I agree on the Save Kudu observations. There's a lot of habitat there and littl pressure (the lions seem to get the ones with the biggest horns). I believe it's largely habitat - like whitetail in the US - they have a chance to get old and "grow horns."

I had no fewer than 5 over the course of a 2-week hunt that the PH said would go into the high 50's. These were largely Kudu we stumbled into, as we weren't really looking specificically for them.