<演講公告>A strong Allee effect and parasitoid aggregation in a discrete host–parasitoid system
講 題：A strong Allee effect and parasitoid aggregation in a discrete host–parasitoid system
講 師：Sophia Jang/ (Professor, Department of Mathematics and Statistics, Texas Tech University, USA)
時 間： 110 年 6 月 22日 (星期 二 ) 14:10-15:00
會議撥入號碼：(US) +1 929-236-4357
PIN 碼：931 952 947#
In this talk, we will introduce a discrete–time model of host–parasitoid interactions, where the host is subject to a strong Allee effect and the parasitoid is aggregated. The system may have multiple coexisting steady states and there are two host population thresholds. We discuss dynamical behavior of the model under different scenarios. In particular, the hosts become extinct if it is below the Allee threshold. The other threshold depends on the Allee threshold beyond which the host also becomes extinct due to overcompensated density dependence. When the initial host population size is between the two thresholds, we derive a critical parasitoid population size above which both populations become extinct. The critical size depends on the degree of aggregation of parasitoids. We conclude that aggregation of the parasitoid can promote population persistence when the host is subject to a strong Allee effect with a large Allee threshold. However, a more aggregated parasitoid population is more vulnerable to extinction if the growth rate of hosts is large.