983

For Exercises 37–41, refer to the following. We suppose that a population has the reproduction curve shown in the accompanying figure, with units of thousands of tons of biomass. The mathematical description is that the population in the following year, , depends on the population in the current year (after any harvest) according to

for between 0 and 10, in units of millions of pounds. We start with a population this year whose value we can vary. (For these exercises, a spreadsheet or a programmable calculator is useful.)

image

Question 23.71

41. What is the equilibrium population size?

41.

We must have , or . The only solutions are and , or .