After having read all the posts, and then slept on it, here is my five cents worth......
1. The logistics of culling are now beyond consideration, the reasons are amply covered by several other posts.
2. Hwange is part of the megaherd range that extends across Botswana and into Namibia, SW Zambia and SE Angola, i.e. the KAZA TFCA. Culling (as it has in the past) creates a vacuum that will be filled by others from the megaherd - a common ecological occurrence. The rate of population increase after culling is as much a factor of stimulated breeding as it is immigration - at least in Hwange's case.
3. Point 2 makes the decision for culling on purely ecological grounds quite pointless. This begs the question....
4. Is the reason for culling then stimulated by the economic benefits it brings rather than the ecological benefits?
5. To date, I have yet to find CONCLUSIVE evidence that culling swings the ecological 'damage' in the opposite direction (please note the quotation marks. Damage is a human concept that Nature is quite unaware of). This despite Zimbabwe having culled more than 40,000 elephants since the inception of its culling policy.
6. Hwange is sadly reaping the consequences of the (at the time) ignorant, but well meaning, decision to place waterholes in what is effectively an extension of the Central Kalahari Game Reserve. If the TRUE desire is to relieve the browsing pressure (note, not damage) on Hwange's ecosystem, then the waterhole system has to be phased out and allow the park to revert (over time) to a CKGR type national park.
My mantra is that for every problem there is a solution, and I challenge the establishment to start looking and thinking out of the proverbial box. Globally, reductionism in wildlife management has nearly always led to ecological calamities. Shouldn't we be doing something else? Well someone is, and his name is Allan Savory. The man whose research developed the culling policy for Zimbabwe (then Rhodesia), now regrets his involvement and strives every day to change the long lasting effects it has had. Yes, he believes (as do I) that the culling of the 70's & 80's is the primary culprit for habitat degradation (I see the raised eyebrows). Watch his TED talk and check out the Savory Institute to get some idea of what he has achieved in 'healing land' using cattle (yes, cattle) in large numbers to mimic the large herds of herbivores that were also culled in an effort to eradicate FMD. You will be astounded. The Savory Insitute runs a research and teaching ranch outside Vic Falls call Dinamgombe Ranch. It sits neatly between Kazuma NP and the Chobe, right in the middle of prime elie country. What has been the result of his methods here? Erosion has been halted, rivers remain flowing, grass cover is ABUNDANT, browse is ABUNDANT, and wildlife numbers have increased, particularly elephant and buffalo. The problem he now faces is that he doesn't have enough cattle. That's right, the land needs even more herbivores to maintain its high rate of production.
Am I suggesting cattle are introduced to Hwange. Hell yes, why not? As I said we need to challenge the perceived norms. However, ONLY under the Savory model, not using current pastoralist practices. Think of the knock on effects to local villages and their economies. Suddenly the NP's become a true asset, not something that is elitist in the eyes of the locals. What about predators you ask? Well at Dinamgombe, there are more lions than in the whole of Kazuma NP (Savory pers comm.) and so far they have lost one cow, but they are producing a lot more calves, so it remains a net gain. Until such time as the mega herds of herbivores return to places like Hwange, why shouldn't we use cattle as surrogate healers?
On a final, personal, note. I find the concept of mass culling (elephants, seals, dolphins) despicable, and when it comes down to the crux of it, it is always driven by greed, not ecology. The ability of our species to inflict 'zooicide' (apparently genocide is only for humans and I don't think slaughter is definitive enough) is one of our most heinous attributes.
Now that I have effectively tossed a leopard amongst the guineafowl, let me sit back and watch the fallout....