Appropriate choice of these parameters yield oscillatory behavior noted in the
lemming populations. For the results in Figs. 25.2 and 25.3, we have set A1 ¼ 0.9
(1/time period), A2 ¼ 0.5 (1/time period), B1 ¼ 0.9 (1/area/time period), B2 ¼ 0.2
(1/individuals/area/time period), and C1 ¼ 0.0043 (1/individuals/area/time period).
As in the previous chapter, introduce seasonality with random variations into the
model. Then find the parameters that yield oscillation of the lemming population.
Fig. 25.1
Fig. 25.2
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25 Lemming Population Dynamics