SWAN Monitoring Freshwater Contaminants
Southwest Alaska Network. SWAN Monitoring Freshwater Contaminants. 2005. National Park Service
Resident (non-migratory) lake fish are key indicators of ecosystem health in southwest Alaska. They are also important to recreational and subsistence fisheries. Understanding their contaminant levels, therefore, is crucial. Many contaminants accumulate over time in fish tissue, especially in long-lived piscivorous species. When contaminant levels reach certain thresholds, fish consumption can be harmful and safety advisories can be issued for particular lakes or species. Consequently, elevated contaminant levels have human health ramifications, as well as broader ecological consequences. Since 2005, we have sampled more than 300 fish, representing 9 species from 18 lakes in 2 park units. These samples indicate that some resident lake fish species in southwest Alaska lakes have elevated concentrations of mercury, the majority of which is methylmercury, a potent neurotoxin. Why do these fish, which inhabit some of the most pristine and remote waters in North America, have such elevated mercury levels? And what accounts for differences in fish mercury levels among lakes? Factors driving fish mercury levels can be grouped into two broad categories: distant and local. Distant factors are atmospheric emissions (notably from coal burning), and subsequent long-range transport and deposition. Local factors influence the distribution of distantly derived mercury. Fish age and species also help determine mercury concentrations, in that older top predators tend to have higher concentrations. Understanding the interplay of each of these factors will help make sense of the observed pattern in the mercury levels of fish. Our monitoring objectives are to: Assess spatial differences in mercury contamination of resident lake fish. Evaluate temporal trends in mercury contamination of resident lake fish. Identify lakes where mercury contamination of resident lake fish may pose a risk to humans by surpassing accepted toxicological benchmarks. We monitor resident lake fish in four high priority lakes in Katmai and Lake Clark national parks and preserves.
- Type
- Project
- Authors
- Southwest Alaska Network
- Publisher
- National Park Service
- Units
- KATM , LACL , SWAN
- Keywords
- lake trout, mercury, resident lake fish
- Subjects
- Ecological Framework: Water | Water Quality | Toxics , Ecological Framework: Biological Integrity | Focal Species or Communities | Freshwater Communities , Ecological Framework: Biological Integrity | Focal Species or Communities | Fishes
Program
Products
- Protocol for monitoring mercury in resident lake fish - Version 1.0: Southwest Alaska Inventory and Monitoring Network
- Standard operating procedure 1: pre-season preparation version 1.0 in protocol for monitoring mercury in resident lake fish
- Standard operating procedure 2: training and safety version 1.0 in protocol for monitoring mercury in resident lake fish
- Standard operating procedure 3: field work version 1.0 in protocol for monitoring mercury in resident lake fish
- Standard operating procedure 4: data entry and management version 1.0 in protocol for monitoring mercury in resident lake fish
- Standard operating procedure 5: data analysis version 1.0 in protocol for monitoring mercury in resident lake fish
- Standard operating procedure 6: reporting version 1.0 in protocol for monitoring mercury in resident lake fish
- Standard operating procedure 7: post-season procedures version 1.0 in protocol for monitoring mercury in resident lake fish
- Standard operating procedure 8: protocol revision version 1.0 in protocol for monitoring mercury in resident lake fish
- Mercury Concentrations in Resident Lake Fish Sampled from Lake Clark National Park and Preserve in 2019 and 2020
- Drivers of mercury in top-predator lake fish from southwest Alaska parklands
- Freshwater Contaminants
- Resident Lake Fish
- Data quality standards for monitoring mercury in resident lake fish – Version 1.0: Southwest Alaska Inventory and Monitoring Network
- Understanding drivers of mercury in lake trout (Salvelinus namaycush), a top-predator fish in southwest Alaska's parklands
- Mercury Concentrations in Resident Lake Fish Sampled from Lake Clark National Park and Preserve in 2019 and 2020
- Mercury Concentrations in Resident Lake Fish Sampled from Katmai National Park and Preserve in 2021
- Elodea mediates juvenile salmon growth by altering physical structure in freshwater habitats
- Lake trout growth is sensitive to spring temperature in southwest Alaska lakes
- Freshwater Contaminants
- Resident lake fish
- Mercury in fishes: Lake Clark, Kontrashibuna Lake, and Telaquana Lake
- Resident Lake Fish - Contaminants
- Indicators of mercury concentration in Lake Trout: Can fish location and appearance provide information to anglers to reduce their exposure?
- Mercury Concentrations in Resident Lake Fish Sampled from Lake Clark National Park and Preserve (2019 and 2020) and Katmai National Park and Preserve (2021) — Data Package