From 2006 to 2014, twice a summer, in June and again in August, Inletkeeper staff trained citizen scientists to collect, identify, and record the abundance and diversity of aquatic insects in a selection of our monitoring streams. The numbers and types of aquatic insects, affectionately referred to as ‘bugs’, in our streams can tell us a great deal about water quality. We use these data, along with our citizen-collected water chemistry data, to look at changes and trends in water quality over time within the Kachemak Bay and Anchor River watersheds.
Macroinvertebrates (insects and other invertebrates that can be seen with the naked eye) are well suited for monitoring studies due to their abundance, diversity, and relative ease to sample and analyze. In most streams, the macroinvertebrate community is dominated by larval insects which live a completely aquatic existence, feeding on organic matter like fallen leaves and other invertebrates. Each insect group has specific requirements for food, substrate, temperature, and dissolved oxygen concentrations. The presence or absence of particular insects is a good indicator of certain water quality and habitat conditions.
This kind of monitoring is termed "biological assessment" - an evaluation of streams using biological surveys. The use of indicator species helps to characterize the current status of the biological condition in a watershed. Mayflies (Ephemeroptera), stoneflies (Plecoptera), and caddisflies (Trichoptera) are referred to as EPTs and are considered the key indicator species of stream health. These types of insects do not tolerate pollution, and you won't find them in streams that have poor habitat or water quality. These three groups are found in most streams in Alaska. In 2003, Cook Inletkeeper began incorporating EPA Rapid Bioassessment Protocols, refined for use in Alaska by the Environment and Natural Resources Institute (ENRI) at University of Alaska Anchorage, into our citizen-based water quality monitoring program.
Each one of Inletkeeper's Citzens' Environmental Monitoring Program annual water quality report includes a review of the previous years' biological assessment, and all baseline water quality reports for monitoring sites review the full set of bioassessment data, if it's available for that site.