Oh Deer: Invasive species style

In this active and competitive game, students experience how a community of native animals and plants changes over time in response to resource availability in their habitat. Students collect data during the game and then graph and analyze how predators, limited resources, habitat health, and INVASIVE SPECIES can disrupt the natural ebbs and flows of native communities. Students visualize and analyze their results using graphs and story telling.

Project Information
Grade Level: 
Middle school (grades 6-8)
High school (grades 9-12)
Professional development
Resources I used: 
Project WILD, www.projectwild.org
How should others reference your work?: 
Oh Deer: Invasive Species Style, original lesson plan by Project WILD, modifications by Sarah Morrisseau, Vital Signs, Gulf of Maine Research Institute, 2010


Working toward these performance expectations:
MS-LS2-1 - Analyze and interpret data to provide evidence for the effects of resource availability on organisms and populations of organisms in an ecosystem.

Using these science practices:
-Developing and Using Models
-Analyzing and Interpreting Data
-Engaging in Argument from Evidence

Using these disciplinary core ideas:
LS2.A: Interdependent Relationships in Ecosystems
-Organisms, and populations of organisms, are dependent on their environmental interactions both with other living things and with nonliving factors. (MS-LS2-1)
-In any ecosystem, organisms and populations with similar requirements for food, water, oxygen, or other resources may compete with each other for limited resources, access to which consequently constrains their growth and reproduction. (MS-LS2-1)
-Growth of organisms and population increases are limited by access to resources. (MS-LS2-1)

LS2.C: Ecosystem Dynamics, Functioning, and Resilience
-Ecosystems are dynamic in nature; their characteristics can vary over time. Disruptions to any physical or biological component of an ecosystem can lead to shifts in all its populations. (MS-LS2-4)

Using these cross cutting concepts:
Cause and Effect
-Cause and effect relationships may be used to predict phenomena in natural or designed systems. (MS-LS2-1)

Stability and Change
-Small changes in one part of a system might cause large changes in another part. (MS-LS2-4)

I changed things up a bit when playing Oh Deer! with my students. Due to the rainy weather all but one class had to play the game indoors. I was also worried about how well they would transfer their knowledge from a game using animals as the central focus to a research project about invasive plants.

So.... I changed the name to "The Resources Game". Students were native sweet ferns or resources (we talked about the need for sunlight, air and water). When we charted our data we kept track of sweet fern numbers and the number of resources available. We talked about plants growing slowly and how they had to walk heel to toe to model that. I warned that any sweet ferns moving too quickly would be thought of as mutants and destroyed! They chuckled at that but most did a good job keeping it safe. After several rounds we introduced a few deer as a Grazers population and began charting their numbers as well. We did 12 rounds this way and started to see some nice subtle shifts.

For the second part we began as in the first. By round four we introduced some invasives (Japanese Knotweed). I had the invasives wear neon safety googles, which they loved. If the invasive got a resource, the resource also became an invasive in the next round. The goggles were quick and easy for the kids to put on themselves as roles changed.

The next day we looked at the charts and realized what a huge mess it would be if we graphed every piece of data. I had small groups come up with a question that could be answered using the data. Once we discussed all of the different kinds of questions, small groups worked together to pick out the data essential to their question and represent it in some way. All chose to graph, but I am already seeing some interesting takes on this.

Overall I think it is going pretty well, especially considering that we were stuck indoors.

I am going to add to the previous comments- and try not to repeat the many excellent points.

This worked very well for me. When I first tried it, I had a huge problem getting the students to stop chasing each other. This year (and I am only a second yr teacher) I explicitly forbid chasing- and it worked a LOT better. We also have a child in leg braces who would not be able to participate if this was not controlled. We did seven years with just the deer- enough to see the population go up and down in response to habitat limiting factors. I did not use anything aside from hand signals to signal which habitat was which. The less bits and pieces the better. The wolf was able to tag (NOT throw a ball at) a deer. We are doing wolfquest/ learning about ecosystems with wolves so we chose a wolf for the predator. The wolf population was allowed to grow - and the deer did too - at first- then, in this closed system, the wolf population went up and then crashed right after the deers.

The invasives are allowed to go out first- and the predators can't touch them. This part of the game only lasted about 5 years. That was enough! I used green and yellow crepe paper for the natives and the invasives. We have 75 min classes- in two of my classes we had time to start graphing. I have one class of 25 that I struggle to get going- and we did most of our graphing the next time. It was a great way to get the students graphing. I did the graphs on paper- and that was good to establish good practice but the next graph will certainly be done using the computer.

