Fish Finders

Engagement

30-40 minutes

Ask students to recall the freshwater stages of a salmon’s life cycle. Write the stages (eggs, alevin, fry, smolt, adult, spawner) as headings on the board, then write “need” after each one and have students list the basic needs for each life cycle stage. You may also provide a blank Salmon Needs Chart for students to complete. They can use the completed chart as a reference on the field trip.

Introduce the term “habitat” and remind students that habitat includes food, air, water, and shelter.
To help prompt students for responses, you might answer the following questions about each stage:

• Where does it live (freshwater or saltwater?)
• Does it have special needs to live here? (gravel, rocks, plants, etc for protection)
• What dangers are present at this life stage? (predators, human impacts, etc)
• What does it eat?
• What is special about it at this stage that allows it to live in the place that it does?
• Are there any other interesting facts that should be noted at this stage?

If students don’t mention air as a need, this is a good time to discuss the concept of oxygen in the water. Salmon need water that is rich in oxygen to remain healthy, especially in the life cycle stages that take place in freshwater. Water that moves rapidly across rocks and boulders causes the air to mix with the water. The salmon take in the dissolved oxygen through their gills.

Salmon are coldwater fish. They need clean, clear, cold water to survive. They prefer temperatures ranging from 42 -70º F.

Pose the question, “Do you think our local water body has what salmon need to survive during any stage of their life?” Ask students to write this focus question and their predictions in their science notebooks.

Ask students, “How can we find out if our local water body has what salmon need to survive during any stage of their life?”

Exploration

30 minutes plus 2-3 hours for field trip

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Tell students that they will be investigating a local body of water to decide if it can support salmon.

Review the Salmon Needs chart created in the previous activity. Explain to students that they will use the chart to record their findings. They can circle the items that they can see are present, and cross off ones that are not. In the case of predators, allow them to circle the animals they know live in the area. They need not be actually seen during the field experience to know they are a danger to the salmon.The last column is for them to record any additional observations or notes about the water or the area surrounding it.

Additionally, you may want to distribute the Water Investigation Worksheet and have students answer these questions:

Nursery areas for egg, alevin and fry:

• Are there places under the banks where young salmon could hide?
• Is the water cold and moving?
• Can you see any insects on the bottom of the stream, in the stream, or flying in the air?

Spawning areas:

• Is the the water clear? Can you see the bottom?
• Is there gravel (rocks the size of a pea) on the bottom of the stream?
• Is the water deep enough over the gravel that an adult salmon could swim there?
• Is the water cold and moving?
• Would the salmon be able to come up the stream to this place without running out of water, reaching a waterfall they can’t jump over, or encountering lots of garbage?

If there are several parent volunteers, divide students into working groups for the field trip, and have them investigate different areas of the water body. Or, if there is enough time, the entire class can visit several areas of a water body, or perhaps more than one location. For example, streams can vary from one spot to another, and students may find evidence of salmon habitat in one place and not in another. Also, before going on the field trip, remember to review field trip etiquette with the students.

Upon arrival at the field site, give students several minutes to explore their surroundings and notice everything that they can about the site. Have a brief discussion about this particular body of water and how it fits into the bigger local watershed.

Circulate among groups as they work on their investigation and assist each group in taking the temperature of the water. A small mesh net can be used to dip into the water to check for evidence of aquatic insects as food for young salmon. Take several digital photos to document student observations.

Explanation

40 minutes

Upon return to the classroom, have students meet in small groups, paste their data sheets into their science notebooks (if necessary) and share their notes from the fieldtrip.

Ask the groups to decide if their evidence leads them to the conclusion that salmon habitat DOES or DOES NOT exist in the study area, and if so, for what life cycle stage of salmon.

Give a specific format for a science notebook entry that guides students to make an evidence-based statement, such as:
Based upon (evidence type 1), ____________ (evidence type 2), and (evidence type 3), we conclude that . . .”

These statements might be accompanied by a section, “We recommend additional study to answer the following questions . . .”

Ask students to reflect and comment on the importance of the study area to salmon and to the watershed as a whole.

Elaboration

30 minutes

Have each group post their findings and digital photos on the “Rivers to the Sea and Back Again” forum on the Alaska Seas and Watersheds website, and look at postings that have been submitted by other students around the state. They can post questions about other students’ findings.

Alternatively, share findings with a partner school by email.

Evaluation

Check science notebooks to assess the students’ participation and understanding.

Extension

Add a chart titled, “How does a fish compare to a human?” Students can complete the chart, showing how fish compare to humans regarding their different systems, i.e., respiratory, digestive, reproductive, nervous, circulatory, etc.

Find out about obtaining a permit to incubate salmon fry in your school and release them into a nearby stream through the Alaska Department of Fish and Game’s Salmon in the Classroom. Also available through the UAF Cooperative Extension/4H Program: Salmon in the Classroom Program for Rural Alaska.

Learn both names for the five types of Pacific salmon.

Dissect a salmon.

Curricular Connections

Writing.

Students may extend their understanding of the investigation through a writing activity (salmon storyboard) that tells the story of a salmon’s life journey from the salmon’s point of view. Evidence of the proper life stages taking place in the proper parts of the watershed should be apparent. The story can be used later to accompany the watershed model activity in Investigation 5.