### 4.3.4 Comments and exercises

The main point to remember is that the model predicts exponential growth even when the population is harvested.

Two following questions arise:

1. Is exponential growth on an on-going basis realistic?
2. Is the model that we have developed so far a "good" model in the sense that it enables you to predict with confidence the behaviour of the population of fish?

Evidently, the answer to these questions is "no".

Exercises

1. Obtain a difference model which includes harvesting at a constant level for every time period.
2. For the differential model, suggest harvesting strategies which may be more realistic than the constant rate used herein.