freshwater ecosystems the arid western United States. Historical assessments change assemblages over time can help determine effects these stressors but, to date, are rare. In present study, we resurveyed 45 sites originally sampled 1914–1915 for Odonata (dragonflies damselflies) adults throughout central California northwestern Nevada, USA. We examined changes species occurrence rates, taxonomic richness, biological trait composition relation climate human population increases. While richness at individual did not significantly, found that odonate have become more similar across sites. Homogenization is a result expansion highly mobile habitat generalists, decline both specialists with an overwintering diapause stage. Using multi-species mixed-effects model, overall occurrences increased higher minimum temperatures. Habitat stage, however, occurred less often warmer regions areas precipitation. populated Life history traits Odonata, such as dispersal ability, specialization, diapause, useful predictors species-specific responses urbanization this region.