OK . . . here is another perspective from somebody who lived in Africa and have seen the impact of elephants on the environment.
During my early years visits to the Kruger National Park, the most abundant wildlife would be the Impala . . . . and on game drives would get bored with impala after impala after impala . . . big herds!!! Lots of excitement was generated whenever we were fortunate to see an elephant, or a small herd. This was back in the late 80's.
Step forward to 2008 - we were fortunate to go 'back home' and visit family in South Africa . . . and part of the trip was a weekend safari stay in a fairly exclusive private game reserve adjacent to the Kruger National Park and within the Timbavati reserve area.
On our very first game drive, I was shocked to see how decimated the trees and grasslands were . . from overgrazing by elephants. You have to know how elephants graze and how they will totally destroy a tree to get to the soft green leaves. AND . . they have voracious appetites.
During this weekend visit, my new wife, who is a lovely born and bred American gal, was initially in awe when we spotted our first herd of elephants . . right across the river from our tent bungalow. . . . . . by the end of the weekend . . . we were as bored with elephant viewing, as we were with the abundant impala.
There are just too many of them and they are destroying the landscape, to the detriment of all the other plant eating wildlife sharing the same grazing.
According to our guide on the game drives, the South African authorities are planning on re-instituting controlled elephant culling and/or capture and relocation to less populated wilderness areas.
By the way . . . elephant biltong (jerky) is yummy.