Native Fish Need a Natural Flow Regime, Not More Water Development (No Duh)
Phaedra Budy3,1,2, Casey A. Pennock*1,2, William W. Macfarlane1,2, Matthew J. Breen3, Justin Jimenez4, and John C. Schmidt1,5
1Department of Watershed Sciences and The Ecology Center, Utah State University, Logan, UT 84322, phaedra.budy@usu.edu, Casey.Pennock@usu.edu, wally.macfarlane@usu.edu
2U.S. Geological Survey, Utah Cooperative Fish and Wildlife Research Unit, Utah State University, Logan UT, 84322
3Utah Division of Wildlife Resources, Northeastern Regional Office, Vernal, UT 84078, mattbreen@utah.gov
4U. S. Bureau of Land Management, Utah State Office, Salt Lake City, UT 84101, jjimenez@blm.gov
5Center for Colorado River Studies, Utah State University, Logan, UT, 84322, jack.schmidt@usu.edu
Water development has threatened the ecological integrity of riverine ecosystems. Increasing demand for water, persistent drought, and climate change exacerbate the effects of habitat degradation and loss in altered systems such as the Colorado River basin, USA. Today, biologists in the basin are challenged to identify management actions that benefit native fishes while not hindering water development or management. Herein, we discuss the importance of the natural flow regime for functioning riverine ecosystems and provide examples from four tributaries to the middle Green River, a major headwater branch of the Colorado River. These rivers represent a gradient of impacts ranging from water abstraction to the point of complete seasonal desiccation to a relatively natural flow regime, and consequently have maintained different levels of in-stream habitat complexity and native fish persistence. Despite decades of intense management, endangered species continue to lack self-sustaining populations and other imperiled native species have been extirpated from over half their ranges, which begs the question of whether water development and fish conservation can be balanced?