The Effects of Water Quality on the Growth Rate of Freshwater Mussels, Margaritifera falcata

By Jim Hashimoto

Background

This project is best suited for middle and high school students and can be adapted from a research project into an exploratory exercise. The viewfinders are easy to make using a 5 gallon plastic bucket with the bottom cut out. Plexiglas can be cut to fit and sealed with silicon cement. The viewfinders can also be used for viewing other aquatic macroinvertebrates. Additional materials that I found helpful in preparing this project were Field manual for Water Quality Monitoring by Mark K. Mitchell & William B. Stapp, and Aquatic Entomology, the Fisherman's and Ecologist's Illustrated Guide to Insects and Their Relatives by W. Patrick McCafferty.

Students requirement:

1. After receiving instruction, students will be able to conduct field research, document and process research data using the scientific method.

2. After receiving instructions on field test procedures, students will be able to use portable water test kits to conduct a series of water quality tests including dissolved oxygen, fecal coliform, BOD, nitrate, total phosphate, turbidity, total solids, pH, temperature and other related tests.

3. After conducting field research, students will be able to determine the best habitat requirements for optimal growth of freshwater mussels, Margaritifera falcata.

Preparation/Classroom Time needed:

In preparation for this field research, the students receive approximately two to four weeks of classroom instruction and training on stream ecology and mussel anatomy and physiology. They engage in water quality testing using samples from local streams. They also practice identifying various aquatic macroinvertebrates using taxonomic keys prior to going out in the field.

Activity

Students will participate in a field and laboratory study to determine if local freshwater mussels are environmentally stressed. Students will test the water quality of local streams/rivers using proper field techniques to determine the effects of water pollutants on the growth rate of freshwater mussels, margaritifera falcata. Freshwater mussels serve as our most sensitive indicators of water quality and ecosystem health and are considered to be among the most endangered animals. The student's research will be documented and forwarded to biologists and agencies involved in mussel studies in the Northwest.

Materials & Equipment:

• Portable Water Analysis Kits
• Portable View Finders: 5 gal. bucket, Plexiglas, silicon cement
• Tagging Equipment: Mesh/fish net bags, numerical tags, waterproof glue, knives
• Collecting jars/70% Alcohol
• D-Frame Nets/Kick Screen
• Waders/Gloves
• Life Jackets
• Data sheets for mussel observation and water analysis/macroinvertebrates
• Miscellaneous: Plastic rulers, clipboards, pencils
• First Aid Kit

Implementation:

1. Students will be introduced to the research project and the relationship between mussels and water quality, including basic anatomy and physiology of mussels, with special attention to methods of determining growth rate and life span. The students will also be introduced to the survey techniques used in testing water quality.

2. Students will construct a portable view finder for field research.

3. Students will be instructed in the use of topographical maps to research and evaluate what stream/river sites ought to be surveyed for mussel locale.

4. Students will travel to potential mussel sites for mussels using their portable view finders. Once sites have been located, students will perform the following tasks.
   1. Students will record information about the site on their mussel observation data sheet including location, drainage, description of water, and other relevant data.

   2. Students will make direct observations of mussels and record on mussel data sheet: description of mussel habitat, number of mussels in bed, individual coloration, size, etc., including sketches. Some older shells will be collected and their growth patterns analyzed at the lab under a stereoscope.

   3. Students will use their water analysis kits to conduct a series of tests for determining water quality of the sites. They will record the findings of the following tests on their water quality data sheet: dissolved oxygen, fecal coliform BOD, nitrate, total phosphate, tubidity, total solids, pH, temperature and other related test.

   4. Students will use their D-Frame nets and collecting jars to collect samples benthic macroinvertebrates for additional water quality assessment.

5. Students will return to the sites during the semester and perform the same tests. Data collected will be documented and forwarded to biologists and other agencies involved in mussel studies in the Northwest.

Method of Evaluation:

Fellows Collection Index

1996 AE Collection Index

Activities Exchange Index