Brilliant Expansion Project: Summary of Aquatic Inventory Data of the Kootenay System near Brilliant Dam

Author: R.L. , L.Environmental Services Ltd

This document presents the results of the 1997 investigations and summarizes the findings of previous studies in the area. Included in this report are results and discussion for: - seasonal fish species composition, relative abundance, life history, and fish use patterns in lower Brilliant headpond and in the Kootenay River below Brilliant Dam; - habitat availability, suitability, and usage by fish in Brilliant headpond and in the Kootenay River below Brilliant Dam; - discharge rates, water temperatures, and total dissolved gases in the Kootenay River below Brilliant Dam, and water quality in Brilliant headpond; and - comparisons between results of the 1997 study and previous studies and, where differences were identified, a discussion of possible reasons for these differences.

In total, 23 fish species, representing seven families, have been recorded in the Brilliant study area since 1990. During the 1997 investigations, 19 species were recorded; 13 species in Brilliant headpond and 18 species in the lower Kootenay River. Burbot, carp, Umatilla dace, and shorthead sculpin were reported in previous studies, but were not recorded in 1997. Leopard dace and slimy sculpin were the only species recorded in the present study that had not been previously captured from the study area. However, both of these species have previously been reported to occur in the Canadian portion of the Columbia River basin.

The fish species assemblage in the study area includes two red-listed (i.e., white sturgeon and Umatilla dace) and three blue-listed (i.e., mottled sculpin, shorthead sculpin, and bull trout) species. White sturgeon has been assigned a “critically imperiled” status in the lower Columbia River system. Umatilla dace has been designated “imperiled” and shorthead sculpin is considered “imperiled or vulnerable”. Bull trout and mottled sculpin have both been assigned a “vulnerable” status. Umatilla dace and bull trout are the only listed species confirmed to occur in Brilliant headpond. Umatilla dace has been previously reported from the Brilliant headpond, but has not been captured in this area during any of the studies conducted since 1990.

In 1997, mountain whitefish were the most abundant species recorded in the Kootenay River below Brilliant Dam and contributed 38.4% to the total catch. Sucker species, as a group, were the next most abundant and contributed 30.6% to the total catch. Largescale sucker, bridgelip sucker, and longnose sucker were the three sucker species recorded and contributed 68.3, 18.3, and 13.4% to the identified sucker catch, respectively. Rainbow trout contributed 11.6% to the total catch, followed by (in decreasing order of abundance in the catch) sculpin spp. (4.5%), northern pikeminnow (4.1%), walleye (3.3%), redside shiner (2.5%), dace spp. (1.9%), and peamouth (1.5%). Other species captured represented minor components (i.e., less than 1.0%) of the fish species assemblage in the Kootenay River. Seven sportfish species were recorded in the lower Kootenay River in 1997. Mountain whitefish was the most abundant species in the sportfish catch, followed by rainbow trout, walleye, and white sturgeon. Kokanee, lake whitefish, and bull trout represented minor components of the total sportfish catch. Suckers were the dominant species in the non-sportfish catch, followed by sculpin spp., northern pikeminnow, redside shiner, longnose dace, and peamouth.

For full results summary, see report.

In total, 23 fish species, representing seven families, have been recorded in the Brilliant study area since 1990. During the 1997 investigations, 19 species were recorded; 13 species in Brilliant headpond and 18 species in the lower Kootenay River. Burbot, carp, Umatilla dace, and shorthead sculpin were reported in previous studies, but were not recorded in 1997. Leopard dace and slimy sculpin were the only species recorded in the present study that had not been previously captured from the study area. However, both of these species have previously been reported to occur in the Canadian portion of the Columbia River basin.

The fish species assemblage in the study area includes two red-listed (i.e., white sturgeon and Umatilla dace) and three blue-listed (i.e., mottled sculpin, shorthead sculpin, and bull trout) species. White sturgeon has been assigned a “critically imperiled” status in the lower Columbia River system. Umatilla dace has been designated “imperiled” and shorthead sculpin is considered “imperiled or vulnerable”. Bull trout and mottled sculpin have both been assigned a “vulnerable” status. Umatilla dace and bull trout are the only listed species confirmed to occur in Brilliant headpond. Umatilla dace has been previously reported from the Brilliant headpond, but has not been captured in this area during any of the studies conducted since 1990.

In 1997, mountain whitefish were the most abundant species recorded in the Kootenay River below Brilliant Dam and contributed 38.4% to the total catch. Sucker species, as a group, were the next most abundant and contributed 30.6% to the total catch. Largescale sucker, bridgelip sucker, and longnose sucker were the three sucker species recorded and contributed 68.3, 18.3, and 13.4% to the identified sucker catch, respectively. Rainbow trout contributed 11.6% to the total catch, followed by (in decreasing order of abundance in the catch) sculpin spp. (4.5%), northern pikeminnow (4.1%), walleye (3.3%), redside shiner (2.5%), dace spp. (1.9%), and peamouth (1.5%). Other species captured represented minor components (i.e., less than 1.0%) of the fish species assemblage in the Kootenay River. Seven sportfish species were recorded in the lower Kootenay River in 1997. Mountain whitefish was the most abundant species in the sportfish catch, followed by rainbow trout, walleye, and white sturgeon. Kokanee, lake whitefish, and bull trout represented minor components of the total sportfish catch. Suckers were the dominant species in the non-sportfish catch, followed by sculpin spp., northern pikeminnow, redside shiner, longnose dace, and peamouth.

For full results summary, see report.