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Elephant Culling in KNP - Your views

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Richprins

The Force is weak in this one

Unread post by Richprins » Fri May 14, 2010 6:33 pm

yoda wrote:(This above bit was meant to be in the quote, but I appear to have done something wrong- Yoda)


It appears not proficient enough, you be! Training it is you need!

Elephants and human populations sometimes co-exist quite well in some spots in the rest of Africa.

However, these ellie populations are normally quite small and localised, and try to avoid humans as they are regularly poached.

Conflict occurs when food and water become scarce.

For example, the Masai-Mara is unfenced, and contains a significant number of humans.

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Re: The Force is weak in this one

Unread post by Yoda » Sun May 16, 2010 6:59 pm

Richprins wrote:
yoda wrote:(This above bit was meant to be in the quote, but I appear to have done something wrong- Yoda)


It appears not proficient enough, you be! Training it is you need!

Elephants and human populations sometimes co-exist quite well in some spots in the rest of Africa.

However, these ellie populations are normally quite small and localised, and try to avoid humans as they are regularly poached.

Conflict occurs when food and water become scarce.

For example, the Masai-Mara is unfenced, and contains a significant number of humans.


Rich, I may be a Jedi Master, but there is always much to learn.

My understanding is that the Masai are a society who's lives revolve around their cattle. And it is in their best interests to keep poachers off their lands.

I think the main problem occurs with subsistance farming. Elephants clearly view a field of mielies as a nice snack. And then the trouble starts.

I don't know much about the people living around Massinga. But they have already made their feelings known that they don't want the Elephants.

Thanks
Yoda

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Re: Elephant Culling in KNP - Your views

Unread post by TheunsH » Thu Jul 15, 2010 1:53 pm

Any news on the culling of the 6000 surplus elephants in Kruger? :hmz:

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Re: Elephant Culling in KNP - Your views

Unread post by Groovy » Thu Oct 07, 2010 9:00 am

I together with 8 of our guides attended a talk by Prof. Van Aarde of Pretoria University last night. It was arranged by IFAW (International fund for animal welfare) in conjunction with Ecotraining. This most interesting talk, giving to many Facts and taking down many of the Fables about elephants and their plight for survival. It was extremely well supported (200 +) and the proceeds of the function will be going to the Kruger Anti poaching unit in the form of equipments and supplies.

I would imagine the booklet with a huge amount of info is available from IFAW, I would imagine it best contact them for a copy. If you get a chance you must sit down for the 45 minutes/hour and listen to what the man has to say.

Enlightening interesting to the point and I believe a great step forward in the "management" or "non management" of elephants whoch are part of the African continents heritage.

From what I can read (and this is my opinion not that of the prof) into the whole debate/subject elephants wont be culled in the near future, and if they do get culled then it will and can only be for financial short term gain, by and for whoever does the culling.

Have a great day, the lowveld is cool damp and overcast, hopefully the signs of our first rains.

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Re: Elephant Culling in KNP - Your views

Unread post by Ferdelance » Fri Oct 08, 2010 11:40 pm

Coming from the Kruger just recently and having spoken to some of the Guides there that seems to be the consensus now in the Kruger, what Groovy mentioned, that the birth rate has stabalized and they will now wait and see if nature doesn't sort itself out.

However anyone who's been in Chobe knows excactly what Ele's can do if not managed and fear we are going that way in the KNP. The destruction by the ele's on the bush is very visible. They have no where to go as the Kruger is not the mara and has a fence. This is why, for example, Hlanganini is now dead. To many big bulls on one spot, coupled with musth and the fights become deadly.

I love the big bulls very much but not dead. I don't think we even know the full impact yet. White backed vultures losing their nesting sites as all the big trees get knocked down for example.
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Re: Elephant Culling in KNP - Your views

Unread post by Imberbe » Fri Oct 08, 2010 11:56 pm

Groovy wrote:I together with 8 of our guides attended a talk by Prof. Van Aarde of Pretoria University last night. It was arranged by IFAW (International fund for animal welfare) in conjunction with Ecotraining. This most interesting talk, giving to many Facts and taking down many of the Fables about elephants and their plight for survival. It was extremely well supported (200 +) and the proceeds of the function will be going to the Kruger Anti poaching unit in the form of equipments and supplies.

