The Fence: Friend or Foe? Part 2

While in South Africa we spent time discussing the fences used around the national parks.  Many of them were electric fences because elephants would otherwise just knock them down with their bulk.  Fences were also put through rivers, across roads, and even through open savanna that may have been lacking in “development” but was still  not designated as part of the refuge and so was blocked off. 

The idea behind the fences here were interesting.  While talking to one of the guides he told us that, when people inquired about the fences, they were told the structures were there to keep the wildlife in and protect people.  But, he told us rather secretively, if you asked him, it was really to keep people out and protect the wildlife.  In all likelihood, it was probably a mix of the two.

People are often afraid of animals.  I’ve heard of city children that are absolutely terrified when they see their first cow.  People are afraid of a cheetah nabbing their children or a lion eating their goats or an elephant munching on their corn.  There are various ways to prevent this, of course, but for many people the easiest thing is to shoot the wildlife, or try to poison them, no questions asked.  Keeping wild animals in the preserve safeguards them from such behavior.  It is also a way to try and prevent poachers.  Fencing not only keeps the animals in, but helps keep the poachers out.  They still manage to find ways in, of course, but having a smaller area to survey does help rangers.  In addition, keeping wildlife in preserves gives them a designated area that is theirs alone, with little worry about invading humans using the area for the newest condo.

These wildlife preserves and national parks can make a huge difference in protecting species.  Sometimes a fence helps that.  If you are subscribed to my Twitter you may have seen the New York Times article I posted recently about the predator-proof fence put up across a piece of Oahu, a Hawaiian island.  The fence blocked off the Kaena Point Natural Area Reserve from the Kaena Point State Park. 

“Now, why would they want to do that?” you may be thinking.  To summarize the article, the birds of Hawaii were being ravaged by predators, most of which were introduced by humans.  Rats, cats, dogs, and mongoose were killing chicks, destroying eggs, and chasing adults.  The population was plummeting.  With the installation of the fence, however, the populations are taking off again.  The fence is as claimed, predator-proof.  After biologists and volunteers blocked the peninsula off and were able to go in and remove the predators, the area then became a safe refuge for birds to breed.

Not all fencing around preserves have such strongly positive impacts, however.  Kruger National Park has an overpopulation problem with their elephants.  African elephants are often killed by poachers for their tusks, so the successful breeding and reduction of poaching found in this park is an obvious benefit.  However, elephants are large creatures and have few natural predators.  A small calf may be stalked by lions, for example, but even that isn’t common because elephant herds are so protective of their young.  Hunter/gatherer humans would also on occasion hunt an elephant, but a single individual would provide so  much meat that such a large-scale hunt did not need to take place often.  One of the largest natural population controls for elephant populations is migration.  And now, with fences blocking the way, these animals cannot follow their instincts.

Migrations have generally occurred during the dry season of the area and the path taken is largely adhered to by the herd, a learned route passed down through the generations.  The path takes the family from area to area in search of food and watering holes.  The migration itself can be hundreds or even thousands of miles long and can be rough travel for very young, very old, sick or injured.  During very dry seasons there may not be enough food or water to ensure the health and survival of all members of the herd, and so many may perish along the way.

Keeping elephants in one area may seem like a good thing to some, as it prevents the long migration that may take the life of an elephant.  However, this cycle of life and death is necessary and healthy.  This is what the elephants evolved doing.  Restricting their movements to parks and preserves reduces their natural population controls, allowing for the population to get so large that the animals start destroying their habitat, and the habitat of others, as they strip vegetation in search of enough food to energize their huge bodies. 

Kruger is currently facing just a situation.  Their elephant population is double the recommended number of elephants for the area’s size and satisfactory methods of managing the population are still under discussion.  Chemical birth controls for over 14,000 elephants would be extremely difficult and expensive, yet the formerly used method of culling leads to public outcries.  With a fence preventing the normal population control method, what are we to do?