Cooperative Fish and Wildlife Research Units Program:
Education, Research and Technical Assistance for Managing Our Natural Resources

Project

Native Fish Conservation Assessment in Desert Rivers of the IMW.

April 2020 - January 2022

Personnel

Participating Agencies

The San Rafael River meanders around low-tech post-assisted log structures (PALs) installed as part of a restoration project aimed at increasing in-stream habitat and hydrologic complexity to benefit imperiled native fishes.

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Research Publications

Research Publications	Publication Date
Pennock, C., P. Budy, W.W. Macfarlane, M.J. Breen, J. Jimenez, and J.C. Schmidt. In press. Native fish need a natural flow regime. AAccepted 16 Nov, 2021 Fisheries as a ‘Perspectives’ Article. USGS FSP IP-130996.	November 2021
Pennock, C.A, L. Bruckerhoff, K.B. Gido, A.L. Barkalow, M.J. Breen, P. Budy, W.W. Macfarlane, and D.L. Propst. 2022. Failure to achieve recommended environmental flows coincides with declining fish populations: Long-term trends in regulated and unregulated rivers. Freshwater Biology https://doi.org/10.1111/fwb.13966. USGS FSP IP- 134441 (LB). \| Abstract	July 2022	Dams can be operated to mimic components of the natural flow regime to minimize impacts on downstream ecosystems. However, infrastructure, societal needs, and watershed runoff constrain which and when flow regime attributes can be mimicked. We compared fish assemblage responses, including native and nonnative species, over two decades of managed environmental flows to those in a river retaining a relatively natural flow regime. Both of these arid-land rivers are within the Colorado River basin and have experienced declines in watershed runoff over the past twenty years. We predicted fish-flow relationships would be conserved across time and between managed and unmanaged rivers. Declines in flow in both rivers coincided with declines in some native fishes, and more native and nonnative fish species exhibited declines in the managed river than in the unmanaged river. Our ability to detect previously documented native fish-flow relationships diminished in the managed river system because established environmental flow targets were not met due to water management, but we detected these fish-flow relationships in the unmanaged river. Our results suggest declining watershed runoff and increased consumptive water use could reduce the effectiveness of environmental flows that have lower priority in most years.
Pennock, C.A., Budy P, Macfarlane, WW. 2022. Effective conservation and restoration of desert riverscapes requires conservation and restoration of in-stream flows with rehabilitation approaches tailored to water availability. Invited: Frontiers in Environmental Science 10:870488. doi: 10.3389/fenvs.2022.870488. USGS FSP IP- 138466. \| Abstract	May 2022	Desert riverscape restoration practitioners must contend with compounding effects of increasing human water demand, persistent drought, nonnative species establishment, and climate change, which further stress desert riverine ecosystems such as rivers in the Colorado River basin, USA. Herein, we provide our perspective on the importance of natural flows, large floods in particular, for successful conservation and restoration of riverscapes. We present ideas developed from our experience with restoration projects across multiple desert tributary rivers with varying levels of habitat degradation and water abstraction. We propose broad-scale measures such as protection of in-stream flows, tailoring restoration efforts to available annual water availability, and working with nature using low-tech process-based techniques to more completely address the mechanisms of habitat degradation, such as flow reduction and vegetation-induced channel narrowing. Traditionally, restoration efforts in the Colorado River basin take place at relatively fine-scales, at convenient locations and, largely focus on reducing nonnative plant and fish species. We suggest that we need to think more broadly and creatively, and that conservation or restoration of natural flow regimes is crucial to long-term success of almost all management efforts for both in-stream and riparian communities.

Technical Publications

Technical Publications	Publication Date
Pennock, C. A., W. W. Macfarlane, P. Budy, J. Jimenez, and J. Goodell. 2021. Conservation, restoration and monitoring plan for the lower White River, Utah. UTCFWRU 2022(1):1-78.	January 2022

Presentations

Presentations	Presentation Date
Budy, P., C.A. Pennock, W.W. Macfarlane, M.J. Breen, J. Jimenez, and J.C. Schmidt. 2022. Native Fish Need a Natural Flow Regime. Invited. Oral Presentation, RiversEdge West, 20^th Annual Conference, "Learn from the last 20 years and plan for the next". Hybrid: Grand Junction, CO.	February 2022
Pennock C, Macfarlane W, Budy P, Jimenez J, Goodell J. 2022. Effective conservation and restoration of desert riverscapes must include conservation of in-stream flows: What can we learn from a case study from the White River, Utah?	February 2022
Budy, P. 2014. Challenges to desert fish conservation and river restoration in the arid West: How can we avert the perfect storm? University of Missouri, Dept. of Fisheries and Wildlife Sciences. Invited Lecture: 5 March, 2014 Michael Dunmire Lecture Series.	March 2014
Pennock, C., Z. Ahrens, M. McKinstry, P.MacKinnon, P. Budy, and K. Gido. 2020. Emergence of barriers at river-reservoir inflows create a conservation conundrum for native fish management in the Colorado River Basin. National American Fisheries Society Conference, Columbus, Ohio. 30 August - 3 September 2020.	August 2020