Wildlife Fences Alter Ecosystems and Lead to Disappearance of Certain Species

Wildlife fences are constructed to protect wildlife from poachers, prevent the spread of diseases and lower the threat of human-wildlife conflict. Despite these conservation benefits, construction of fences should be considered as the last resort, according to a new finding.

The report documented in the journal Science, weighs the pros and cons of large scale fencing and claims that fencing has devastating environmental effects and costs a lot. The study emphasizes that fencing of wildlife should be avoided whenever possible.

"An increased awareness of the damage caused by fencing is leading to movements to remove fences instead of building more. Increasingly, fencing is seen as backwards step in conservation," says co-author Sarah Durant of ZSL's.

Contagious wildlife habitats that are converted into islands with the help of fencing pose a great threat to the small and isolated animal population. Such fencing makes the animals prone to extinction. This results in the loss of predators as well as other species and greatly influences the interaction between species and triggers a local extinction. The researchers term this process as 'ecological meltdown'.

"In some parts of the world, fencing is part of the culture of wildlife conservation - it's assumed that all wildlife areas have to be fenced. But fencing profoundly alters ecosystems, and can cause some species to disappear. We're asking that conservationists as well as other sectoral interests carefully weigh up the biodiversity costs and benefits of new and existing fences," ZSL's Rosie Woodroffe, lead author of the study, said in a statement.

Fences are mainly built to lower human-wildlife conflict. But in most cases they fail to deliver the same benefit.  What remains as a major challenge is the right fencing design, location, construction and maintenance. Sadly, in certain places these fences offer poachers a supply of wire for making snares.

Co-author Simon Hedges of WCS said, "A variety of alternative approaches - including better animal husbandry, community-based crop-guarding, insurance schemes, and wildlife-sensitive land-use planning - can be used to mitigate conflicts between people and wildlife without the need for fencing. WCS projects working with local people and government agencies have shown that human-elephant conflict can be dramatically reduced without using fences in countries as different as Indonesia and Tanzania."

Mainly in Southern Africa, there has been an extensive use of fencing system to create regions free from diseases such as foot and mouth diseases.  But some of these fences have led to devastating environmental effects. It is only with enhanced testing and vaccine people can curb the spread of such diseases and can do without fencing.

The rapidly changing climate elevates the need to provide wildlife with sufficient mobility and to maintain connectivity on land.