Experience 5: What’s in the Water?

Topic: Youth will be introduced to eDNA and how it can be used to identify species.

Time: This lesson should take approximately 45-60 minutes to complete.

Learning Outcomes

At the end of this activity, youth should be able to:

1. Explain at a basic level how eDNA works.
2. Talk about how eDNA can be used to help fulfill our duties to be in good relations.

Background Information for Facilitator

Environmental DNA (eDNA) is collected by scientists to discover what species are currently living in a specific area. The samples used to gather eDNA evidence can be taken from the water, air, or soil. One key takeaway for youth about eDNA is that it is used to tell what is present in an environment. During this experience, youth will be tasked with looking at a picture of an environment and trying to determine what is going on. They will determine what they see compared to “eDNA results” that will be introduced in the second part of the experience. Through storytelling, they will explain what they notice about the environment. If youth struggle with storytelling, the facilitator could remind them about previous experiences to help them construct stories about what might be happening in the scene. For example, in the scene, there are bear tracks and the facilitator may ask the youth what they think the tracks might tell us. During the second part of the experience, the youth will be looking at “data” that resembles what an eDNA sample might look like. The idea behind the sample is that if a species has a green light for one of the samples that means that species was present in the environment that youth looked at. If there was a red light that means that the species was absent from the environment and if there was a yellow light that means that the data was inconclusive or uncertain. Using these sample sheets the youth will be asked to continue the story of the environment using a different perspective. One thing to note for this portion of the activity is that beavers will be present in the data collection but were not shown in the pictured scene.

While youth are telling their stories about the environment, remind them about perspectives and how we can all be seeing the same pictures but we may have different stories to tell about what’s going on. This will reinforce different points of view using the same information.

Materials

• river scene pictures
• eDNA sample sheets
• Big Tracks, Little Tracks by Millicent E. Selsam
• sheets of blank paper
• pencils
• projector or way to display a short video

Vocabulary

• eDNA – Environmental DNA, genetic material left behind by species (hair, fluid, skin)
• Ecosystem – An environment where the land and species are interacting with each other

Methods

Part 1

• Begin by asking youth what stands out to them about the past few experiences the group has shared. This could be done in small groups or as a whole group, where everyone shares something they found interesting or that leaves them with new questions. Facilitators may want to remind the youth of some of the material discussed in the last few weeks (maps, invertebrates/ water sampling, parts of a fish, food chains, and food webs).
• Introduce a book called Big Tracks and Little Tracks, a story about following animal prints by Millicent E. Selsam
• Ask the youth:
  • What do they think a nature detective would do before reading the book?
  • What does the title imply?
  • Why do they think tracks might be important to pay attention to?
• Read the book out loud. As you lead the youth through the book ask questions like: What is something that tracks could tell us? or What are some other ways that could tell us if a species was present in an environment?
• After finishing the book, have the youth make a prediction about how big they think a black bear track is. After they have made their predictions, let them explore some pictures of tracks in comparison to humans so they can see how big some tracks are.
• As a group, discuss:
  • What surprised them about the life-size tracks?
  • Which tracks would they like to see?
  • Have they seen any of these tracks, or any tracks before?

Explore

• Explain that they are being tasked with becoming nature detectives. Together we are going to look at a picture (using a River Scene sheet provided in the tool kit) and determine what we think it is trying to show us. Everyone may not have the same ideas about what the picture is depicting, and that is ok. Let the youth know that they will be tasked with telling stories about the river scene after they have had time to examine it.
• Split the youth up into groups of 3 to 5.
• Give the youth about 5 to 10 minutes to examine the scene. Youth should notice that there are a number of species that were discussed in previous lessons. Youth are encouraged to tell stories based on material they learned in previous activities. Provide paper if the youth would like to take notes and ask them to prepare to tell stories based on what they can see from the scene.
• After they have had time to make sense of the River Scene and talk with their group about the story, or at least part of the story they see, have everyone gather in a circle. This will be the time to share the stories that have emerged. Encourage each youth to tell a story about one of the species that they see. As they tell their story, allow the youth a chance to build on other stories with other observations that they might have made about the species. Go around the room and allow each youth/ group a chance to tell their story about what they are seeing. Feel free to add priming questions that are related to topics already discussed in prior experiences.
  • Are invertebrates present?
  • Are there fish present?
  • What about an eagle?
  • Do we notice any species that we haven’t talked about before?

Part 2: eDNA Sample

• After the students have had a chance to tell their story about the environment, introduce a new perspective by introducing what Environmental DNA (eDNA) is. Scientists collect samples from rivers and on land to find this type of DNA in order to discover what species are currently living there.
• This is a 2-minute video that gives a good quick explanation for the youth to know what eDNa is. Show this video explaining what eDNA is: What is environmental DNA (eDNA)? (YouTube).
• Hand out the eDNA sample sheet to the youth to interpret what the data means. Explain that there are a few key things to help understand this new type of story:
  • On the left, the species name is listed.
  • Next to each species’ name are three samples. One was collected in the spring, one collected in the summer, and then finally, one was collected in the winter.
  • Notice that there are traffic lights.
    • The green traffic light indicates that an eDNA sample was found for that species which means they are present in the environment that we observed during that time.
    • The yellow light indicates that the species might be present.
    • The red light indicates that no eDNA was found which would mean that the species was not present in the environment.
  •  There is a key on the back to help decipher the data.
• Facilitator demonstration: Start by modeling to the youth how to interpret the eDNA data about the salmon.

You might say something like: “For the salmon, I see the spring sample shows a green light. The key below will tell me what this means. It says, ‘the green light means the species was present in the environment.’ So I know there must have been salmon in the area during the spring. The samples taken during the summer and winter also show a green light. This means the salmon must have been around in those seasons as well.”

• Whole group interpretation:
  • Next, work together as a whole group to interpret the data for the Algae.

• • Help them work together to go one season at a time, determining what the color of the traffic light is and what that means in terms of absence or presence.
• Independent work:
  • After completing the group interpretation, give students time to work independently to interpret the remaining data. Once they have had enough time to look at the data, ask them to connect the story they are constructing from the data with the story they have constructed from the River Scene. If the youth have a hard time doing this ask questions like:
    • Why might the bear not be present in the winter?
    • Does anyone notice that a beaver is present in the environment?
    • Why don’t we see it from our observation?
    • Help the youth draw connections between the data and the environment.
  •  After all the stories have been told about the environment, ask the youth if they have other questions related to the topics discussed in the experience. You could ask questions like:
    • What did others notice that you might not have noticed?
    • How did you conclude some of your observations?
    • How might you use this new view on perspectives the next time you have an opportunity to explore the woods or watershed?

---

Supplements to Experience #5:

• eDNA Sample
• River Scene