The White Rhino Population In South Africa: Some Speculative Observations. By David Cook and Bugs van Heerden.
Official statistics for 2017 released by the South African Dept. of Environment Affairs focus primarily on a minor decrease in rhino poached (1028 compared to 1054 the previous year) with the emphasis on a drop in Kruger National Park (KNP) poached rhino (down 24% to “just over 500”) but rather alarmingly a dramatic rise (to 222 – 37%) in poached rhino in the other formal stronghold of the species, centered on Hluhluwe-Imfolozi game reserve (HiP) in KwaZulu/Natal (KZN).
Private rhino owners (popularly acknowledged as holding some 6900 white rhino) suffered least with losses of 232 in comparison 160 the pervious year.
Noteworthy, is the increase in poaching in KZN. While in the case of KNP the question arises as to whether management have finally got their anti-poaching efforts under control, or whether they are simply running out of rhinos sending the poachers to target alternative areas – KZN in particular judging by the trend in numbers relative to previous years; is HiP the new KNP of poaching destinations?
But more worrying is the reliance on the total population counts for these two official strongholds when compiling national population statistics for South Africa, a subject which, for obvious reasons, are never officially cited. It begs the question; we may feel some relief at the news of an overall decrease in poached rhino but after 10 years and some 7 000 rhino in the ether, just how reliable are the benchmark population counts for the species and have all the extraneous factors – drought mortality and its effect on recruitment, confidence rating of the count methodology used to determine existing numbers, unfound poached rhino carcasses etc. – been taken into account. Poaching is not the only cause of rhino deaths.
For the sake of argument lets consider the possibility that the State Parks rhino numbers are less than their earlier estimates. In an article from oxpeckers in 2015 a vet in Kruger Park, Dr Kobus du Toit, challenged the population estimates in Kruger, and calculated taking into account reproductive rates, sales of rhino on auction and, of course poaching, that there were only 1500 and 3000 rhino in the park! At the time Kruger Park claimed that the population was between 8 000 and 11 000. Sustained poaching since du Toits 2015 calculations would have either reduced that number or kept it the same – depending on what the actual population was at the time.
Private rhino owners are relatively confident that they speak for 6 900 rhinos in 2017 and in 2016 of the 1 054 rhinos killed 160 were on private reserves. Based on this and the 2016 private rhino population estimate of 6 500 ( considered accurate), that represents a net loss of 2.46%, and if rhino natural population growth is 8%pa then there has been a net population increase of about 5.54% after the losses to poaching. But it is also well known that privately ranched rhinos productivity is a bit higher than 8%, in some cases over 10% pa.
Now, if private rhinos make up a third of the national herd as is often cited, then the national herd would stand at 13 000 and 2016 would have seen 894 killed by poachers – that’s about 6.9% of the population killed in a single year. Which is very close to a net decline – IF ONE ACCEPTS THE STATE RHINO NUMBERS – THE VAST BULK OF WHICH ARE IN TWO PARKS IN KZN THE OTHER KRUGER PARK – are as high as 13 000.
But what if State Parks don’t have 13 000 rhinos? What if we used a number half-way between the Kruger Parks’ estimate and Dr. du Toits estimates from 2015? – that would have meant that Kruger Park had closer to 5000 rhino and not 8000 as they claim. If the number were 5000, then there is no doubt that the numbers would have been in decline since 2015.
Lets not forget the crippling drought in 2016. How many rhino perished and how was reproduction due to infant mortality etc effected remains unknown? We know neighbouring Swaziland, in more or less the same bioclimatic zone as Kruger Park suffered heavy losses despite the fact that they imported tons of feed supplement for starving animals.
Count methodology and efficiency also plays a vital part in determining the size of a population of large mammals. Firstly, in a large park such as KNP it is understood that from a logistical and cost effectiveness perspective aerial block sampling is used i.e. rhino in a block are counted and the results extrapolated for rhino occurrence in an adjacent block. Count efficiency i.e. the skill and observer expertise of the airborne counters is also essential. A common error is to fly a grid, count the rhino then on the return flight count the same rhino, which had moved into a different locality in the meantime.
In HiP in the 1970’s population censusing was vital and a high priority annual event in which certain skilled observers and pilot experience a prerequisite in what was generally regarded as necessary to achieve a 85 to 90% confidence rating. The whole 100 000 ha of reserve was counted – no sampling was necessary as is the case with KNP.
Just how accurate the current population estimates are for Hluhluwe/ Imfolozi is also debateable. An official figure is not available but sources reveal that the figure derived from a helicopter grid census in 2016 was some 1450 white rhino, with 2017’s losses yet to be taken into account.
Factoring all this into the equation, it is not unreasonable to suggest that private rhino owners may speak for more than 40% of South Africa’s rhinos with the state parks numbers in catastrophic decline.
Sooner or later, an accurate, reliable figure for the total white rhino population in South Africa will be revealed – it may make interesting, if anything, depressing reading when it finally dawns on the public that the war is fast being lost rather than won.
And all the while on the table these past dreadful years lies an alternative plan gathering dust – a legal trade in legal rhino horn with Far eastern partners. Feebly avoided by DEA at the last CITES CoP in Johannesburg in 2016 it was left to the private rhino owning sector to press home a high court judgement enabling domestic sales of rhino horn, a brave move challenged every step of the way by the very same DEA which latterly have been reported boasting about empowering rural communities through sustainable use wildlife practices in the Eastern Cape.
How different might things have been for rural people – and for rhino- had we hammered home our unrivalled advantage at CITES and given fresh life to rhino conservation via a regulated export market.
Bugs van Heerden