Now your model is built, you can set about making some variations to it.

You can download a copy of the completed model here.

Using your model, try out some of the following:

Think of a question of your own that you could use your model to answer.

In what ways is your model different from the situation of Devils in the real world?  What factors are missing that might be important? 

Extension

Add in a Devil breeding program, so that healthy Devils can reproduce.  You can get some ideas about how to set up breeding from the Fish and Plankton example that comes packaged with Starlogo TNG.