Population recovery probabilities using a 5-stage-structured mathematical model and demographic stochasticity

A 5-stage-structured mathematical model (UDI: R4.x261.232:0001) was used to examine the recovery probabilities of a population after a time-varying environmental disaster. As a test case, stage-specific survival and transition rates, and annual fecundity values for the Gulf of Mexico sperm whales were used to model the lethal (reduction in survival rate) and sub-lethal (reduction in fecundity rates) impacts on population survival given demographic stochasticity. This analysis allows for the examination of the relationship between the DWH oil spill and the probability of population recovery to pre-disaster or biologically relevant levels under two conditions: probability of recovery in 10 years or 20 years post-disaster.

本研究采用五级结构数学模型（UDI: R4.x261.232:0001），旨在探析种群在经历时变环境灾害后的恢复概率。为验证模型适用性，本研究以墨西哥湾抹香鲸为案例样本，采集其阶段特异性存活率、转移率及年度繁殖力参数，构建模型以量化种群统计随机性背景下，灾害对种群存活的致死效应（存活率降低）与亚致死效应（繁殖率降低）的影响。本分析可用于探析深水地平线漏油事故（Deepwater Horizon，简称DWH）与种群恢复至灾前水平或生物学合理水平的概率之间的关联，设置两种情景：分别为灾害发生后10年或20年内实现种群恢复的概率。