More frequent extreme climate events stabilize reindeer population dynamics

• DOI: 10.1038/s41467-019-09332-5
• Publication Date: 2019-04-08T10:04:10Z
• Authors: Brage B. Hansen; Marlène Gamelon; Steve D. Albon; Aline M. Lee; Audun Stien; R. Justin Irvine; Bernt-Erik Sæther; Leif E. Loe; Erik Ropstad; Vebjørn Veiberg; Vidar Grøtan
• Keywords: Density dependence; Population density; Extinction (optical mineralogy); Vital rates; Population model; Extreme Weather

Abstract Extreme climate events often cause population crashes but are difficult to account for in population-dynamic studies. Especially long-lived animals, density dependence and demography may induce lagged impacts of perturbations on growth. In Arctic ungulates, extreme rain-on-snow ice-locked pastures have led severe crashes, indicating that increasingly frequent could destabilize populations. Here, using empirically parameterized, stochastic models High-Arctic wild reindeer, we show more actually reduce extinction risk stabilize dynamics due interactions with age structure dependence. mainly suppress vital rates vulnerable ages at high densities, resulting a crash new state resilient reduced sensitivity subsequent icy winters. Thus, observed responses single poor predictors persistence because internal density-dependent feedbacks act as buffer against events.