H.A.L. van Ginkel, MSc
Predation risk perceived by ungulates differs in space and time, resulting in relatively safe and unsafe areas and risky and less risky times. Ungulates constantly experience a trade-off between food availability and predation risk in which they often prefer low-quality but safe foraging areas over high-quality but risky foraging areas. In Yellowstone National Park, the introduction of wolves in 1994 led to the re-establishment of the landscape of fear for elk (Cerphus canadensis) and resulted in a recovery of palatable trees in more risky habitats due to reduced browsing. Thus far, the ecology of fear concept has mostly been applied to grassland or open woodland systems, while it has not received much attention from different environments, such as closed-canopy forests where these processes likely operate differently.
In the Białowieża Primeval Forest (BPF), Poland, multiple tree species have an inhibited regeneration, which is hypothesized to be the result of a high ungulate density. It has been demonstrated that for the palatable oak (Quercus robur), the few seedlings and saplings that are present are found in close association with coarse woody debris (CWD). Furthermore, tree seedlings and saplings have less browsing damage when associated with CWD, particularly in wolf-core areas (with high wolf-use), suggesting that the impact of CWD interacts with predator presence. This indicates that the landscape of fear concept can be applied to the BPF and that the ungulates (i.e. red deer (Cervus elaphus)) perceive foraging close to CWD as risky, because CWD can act as an escape impediment (blocking escape routes or view on approaching predators). The presence of CWD and predators are therefore important factors influencing patterns of red deer browsing. However, it is still unknown how CWD and predators affect different tree species. Therefore we will invest how tree regeneration is influenced by wolf presence, CWD and the preferability of the tree species in an experimental set-up.
|Last modified:||29 October 2018 10.58 a.m.|