The Tribe’s vision is to restore harvestable populations of Bull Trout and Westslope Cutthroat Trout for Tribal members in the mainstem Pend Oreille and Priest rivers and associated tributaries. From a habitat restoration perspective, there is a need to remedy legacy and current impacts on watershed processes and native resident fish populations in these areas, especially with respect to adfluvial Bull Trout and Westslope Cutthroat Trout– a life history that is of particular subsistence interest to Kalispel Tribe members.  Habitat forming processes (runoff, sediment, and wood), when functioning and intact, help support adequate food (both quantity and quality) to support native trout. Like their salmon relatives, the odds of Bull Trout and Westslope Cutthroat Trout becoming adults are small. However, the likelihood is even less now due to habitat degradation. Climate change is a factor as well. Hotter, drier summers and lower snowpacks lead to less water in the rivers (Kittitas Conservation Trust 2018). In a healthy food web, Bull Trout and Westslope Cutthroat Trout play important roles as both predator and prey. But, human-caused impacts and climate change are creating an imbalance. Non-native fish species, including Eastern Brook Trout, Smallmouth Bass, and Northern Pike, prey upon native trout, making suppression and eradication in the Kalispel Non-Native Fish Suppression Project and other FERC licensee-funded eradication efforts extremely important. While we cannot directly address climate change, we can rehabilitate human-impacted streams and make them more resilient and manage non-native fish. The proposed project seeks to continue to improve the aquatic habitat at Big Meadows, increase climate change resiliency and habitat function within Mill and Indian creeks, and increase cold water refuge areas at two tributary junctions in the Pend Oreille River identified in Mejia et al. (2020). Watersheds and actions were prioritized based on the approach described in our Independent Science Review Panel (ISRP) proposal.

To create more climate-resilient watersheds, it is important to manage for temporal environmental variability, spatial heterogeneity, and hydrologic connectivity (Grantham et al. 2019). With respect to the temporal variability of freshwater systems, there is a recognition that restoration strategies that go beyond the natural flow regime (Poff 2018) are necessary and include future predictions for sediment supply and wood recruitment (the other major habitat-forming processes in the inland northwest).  

Managing for spatial heterogeneity involves managing landscapes for physical processes that support diverse life histories and buffer desired species and services from change (Grantham et al. 2019). Spatial variation in ecosystems is recognized to be hierarchical, in which various processes interact to create and modify patterns of environmental heterogeneity at multiple scales (Wu and Loucks 1995)  For example, seasonal high flows transport and deposit sediment to other parts of the river channel and floodplain, influencing reach scale (100–1000 m) habitat patterns. Sediment and wood can also interact with large wood and debris generated from hillslopes to form scour pools and log jams that, in turn, influence local (1–10 m) habitat complexity. This dynamically changing distribution of reach and local scale habitat areas supports a diversity of species and bolsters ecological resilience.

Hydrologic connectivity refers to the transfers of matter, energy, and organisms between various components of the hydrological cycle and adjacent terrestrial ecosystems. It has a fundamental control on freshwater ecosystem functions and integrity (Pringle 2003). Ward (1989) identified four relevant dimensions of hydrologic connectivity: longitudinal (upstream–downstream linkages between habitats), lateral (connectivity between a river channel or lake and adjacent floodplains and riparian areas), vertical (connectivity with the hyporheic zone, groundwater, and the atmosphere), and temporal (seasonal interactions among the three spatial dimensions). Connectivity of heterogeneous habitat types contributes to resilience by sustaining a diverse pool of species that use a variety of habitats to satisfy life history requirements (Timpane-Padgham et al. 2017).  Hydrologic connectivity also contributes to resilience by allowing biota to recolonize disturbed areas or replenish depleted populations. This is essential for facilitating range shifts of organisms to areas of remaining suitable habitat in the context of climate change.

References:

Grantham, T.E., J.H. Matthews, and B.P. Bledsoe. 2019. Shifting currents: Managing freshwater systems for ecological resilience in a changing climate. Water Security (8)

Kittitas Conservation Trust. 2018. Bull trout in the food web.  Available at https://www.kittitasconservationtrust.org/2018/09/04/bull-trout-food-web/.  Accessed December 23, 2019.

Mejia, F.H.; C.E Torgersen; E.K. Berntsen, J.R. Maroney, J.M. Connor, A.H. Fullerton, J.L. Ebersole, and M.S. Lorang. 2020. Longitudinal, lateral, vertical, and temporal thermal heterogeneity in a large impounded river: Implications for cold-water refuges. Remote Sens.:12, 1386.  https://doi.org/10.3390/rs12091386

Poff, N. L. 2018. Beyond the natural flow regime? Broadening the hydro-ecological foundation to meet environmental flows challenges in a non-stationary world, Freshwater Biol. 63 (8) 1011–1021.

Pringle, C. 2003. What is hydrologic connectivity and why is it ecologically important? Hydrol. Process. (17) 2685–2689.

Timpane-Padgham, B.L., T. Beechie, and T. Klinger. 2017. A systematic review of ecological attributes that confer resilience to climate change in environmental restoration, PLoS One 12 (3) e0173812.

Ward, J.V. 1989. The four-dimensional nature of lotic ecosystems, J. North Am. Benthol. Soc. 8 (1) 2–8.

Wu, J. and O.L. Loucks. 1995. From balance of nature to hierarchical patch dynamics: a paradigm shift in ecology, Quart. Rev. Biol. 70 (4):439–466.