Two Charles Darwin University academics have contributed to research released this week suggesting that the conservation of Africa’s lions could lie in improved fencing strategies.
CDU’s Research Institute for the Environment and Livelihoods Professor Stephen Garnett and The Northern Institute’s Senior Research Fellow Dr Kerstin Zander were part of an international team led by the University of Minnesota’s Professor Craig Packer. Their study, entitled “Conserving large carnivores: dollars and fence”, was published in the scientific journal Ecology Letters.
Professor Garnett said there was debate among conservationists as to whether the coexistence or physical separation of lions and humans was the best approach to their management in the wild.
“In the few extensive remote areas left in Africa, lions and people may be able to coexist,” Professor Garnett said.
“Sadly, as human populations rise, those of lions fall. Lions kill cattle or people and, in retribution, people kill more lions than breeding can replace.
“While lions can be guarded by rangers, fenced parks remove the direct source of conflict and are far more likely to have lion populations at target numbers.
“Loss of lions is bad for the whole ecology, because when the top predator is taken out, their prey becomes more common which leads to environmental issues such as over-grazing and erosion.
“It’s called a trophic cascade. We have seen it in Australia where baiting of dingoes has led to more feral cats and foxes, which have then wiped out populations of small native animals.”
Dr Zander said conservation efforts for unfenced lions were four times more expensive than that of fenced lions.
“Fenced reserves can maintain lions at 80 per cent of their potential population densities on annual management budgets of US$500 per km2,” Dr Zander said.
“Unfenced populations require budgets of more than US$2000 per km2 to reach half their potential densities.
“Finding funding has proved difficult, with only a small proportion of revenue generated by tourism being directly available to park managers, and trophy hunting rarely raising more than $1000 per km2.
“The bottom line is nearly half the unfenced lion populations will probably decline to near extinction over the next 20 – 40 years,” she said.