Exercise 2.5 A population of birds on an island has constant per capita birth (B) and death (u) rates. Also a constant number I of birds migrate to the island each year. Find the difference equation describing the growth of birds' population on this island, assuming that the newcomers start laying eggs only one year after arrival on the island.

Exercise 2.5 A population of birds on an island has constant per capita birth (B) and death (u) rates. Also a constant number I of birds migrate to the island each year. Find the difference equation describing the growth of birds' population on this island, assuming that the newcomers start laying eggs only one year after arrival on the island.