@article{457e2c40c0834da8a8b839c07f8331aa,
title = "Net-spinning caddisfly distribution in large regulated rivers",
abstract = "Most of the world's large rivers are dammed for the purposes of water storage, flood control, and power production. Damming rivers fundamentally alters water temperature and flows in tailwater ecosystems, which in turn affects the presence and abundance of downstream biota. We collaborated with more than 200 citizen scientists to collect 2,194 light trap samples across 2 years and more than 2,000 river km. Samples contained 16,222 net-spinning caddisfly (Hydropsyche) individuals across six species. We used these data to model the distribution of Hydropsyche throughout the Colorado River Basin in the western U.S.A. to identify the roles of water temperature, flows, and species-specific morphology in determining aquatic species distributions throughout a large arid watershed that has been heavily altered by damming. We predicted that water temperatures would determine Hydropsyche presence and abundance to a greater extent than diel variation in river stage associated with hydropower production. Among many species, adult female Hydropsychids are morphologically adapted to swim to deep-water oviposition sites. We predicted that the presence of this ability would negate the otherwise deleterious effects of high stage change on caddisfly egg mortality. We found that distributions of the two most widespread species, Hydropsyche occidentalis and Hydropsyche oslari (92% of total Hydropsyche captured), were both predicted by water temperatures. However, we also found that the abundance of H. oslari decreased by as much as 10-fold as diel stage change increased, despite the presence of female morphological adaptations for deep-water oviposition. We found sexual dimorphism and evidence for deep-water swimming adaptations in 5/6 species. Our results show that net-spinning caddisflies have species-specific responses to environmental variation and suggest that environmental flows designed to reduce diel stage change and destabilise water temperatures may improve habitat quality for these ubiquitous and important aquatic insects.",
keywords = "aquatic insects, citizen science, designer flows, morphology, temperature",
author = "Metcalfe, {Anya N.} and Muehlbauer, {Jeffrey D.} and Kennedy, {Theodore A.} and Yackulic, {Charles B.} and Dibble, {Kimberly L.} and Marks, {Jane C.}",
note = "Funding Information: Many hands make light (traps) work. We thank the hundreds of river runners, educators, fly fishers, government employees, and business owners who made time on the river to collect samples and make the large scale of this study possible. We thank B. Hendrix, A. Ingram, M. Daubert, E. Kortenhoeven, G. Garcia‐Pena, M. Ford, and M. Ryan for lab processing. We thank M. Ford for the photographs in Figure 4 . We are grateful to D. Ruiter for his support with specimen identification and verification. We thank T. Naumann, L. Evans, C. Fritzinger, B. Milligan, E. Wharton, D. Haymond, A. Holland, S. Evers, E. Farris, D. Perkins, P. Williams, P. Fleming, J. Lanci, R. Reid, M. Schroer, and D. Topping for logistical support. Funding was provided by the Western Area Power Administration and the U.S. Bureau of Reclamation (agreement #R15PG00030), Dinosaur National Monument (agreement #P15PG00258), a Science Support Partnership between the Upper Colorado Endangered Fish Recovery Program and the USGS (project ID #18‐R6‐01). Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Funding Information: Many hands make light (traps) work. We thank the hundreds of river runners, educators, fly fishers, government employees, and business owners who made time on the river to collect samples and make the large scale of this study possible. We thank B. Hendrix, A. Ingram, M. Daubert, E. Kortenhoeven, G. Garcia-Pena, M. Ford, and M. Ryan for lab processing. We thank M. Ford for the photographs in Figure?4. We are grateful to D. Ruiter for his support with specimen identification and verification. We thank T. Naumann, L. Evans, C. Fritzinger, B. Milligan, E. Wharton, D. Haymond, A. Holland, S. Evers, E. Farris, D. Perkins, P. Williams, P. Fleming, J. Lanci, R. Reid, M. Schroer, and D. Topping for logistical support. Funding was provided by the Western Area Power Administration and the U.S. Bureau of Reclamation (agreement #R15PG00030), Dinosaur National Monument (agreement #P15PG00258), a Science Support Partnership between the Upper Colorado Endangered Fish Recovery Program and the USGS (project ID #18-R6-01). Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Publisher Copyright: {\textcopyright} 2020 John Wiley & Sons Ltd.",
year = "2021",
month = jan,
doi = "10.1111/fwb.13617",
language = "English (US)",
volume = "66",
pages = "89--101",
journal = "Freshwater Biology",
issn = "0046-5070",
publisher = "Wiley-Blackwell",
number = "1",
}