When the weather was bad, we moved the tables and simply did it inside. It was fine- just had to dig some habitat out of the corners where they were 'hiding' and definitely have no ball throwing.

I use this to reference lotka-volterra predator prey dynamics- the prey population really does, in the end, control the predator and not the other way around. If I do a powerpoint, I often show the classic lynx-hare graph. Some of my students are offspring of college professors of ecology. I also have to keep myself engaged. ( I often throw stuff out that is hard, weird, or of personal interest- often it lands on receptive ears, sometimes not, but I have to keep it interesting!)

The kids had fun and I kept the numbers on a whiteboard on the side- previously I've had a student do this which also works well. I had a couple of students who did not want to participate- and I did not insist. I also transcribed the raw data for students who were missing that day. I plan to do another round sometime soon to reinforce and include the absent kids.

I completed the bulk of this activity during my class periods today (September 14th) and what a perfect day it was for this activity! I couldn't have asked for better weather. I am teaching only math this year, so had to justify doing "science" during a math class to my administrators. I ended up lining this activity up with math standards on data collection and graphing in order to make it appropriate for my setting.

I am fortunate in that I have 80 minute classes, so was able to do quite a bit in one class period. I assigned them some vocabulary terms to both define and give examples for, for homework last night. My students studied ecology in 6th grade, so considered this a review. The words were native species, non-native species, invasive species, predator, habitat and limiting factor. At the beginning of class, we did a think-pair-share activity on the meanings of these words and it was great to see them struggle with the term native. They really did bring in a lot of good descriptors though, such as adaptations, evolved, indigineous, etc.

I had three different classes do this activity, and so far have kept the data for each of the classes separate. After students have had a chance to analyze the data for their own class, then I will share the data from the other classes and have them discuss variables and conditions that might have led to differences between the classes.

For each class, I started with just the habitat folks and the native species. I did only two years that way and then introduced a non-native species. In the first class, I tried the situation where students who were non-native made different signals, but for some reason, there was confusion and they managed to get what they needed. I decided to tweak that in my next two classes and secretively gave the non-natives just one signal ( hands waving wildly above head). I decided to use that one as representing the idea of panic because they were hungry, thirsty, tired, cold and ill, yet, could find no relief. That seemed to make the whole idea of non-natives a lot more clear to everyone.

I then introduced the invasives and in all classes noted immediately how the invasives really took over. This led to a discussion about whether this model is truly accurate. We never actually answered that question, as I decided to have them reflect on that tonight and as part of a journal entry, will have them talk about the accuracy of this model and then the difficulties in interpreting graphs, charts and models in general.

I began the predator by introducing just one and in my situation the predator had to touch the prey with the ball, not throw the ball at them. That led to some immediate deaths and I had those who died sit out rather than going back in as part of the habitat. I then added a predator and rather quickly, the native species died out and was placed on an endangered species list.

When we came back into the room, we had a class discussion about the massive changed in certain years and why those changes occured. Then, I assigned the following questions:

1. How is the simulation "Oh Deer" similar to what actually happens in nature and how is it different?

2. What were the variables in this simulation? What are other variables found in nature that affect the growth or decline of a population.

3. Graph your data in any way you would like. Make sure your graph represents the data we got in class.

I gave them the choice to work with a partner or alone on these three questions and then observed their progress. I was very impressed to see several students use Keynote on the laptops to record the data and graph it with a line graph or a bar graph. It was really awesome to see.

Tomorrow, I will be going over the differences between bar graphs, line graphs, pictographs (and other graph they might choose to create) and then we will spend more time analyzing the data via our various graphs. I will also have them look at the data from other classes and see if they can determine why no two classes have exactly the same data. This will lead into a discussion of science in general, strenghs and limitations of data collection.

Issues: As others mentioned, I had some cheating going on where habitat folks changed their particular piece of the habitat to something else so they could go with their friends. This led to a discussion of integrity in science and why scientific methods are so important (oops - delved into science when I was supposed to stick with math). I also had it get a little confusing with a lot of running around, so ended up using an idea stated by another teacher and that is the native and invasive species had to run/ walk to the habitat pieces. Habitat pieces were not allowed to move. That helped a lot...so thank you Linda McD.

