Eurasian lynx fitness shows little variation across Scandinavian human-dominated landscapes

José Vicente López-Bao,John Odden,Henrik Andrén,Jens Persson,Malin Aronsson,John D C Linnell

doi:10.1038/s41598-019-45569-2

Abstract

Despite extensive research on the ecology and behavioural adaptations of large carnivores in human-dominated landscapes, information about the fitness consequences of sharing landscapes is still limited. We assessed the variation in three consecutive components of female fitness: the probability of reproduction, litter size and juvenile survival in relation to environmental and human factors in a solitary carnivore, the Eurasian lynx (Lynx lynx), occurring in human-dominated landscapes in Scandinavia. We used demographic data from 57 radio-collared adult females between 1995–2011 (126 radio-years). Overall, the yearly probability of female reproduction was 0.80, mean litter size was 2.34 (range 1–4) and the probability to find a female that reproduced in the spring being accompanied by at least one offspring during the subsequent winter was 0.70. We did not find evidence that food availability was a key factor influencing female fitness. Female lynx may adapt to food availability when establishing their home ranges by adopting an obstinate strategy, ensuring a minimum amount of prey necessary for survival and reproduction even during periods of prey scarcity. In human-dominated landscapes, where sufficient prey are available for lynx, mortality risk may have a larger influence on lynx population dynamics compared to food availability. Our results suggest that lynx population dynamics in human-dominated landscapes may be mainly driven by human impacts on survival.

Highlights

In a human-dominated world[1], an increasing number of large carnivore populations occur in human-dominated environments[2,3,4], and there is accumulating evidence showing the ability of these species to persist in such landscapes[5,6]
Humans are the primary cause of large carnivore mortality, driving population dynamics and carnivore recovery[38,39,40,41], and a growing attention has emerged on how humans impact carnivore survival in relation to habitat[28,29]
In order to get a comprehensive perspective of the impact of humans on large carnivore persistence in human-dominated landscapes, it is crucial to understand how space use, and habitat selection, will affect fitness by relating environmental variation and human-related factors with different fitness components

Summary

Introduction

In a human-dominated world[1], an increasing number of large carnivore populations occur in human-dominated environments[2,3,4], and there is accumulating evidence showing the ability of these species to persist in such landscapes[5,6]. The heterogeneous distribution of human activities creates mosaics of factors influencing large carnivore persistence[22,23,24], such as heterogeneous distributions of food availability or mortality risk factors[25,26,27,28,29] Such spatial heterogeneity may have important consequences for population dynamics, triggering spatial patterns in carnivore occupancy, fitness and, carnivore persistence. We focused on three consecutive components of lynx female fitness in relation to environmental variation and human-related factors within their home ranges: (1) probability of reproduction, (2) litter size, and (3) juvenile survival to the first winter. We expected that factors associated with food availability should positively influence survival, whereas the opposite pattern should be observed for human-related variables[29,40]

Methods

Results

Conclusion