In today's Daily Do, Why do we seem to only catch carp? students engage in science and engineering practices and use cause and effect as a thinking tool to make sense of the phenomenon of only catching Asian carp while fishing (when once it was more common to catch other fish). Students explore how the introduction of a new species to an ecosystem can affect the existing interactions and dynamics of that ecosystem. They also learn this invasive species was initially brought to the United States by humans to solve a problem, but is now endangering the Mississippi River Basin and is threatening the health of the Great Lakes.

Begin by telling the students you (or someone you know) have encountered a puzzling situation and you want to share with them. You have noticed the kind of fish you catch while fishing has changed. For years you caught bluegill, bigmouth buffalo, and bass (or another local fish) but recently all you catch are species of Asian carp. This last time you went fishing, you noticed a sign (above) that specifically mentions the Asian carp. Ask students to read the warning sign and ask what they infer about the Asian carp based on the sign's message.

Guidance: Students may think the fish is endangered and the area is being used to help get the population back up. Others may think this fish is bad for the water and the sign makes sure people don't accidentally spread them around. At this time, allow all ideas to be shared without judgement as they will figure out more about the sign later. You can also use this activity as a formative assessment to note students ability to infer meaning from texts and graphics since this sign does not give any reason why individuals should obey the warning.

After student share some of their inferences, have them individually brainstorm ideas about what might be going on at the lake where you have been fishing. Next, have students share and compare their ideas with a shoulder partner. Tell students they can add any ideas their partner shared to their own lists if they like or agree with the ideas. Point out that in science, the process of sharing ideas is a really important part of figuring out why or how something is happening.

When students are done sharing, tell them you wanted more information on the Asian carp and found a short video clip to share with them. Have students create a notice and wonder t-chart in their science notebook. Tell students you will play the video twice, so they can watch the video without recording their observations the first time. Show the video, Carpe Diem: Is This the Answer to Our Fishy Problem (below) from the beginning until 1:02 (stop just as the title sequence starts). Play the video clip again, and this time ask students to record their noticings and wonderings in their t-chart. Have them share what they noticed about the fish with a shoulder partner and then with the whole class. Record students' observations in a shared space. Typical student notices include there are a lot of fish and the fish seem to fly out of the water.

Next, have students share their wonderings with their shoulder partner (this can be a new partner or the same one). Tell students to each pick one question about the Asian carp or something related to the Asian carp they would most like to answer. Have students record their question in a new space in their science notebook. Prompt students to think about how they might answer their question by asking, "What kinds of investigations could we do and/or what additional sources of data might we need to figure out the answers to our questions?" Ask them to record their ideas below the question in their science notebook.

Have students individually share both their question and their investigation idea(s) with the whole class. Create a class record of questions and ideas. Common student questions could include:

• Are the Asian carp bad?
• Where did the fish come from? How did they get here?
• Are the Asian carp eating all the other fish?
• Why would you have to throw your bait away and wash off your boat?
• Why did they call the Asian carp the enemy?
• Are Asian carp only in the Mississippi River?
• Why would people want them to stay out of the Great Lakes?
• Do people eat Asian carp?

After all the students have shared their question and ideas for investigations, ask students what they think they should figure out first. Many students will want to know about how the fish "fly", but guide the discussion to needing to know more basic information about the Asian carp first. For example, you might say, "Let's remember our goal, what are we trying to figure out?" Lead students back to figuring out why you are only catching Asian carp when you go fishing. Students should come to the conclusion they first need to figure out how the Asian carp got to your location (or location of interest) and if they are affecting the other fish that live there.

Guidance: Ideas for investigations will vary depending on where you live and how much familiarity students have with Asian carp and fishing in general. Having students think about and suggest ideas to investigate the answers to their questions helps build problem-solving skills and allow opportunities for students to connect previously-learned science ideas to a new context. Use these activities and discussions as formative assessment opportunities to see what prior learning, life experiences and interests your students are bringing with them into the classroom. At this point, it is not necessary to correct any misconceptions or incomplete ideas about these science ideas as they will have opportunities to change their thinking over the rest of the Daily Do lesson.

To find out more about the Asian carp and how they ended up in lakes or rivers in the United States, have students read the article What are Asian Carp? posted on the USGS website.

As students read, have them document ideas they are not sure about and information that might help them in figuring out why you are only catching Asian carp when you go fishing. When they are finished reading, have students work in small groups to come up with a list of things from the article they think are important to know to explain why the phenomenon is occurring. Engaging in discussion with their peers allows opportunities for students to gain clarity around any ideas presented in the article they were not sure about. Big ideas that come out in the What are Asian Carp? article should include:

• Carp are not native to North America.
• Asian carp were first brought here by humans to solve a problem (control algal blooms).
• There are different kinds of Asian carp (bighead, black, grass, and silver)
• The carp are now in the Mississippi and other large rivers.
• Asian carp compete with native fish for food and habitat.

Guidance: The information from the USGS website could be printed and read as a class using a close read strategy.

Now that students learned a little more about Asian carp, ask them "What could we do now to figure out how Asian carp are affecting the local fish and their environment?" You want to guide students to needing to figure out how the ecosystem has changed since the introduction of the Asian carp. If students did the Why can't I see the animal? Daily Do, prompt them to think about how they figured out the role their organism played in its ecosystem by using food webs.

