Paul James Haverkamp, Julian Klein, Michael Griesser

1. A high number of reproductive events is a critical fitness correlate for long-lived species. Thus, individuals of these species should be sensitive to factors that increase their mortality. Living in habitats with high exposure to predators can decrease lifespan, but the ecological drivers of longevity within populations remain poorly studied. Forest management in boreal forests can increase the predation risk by creating edges and open forests, which facilitate prey detection for visual hunters.
2. We assessed the impact of forest structure on breeding lifespan and lifetime reproductive success on a population of Siberian jays (Perisoreus infaustus) in northern Sweden located in managed and natural landscapes.
3. We used survival analyses to assess the influence of life history and ecological correlates on lifespan after attaining breeder status. The analyses included N=133 individuals within 38 territories in the managed landscape, and N=74 individuals within 25 territories in the natural landscape. The same correlates were used to investigate influences on the number of surviving offspring, as a measure of lifetime reproductive success.
4. Breeder lifespan was longest when individuals attained breeder status at an older age, in territories with dense understory, and few linear edges and natural openings, which reduce the risk of detection by primary predators (accipiter hawks). Moreover, a late onset of reproduction was associated with a higher lifetime reproductive success. Remarkably, these effects were only found in the managed landscape.
5. These results suggest that forestry shapes risk gradients in landscapes that particularly affect individuals that begin to breed at an earlier age. Thus, experience may be more critical to survive in managed than natural landscapes, making populations less resilient to disturbance and affecting life history evolution.