Building the Fish Banks Model and Renewable Resource Depletion

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3.3.3 Questions
1. Why is this a negative loop?
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2. Run the model and observe the behavior of Total Catch per Year and FISH.
Notice that the fish population drops significantly before any noticeable change
occurs in the catch. After one year, the Catch per Ship dropped by only 4% while
nearly 1/4 of the fish population was eliminated. After two years, there is only a
10% drop in the Catch per Ship, and almost 1/2 of the fish population is gone.
What is the major implication of this in the fishing industry?
1: FISH 2: Total Catch per Year
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Figure 12: Graph of the Connection System behavior
This graph shows the behavior of the connection subsystem. The graph shows the delay
between the FISH population and the Total Catch per Year.
3.4 Combining the Systems
You will need to close your model of the connection subsystem and open your
saved model of the fish and ships subsystems. It may be helpful to tear off the Appendix
and keep the picture of the final model handy for this part.
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