Bull Trout. The LCFF believes that the monitoring of any future population and/or individual occurrences of bull trout in Lake Chelan should be an important component to the monitoring and evaluation program. Monitoring of this species at this time should include documentation of incidental occurrences during associated fish monitoring and evaluation program activities. Standard metric measurements, physical condition, photographs, and location of fish within Lake Chelan during these occurrences should be documented and provided to the LCFF for review. The USFWS prepared the paper entitled “What happened to bull trout in Lake Chelan? An examination of the historical evidence” (Xxxxxx 2012). The intent of the document was to conduct a “…rigorous examination of the factors that may have lead to the demise of bull trout” prior to considering any reintroduction of bull trout into the Lake Chelan basin. This is a very important management document and is included by reference into the AWP.
Bull Trout. The LCFF believes that the monitoring of any future population and/or individual occurrences of bull trout in Lake Chelan should be an important component to the monitoring and evaluation program. Monitoring of this species at this time should include documentation of incidental occurrences during associated fish monitoring and evaluation program activities. Standard metric measurements, physical condition, and location of fish within Lake Chelan during these occurrences should be documented and provided to the LCFF for review.
Bull Trout. The LCFF believes that the monitoring of any future population and/or individual occurrences of bull trout in Lake Chelan should be an important component to the monitoring and evaluation program. Monitoring of this species at this time should include documentation of incidental occurrences during associated fish monitoring and evaluation program activities. Standard metric measurements, physical condition, photographs, and location of fish within Lake Chelan during these occurrences should be documented and provided to the LCFF for review. The USFWS prepared the paper entitled “What Happened to Bull Trout in Lake Chelan? An Examination of the Historical Evidence” (Xxxxxx 2012). The intent of the document was to conduct a “…rigorous examination of the factors that may have led to the demise of bull trout” prior to considering any reintroduction of bull trout into the Lake Chelan basin. This is a very important management document that should be included by reference into the AWP. In 2016, the NPS conducted environmental DNA (xXXX) sampling of a large part of the Stehekin River watershed to determine presence or absence of Bull Trout. This survey was conducted as part of the USFS Rocky Mountain Research Station Columbia Basin Bull Trout Initiative. The Stehekin River and its major tributaries were sampled according to protocols established by Carim et al, (2015), with sample sites located every 1 km throughout sample streams. A total of 152 sites in the Stehekin Basin were targeted by the NPS for sampling, and in 2016, 124 sites were surveyed. In 2017, the NPS intends to complete sampling of the remaining 28 sample sites. This survey will provide another piece of evidence in determining if Bull Trout have indeed been extirpated from the Stehekin River basin.
Bull Trout. Bull Trout exhibited generally balanced upstream and downstream movements throughout the Peace River in April through October, with decreased movements recorded through the winter months (Figure 13A). Some tagged Bull Trout appear more likely to move downstream in September and October before winter, with counterpart upstream movements in April and May. A decrease in activity appears ubiquitous throughout winter months, although much of the array is offline during this period, which decreases the certainty of that generalization. Primary tributary movements by Bull Trout were recorded in the Halfway River, with entrance behaviours occurring between April and September with a small spike occurring in May and exit behaviours largely occurring in September and October (Figure 13B)50. Following entrance into the Halfway River, Bull Trout are proceeding upstream in July, August, and September with downstream behaviours largely occurring in September and October, following spawning. Entrance and exit behaviours were also analyzed and displayed for the Pine River (Figure 13B), which is recognized as a secondary spawning river system to the Halfway River (Mainstem Aquatics 2012, Geraldes and Xxxxxx 2020). Study Bull Trout exhibited entrance and exit behaviours in the Pine River primarily in and around the month of September which may be indicative of spawning behaviour. However, without additional upstream fixed-stations and/or mobile tracking efforts in the Pine River these behaviours can not be validated. Similar to Arctic Grayling, Bull Trout exhibited entrance and exit behaviours in lower quantities at numerous other tributaries (e.g., Xxxxxxx Xxxxx, Xxxxxxx Creek, Xxxxxxx River, Beatton River, and Kiskatinaw River) throughout the study period, and for shorter residences, which is indicative of non-significant movement behaviours. 50 Note that any study fish transported and released into the Halfway River (i.e., the Halfway River Boat Launch) were removed from this analysis to avoid bias from these activities. Figure 12A. Mean movements (in RKM), by month, for Arctic Grayling in the Peace River and Xxxxxxx River, calculated from all data collected 2019 through 2021. Positive values refer to upstream movement, and negative values refer to downstream movement. Error bars show the 95% confidence limits. Continues A-F Figure 12B. Tributary entrance and exit movements for Arctic Grayling, tallied per individual study fish by month. Figure 13A. Bull Trout mean month...
Bull Trout. In 2021, a total of 26 adult Bull Trout exhibited spawning behaviours in the Halfway River and its tributaries (Figures 19, E2, and E3). Of the 26 Bull Trout that exhibited spawning behaviours in 2021, 11 were released directly into the Halfway River (i.e., the Halfway River Boat Launch) between 22 April and 31 August 2021 which likely affected normal entrance behaviours53. Therefore, these fish were culled when calculating Bull Trout entrance timing into the Halfway River. The median Bull Trout entered the Halfway River on 15 July 2021 (range = 21 April to 18 September 2021) and exited on 27 September 2021 (range = 20 September to 4 November 2021; Table 12). The wide range in Bull Trout entrance timing from 2021 was also reported in 2020 with Bull Trout entering between 26 April and 17 July 2020 (Hatch et al. 2021). Furthermore, exit timing was also similar to the 2020 results: ranging between 6 September and 7 October 2020. 53 Among these 11 Butt Trout, six were captured downstream of Site C, radio-tagged and released into the Halfway River between 22 April and 13 May 2021. One was captured in the TUF on 18 August 2021, radio-tagged and then released into the Halfway River. Two were captured in the TUF and re-released into the Halfway River in August 2021 while the remaining two were captured downstream of Site C by contingent electrofishing and re-released into the Halfway River in July 2021. Halfway River Cypress Creek Chowade River