I have one small class (16 students), but my other two are larger (23 and 26). Normally, I prefer small classes, but in this case, my class fo 23 worked out a lot better! I actually had students ask me at the end of the day if we could do this with the whole team (65 students)! I said I would consider it, but really we have some "real" science to do by looking for real invasive and native species. They really are quite excited about doing some "real" science work and publishing it. : )

I cannot add much more to what Kathy and Ginny have already written, but will say that we are covering many of the key concepts on graphing which I normally do using Variables and Patterns. Students are telling the story, making a table, and creating a graph. We look at all three and discuss that advantages and disadvantage of each . For me, the non-science member of the team, it was great to play the game with either Ginny's or Kathy's classes. It helped to have two of us managing the group: one to count and record and the other to "run" the game. The best advice I've learned about the game ( posted earlier) is to remind the "habitat" group that they do not move! Also, I think if I were running the game myself I would have the students count off their numbers at the end of each round. As for the data not coming out right, that's okay too since dealing with real data can be messy.

It was pretty darn hot when we took the students outside to play "Oh Deer". The kids really enjoyed going outside though and playing this game. As Ginny said, we had to combine a few of our classes since some had too few to really play the game. Once we got them going they got the hang of things pretty quickly. We did have a few snags. . as Ginny mentioned. Students who dropped their symbols and or changed them as they went from one side to the other. Some of the data that we collected just didn't add up. . we asked the students what was happening to cause the error . . . they were good about 'fessing up. Make sure they just gently "tag" the habitat person rather than plow them over!

The first game with just native species the numbers changed very little. . which led to a conversation about ecosystems being in balance. After 6 or 7 years we told the habitat people that it had been a very dry year so they could not use the symbols for water or food. Once they played this round they really noticed the decline of the native species.

We introduced one predator and allowed it to reproduce by tagging one native species. After a few rounds with this rule they saw that the predators were quick to take over the natives. When we asked students how else we could play this part of the game they suggested that the predator should stay at one but the native species became habitat once they were tagged.

This next day we played the game with both a predator and an invasive species.
The predator rule stayed as before,however the invasive species had a head start and were allowed to take two habitat people who then become invasive species. The data showed them how quickly an invasive species can change the balance of the ecosystem.

Graphing is taking a bit of time for many of my students . . we are still working on this piece of Oh Deer! If it takes too long I will be saying "Oh Dear!"

Yes, I changed the name. Since we live in Northern Maine, the deer would have been a great species to use, but I kept thinking that muskies would be interesting to the students, since a new muskie fishing tournament has been gaining popularity, in our area, in recent years. I like the name "Oh Dear!", because we play until the native species crashes. The natives were the brook trout, the predator was an eagle, the non-natives were goldfish, and the invasives were muskies.

My grade 8 students had a big unit on ecosystems last year. I liked the idea of starting the year with this activity to help spiral back to the things they learned last year. So I did not review habitat much. I stressed from the start that this is a type of model. I've been going on about models a lot lately so they are used to this. They quickly decided to have food, space, water and shelter as their 4 basic habitat needs---for the purpose of the model and agreed those were pretty realistic.
I had to do it with each class separately.

One class is small---only 11 students. It's hard to play with that number, but we got the good fluctuating population in response to limiting factors by playing it with just habitat and natives for 8 rounds. I involved students, asking what was working with the model and what wasn’t, and why. Our trout population crashed very quickly when muskies arrived!

With larger classes I also spent about 8 rounds on getting them to tell me the population had to go up and down in response to resources; before I introduced a predator. I made charts ahead of time to tape on the building and record data. I didn't count habitat, just year and natives, non-natives, predators, and invasives. I stopped the game often to circle up and ask students why population was going up and down. When I introduced a predator, I had the caught prey become predators and they quickly saw that now the native population couldn't get as high as before. We tried it with caught prey becoming habitat and talked about different reproductive rates of predators, and prey. With the non-native, I kept repeating that this species needs different habitat, and they quickly got that this meant certain death. With the invasives, they really got the message why an invasive, which grows faster and uses more resources, will quickly use up the habitat, and leave nothing for the native species.

I soon ruled that habitat cannot move until native gets to it, then they have to walk together back to native starting area. No running. I made it a rule that predator could get tricky and try to get more than one prey per round but the prey would become habitat. Otherwise, if predators were allowed to reproduce, soon the predators would just deplete the natives, even though, in our version, only one predator could hunt at a time. We weren't replenishing habitat with dying predators. The kids were good at identifying how different rules produced different outcomes, and why certain rules wouldn't work with our model.

