Climate change and increased freshwater diversion from streams are likely to cause increased water temperatures and potentially shifts in dissolved oxygen in California's coastal riverine ecosystems. How insects at the base of the aquatic food web respond to those environmental changes may play a role in the transfer of energy from primary productivity through the food web to fish and birds, including endangered salmonid populations. We are examining thermal sensitivity of metabolic rate and aerobic scope in order to assess metabolic efficiency in food use among armored (caddisflies) and unarmored insect grazers (mayflies), as well as insect carnivores (stoneflies). We are also generating mRNA biomarkers for thermal performance using RNA-seq approaches in widespread species that will be used for assessing metabolic rate and efficiency variation across a wide range of watersheds in coastal California's freshwater ecosystems. Combined with population-level genetic variation, historical collection records, and climate envelope models, we hope to develop a predictive understanding for how global change will impact the flow of energy in riverine ecosystems.
Funded by the Moore Foundation as part of the Berkeley Initiative for Global Change Biology (BiGCB)