- Designed for the NYC and NYC Watersheds Trout in the Classroom program. Can be adapted to any classroom!
- Created by Veronica Rowe, TIC Teacher.
Students will observe the differences between a variety of species of aquatic macroinvertebrates living in coldwater streams and identify their place in the food web.
The cool, cold and well-protected Catskill Mountain streams attract fly fishers from across the country who come to fish for brook and brown trout in a natural habitat. These anglers use fake fishing-flies that mimic bugs as their lures or bait to catch the fish. Fly fishers are often most successful when their fishing flies look similar to local aquatic macroinvertebrate species which present at the same time that they are.
Aquatic macroinvertebrates (such as insect larvae, mollusks, and crustaceans) are a large part of a trout’s diet. The flying adult forms of some aquatic insects are also food for trout. Different species of invertebrates have different characteristics, including body shape (morphology), exoskeleton color, feeding preferences, in-stream behaviors, etc. You can see images and find out more about aquatic macroinvertebrates at the NYSDEC Key to Aquatic Macroinvertebrates.
Fly anglers fish by using hooks (“flies”) that imitate a trout’s favorite foods, rather than by holding bait. To make these flies, anglers study closely the species they are imitating, and then wrap barbless hooks with thread, feathers, and other materials of various colors. This activity encourages your students to take a close look at aquatic macroinvertebrates, and will especially engage kinesthetic learners and young artists in the science of fly-tying. If you have a member of TU nearby who is willing to come this class to share their experience, that person could be a great resource for this lesson.
- Images or specimens of local aquatic macroinvertebrates and their flying adult counterparts
- Actual flyfishing flies
- Chenille stems
- Other craft supplies in various colors
- Tape or glue
In small groups or as a whole class, have students look at images, photographs, and/or specimens of different species of aquatic macroinvertebrates. (Older students can do this research themselves) As they look, ask students to identify and notice differences and similarities between species. What do they see? Explain to students that different macroinvertebrates have different adaptations (colors, gill placement, mouthparts, etc.), and ask them to imagine being a trout and trying to tell the different types of macroinvertebrates apart. Take a look at some real fly fishing flies and images of the species they represent. Have students notice the similarities and differences between the two. Then, allow them a close look at the flies, to see the wrapping technique, and to see what kind of materials were used for different body parts, such as the wings, legs, etc. Give each student a chenille stem and access to all the other craft supplies. After having them bend the chenille stem into a hook shape that is at least three inches long, ask them to choose one type of macroinvertebrate to model their design on.
Ask students to share their flies, explaining to the class which distinct features they added to their design to make it resemble a certain species. Students might also explain other adaptations they imagine their macroinvertebrate might have.