Question

3. (12 marks) In a large reserve in western Canada, a bear population eats salmon from the rivers in the reserve. The populations of salmon and bears can be described with the following model dS -bSB dt d B dt where S is the population of salmon, B is the population of bears, and a, b, K, c, and d are positive constants. The time t is measured in years (a) Describe the physical significance of each term in the system (b) What is the long-term behaviour of the salmon population on the reserve if the initial bear population is zero!? (c) Suppose that fishing is introduced to the reserve, resulting in N salmon being harvested per year. How might you alter the model to reflect this? (d) Briefly describe (i.e., in one or two paragraphs) some methods you could use to analyse these equations to get information about solutions to the model

Answer 1

cat Nata ir due to tUe ds oft mon twiih pen yen hen

tom bohaviusr h con usephase pone t analyze the long Tanm riss wayǐouh' we Can oho 요d the equil.la l'um0