“…Of special interest are periodic changes in environmental factors, which, in particular, may lead to periodic changes in the reproductive potential of populations with a seasonal reproduction pattern. This situation can be described using the Ricker equation with a periodic Malthusian parameter, which makes it possible to take into account the cyclical effects of both exogenous and endogenous factors on the population size (Shlyufman et al, 2016(Shlyufman et al, , 2017(Shlyufman et al, , 2018Frisman et al, 2019). The study showed that the Ricker equation with a Malthusian parameter varying with a period of two, along with the multistability of dynamic modes, also has phase multistability.…”