Harvest optimization for Rikker's population, when environment parameters limiting population growth change cyclically

In this paper the problem of optimal harvest from Rikker's population is solved provided that harvest rate is determined by population size and environment parameters limiting population growth change cyclically.
It is shown, that for these populations the optimal harvest rate is determined by the amplitude of parameters variation, while the optimal harvest rate policy is to alternate years of intensive harvesting with the years of negligibly small harvesting