Common use of Stehekin River Mainstem Westslope Cutthroat and Rainbow Trout Surveys, NPS Clause in Contracts

Stehekin River Mainstem Westslope Cutthroat and Rainbow Trout Surveys, NPS. Despite the apparent lack of spawning WCT in Stehekin River tributary and side channel index sites, a number of large (380-460 mm) WCT were viewed in the mainstem Stehekin River during the autumn 2010 kokanee surveys. Though not observed while spawning, these observations confirm the presence of large, potentially adfluvial WCT in the Stehekin River system. In light of these observations in 2011 it was decided to refocus our efforts to include distribution and abundance surveys of trout during the late summer and early fall during low flow periods. The objectives of these surveys were to gain a better understanding of adfluvial WCT abundance and distribution in the Stehekin River system and to assess management activities designed to increase the WCT population and reduce the population of non-native XXX. Eight large channel spanning pools were initially identified in the lower 7 km of the mainstem Stehekin River which were surveyed once in the early spring, and twice in the late summer/ early fall of 2011. Six of the eight pools located in 2011 were selected for continued surveys from 2012 to 2014. Pool selection was based on documented WCT presence and safety of conducting snorkel surveys under elevated flow conditions. Survey methods and pool location maps were included in the 2009-2011 spawning survey report (Xxxxxxx and Xxxxxx 2012) while a comprehensive report covering 2011-2014 mainstem pool results will be completed in the spring of 2015. Snorkel surveys were conducted by teams of two, with one surveyor counting fish and one surveyor on the channel bank timing the snorkel pass and recording data. Fish were tallied into length groups of less than 150 mm, 150–299 mm, 300–449 mm, and ≥450 mm. Each pool was snorkeled three times and the number of fish observed by species and observation time was recorded for each pass. Results are outlined in Table 13 below. Table 13: Number of greater than six inch trout observed and size classes within six mainstem pool index sites, 2011 – 2013. Number of fish observed Westslope Cutthroat Trout Rainbow Trout Eastern Xxxxx Xxxxx Survey Date 150-299 mm 300-449 mm ≥450 mm 150-299 mm 300-449 mm ≥450 mm 150-299 mm 300-449 mm ≥450 mm 8/2/2011 3 1 0 10 3 0 0 0 0 8/30/2011 0 2 0 11 4 0 0 0 0 8/15/2013 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 9/18/2013 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 1 - Due to intense rainfall and high river turbidity surveys were not completed on these dates. In 2012 and 2013, North Cascades National Park Biologists conducted exploratory snorkel surveys on two reaches of mainstem xxxxxx habitat to assess the possibility of including this habitat in long term monitoring for WCT presence (Table 14). NPS biologists found that while inclusion of these mainstem xxxxxx sites in late summer abundance surveys may be worthwhile, mainstem surveys would be difficult to perform under flows greater than 2000 cfs and thus not possible during much of the spring spawning season. If these surveys are conducted during the spring spawning period it is recommended that they be performed on the first survey date to take advantage of late winter low flow conditions. Table 14: Number of greater than six inch fish observed and size classes within two mainstem xxxxxx sites, 2012 – 2013. Number of fish observed Survey Date Site Name Westslope Cutthroat Trout Rainbow Trout Kokanee 9/18/2013 Blackberry N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 1 - Due to intense rainfall and high river turbidity surveys were not completed on these dates.

Stehekin River Mainstem Westslope Cutthroat and Rainbow Trout Surveys, NPS. Despite the apparent lack of spawning WCT in Stehekin River tributary and side channel index sitessites (Section 2.2.3.), a number of large (380-460 mm) WCT were viewed in the mainstem Stehekin River during the autumn 2010 kokanee surveys. Though not observed while spawning, these observations confirm the presence of large, potentially adfluvial WCT in the Stehekin River system. In light of these observations in 2011 it was decided to refocus our efforts to include distribution and abundance surveys of trout during the late summer and early fall during low flow periods. The objectives of these surveys were to gain a better understanding of adfluvial WCT abundance and distribution in the Stehekin River system and to assess for assessing progress towards restoration of these fish and evaluating management activities designed to increase the WCT population and reduce the population efforts directed at reduction of non-native XXX. Eight large channel spanning pools were initially identified in the lower 7 km of the mainstem Stehekin River which were surveyed once in the early spring, and twice in the late summer/ early fall of 2011. Six of the eight pools located in 2011 were selected for continued surveys from 2012 to 2014. Pool selection was based on documented WCT presence and safety of conducting snorkel surveys under elevated flow conditionswithin the pool. Survey methods and pool location maps were included in the 2009-2011 spawning survey report (Xxxxxxx and Xxxxxx 2012) while a comprehensive report covering 2011-2014 mainstem pool results will be completed in the spring of 2015. Snorkel surveys were conducted by teams of two, with one surveyor counting fish and one surveyor on the channel bank timing the snorkel pass and recording data. Fish were tallied into length groups of less than 150 mm, 150–299 mm, 300–449 mm, and ≥450 mm. Each pool was snorkeled three times and the number of fish observed by species and observation time was recorded for each pass. Results are outlined in Table 13 below. Table 13: Number of greater than six inch trout observed and size classes within six mainstem pool index sites, 2011 – 2013. Number of fish observed Westslope Cutthroat Trout Rainbow Trout Eastern Xxxxx Xxxxx Survey Date 150-299 mm 300-449 mm ≥450 mm 150-299 mm 300-449 mm ≥450 mm 150-299 mm 300-449 mm ≥450 mm 8/2/2011 3 1 0 10 3 0 0 0 0 8/30/2011 0 2 0 11 4 0 0 0 0 8/15/2013 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 9/18/2013 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 1 - Due to intense rainfall and high river turbidity surveys were not completed on these dates. In 2012 and 2013, North Cascades National Park Biologists conducted exploratory snorkel surveys on two reaches of mainstem xxxxxx habitat to assess the possibility of including this habitat in long term monitoring for WCT presence (Table 14). NPS biologists found that while inclusion of these mainstem xxxxxx sites in late summer abundance surveys may be worthwhile, mainstem surveys would be difficult to perform under flows greater than 2000 cfs and thus not possible during much of the spring spawning season. If these surveys are conducted during the spring spawning period it is recommended that they be performed on the first survey date to take advantage of late winter low flow conditions. Table 14: Number of greater than six inch fish observed and size classes within two mainstem xxxxxx sites, 2012 – 2013. Number of fish observed Survey Date Site Name Westslope Cutthroat Trout Rainbow Trout Kokanee 9/18/2013 Blackberry N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 1 - Due to intense rainfall and high river turbidity surveys were not completed on these dates.

