Restoring native predator populations could help to keep some of the most problematic invasive species around the world in check, according to a new study led by Queen’s University Belfast and Cornell University.
Invasive species are one of the greatest threats to biodiversity globally and are the main cause for the extinction of vertebrates in the last century, with an estimated cost of at least £133 billion/year.
Native predator populations have been depleted globally, despite being essential for the functioning of the ecosystem and biodiversity.
The absence of these predators facilitates the spread of invasive species, leading to the extinction of native species throughout the world.
The research, published today (Wednesday, June 16), in Global Change Biology, found that restoring native predators could provide a solution to a variety of the most damaging invasive species globally.
According to the study, the evolutionary naivety of invasive species to native predators, coupled with a lack of spatial refuges from predation, could underpin the abilities of native predators to provide effective control of certain established invasive species.
The research team has previously shown how the recovery of the native pine marten in the UK and Ireland has resulted in landscape-scale declines of the invasive grey squirrel.
Building on this research, the team has now evaluated native predator reintroduction and restoration as a viable nature-based solution to the invasive species crisis.
Lead author, Dr. Joshua Twining from the School of Biological Sciences at Queen’s University Belfast and the Department of Natural Resources at Cornell University, said:
“In a modern world that is daunted by environmental crisis and ecological collapse, it is more important than ever to realise the potential of restoring native predators to ecosystems from which they have been previously lost.
“This applies globally but is especially applicable in Britain and Ireland where we have persecuted all our large-bodied predators into extinction with no natural means of recovery.”
One example shows how re-introducing the native lynx could help to manage one of the most damaging invasive species to the environment in Europe, the sika deer.
Sika deer are considered a pest as they graze on crops and “ring” trees, stripping the bark from the base and causing the tree to die.
They are also thought to contribute to the spread of diseases such as bovine and avian tuberculosis (TB).
The new research provides evidence that the lynx could impact sika deer populations in Britain and Ireland.
It also shows how the lynx and wolf recovery in Europe could limit raccoon dogs below the threshold for rabies persistence, which remains a huge threat to human and animal health.