I would imagine the booklet with a huge amount of info is available from IFAW, I would imagine it best contact them for a copy. If you get a chance you must sit down for the 45 minutes/hour and listen to what the man has to say.

Enlightening interesting to the point and I believe a great step forward in the "management" or "non management" of elephants whoch are part of the African continents heritage.

From what I can read (and this is my opinion not that of the prof) into the whole debate/subject elephants wont be culled in the near future, and if they do get culled then it will and can only be for financial short term gain, by and for whoever does the culling.
...


The problem with IFAW is that it is an animal rights organization. Though they do some great work, I don't believe that their approach is neutral, and I am not at all convinced by their booklet. It is pure promotion of their point of view. It is their right to do so, and to promote their ideas, but I don't think it is balanced, nor very realistic in some aspects. They are banking on increasing the land available for elephants, sadly, given the political and economical realities of our region, this is very optimistic.

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Re: Elephant Culling in KNP - Your views

Unread post by Bush Baptist » Sat Oct 09, 2010 8:35 am

Imberbe :thumbs_up:
Whatever (according to BB): "You are correct but I don't want to admit it".

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Richprins

Re: Elephant Culling in KNP - Your views

Unread post by Richprins » Sun Oct 10, 2010 6:19 pm

Thanks very much, Groovy! :thumbs_up:

Prof. Van Aarde has taken an anti-culling stance a long time ago, and some of his theories have been mentioned before on this thread...

Not all scientists agree, by a long shot! :big_eyes:

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Re: Elephant Culling in KNP - Your views

Unread post by RUMURUTI » Sun Oct 10, 2010 7:07 pm

RP, just wanted to say something on the Maasai in Kenya.
While in Masai Mara they have become convinced conservationists we have exactly the opposite in Amboseli.
The Mara Maasai are now part of a global wildlife conservation project and seems to work. On the other hand the Amboseli ones are fighting for the little water available, which is in the park!, and it will take a lot of hard work to convince them that protecting wildlife is to their advantage.

Elephant poaching in Kenya is present but is mainly in the northern areas, northern part of Tsavo, Meru, Isiolo, Samburu and so on, and mainly done by poachers of Somali origin.
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Richprins

Re: Elephant Culling in KNP - Your views

Unread post by Richprins » Sun Oct 10, 2010 9:38 pm

Thanks, Andy! :thumbs_up:

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Re: Elephant Culling in KNP - Your views

Unread post by Groovy » Wed Oct 13, 2010 7:18 am

Just when you think.....

My thoughts with posting the report on Prof.Van Aarde's talk was purely the fact is , none of us want to see elephants shot, just the trauma that elephant family units have to go through should be enough to stop it totally.

I look at it from another side, the guys on the ground who actually have to do the job(albeit an excellent job, trying to be as humane as possibleunder circumstances) , I dont think any of us think its great to do that job, nope I doubt it. Having been in the hunting industry many years ago now(dont say to loudly but 25 years is a long time in my book), I always had a love hate relationship with that part of my life. As I grew older and wiser the picture became clearer, and I read some thing yesterday

Conservation - its not something we inherit from our parents, but something we borrow from our children........

Anyway off to Kruger, camping for a couple of days, see ya Friday

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Re: Elephant Culling in KNP - Your views

Unread post by Imberbe » Wed Oct 13, 2010 8:54 am

True - Culling is no joke, it is a very serious measure that has a huge impact on all affected parties.