Stehekin River Mainstem Westslope Cutthroat and Rainbow Trout Surveys, NPS. Despite the apparent lack of spawning WCT in Stehekin River tributary and side channel index sites, a number of large (380-460 mm) WCT were viewed in the mainstem Stehekin River during the autumn 2010 2010-kokanee surveys. Though not observed while spawning, these observations confirm the presence of large, potentially adfluvial WCT in the Stehekin River system. In light of these observations in 2011 2011, it was decided to refocus our efforts to include distribution and abundance surveys of trout during the late summer and early fall during low flow periods. The objectives of these surveys were to gain a better understanding of adfluvial WCT abundance and distribution in the Stehekin River system and to assess management activities designed to increase the WCT population and reduce the population of non-native XXX. Eight large channel channel-spanning pools were initially identified in the lower 7 km of the mainstem Stehekin River River, which were surveyed once in the early spring, and twice in the late summer/ early fall of 2011. Six of the eight pools located in 2011 were selected for continued surveys from 2012 to 2014. Pool selection was based on documented WCT presence and safety of conducting snorkel surveys under elevated flow conditions. Survey methods and pool location maps were included in the 2009-2011 spawning survey report (Xxxxxxx and Xxxxxx 2012) while a comprehensive report covering 2011-2014 mainstem pool results will be completed in the spring of 2015. Snorkel surveys were conducted by teams of two, with one surveyor counting fish and one surveyor on the channel bank timing the snorkel pass and recording data. Fish were tallied into length groups of less than 150 mm, 150–299 mm, 300–449 mm, and ≥450 mm. Each pool was snorkeled three times and the number of fish observed by species and observation time pass duration was recorded recorded. Of the three snorkel passes, the maximum fish count for each pass. Results are species was compared by date of survey as outlined in Table 13 Figure 3 below. Table 13Figure 3: Number Maximum Count of greater Greater than six inch trout observed and size classes Six-Inch Trout Observed within six mainstem pool index sitesSix Mainstem Pool Index Sites, 2011 – 2013. Number of fish observed Westslope Cutthroat Trout Rainbow Trout Eastern Xxxxx Xxxxx Survey Date 150-299 mm 300-449 mm ≥450 mm 150-299 mm 300-449 mm ≥450 mm 150-299 mm 300-449 mm ≥450 mm 8/2/2011 3 1 0 10 3 0 0 0 0 8/30/2011 0 2 0 11 4 0 0 0 0 8/15/2013 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 9/18/2013 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 1 - Due to intense rainfall and high river turbidity surveys were not completed on these dates. 2014 In 2012 and 2013- 2014, North Cascades National Park Biologists conducted exploratory snorkel surveys on two reaches of mainstem xxxxxx habitat to assess the possibility of including this habitat in long term monitoring for WCT presence (Table 1413). NPS biologists found that while inclusion of these mainstem xxxxxx sites in late summer abundance surveys may be worthwhile, mainstem xxxxxx surveys would be difficult to perform under flows greater than 2000 cfs and thus not possible feasible during much of the spring spawning season. If these These exploratory surveys are conducted during the spring spawning period it is recommended that they will be performed on the first survey date to take advantage of late winter low flow conditionsdiscontinued in 2015. Table 1413: Number of greater Greater than six inch fish observed Six-Inch Fish Observed and size classes Size Classes within two mainstem xxxxxx sitesTwo Mainstem Xxxxxx Sites, 2012 – 2013. 2014 Number of fish observed Survey Date Site Name Westslope Cutthroat Trout Rainbow Trout Kokanee 9/18/2013 10/8/2014 Blackberry N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 N/A1 1 - Due to intense rainfall and high river turbidity surveys were not completed on these dates.