Experience 2: Discovering Rivers

Topic: Youth will be introduced to macroinvertebrates found in the rivers of Maine.

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. Recognize the different perspectives about the river.
  2. Explain how to collect invertebrate samples and why scientists collect these.
  3. Talk about some of the restoration work being done to Maine rivers.

Background Information for Facilitator:

During this experience, youth will learn about how aquatic biologists can test river health by looking at the macroinvertebrate samples. Macroinvertebrates are small organisms without backbones and are commonly found in many types of wetlands. Some examples of invertebrates are dragonfly nymphs, mayflies, caddisflies, and snails. Invertebrates respond with a range of sensitivity to many different kinds of pollution and are used for toxicity testing to develop water quality standards. By learning about how invertebrates interact with the water, youth will learn a new perspective on how we can determine water health.

Facilitator Note: The youth may have questions about keeping the riverways clean and the facilitator should be prepared to talk about this.

This activity is designed to be done both indoors and outdoors. The facilitator should test the location and make sure there are invertebrates to collect. Depending on the location or time of year, getting to the river can be a challenge. If you are unable to make it to a river near your location this activity can also be done indoors. If you are bringing students to the water, it is important to remember that it can be dangerous by the river and to be safe when approaching the river during certain times of the year. It is advised to find a spot before doing the experience making sure that the path is easily accessible for all participants. Please refer to your organization’s safety protocol for specific information.

Materials

  • Outside Activity:
    • 5-Gallon Bucket with rope attached
    • 5 Aluminum trays
    • 26 Invertebrate identification sheets
    • 20 Tweezers
    • 1 Box of gloves
    • 10 Microscopes
    • 15 Plastic cups
    • 15 Plastic spoons
  • Inside Activity:
    • 5 One-Gallon Buckets
    • 5 River Sample 1 bags

      clear bag of flash cards of species found in Maine rivers
      River sample cards (Photo Credit: Tyler Tibbetts)
    • 5 River Sample 2 bags
    • 5 River Sample 3 bags
    • 26 Invertebrate identification sheet
    • 10 Magnetic fishing poles
    • YouTube videos (facilitator will need a way to show these to the group)

Vocabulary

  • Perspectives – One’s view or attitude toward something; a point of view
  • Invertebrates – An animal lacking a backbone
  • Benthic – Living on the bottom of a body of water
  • Macro – Visible with the human eye
  • Micro – Too small to see with the human eye

Methods

Part 1: Introduction

  • Ask youth the following questions:
    • What do you think of when you think about a river?
    • Who here has visited a river? When? Where?
    • What do you remember about your experience?
    • Are there any rivers that are meaningful to you/ your family/ your community?
    • Why are rivers important? (if the activity is planned to be outside, have the students answer some of these questions while by the river.)
  • Facilitator Note: you could do an ice breaker where students are asked to look around in nature and then reflect on how it makes them feel or have them tell stories about what the environment is telling them.

Part 2: Investigating Invertebrates (Outdoor Option)