Enjoy your trip! :thumbs_up:
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Richprins

Re: Elephant Culling in KNP - Your views

Unread post by Richprins » Wed Dec 15, 2010 5:22 pm

viewtopic.php?f=73&t=49503


More elephant culling info next year! :evil:

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Re: Elephant Culling in KNP - Your views

Unread post by gmlsmit » Fri Dec 24, 2010 6:00 pm

Here is an extract from a 1999 paper by Prof van Aarde

Animal Conservation (1999) 2, 287–294 © 1999 The Zoological Society of London Printed in the United Kingdom


Culling and the dynamics of the Kruger National Park African elephant population


INTRODUCTION

For 30 years, managers have promoted culling as a management tool for African elephant populations confined to areas set aside for conservation (e.g. Buechner et al.,
1963; Glover, 1963). Based on the findings of Van Wyk & Fairall (1969), the South African National Parks Board initiated a programme of elephant culling as a means of curtailing the anticipated destruction of the vegetation in the Kruger National Park (KNP). In 1967, they had already decided to maintain the KNP population at about 7000 individuals (0.32 elephants/km2 (based on studies on plant–elephant interactions conducted elsewhere in Africa. A new master plan for the management of the KNP came into effect during 1986. It confirmed the decision to continue to keep the population at 7000, but accepted fluctuations ranging from 6000 to 8500 individuals (Joubert, 1986). That decision resulted in 17 219 elephants being culled or removed
from the KNP between 1967 and 1996. Increasing public pressure and the lack of proof of the damaging effects of high elephant densities resulted in the culling being
temporarily discontinued in 1995. Since then, however, Cumming et al. (1997 and references therein) have demonstrated how high densities dramatically reduce
biological diversity.

The ‘elephants versus biodiversity’ debate remains controversial.
Animal Conservation (1999) 2, 287–294 © 1999 The Zoological Society of London Printed in the United Kingdom.

Rudi van Aarde 1 , Ian Whyte 2 and Stuart Pimm3
1 Department of Zoology and Entomology, The University of Pretoria, Pretoria 0002, South Africa 2 Kruger National Park, Private Bag X402, Skukuza 1350, South Africa
3 Department of Ecology and Evolutionary Biology, The University of Tennessee, Knoxville TN 37996, USA.

(Received 22 July 1998; accepted 6 April 1999)

Abstract South Africa’s National Parks Board has opted to control African elephants (Loxodonta africana) through culling in the Kruger National Park (KNP). Killing elephants is highly controversial. The Board must balance this controversy against the probable destruction of vegetation and the consequent depletion of biological diversity that high elephant densities cause. Annual aerial counts provided the population estimates on which the culling quotas were based. For management purposes, the elephant population of the Park is divided into four sub-populations. From 1984 to 1994, the annual quota was usually taken from only one of these sub-populations during a given year. This resulted in 3 to 5 years elapsing between culls in each sub-population. We investigated the year-toyear changes in densities after culling. These changes were density dependent. Density dependence implies that immediate culls following estimated high densities may be premature. If left alone, the densities would decline naturally. Indeed, culling becomes self-reinforcing as it moves population densities towards the level where reproduction is greatest. Data confirm this intuition: at densities greater than 0.37 elephants/km2 elephant numbers generally declined without culling. Many culls were unnecessary. Culling, as implemented in the past, may have had consequences for elephants and their
habitat that were different to those expected from a mere reduction in their numbers. Densities in the year immediately after a cull tended to decline – not increase as would be expected from density dependence alone. Undoubtedly, this unexpected decline was the consequence of disturbance and subsequent emigration. In following years, the densities rose as animals moved back into the sub-population. A management programme where culling will be instituted only when densities exceed 0.37 elephants/km2 in selected regions in the park for at least 1 year, may be more acceptable than the programme used up to 1995. However, we do not know if the vegetation of KNP can withstand the resulting episodic high densities. With densities presently exceeding the cut-off values calculated for both the south and the northern management regions vegetation changes there need to be monitored.

