To underpin the concern that environmental change can flip an ecosystem from stable persistence to sudden total collapse, we consider a class of so-called ecoepidemic models, predator – prey/host – parasite systems, in which a base species is prey to a predator species and host to a micro-parasite species. Our model uses generalized frequency-dependent incidence for the disease transmission and mass action kinetics for predation.We show that a large variety of dynamics can arise, ranging from dynamic persistence of all three species to either total ecosystem collapse caused by high transmissibility of the parasite on the one hand or to parasite extinction and prey-predator survival due to low parasite transmissibility on the other hand. We identify a threshold parameter (tipping number) for the transition of the ecosystem from uniform prey/host persistence to total extinction under suitable initial conditions.

中文翻译：

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捕食者–猎物/宿主–寄生虫：均质感染发病率下的脆弱的生态流行系统

为了强调环境变化可能将生态系统从稳定的持久性转变为突然的整体崩溃的担忧，我们考虑一类所谓的生态流行模型，即捕食者－猎物/宿主－寄生虫系统，其中基础物种是捕食者物种的猎物并拥有微寄生物种。我们的模型使用了与疾病传播有关的广义频率相关性发生率和对捕食行为的整体作用动力学，研究表明可以产生多种动力学，从这三种物种的动态持久性到由于寄生虫的高传播性导致的整个生态系统崩溃一方面是由于寄生虫的低传播性导致寄生虫的灭绝和捕食者的生存。