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Pine Creek Passage Follow UpThe ARRC is committed to completing the necessary follow up monitoring and review of the arctic grayling habitat enhancement that was completed in 2019.
The 2024 follow up work will be conducted in August 2024. |
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Work Completed To DateThe Alsek Renewable Resources Council (ARRC) worked with EDI to develop a small research project during 2016 to answer questions about the current status of Arctic grayling fish passage and distribution within Pine Creek. Arctic grayling have been documented in Pine Creek, although little is known about their life history and specifically if there are adult or juvenile migrations between Pine Lake, Pine Creek, and/or the Dezadeash River. The 2016 project included three components: (1) a desktop review of existing information on Arctic grayling presence in the Pine Creek watershed, (2) field investigations (including fish sampling) in May and September, and (3) interviews with knowledgeable locals about historical fish and fish habitat values in Pine Creek. The results of the 2016 field investigations indicated that there were currently no barriers to upstream fish passage in Pine Creek between the Alaska Highway crossing and Pine Lake. Fish sampling conducted during May and September 2016 indicate that there is a resident population of Arctic grayling in Pine Creek; however, the abundance of fish is relatively low compared to other Yukon populations and productive capacity appears to be limited by a lack of high-quality habitat.
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Results of the interviews with local individuals indicate that Pine Creek had good fishing for Arctic grayling up until approximately 1980 after which the quality of fishing declined considerably. This decline in fishing success occurred shortly after the raising of water levels on Pine Lake for other recreational interests and the subsequent installation of culverts at the outlet of the lake. Although there is a correlation between these two events, it cannot be concluded with certainty that other factors such as harvest pressure or other habitat changes did not contribute to the decline of the fishery.
This project continued during 2017 and included three main objectives; (1) conduct follow up field assessments and fish sampling to add to the existing information on Arctic grayling presence in Pine Creek, (2) identify potential fish habitat improvement sites in Pine Creek, (3) conduct an operation trial at a small number of fish habitat improvement sites and collect appropriate biological and physical monitoring data at each site. The 2017 field program involved investigations during the spring and late summer and a number of potential sites were identified for habitat enhancement through the creation of stream channel complexity (cover). Biological monitoring was conducted using three-pass depletion electrofishing to obtain a density of
Arctic grayling at each improvement site (before improvement) and a control site. Physical monitoring was conducted prior to the improvement works (thalweg and cross section profiles) to allow for changes to the
channel characteristics to be monitored over time.
The 2018 field program built on knowledge, data and experience gained in the previous years to add more
enhancement sites to Pine Creek. A field investigation was conducted during May 2018 to add to existing
knowledge and data collected during the 2016 and 2017 projects. Fish sampling was completed, potential
barriers to fish passage investigated, and candidate sites for instream habitat improvement were identified
between the Alaska Highway crossing and the Pine Lake outlet based on candidate sites identified during the 2017 field program. During August 2018, five sites were selected for additional habitat enhancement trials.
Once again, logs and/or rocks were used to increase pool depth, pool cover, and instream habitat complexity.
Consistent with 2017, biological monitoring was conducted using three pass depletion electrofishing to obtain a density of Arctic grayling at each site prior to the construction of habitat enhancement structures. Physical monitoring was conducted prior to habitat enhancement work (thalweg and cross section profiles) to allow for changes to channel characteristics to be monitored over time. Habitat enhancement trails started in 2017 and 2018 are intended to encourage the presence of adult Arctic grayling in Pine Creek by increasing stream complexity and the amount of quality holding and rearing habitat.
In 2019 the field program continued to build upon the knowledge, data, and experience gained in the previous
years. Consistent with 2017 and 2018, biological monitoring was conducted at 2018 habitat enhancement sites and control sites using three pass depletion electrofishing to obtain a density of Arctic grayling at each site shortly after the construction of habitat enhancement structures. Physical monitoring was conducted at to habitat enhancement sites including thalweg and cross section profiles to reflect changes to channel characteristics post habitat enhancement. Habitat enhancement trails started in 2017 and 2018 are intended to encourage the presence of adult Arctic grayling in Pine Creek by increasing stream complexity and the amount of quality holding and rearing habitat.
This project continued during 2017 and included three main objectives; (1) conduct follow up field assessments and fish sampling to add to the existing information on Arctic grayling presence in Pine Creek, (2) identify potential fish habitat improvement sites in Pine Creek, (3) conduct an operation trial at a small number of fish habitat improvement sites and collect appropriate biological and physical monitoring data at each site. The 2017 field program involved investigations during the spring and late summer and a number of potential sites were identified for habitat enhancement through the creation of stream channel complexity (cover). Biological monitoring was conducted using three-pass depletion electrofishing to obtain a density of
Arctic grayling at each improvement site (before improvement) and a control site. Physical monitoring was conducted prior to the improvement works (thalweg and cross section profiles) to allow for changes to the
channel characteristics to be monitored over time.
The 2018 field program built on knowledge, data and experience gained in the previous years to add more
enhancement sites to Pine Creek. A field investigation was conducted during May 2018 to add to existing
knowledge and data collected during the 2016 and 2017 projects. Fish sampling was completed, potential
barriers to fish passage investigated, and candidate sites for instream habitat improvement were identified
between the Alaska Highway crossing and the Pine Lake outlet based on candidate sites identified during the 2017 field program. During August 2018, five sites were selected for additional habitat enhancement trials.
Once again, logs and/or rocks were used to increase pool depth, pool cover, and instream habitat complexity.
Consistent with 2017, biological monitoring was conducted using three pass depletion electrofishing to obtain a density of Arctic grayling at each site prior to the construction of habitat enhancement structures. Physical monitoring was conducted prior to habitat enhancement work (thalweg and cross section profiles) to allow for changes to channel characteristics to be monitored over time. Habitat enhancement trails started in 2017 and 2018 are intended to encourage the presence of adult Arctic grayling in Pine Creek by increasing stream complexity and the amount of quality holding and rearing habitat.
In 2019 the field program continued to build upon the knowledge, data, and experience gained in the previous
years. Consistent with 2017 and 2018, biological monitoring was conducted at 2018 habitat enhancement sites and control sites using three pass depletion electrofishing to obtain a density of Arctic grayling at each site shortly after the construction of habitat enhancement structures. Physical monitoring was conducted at to habitat enhancement sites including thalweg and cross section profiles to reflect changes to channel characteristics post habitat enhancement. Habitat enhancement trails started in 2017 and 2018 are intended to encourage the presence of adult Arctic grayling in Pine Creek by increasing stream complexity and the amount of quality holding and rearing habitat.
Project Objectives 2024The objectives of the project include the following:
1. Visually inspect and document the condition of all 8 enhancement sites to determine the stability and longevity of different structures and make sure they have not shifted excessively and are allowing for fish passage. 2. Collect site and drone photographs of all 8 enhancement sites to determine changes over time. 3. Complete open cell single pass electrofishing and/or angling for at least half (four) habitat enhancement sites constructed in 2017 and 2018 and compare to nearby control areas. |
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