All correspondence to: Rudi van Aarde. Tel: +27 12 4202753;
Fax: +27 12 362 5242; E-mail: rjvanaarde@zoology.up.ac.za.Annual aerial surveys provided the culling quotas needed to maintain elephant densities within the suggested range. From 1967 to 1984 elephants were culled from areas throughout the KNP, however, from 1985 to 1994, KNP staff identified four management regions separated by rivers and covering the park’s entire area (Fig. 1). The total quota for a given year was taken from just one of these regions and meant removal of between 6 to 32% of the local population.

We examined the response of elephants to culling by determining how post-culling densities affected population growth rate. Our analyses suggest an alternative
management strategy for the elephants in the KNP. Left alone, high densities of elephants will usually decline. There will often, but perhaps not always, be no need for human intervention.

MATERIALS AND METHODS

Censuses

We base our analyses on information collected as part of the conservation management operations of the KNP. Aerial surveys conducted over a period of 1month during August and September, when elephants concentrate along the watercourses of the park, yielded annual population estimates for the period from 1967 to 1998. Visibility is also at its best at the end of the austral winter
when most deciduous trees have shed their leaves. A four-seater Bell 206 Jet Ranger helicopter flown at an altitude of between 200 and 300 m, depending on the
terrain and visibility permitted visual coverage of about 1 km on each side of the aircraft. Flight paths followed the drainage courses throughout the park. With flight
lines less than 2 km apart, the entire park was covered during each census. The hovering ability of the helicopter allowed for counting of each group encountered,
with the final number obtained through consensus amongst three observers. These yearly counts lasted 18 days, with an area of approximately 1100 km2 being covered each day at a search rate of 2.6 km2 /min. I. Whyte (pers. obs.) has reported the precision and accuracy of these counts. Differences between recorded and expected population sizes over a period of 15 years only twice exceeded 6% (mean (± SE) = 1.67 (± 1.13)%).

Culling

Annual culling quotas ranged from 16 to 1846 individuals. Between 1967 and 1984, culls took place throughout the park. From 1984 to 1994, the total quota each year rotated around the four management regions in the KNP (Fig. 1). In practice, this resulted in 3–5 years elapsing between culls of a population in a given region.
As a result of this, and of the discontinuation of the culling programme since 1995, a specific region experienced from 1–7 years of no disruption by culling after a specific cull. We refer to each of these regions as a sub-population.
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Re: Elephant Culling in KNP - Your views

Unread post by gmlsmit » Fri Dec 24, 2010 6:13 pm

RESULTS

Population growth


Culling did not halt population growth for elephants in the KNP, which fluctuated between 6586 and 8821 animals. Successive years of decrease in numbers were followed by successive years of increase in numbers (Fig. 2). The fraction of the total population removed through culling during a given year ranged from 0.2% to 20.9%. Expressed as a fraction of the sub-population affected by a given cull, the values ranged from 5.9 to 31.6%.

Table 1 presents the annual population density before and after culling.

Table 1.

Annual population density, culling density and change in population density expressed as the difference between post-cull density and the density after a cull for the four management districts of the KNP. Density (elephants/km–2 per Management district (area).

Legend

AAA= Year.
BBB = Density year before cull.
CCC= Culled density.
DDD= Density after cull
EEE= A +1 (after cull)
FFF = Change in density (D-E)

Far North (4190 km2)

AAA – BB B – CCC – DDD – EEE - FFF

1984 - 0.522 - 0.165 - 0.357 - 0.227 - -0.130
1985 - 0.227 - 0.000 - 0.227 - 0.268 - + 0.041
1986 - 0.268 - 0.000 - 0.268 - 0.237 - -0.031
1987 - 0.237 - 0.000 - 0.237 - 0.264 - +0.026
1988 - 0.264 - 0.000 - 0.264 - 0.372 - + 0.108
1989 - 0.372 - 0.074 - 0.298 - 0.232 - -0.066
1990 - 0.232 - 0.000 - 0.232 - 0.346 - +0.114
1991 - 0.346 - 0.000 - 0.346 - 0.363 - +0.018
1992 - 0.363 – 0.000 - 0.363 - 0.351 - –0.012
1993 - 0.351 - 0.062 - 0.289 - 0.298 - + 0.009
1994 - 0.298 - 0.010 - 0.289 - 0.275 - –0.014
1995 - 0.275 - 0.000 - 0.275 - 0.284 - + 0.009
1996 - 0.284 - 0.000 - 0.284 - 0.267 - –0.016
1997 - 0.267- 0.000 - 0.267 - 0.308 - + 0.041
1998 - 0.308 - 0.000 - 0.308 –

