Why Biomonitor Using Aquatic Macroinvertebrates to Monitor Stream
Why Biomonitor? Using Aquatic Macroinvertebrates to Monitor Stream Health
Biological Background on Biomonitoring: What is biomonitoring? • Using living species to determine the health of a system • Examples: • 300 BC Aristotle uses fish • Kings’ wine and food tasters • Canaries in the coal mine • 1972 Clean Water Act mandate to restore and protect the chemical, physical, and biological integrity of the nation’s waters
What are macroinvertebrates? Large visible, bottom dwelling aquatic organism (insects, snails, worms, clams, crustaceans) that DO NOT have a internal skeletal structure
Roles of Macroinvertebrates: • Pollinators • Decomposers • Shredders • Filterers • Scrapers • Predators • Foodchain • Pests
Reasons to Use Macroinvertebrates as Biomonitors in the Pacific Northwest
Stonefly-intolerant Blackfly-tolerant • How are macroinvertebrates a reliable indicator of water quality? • Aquatic macroinvertebrates differ in their sensitivity to water pollution —meaning some are pollution tolerant, while others are pollution intolerant • Aquatic macro’s provide information about the quality of a stream over long periods of time (videotape vs snapshot) • Easy to collect • Sedentary, so they stay put which allows them to experience present water quality conditions
Complete Metamorphosis Examples: Beetle, butterflies, moths, bees, black fly, mosquitos
Incomplete Metamorphosis Examples: Stone flies, caddis flies, dragon flies, grass hoppers
When do we monitor?
Fall: • Less impact on salmon • Low flows-easier/safer access • Concentrated populations of macros • Degraded sites become apparently degraded while pristine sites remai intact
Review 1. What is meant by biomonitoring? 2. Discuss the historical use of biomonitoring. 3. When do you sample and why? 4. How are aquatic macroinvertebrates a reliable indicator of water quality? 5. What important roles do macroinvertebrates play in the ecosystem? 6. Define macroinvertebrates
- Slides: 11