Distribution and characteristics of Sockeye Salmon, spawning habitats in the Lake Clark Watershed, Alaska
Dates
Year
2005
Citation
Young, Daniel, 2005, Distribution and characteristics of Sockeye Salmon, spawning habitats in the Lake Clark Watershed, Alaska: National Park Service Water Resources Division, v. Technical Report/NPS/NRWRD/NRTR-2005/338, 29 Pages.
Summary
This report describes findings from a sockeye salmon Oncorhynchus nerka radio telemetry and spawning habitat study conducted in the Lake Clark watershed in 2000 and 2001. The primary objectives of this research were 1) to locate and map all major spawning aggregations 2) to determine basic characteristics of spawning habitats, and 3) to determine the distribution of private land uses and subsistence/sport use locations in relation to salmon spawning habitats. To determine spawning distributions, 332 adult sockeye salmon were radio tagged as they entered Lake Clark in 2000 and 2001. Fish were relocated every 1-10 days by boat, plane, or remote solar powered receiver. On average, a radio tagged fish was relocated 12.7 times (range, 3 [...]
Summary
This report describes findings from a sockeye salmon Oncorhynchus nerka radio telemetry and spawning habitat study conducted in the Lake Clark watershed in 2000 and 2001. The primary objectives of this research were 1) to locate and map all major spawning aggregations 2) to determine basic characteristics of spawning habitats, and 3) to determine the distribution of private land uses and subsistence/sport use locations in relation to salmon spawning habitats. To determine spawning distributions, 332 adult sockeye salmon were radio tagged as they entered Lake Clark in 2000 and 2001. Fish were relocated every 1-10 days by boat, plane, or remote solar powered receiver. On average, a radio tagged fish was relocated 12.7 times (range, 3 - 33) and over 3,500 relocations were made. Thirty-five spawning areas were identified, including three sites downstream of the tagging area and five sites identified by visual observation or seining. Eighteen areas were newly identified. Most Lake Clark sockeye salmon spawn in the Tlikakila River, Kijik watershed and along beaches of Lake Clark and Little Lake Clark. Spawning habitat locations were mapped into the Geographic Information System (GIS) for Lake Clark National Park and Preserve. Surprisingly, over 60% of radio tagged salmon spawned in turbid glacial waters; most of which were adjacent to an obvious clear water source. Sockeye salmon spawning habitat was examined from a subset of spawning sites identified by radio telemetry. Basic characteristics including water temperature, turbidity, water depth, channel width, slope, and spawning substrate were collected. Water quality data were collected from the outlet of spawning tributaries during a concurrent study (Brabets 2002). Surface water temperature at spawning habitats ranged from 3.1° Celsius (C) to 12.9° C. Habitats in the glacier-fed Currant Creek and Tlikakila River as well as the spring-fed Priest Rock Creek were cooler than other habitats. Spawning habitats in the upper portion of the watershed were turbid due to runoff from glacial melt. However, the timing of spawning activity in turbid habitats coincided with a dramatic decrease in the concentration of suspended sediment and turbidity. Tributary spawning habitats were in less than one meter of water and spawning channels were on average less than 50 meters in width. Spawning substrate was variable among sites and ranged from habitat dominated by small fines in the headwaters of Tlikakila River to boulder dominated habitat in Little Lake Clark and Sucker Bay Lake. Water quality parameters were all within acceptable range for freshwater aquatic life. Subsistence and sport fishing data were summarized using data collected during previous studies and by National Park Service (NPS) staff. Existing GIS coverages of land ownership were used to compare the location of spawning habitats relative to land ownership. Current development within the Lake Clark watershed was documented by NPS staff. Subsistence fishing for migrating sockeye salmon occurs throughout Lake Clark near seasonal and year-round residences. Residents of Nondalton harvest red fish (spawning sockeye salmon) from spawning areas. Sport harvest occurs at the outlet of Lake Clark, the outlet of Tanalian River, and within the Kijik Lake drainage. Subsistence and sport fishers currently harvest less than one percent of the Lake Clark escapement. About 75% of identified spawning habitats are adjacent to privately owned lands, many slated for development. Proactive measures should be taken to conserve these habitats.