North (5980 km2)

AAA – BB B – CCC – DDD – EEE - FFF

1984 - .324 - 0.035 - 0.289 - 0.335 - +0.047
1985 - 0.335 - 0.020 - 0.316 - 0.308 - –0.008
1986 - 0.308 - 0.000 - 0.308 - 0.359 - +0.051
1987 - 0.359 - 0.000 - 0.359 - 0.362 - +0.003
1988 - 0.362 - 0.046 - 0.316 - 0.257 - –0.059
1989 - 0.257 - 0.000 - 0.257 - 0.358 - +0.101
1990 - 0.358 - 0.000 - 0.358 - 0.312 - –0.045
1991 - 0.312 - 0.000 - 0.312 - 0.330 - +0.017
1992 - 0.330 - 0.051 - 0.279 - 0.281 - +0.002
1993 - 0.281 - 0.000 - 0.281 - 0.317 - +0.036
1994 - 0.317 - 0.000 - 0.317 - 0.369 - +0.053
1995 - 0.369 - 0.000 - 0.369 - 0.392 - +0.022
1996 - 0.392 - 0.000 - 0.392 - 0.401 - +0.009
1997 - 0.401 - 0.000 - 0.401 - 0.458 - +0.057
1998 0.458 0.000 0.458 –

Central (5475 km2)

AAA – BB B – CCC – DDD – EEE - FFF

1984 - 0.342 - 0.022 - 0.320 - 0.354 - +0.034
1985 - 0.354 - 0.000 - 0.354 - 0.389 -+0.035
1986 - 0.389 - 0.070 - 0.319 - 0.245 - –0.075
1987 - 0.303 - 0.000 - 0.303 - 0.322 - +0.019
1989 - 0.322 - 0.000 - 0.322 - 0.266 - –0.056
1990 - 0.266 - 0.000 - 0.266 - 0.256 - –0.011
1991 - 0.256 - 0.057 - 0.198 - 0.304 - +0.105
1992 - 0.304 - 0.000 - 0.304 - 0.365 - +0.061
1993 - 0.365 - 0.000 - 0.365 - 0.352 - –0.013
1994 - 0.352 - 0.000 - 0.352 - 0.333 - –0.019
1995 - 0.333 - 0.000 - 0.333 - 0.341 - +0.009
1996 - 0.341 - 0.000 - 0.341 - 0.315 - –0.027
1997 - 0.315 - 0.000 - 0.315 - 0.322 - +0.007
1998 - 0.322 - 0.000 - 0.322

South (3840 km2)

AAA – BB B – CCC – DDD – EEE - FFF

1984 - 0.326 - 0.0490 - 0.277 - 0.221 - –0.056
1985 - 0.221 - 0.000 - 0.221 - 0.379 - +0.158
1986 - 0.379 - 0.000 - 0.379 - 0.326 - –0.053
1987 - 0.326 - 0.066 - 0.260 - 0.330 - +0.071
1988 - 0.330 - 0.009 - 0.322 - 0.366 - +0.045
1989 - 0.366 - 0.000 - 0.366 - 0.393 - +0.027
1990 - 0.393 - 0.081 - 0.312 - 0.400 - +0.088
1991 - 0.400 - 0.000 - 0.400 - 0.360 - –0.041
1992 - 0.360 - 0.000 - 0.360 - 0.370 - +0.011
1993 - 0.370 - 0.060 - 0.311 - 0.393 - +0.082
1994 - 0.393 - 0.033 - 0.360 - 0.449 - +0.090
1995 - 0.449 - 0.000 - 0.449 - 0.477 - +0.027
1996 - 0.477 - 0.000 - 0.477 - 0.514 - +0.037
1997 - 0.514 - 0.000 - 0.514 - 0.485 - –0.029
1998 - 0.485 - 0.000 - 0.485

Annual counts were conducted during August/September of year t while culling took place during April/May of year t+1. Entry of these values in the same row facilitated
further calculations.