Using the data table below, have student first look at the Common Name and Status columns and ask them what they notice. They should notice all the carp are "introduced". Then ask them what they think the terms "native" and "introduced" mean. Confirm or tell students that native means that the species are local (long-term residents of the ecosystem) and an introduced organism (non-native) comes from somewhere outside of the ecosystem.

Next, have students focus on the native organisms and the Diet column. Students may be familiar with terms such as herbivore, carnivore and omnivore but "planktivore" or "benthivore". If students are not familiar with these words, consider having a short discussion to surface prior learning or provide context to these new terms.

• Planktivores are fish that eat plankton. Plankton belong to the kingdom Protista and include zooplankton (tiny animal-like organism) and phytoplankton (small plant-like organisms such as algae).
• Benthivore fish are commonly known as "bottom feeders" because they feed on or near the bottom of a body of water eating things such as dead organisms, algae and - if carnivores - other bottom feeders.

It is important to note at this point we are interested in the information students can pull from the chart and not memorizing definitions of terms. However, some basic information about the terms is beneficial for context.

Now, ask students what they notice about what the native fish eat. Noticings should include:

• There are many planktivores.
• The Largemouth Bass is the only predator.
• There are two omnivores.
• Some juvenile fish are planktivores but they are omnivores when they are adults.

Now ask them to look at the fish that have been introduced and notice what they eat. Noticings should include:

• All the carp eat planktivores except the common carp.
• The common carp are the only benthivorous fish.

Ask students to consider what might happen to the amount of food available to the native fish. Would all fish native to the ecosystem be affected? They should come to the conclusion that

• Asian carp are eating the same food as most of the native fish.
• Common carp don't seem to eat the same thing as any of the native fish.

Now that students figured out the Asian carp are eating the same food as many of the native fish, have students work in groups to create a food web (model) to predict the effect(s) carp would have on the ecosystem they are introduced to.Would the introduction of carp to the ecosystem pose the same threat to the different species of fish living there? Have students draw their models on a whiteboard or poster (or use a collaborative digital tool).

Optional Activity: Using food webs (models) to make predictions about ecosystem interactions can be done several ways. One option is having students work in small groups to place the fish from the data table in a food web based on where they think they go. However, students should quickly conclude they do not have enough information to create a complete food web as there is no information on what the omnivores and predators listed in the data table eat. Students could research this information or it could be given to them to develop a more comprehensive food web. Another option would be to allow students to create a food web of a local river or lake that has been invaded by Asian carp. When students finish their food webs (models), they could participate in a gallery walk noting similarities and differences between group models. After the gallery walk, have a whole-class discussion to create a class food web. Encourage students to share their models and their reasoning to explain how the Asian carp is affecting the ecosystem.

Transition the class so students can share their food web (model) with the class. After all groups share, have students decide which explanation best predicts what would happen to an ecosystem Asian carp were introduced to. Students should conclude that because the Asian carp are eating the same food as many of the native fish, more fish are competing for the same food source. If the native fish don't get enough food to eat, they will die. Students should also figure out that rivers and lakes have a limited amount of space. As the Asian carp population grows, they crowd out native fish and may still have to move into other rivers and lakes to find space to live.

Tell students that organisms introduced to and then "take over" an ecosystem are called invasive species. However, not all non-native species are considered invasive. For example, the common carp also lives in the same waterways as the Asian carp and yet, people are not trying to get rid of them. Ask students to refer back to the data table and think about why the the Asian carp (silver, black, grass, and bighead) is considered invasive but the common carp is not and then have them share their ideas with a partner. Listen for students to share the idea that common carp are not threat to the native fish populations because they are the only benthivore fish (bottom feeders) in the ecosystem.

Students have figured out several things about Asian carp, but still need to know:

• Do the Asian carp have any predators?
• Would it really matter if the Asian Carp got into the Great Lakes? (The Great Lakes are so huge!)
• Can we do anything to get rid of the Asian carp?

To help students answer some of these questions, show the short video from PBS, Midwest battles to keep invasive Asian carp out of the Great Lakes (below). As students watch the video, encourage them to jot down anything they think is important to answering the remaining questions.

Now that students have figured out why you seem to only catch Asian carp when fishing and what people have done in some river systems to keep the Asian carp from entering the Great Lakes, prompt students to think about the questions we had at the beginning of the lesson:

• Are the Asian carp bad?
• Where did the fish come from? How did they get here?
• Are the Asian carp eating all the other fish?
• Why would you have to throw your bait away and wash off your boat?
• Why did they call the Asian carp the enemy?
• Are Asian carp only in the Mississippi River?
• Why would people want them to stay out of the Great Lakes?
• Do people eat Asian carp?

Students should recognize they can answer many of these questions now based on the information they have gathered and what they have figured out. Facilitate a discussion around what they think might happen if the Asian carp eventually do get into the Great Lakes ecosystem.

Finally, have students develop a claim to answer the initial lesson question, "Why am I only catching carp when I go fishing?" Students should use evidence and scientific reasoning to support their claim. An example of a student claim may include:

People are only catching Asian carp in the lake (or river) now because they are taking over that ecosystem. According to the data table, Asian carp eat the same food as the native fish which means there is not enough food for them and they are dying. As the population of Asian carp grow, they take over the water system so that is why people are only catching mostly Asian carp in the lake now.

Now that students have figured out how the Asian Carp is changing the ecosystem, consider researching an invasive species in your area. This Daily Do can also be used as a springboard to dive into predicting other ecosystem interactions, evaluating design solutions to a local invasive species problem, or looking at non-native organisms which are not considered invasive.