Limnological and fishery investigations concerning Sockeye Salmon production in Delight and Desire Lakes. Final Report
Edmundson JA, Dickson M, Bucher WA. 2001. Limnological and fishery investigations concerning Sockeye Salmon production in Delight and Desire Lakes. Final Report. Exxon Valdez oil spill restoration project final report. Restoration Project 97254. Alaska Department of Fish And Game, Division of Commercial Fisheries. Soldotna, Alaska
The 1989 Exxon Vuldez oil spill contaminated the waters of Nuka Bay, and light oiling was observed near the outlets of Delight and Desire Lakes. Although there is no direct evidence that the spill affected sockeye salmon production, commercial catches of sockeye in the East Nuka Bay subdistrict averaged 7,300 after the spill compared to 29,800 prior to the spill. Results from limnological surveys carried out in 1997 revealed that both lakes are nutrient poor (mean total phosphorus concentration 5 pg L-‘) and have low chlorophyll levels and low zooplankton densities. Zooplankton biomass was very low in both lakes and six times less in Desire Lake (mean 17 mg m”) compared to Delight Lake (mean 102 mg m”). Age-l smolt (the predominant age class in both lakes) production in Desire Lake (76,353) in 1997 was only about one-sixth that of Delight Lake (468,184), yet the brood-year (1995) escapement was estimated to be the same for both lakes (15,000) suggesting a smaller rearing capacity in Desire Lake compared to Delight Lake. Based on the 1997 weir estimate of sockeye escapements and observations of spawning activity in the two lakes, we speculate that aerial surveys underestimated Delight Lake escapements in past years.
- Type
- Published Report
- Authors
- Edmundson, Jim; Dickson, Mark; Bucher, Wesley
- Date of Issue
- 2001-06
- Publisher
- Alaska Department of Fish And Game, Division of Commercial Fisheries
- Units
- KEFJ , SWAN
- Keywords
- East Nuka Bay, Limnology, lower Cook Inlet, Nutrient Enrichment, sockeye salmon smolts