Population dynamics

ANALYSIS OF ATTRACTORS FOR STOCHASTICALLY FORCED «PREDATOR–PREY» MODEL

We consider the population dynamics model «predator–prey». Equilibria and limit cycles of system are studied from both deterministic and stochastic points of view. Probabilistic properties of stochastic trajectories are investigated on the base of stochastic sensitivity function technique. The possibilities of stochastic sensitivity function to analyse details and thin features of stochastic attractors are demonstrated.

STOCHASTIC SENSITIVITY OF LIMIT CYCLES FOR «PREDATOR – TWO PREYS» MODEL

We consider the population dynamics model «predator – two preys». A deterministic stability of limit cycles of this three­dimensional model in a period doubling bifurcations zone at the transition from an order to chaos is investigated. Stochastic sensitivity of cycles for additive and parametrical random disturbances is analyzed with the help of stochastic sensitivity function technique. Thin effects of stochastic influences are demonstrated. Growth of stochastic sensitivity of cycles for period doubling under transition from order to chaos is shown.

SYNCHRONIZING THE PERIOD­2 CYCLE IN THE SYSTEM OF SYMMETRICAL COUPLED POPULATIONS WITH STOCK–RECRUITMENT BASED ON THE RICKER POPULATION MODEL

We investigated coupled map lattices based on the Ricker model that describes the spatial dynamics of heterogeneous populations represented by two connected groups of individuals with a migration interaction between them. Bifurcation mechanisms in­phase and antiphase synchronization of multistability regimes were considered in such systems. To identify a synchronization mode we introduced the quantitative measure of synchronization.