Ecological Roles of Wolves
Large predators like wolves play an important role in maintaining the health of natural ecosystems but also shaping the ecosystem in which they live. As such they are a keystone species.
Wolves prey primarily on animals that are young or elderly, sick or injured, and weak or unfit, thus keep prey populations healthy. Wolf kills create an abundant and dependable food source for many other species. Researchers have documented wolf kills benefiting foxes, golden eagles, buzzards, ravens, magpies and at least 20 other species.
By preventing large herbivores, such as deer from becoming overpopulated wolves help maintain native biodiversity. Deer can overgraze their habitat when populations outgrow the carrying capacity of an ecosystem. This has been major issue in the Wye Valley and Forest of Dean, for instance. Overgrazing destroys the plant base, making the habitat less suitable for other species. By keeping deer and other ungulates moving (called the “ecology of fear”), they allow plant diversity to increase. Carcasses from wolf kills support other wildlife such as golden eagles, badgers and foxes. When grey wolves were reintroduced into Yellowstone National Park in 1995 after a 70-year absence, they began to restore ecosystems that had been degraded in their absence. There is a BBC video here which documents this impact.
Ten years after the first re-introduction of wolves to the Lake District we are already seeing the impacts the wolves have had in the national park.
What has been learnt from the Lakeland reintroduction
The Lake District is not a large area and can only sustain a single wolf pack. In order to supplement their food source they often have to leave the area. Wolves also need to move in the other direction, into the national park, in order that the genetic health of the pack is maintained. The Lake District in bounded, however, on one side by the sea and on the other by major roads, making this movement difficult. Proposals have been made to create safe, human free corridors to facilitate this movement.
Despite being established for ten years, the pack remains vulnerable as the loss of even a single breeding wolf will have a significant impact on the pack’s resilience. The Lakeland wolf education programme has shown considerable success in changing attitudes but many people still have a fear of wolves that can result in them being shot, poisoned, or harassed.
By protecting large, connected tracts of wild lands, we can be sure that wolves will have the space they need to provide these important ecosystem services without coming into conflict with people.