Synergistic effects of predation and parasites on the overwinter survival of root voles

摘要: Predators and parasites have been important extrinsic factors influencing the fluctuation of small mammal populations. They can non-additive effects on a shared group preys or hosts, which consequences for population dynamics. However, experimental studies incorporating interactions between predation are scarce in Here we systematically examined synergistic predators coccidian interaction overwinter survival likely mechanisms underlying root vole (Microtus oeconomus). Our aim was to test general hypothesis that coccidia interact synergistically decrease voles through mediating vole’s physiological traits body conditions. We carried out factorial design, by manipulated predator exclusion combination with parasitic removal enclosures, then measured fecal corticosterone metabolite (FCM) levels, immunocompetence, conditions captured animals via repeated live trapping. found strong negative effect survival. Importantly, increased both prevalence intensity infection immune suppression induced stress, while reduced plasma protein hematocrit level voles, may impair anti-predator ability lead an increase predation. finding showed when exposed risk infection, their greatly reduce density. This be mechanism dynamics mammals.