  • Have the youth be prepared to go outside for this activity. Depending on the weather, this could involve needing proper dress wear like snow or rain jackets. Remind youth that they would want proper footwear before doing this activity. Also, this would be a good place to let the youth know the safety expectations for being outside for the activity. After talking about expectations, remind youth that they will need to be safe when traveling to and being around the river.
  • Next, explain what an aquatic biologist does for a job and introduce a video that shows what the youth will be doing today. An aquatic biologist is a professional who studies organisms that live in water. Here is a video that can be shared with the youth: Benthic Basics – Sampling With a Kick Net (YouTube).
  • Break the youth up into groups of 3-5 and have the groups decide who wants to help carry the buckets.
  • As the group is traveling to the river, have them stop midway to reflect on their surroundings. “How does this make you feel?” and “What do you notice?” Have the youth share in their groups the responses to these questions. Remind students that this is another example of perspectives.
  • Once you are out at the water (reminder to look at the background for safety information) explain to the youth what they will be doing today.
  • Start by asking the youth if they know what a benthic macroinvertebrate is. Give them a moment to explain their ideas.
  • Optional Questions:
    • Have you ever seen bugs in the river/ stream?
    • What did they look like?
  •  If they have a hard time coming up with ideas, ask them if they know what a vertebrae is. If they say no then have all the youth reach out their hand and then feel the back of their neck and explain that these are vertebrae. Next, explain that invertebrates don’t have a spine. Benthic means anything living on the bottom of a water source and macro means anything that we can see with our eyes. For example, if it was micro that would mean that we could not see it with our eyes.
  • Before doing the demonstration this is a good point to talk with the youth about the importance of respectfully treating the organism that we will be looking at today.
  • Demonstrate to the youth how to collect a sample. Throw the bucket on the string into the river and slowly pull it back making sure that sediment is collected.
  • Use the plastic cups to put some of the samples into a tray and show the students how to find invertebrates. Use spoons to move the invertebrates from the tray to the paint trays so it’s easier for the youth to see the different invertebrates. In the video shown earlier, this process is demonstrated. Start at 5:00 for a review of what this would look like for youth.
  • Now that the youth are ready, have the groups go one-by-one to collect samples.
  • Once the youth have collected their samples, have them identify them using the identification sheet. For example, if a youth collects a dragonfly larva they would pull out the identification sheet and try to see which picture it looks the most like. If the youth are having a hard time identifying their samples, the facilitator could be available to show some examples.
  • After collecting samples, have the youth brainstorm reasons why we would want to collect these samples.
    • What role might invertebrates play in the health of the rivers?
    • Do fish eat them?
    • What other things in the water might be related to invertebrates?
  •  After some time discussing, explain to the youth that the invertebrates can be used to help identify how “healthy” the water is. If there is a high diversity of invertebrates it usually means that the water is healthier.

Part 2: Investigating Invertebrates (Indoor Option)

  • Start by asking the youth if they know what a benthic macroinvertebrate is. Give them a moment to explain their ideas.
  • Optional Questions:
    • Have you ever seen bugs in the river/ stream?
    • What did they look like?
  •  If they have a hard time coming up with ideas, ask them if they know what a vertebrae is. If they say no then have all the youth reach out their hand and then feel the back of their neck and explain that these are vertebrae. Next, explain that invertebrates don’t have a spine. Benthic means anything living on the bottom of a water source and macro means anything that we can see with our eyes. For example, if it was micro that would mean that we could not see it with our eyes.
  • Next, explain what an aquatic biologist does for a job and introduce a video that shows what the youth will be doing today. Here is a video that can be shared with the youth: Benthic Basics – Sampling With a Kick Net (YouTube).
  • Break the youth up into groups of 3-5 and then explain to them what they will be doing today. Each group will have a bucket that they will be sampling from using a magnetic fishing pole.
  • Show the youth an example of a sample that they are going to take. Pull out the magnetic wand (fishing pole), reach it into the bucket, and collect a sample. Explain to youth how what they are doing is only a model of what real scientists do.
  • Next, have all the students start with River Sample 1. Each group will have one bucket. Each bucket should be filled with the invertebrates labeled River Sample 1. There should be 5 bags with this label so each bucket has the same sample inside. Youth in each group should take turns collecting a sample. As they collect each sample they should share with the group what they collected and each member of the group should record that species on the identification sheet for River 1. They should continue doing this until they have collected all the invertebrates from the river sample.
  • Next, once the youth have determined all the invertebrates in the sample they have to work together to figure out the quality of the water that they just sampled. They should determine that from River Test 1 that the water is pretty clean because there was a diverse amount of invertebrates.
  • Youth should do the same process for River Samples 2 and 3. River Sample 2 should have a moderately diverse population of invertebrates which means the sampled water is not so great. After they collect River Sample 3 it is important to recognize that this sample is the least diverse which indicates this water sample is the worst of the three. If youth have a hard time determining the health of the samples, remind them that some invertebrates are sensitive to pollutants. When those invertebrates that are sensitive to pollutants aren’t present, this means that the water in that area has some pollutants present which means the water quality is worse.

Part 3: Reflection

  • After doing the activities there should be a time for the youth to ask any additional questions that they might have.
    • What did you notice?
    • What do you wonder?
    • What do you want to know more about?
  • Now that students have had a chance to talk about water quality, refer to some of the work that the Penobscot Nation is doing to help restore the rivers in Maine. This can be noted from the video above. Discuss as a group:
    • Does anyone know of other ways to test water quality?
    • How could we test to see if the water is healthy?