Choisy Marc, Rohani Pejman
Institute of Ecology, University of Georgia, Athens, GA 30602, USA.
Proc Biol Sci. 2006 Aug 22;273(1597):2025-34. doi: 10.1098/rspb.2006.3554.
Theoretical studies of wildlife population dynamics have proved insightful for sustainable management, where the principal aim is to maximize short-term yield, without risking population extinction. Surprisingly, infectious diseases have not been accounted for in harvest models, which is a major oversight because the consequences of parasites for host population dynamics are well-established. Here, we present a simple general model for a host species subject to density dependent reproduction and seasonal demography. We assume this host species is subject to infection by a strongly immunizing, directly transmitted pathogen. In this context, we show that the interaction between density dependent effects and harvesting can substantially increase both disease prevalence and the absolute number of infectious individuals. This effect clearly increases the risk of cross-species disease transmission into domestic and livestock populations. In addition, if the disease is associated with a risk of mortality, then the synergistic interaction between hunting and disease-induced death can increase the probability of host population extinction.
野生动物种群动态的理论研究已证明对可持续管理具有深刻见解，其主要目标是在不冒种群灭绝风险的情况下使短期产量最大化。令人惊讶的是，收获模型中并未考虑传染病因素，这是一个重大疏忽，因为寄生虫对宿主种群动态的影响已得到充分证实。在此，我们提出一个简单的通用模型，用于受密度依赖繁殖和季节性种群统计学影响的宿主物种。我们假设该宿主物种受到一种具有强免疫作用、直接传播的病原体感染。在此背景下，我们表明密度依赖效应与捕猎之间的相互作用会大幅增加疾病流行率以及感染个体的绝对数量。这种效应显然增加了跨物种疾病传播到家养和牲畜种群的风险。此外，如果该疾病与死亡风险相关，那么捕猎与疾病导致的死亡之间的协同相互作用会增加宿主种群灭绝的概率。