Kids were uncomfortable about choosing habitat because they got hung up a bit about "wow, you and I will reproduce?" which is pretty sketchy stuff to them. Other kids (maybe worried that staying habitat meant they weren't popular?) cheated by following a native even if he/she hadn't been chosen. This uneasiness prompted a little sermon on my part. I asked if real scientists can 'cheat' and maybe change their data a little so the result will come out the way they want. This prompted a lively discussion. Kids strongly feel this is very wrong. I reminded them that once the scientific community knows you have cheated, it creates a reputation which is very hard to change. A cheating scientist would have trouble getting funding. I reminded them we were trying to do a population study by running a model, and we only wanted to learn the truth. Did they want to do a messy, meaningless study or a reliable study? This seemed to calm people down and they could focus on 'running the population study'.

I played "Oh Dear!" and it took up an entire 80 minute block to explain the rules, go out and setup, run all four simulations (compete for habitat with no other pressure, predator, non-native, invasive), come back in, display chart, distribute handouts, and graph natives vs. year. I prepared handouts for them to graph on, and I guided the graphing, so everyone put time on x-axis, frequency on y-axis, we all made line graphs so we could use slope to compare rate of change. These were things we worked on last year.

The next class began with opener. They had to take out graphs and answer direct, easy questions such as 'what year did the population increase the most and why', etc. They did this silently and I cruised the room reading over their shoulders, holding whispered conferences as needed. Then we shared responses, discussed them. Next time, once I am satisfied that everyone sees the relationships between resources, invasive species and diversity; I should ask them to do a 'quickwrite'. They have six minutes and half a page to respond to an open ended "big idea" question about resources, diversity and invasive species. This should result in nice evidence of learning to use for a grade.

We found that Oh deer took about two 42 minute classes for just the game. Another two days for graphing. We had taken each class out to the woods behind the school the day before to talk about habitat (space, food, water and shelter), and reviewed those terms at the start of class. We set up an easel and chart paper to keep track of the data. We tracked both habitat and deer, as we wanted to be able to introduce the concepts limiting factors and carrying capacity.

We followed the rules for round 1, and found that after about year 3 or 4 an equilibrium was reached. This allowed us to talk about "steady state" versus stays the same.. and the natural variation within an ecosystem.

We started the predator prey using one predator, who could transform deer and habitat to predators. The predators quickly overwhelmed the prey. This gave us a chance to talk about the game as a model, and ask what was wrong with the model, and have students give suggestions for changes to the rules. We switched to the predator gets one deer per year, and the other tags become habitat. Even then, the predator overwhelmed the population, and the next year... the ecosystem crashed (predators and prey died.)

The Non native species round went as expected. We gave the non native a new signal, then told the habitat (quietly to the side) not to change their signs. So non natives did not live. The students seemed to get this rapidly.

Then we introduced the invasives. Each invasive got to collect two pieces of habitat, and could not get tagged by the predator. We asked students why should invasives get two habitats, and they correctly connected the faster reproduction rates to the increase use of habitat. It did not take 7 years for this ecosystem to collapse either.

Issues: Students kept forgetting to leave their "signs" up, or switched them when they saw that no habitat was available. Be clear about the boundaries, and no running. Also the predator can get over enthusiastic, so we said tag only. We ended up using the flagging tape just for the invasives. Stop at the end of each round and review with the students what happened.

#s. We ended up combining classes to get the # to play the game. Some students got to play two periods in one day. You really need more than 20 to get good data.

Data analysis: Students were assigned a round to graph, given graph paper, and then shared their graphs. Major issues? Bar instead of line graphs. Un even scales on the axises. The years were not put on lines, but instead sort of placed somewhere along the x axis. Points were connected (discrete data?) We anticipated all of this. Some switched axises (so y was years, x was deer) . We shared these graphs as a class, and reviewed some basic graphing concepts... But it will be a few more graphs before all the issues disappear.

Graphing the deer and habitat together is a really great idea. That really brings up the carry capacity and limiting factors. Do this with the predator/prey and the invasives. This also starts the idea of a "system" rather than just the animals. We are working on a quiz using the data. We hope to include the ecosystem health activity into the quiz as well. When we get that worked up, I will figure out how to post it.