Data for: Climate change is poised to alter mountain stream ecosystem processes via organismal phenological shifts

Climate change is affecting the phenology of organisms and ecosystem
processes across a wide range of environments. However, the mechanisms
linking organismal to ecosystem process change in complex communities are
uncertain. Here we examined how earlier snowmelt will alter the phenology
of stream organisms and ecosystem processes, via a large-scale field
experiment in outdoor stream channels. Extended low flows increased water
temperature, reducing production-to-respiration ratios by 32%. The stream
invertebrate community shifted due to phenological shifts in two-thirds of
the taxa, and emergent flux pulses of the dominant insect group
(Chironomidae) almost doubled, benefitting a generalist riparian predator.
Our study shows that climate change in mountain streams is poised to alter
the dynamics of stream food webs via fine-scale changes in
phenology—leading to novel predator-prey ‘matches’ or 'mismatches’
even when community structure and ecosystem processes appear stable at the
annual scale.