Tragedy of the Commons: A Simulation

The purpose of the simulation is to demonstrate how individuals might use one or more common resources and the potential result(s) of various resource use approaches.

I usually form student groups of 4. Each “fisherperson” receives two straws which they will tape end-to-end, (after removing paper wrap). Each group of 4 students places 16 “Fish” (M&M's, Pepperidge Farm Goldfish, Raisins, … others) in the ocean (or “Lake”), which I usually have them represent with a paper plate, paper towel, or a piece of paper. Each “Fisherperson” must catch at least one fish per fishing season, or they will perish. They may catch as many fish as he/she wants. I tell the students that we will have three fishing seasons. With each lasting 20 seconds. After each fishing season, the fish “reproduce”: For every two fish remaining in the commons, one “new fish” will be added (from the stock - each group has a cup of many fish to draw from).

Some students realize exactly where we’re going with this; others simply focus on those M&M's, goldfish, etc. Having (quietly) stated to the class that we would have 3 fishing seasons, I usually go ahead and have one more, maybe two more.

This is a simple simulation to introduce Garrett Hardin’s “Tragedy of the Commons” essay (June 1968)

One cause of environmental degradation is the overuse of common-property resources, which are owned by no one but are available to all users free of charge. Most are potentially renewable. Examples include clean air, the open ocean and its fish, migratory birds, Antarctica, gases of the lower atmosphere, the ozone content of the stratosphere, and space. In 1968, biologist Garrett Hardin called the degradation of common-property resources the tragedy of the commons. It happens because each user reasons, “If I don’t use this resource, someone else will. The little bit I use or pollute is not enough to matter.” With only a few users, this logic works. However, the cumulative effect of many people trying to exploit a common-property resource eventually exhausts or ruins it. Then no one can benefit from it, and therein lies the tragedy. (Miller text)
Using Common Resources Name: ______

Names of Fishing Mates:

______

______

______

LOGISTICS:

Groups of 4

Each group starts with 16 fish (4 regular M&M's, 4 peanut M&M's, 4 raisins, and 4 cereal pieces)

Each student fishes with 2 straws taped together end-to-end. Hands cannot be used during the fishing process!!!

Each fish has a "current market value":

- Regular M&M's = $5.00- Raisins = $3.00

- Peanut M&M's = $10.00- Cereal = $3.00

Each student must catch one fish per season in order to stay in business; it is up to each student to decide how many, beyond the require one, fish will be harvested.

Each fishing season will last 20 seconds

At the end of each season, one fish (of the same species) will be added for each pair of fish remaining in the commons.

DATA: Complete the following

Fisherperson / Year 1 / Year 2 / Year 3 / Year 4
Total for Group
Total Fish Harvest
Total Income