Who Lives in the Water?
To investigate the diversity in a specific area through observation and charting.
In this lesson, students will investigate the diversity in a specific water body through
observation and charting. They will collect and observe macroinvertebrates in an aquatic
Discussion questions provide additional information to help students understand the importance of organisms in our water.
The lesson is designed in four parts:
- A classroom activity to familiarize students with the aquatic invertebrates they will be collecting;
- a field activity portion in which they will collect macroinvertebrates and observe them with the help of keys and photos (see tips on preparing for a water related activity to have a safe and meaningful experience);
- follow up STEM activities
- watershed connections.
1. Tell your students this activity will focus on the diversity of macroinvertebrates found in an aquatic ecosystem.
- Ask students to define the terms aquatic macroinvertebrate (an organism that is large enough to see with the naked eye and has no backbone) and diversity (the number of different species found in an area).
- Have students compare two different stream types (e.g. a small fast moving stream versus a large slow stream) and brainstorm what adaptations organisms would need to allow them to live in each environment. (see discussion question #3)
2. Review common macroinvertebrates found in your area. Make sure they are familiar with the keys they will be using in the field. Printable keys and online keys are available through USU Water Quality Extension.
3. Review instructions for sampling and sorting macroinvertebrates with your students before you go into the field. Follow the link below for step-by-step photos.
Prepare for Field Activity:
Proper preparation, before entering the field, is important to class safety. Follow the links below for tips for thorough preparation.
1. Set up easily accessible stations for sampling macroinvertebrates. Each station
should represent different conditions such as pebble, cobble, or silt, or different
flow conditions (running water or still backwater), or areas with leaf and woody debris. Have
each station include:
*Click here for information on purchasing equipment or supplies or creating your own equipment. Contact USU Water Quality Extension (email@example.com or 435-797-2580) for information on borrowing equipment
NOTE: If you are collecting chemistry data as well, make sure the macroinvertebrate station is downstream from the chemistry station.
2. Demonstrate how to safely collect samples with a kick net.
3. Divide students into groups and assign them to a sampling station. Have students
put samples into the plastic pans and sort invertebrates with transfer pipettes and
petri dishes following the instructions for sampling and sorting.
4. Have students record their results on the macroinvertebrate worksheet. Students can record individually or as a group.
NOTE: You can preserve macroinvertebrates in a glass vial or collection bottle filled with 70% alcohol and 30% water.
Students can further their understanding of macroinvertebrates as an indicator of water quality by looking at their data in various ways or participating in a variety of research projects. Some helpful ways to assist students in a better understanding are:
1. Use your data to create graphs or make comparisons.
- Calculate and graph the diversity (number of different types of organisms) in each area sampled.
- Sample other waterbodies or multiple locations along a single river or stream and compare results
- Sample the same stations on multiple dates and compare results.
- Use other types of sampling equipment (e.g. Hester-Dendy sampler) and compare results.
2. Discuss what their results mean (see discussion questions for this exercise).
- Research factors that would contribute to a decline in the diversity of macroinvertebrates.
What watershed do you live in?
You can find information for each watershed here:
Curriculum and Teacher Materials
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