To be honest, its quite difficult to determine the real reason for the decline as many aspects are little understood. There is no doubt that a number of factors have played a role:
- Trophy hunting - yes, commercial hunting has had an impact, especially on predator populations in some areas. There were also a number of unscrupulous hunting companies that overshot quotas and abused the system.
- Citizen hunting - although not a recent factor, this had a massive impact in the past
- Poaching - this has been rife for many years, especially in hunting concessions where there was very little human footprint or management
- Fences - devastating
- Fire - this has had a very real impact on habitat degradation and therefore carrying capacity. The Okavango is a very nutrient poor environment, so any depletion at the lower level of the trophic pyramid will have a massive effect higher up.
- Human / wildlife conflict has had some role, although not massive
- Fluctuations in flood levels - these are natural cycles but relevant to some extent.
- Poor management - considering the wealth of the country and the value of tourism to the private sector it is surprising how badly the greater Okavango Delta has been managed over the last 30 years. Both government and the private sector are to blame for this.
So, in a nutshell we do not have enough historical data to fully understand the decline - what we need to focus on is ensuring that it now stops and hopefully reverses!