GMSMON-17 WILLISTON RESERVOIR TRIBUTARY - BC Hydro

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May 22, 2012 Report No. 1114920016-R-Rev0-2000 20 GMSMON-17 WILLISTON RESERVOIR TRIBUTARY HABITAT REVIEW reached record levels for these creek systems this year. These high flows may have caused the extensive erosion noted at certain sections along Lamonti Creek. 3.5.2 Factor Ross and Ole Creeks Four transects were established at both Factor Ross and Ole creeks and consisted of transects FV1-FV4 and OV1-OV4, respectively. Vegetation surrounding the mouths of each creek included a mixture of large black cottonwood, hybrid white spruce, sub-alpine fir, paper birch, mountain alder, black twinberry, bunchberry, twinflower, wild sarsaparilla (Aralia nudicaulis), and extensive moss cover of red-stemmed feathermoss, step moss, knight’s plume, juniper haircap moss (Polytrichum juniperinum), and pelt lichens (Peltigera sp.). Blow-down was not quite as extensive at the northern end of Williston reservoir and large riparian trees (e.g., black cottonwood) were prevalent. All tree quadrants for both Factor Ross and Ole creeks had at least one tree. The highest number of trees was found in FV3 and OV3 which each had three trees. FV3 had two lodgepole pine and one paper birch; all Layer 1 trees, and OV3 had three paper birch (one - Layer 1, and two – Layer 2). Bank characteristics of Factor Ross Creek appeared more stable than Six Mile and Lamonti creeks as less bank scouring and erosion was noted along the banks of this creek. The bank near FV3 was very stable and was composed primarily of rock with the transect starting above a small cliff area. Similarly, along Ole Creek, the upper reaches of the creek flowed through a steeply incised rocky canyon and bank erosion appeared less prevalent at the lower reaches. Canopy cover over Factor Ross and Ole creeks was much higher than at Six Mile or Lamonti creeks with lowest cover found at OV2 (20% cover) and highest at FV1 (60% cover). Copies of all data cards for vegetation including photo point record forms, tree plots and vegetation transects are found in Appendix H. 4.0 DISCUSSION 4.1 Fish 4.1.1 Spawner Surveys Spawning fish, redds or eggs were not observed in any of the creeks during the spawner surveys. Suitable spawning substrates were observed in the creeks but stream conditions were generally not favourable for spawning during the surveys. A larger than normal snowpack and heavy precipitation in 2011 resulted in atypical stream conditions during the spring surveys, with much colder water temperatures and higher discharges than were expected. These anomalous conditions affected the suitability of the streams for spawning and our ability to effectively observe and quantify fish spawning activity. During the first site visit, temperatures varied between 0 and 3.5°C, which is below the preferred spawning temperature for Arctic Grayling (above 4°C), and much lower than the preferred temperature ranges of rainbow trout and suckers (10 to 12°C) (McPhail 2009). During the second site visit, water temperatures remained cold (3 to 5°C) and discharges were very high, nearing freshet conditions, which is not ideal for Rainbow Trout spawning. High flows and turbid water also impeded visual observations of spawners and redds, made snorkelling and angling ineffective, and made wading in the streams difficult.
May 22, 2012 Report No. 1114920016-R-Rev0-2000 21 GMSMON-17 WILLISTON RESERVOIR TRIBUTARY HABITAT REVIEW Because of the atypical stream conditions during our surveys, it is not possible to say how much spawning by target species occurred in the study creeks. It is possible that Rainbow Trout spawned in some of the creeks but much later than normal when flows receded and temperatures increased. Alternatively, the atypical conditions in the streams in 2011 could have resulted in very little successful spawning at all. Many fish species found in northern latitudes typically spawn only every few years when conditions are ideal (McPhail 2009). None of the study creeks currently have discharge gauges or temperature loggers. Monitoring water temperature and/or stream discharge would improve understanding of environmental cues and preferred conditions for spawning by the target species in Williston Reservoir tributaries. In addition, monitoring temperature or discharge would allow researchers to plan the timing of field visits to coordinate with preferred stream conditions of target species. Therefore, we recommend the addition of long-term temperature monitoring to the Williston tributary enhancement monitoring program. Options for temperature monitoring include thermistors with satellite up-link for remote real-time updates, or archival loggers that could be downloaded periodically during a site visit. 4.1.2 Juvenile and Small-Bodied Fish Survey One of the main objectives of the electrofishing survey was to estimate the abundance of juvenile fish of the target species. Estimates of the numbers of juvenile fish will be compared before and after enhancement to reflect the effectiveness of habitat enhancement on adfluvial spawner access to the tributaries and rearing habitat within these streams. However, catches of fish, especially of target species, were so low that abundance estimates could not be generated using the proposed analysis. All sites had catches of less than ten fish of all species combined. Rainbow Trout, one of the target species, were caught at only a few sites, with four or fewer fish per site. These small catches suggest that densities of fish, both target and non-target species, are quite low in the reaches of the tributaries sampled (at least during the 2011 survey). Electrofishing surveys conducted during this study do provide baseline data about the species and life stages present in the study creeks. Rainbow Trout (40 to 120 mm) were present in Six Mile and Lamonti creeks, although densities appear to be fairly low. Mountain Whitefish (70 to 330 mm) were caught in all four creeks. The sites sampled in Factor Ross and Ole creeks had greater numbers of Mountain Whitefish than did Six Mile and Lamonti creeks. Prickly Sculpin were present in all four study creeks. Neither Arctic Grayling nor sucker sp., which spawn in the spring when access tributaries can be impeded by perched mouths or debris jams, were observed in any of the study creeks. Arctic Grayling are not known to occur in any of the study creeks except for Six Mile (BC Ministry of Environment 2011), but are present in some of the larger tributaries of Williston (Cubberley and Hengeveld, 2010), and re-colonization of smaller tributaries may be possible, particularly if access enhancement is successful. The presence of large adult (likely spawners) and young-of-year Bull Trout in Ole Creek suggests that this species is successfully spawning in the creek. Failure to catch certain species in the study creeks during surveys in 2011 (e.g., Rainbow Trout not caught in Factor Ross or Ole creeks) should not be interpreted as absence of these species from the creeks. Our surveys sampled limited spatial area (two or three, 100 m sites per creek), and used only one capture method (i.e., backpack electrofishing), so it is likely that the species caught are not representative of the entire local fish community. The multiple-pass removal-depletion electrofishing survey used in this study provided baseline data about the species present in the study creeks, but failed to provide estimates of abundance of any species because of the very small number of fish caught. In addition, the method proved to be logistically challenging for the study creeks. Many sections of the creeks were characterized by fast riffle habitats, steep gradients, and/or large amounts of woody debris, which made installing block nets difficult (nets were torn or moved out of position by
Page 1 and 2: Peace Project Water Use Plan Willis
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Common Name Purple Finch Red-Breast
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APPENDIX F Fish Site Cards May 22,
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APPENDIX H Vegetation Survey Forms
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# File: WillstonTribsvs2.R APPENDIX
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Golder Associates Ltd. 220 - 1755 S
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GMSMON-17 WILLISTON RESERVOIR TRIBUTARY - BC Hydro

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