The Tragedy of the Commons part 2: Regulated Fishing

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Big Idea

In the second day of the Tragedy of the Commons lesson, students attempt to avoid environmental and economic collapse by regulating their fishing simulation with rules and "laws" generated by each group.


This lesson is a direct follow up to part 1 of the Tragedy of the Commons lesson sequence: unregulated fishing.  

Students will again be simulating fishing in a “commons”.  Depending on the size of your class and how the simulation went the previous day, you may need to restock your own supply of candy “fish”, especially as groups are likely to have larger populations during this second go-round of the simulation.  

Additionally, you should make additional copies of the Accounting worksheet (1 per student) and the International Fishing Commission worksheet (1 per group).

The main difference between this lesson and the first lesson is that students know the rules of the game (i.e., they understand how fish populations rise and fall), and students can talk with the other students in their group to devise laws and regulations to prevent the “tragedy of the commons” and safeguard the long-term economic and environmental health of their fishery.     

Connection to Standard:

This lesson asks students to participate in a simulation to model the environmental effects of a an regulated economy.  To perform the simulation, students must follow a complex, multistep procedure.  Following each day of the simulation, students must use the data they collected and their anecdotal experiences as evidence to support claims and make predictions.  


Warm Up

5 minutes

I begin this second lesson in the sequence with the announcement of some good news… more candy!  I ask students what happened in their fisheries on the previous day and most reply that either their fisheries were totally wiped out, or they were left with nothing but undesirable fish (in this case, the black licorice).  I then ask if anyone figured out the patterns of fish population growth. Hopefully someone explains the general rule, but if not, I explain that for every two fish of a particular species remaining at the end of a round, I would add one more.

After that brief review of the previous days results and the explanation of the rules for fish population growth, I let students know that we will be repeating the simulation, but with the added step that each group will establish their own laws and regulations to ensure the long-term health of their fisheries.

I then also mention that the winning team (those with the most money at the end of four rounds) will receive the candy leftovers (anything remaining in the bags).  With this incentive for cooperation established, we move on to the student legislation segment.

Student Legislation

10 minutes

To begin this segment of the lesson, I distribute one copy of the Laws and Regulations worksheet to each group.  This worksheet is used by each group to establish fishing regulations for their region.  

This worksheet asks students to write down any laws or regulations that their group will agree to follow during the simulation.  The worksheet also asks for them to list a rationale for the law.  Additionally, the worksheet asks for time of enactment of a law in case it is added later in the game, although I don’t specifically have them focus on this fact at the outset.  


As the groups are discussing and enacting laws that they will follow, I distribute the supplies to each group and supply their fisheries.  I follow the same rules for set up on this day as the previous day, with each group beginning with 6 members of each of the 4 “fish” species.


Once I’ve set up each group and they have finished writing their initial laws and regulations, we are ready to begin the simulation.


40 minutes

The simulation follows the same procedure as the first lesson.  The main difference here is that between rounds, students are given the opportunity to spend 5 minutes in a legislative session to discuss strategy with their group and determine if they want to enact new laws of repeal any current laws.  As they are discussing new laws, I restock the fisheries.

Another difference between the first lesson and this is that I take each group’s total revenue for the round and write it on the board to heighten the drama of who’s going to win all the candy.  However, I purposefully do not share information about the populations of each fishery, adding a level of uncertainty that keeps the game interesting (e.g., “Oooh… we’re behind them in revenue, but I think if we can hold to our strategy one more round then it’s going to pay off!”).

Prior to the fourth and final round, I announce that it is the final round.  Students likely remember from the previous day that final isn’t ever final and I intend to use their remaining populations as the basis to restock their fisheries one final time for “their children’s future”.  I let students know that this will again be the case, and that they will add their total revenue for all 4 rounds plus the value of the fishery left “for their children’s future”.  

I then let them know that due to the “scientific fact” and “law of economics” that “a bird in hand is worth two in the bush”, the value of their “children’s” fisheries will be determined at only 66.6% of the market value of their fish population.  (This was the best I could do with making it equally sensible to fish all the fish or conserve all the fish, perhaps some genius out there could leave a better suggestion in the comments?  Thank you!)  

One final reminder I give them is that without catching at least one fish, they cannot pass on their fishery to their children, automatically taking their group out of the running for the sweet candy prize.

Wrap Up

5 minutes

On this second day, it’s unlikely to have any group completely deplete their fisheries, so I don’t worry about groups finishing too early.  If, for some reason, there is such a group, I would hand out the Day 2 Questions worksheet early and ask for their help in restocking fisheries between rounds.

Once all groups have tallied up the remaining value of their fisheries and I have added these to the running totals, a winning group is announced.  To all but one of their member’s dismay, I hand the prize entirely to the most successful member of the group.  No reason, just that it provides another layer of tying human interest, economics, complex behavior, cooperation, etc. into the teaching of environmental science.  Hopefully they’re ethical enough to share their spoils with their cooperating members.

After the prize has been awarded, I distribute the Day 2 Questions worksheet to each student and ask them to complete the questions for homework.  


Please Note that I collect the group work (the "International Fishing Commission Report" and "Laws and Regulations") before the students leave.  This way, if any group member is absent on the day of the following lesson, the rest of the group can still complete their work.