DISCUSSION

Culling raises ethical, social, and economic problems (see Cumming et al., 1997; Butler, 1998; Whyte, van Aarde & Pimm, 1998) well beyond the scope of this paper. But so, too, does the loss of biodiversity. The South African National Parks aims to maintain biodiversity by preventing habitat destruction. The culling of elephants from 1967 to 1994 kept the population at between 7000 and 8500 individuals and thus within the apparent limits of accepted influence on their environment in the KNP.

The obvious questions are was this the right range of population densities and was the management plan the best way to achieve that range?

Is the right range of densities correct?

The practice of limiting culling to a given area, followed by a number of years of no culling in that area, provided us with the opportunity for assessing the response of subpopulations to culling. From our analyses it is apparent that numerical changes in elephant sub-populations in the KNP are density dependent. At densities >0.374 elephants/km2 (Fig. 3) the population tended to decrease.

This value might differ for the different management regions of the KNP (see Table 2). This density is equivalent to an elephant population of very nearly 8000 for the KNP, and thus within the limits set for the population by park managers (see Smuts, 1975; Joubert, 1986).

Density induced regulation of reproductive output through changes in age at sexual maturity, pregnancy rates and inter-calving interval have been recorded for elephants elsewhere in Africa (see Laws, 1969; Dunham, 1988; Dobson, 1993, and references therein). Such density dependence may be important in population regulation (Hanks & McIntosh, 1973). Our analysis implies that in the KNP density dependence of population growth rate only begins to operate at densities greater than 0.37 elephants/km2 In terms of the total park it is of interest to note that such a density was only achieved in 1968. Since then densities have been maintained at values ranging from 0.31 to 0.40 elephants/km2 .

Van Jaarsveld, Nicholls & Knight (1999) found no evidence for density dependent effects in South African elephant populations, with a mean density of 0.33 elephants/km2 (Hall-Martin, 1992).

Such a conclusion matches ours. The suggestion by Smuts (1975) that a density of 0.4 lephants/km2 still had no regulatory effect on reproduction does not agree with the results of our analyses, since the inhibition in population change conceivably results from differences between birth and death rates. However, our analyses were conducted on the sub-population level and changes in population size for a given region may have resulted from intrapopulation movements rather than changes in demographic variables.

Our value of 0.37 elephants/km2 as the density at which population growth rate is depressed is very much lower than the value of 0.57 proposed by Fowler & Smith (1973) as an ‘equilibrium’ density for the African elephant. It also differs considerably from the value of 1.19/km2 suggested by Armbruster & Lande (1993) as an equilibrium value for elephants in semi-arid regions.

These higher values however are very similar to the equilibrium density estimated by Laws (1969) for Tsavo in East Africa. The discrepancy between our value and those mentioned above may be due to differences in habitat quality or due to the effect of long term management (culling) of numbers on our analysis.

In summary, comparisons of studies elsewhere do not sensibly inform management within the KNP. There may be differences of opinion about what is a reasonable density, but it seems more likely that there are real, underlying differences in ecology. What this study shows is that densities in the KNP will tend to be regulated at around 0.37/km2.

What does this value mean? Habitat deterioration associated with densities slightly higher than the value of 0.37/km2 in the KNP is of concern and implies that the present conservation paradigm (maintenance of biological diversity) requires some management action when elephant densities exceed the value of 0.37.

Indeed, efforts to maintain the population substantially below this level – at 7000 to 7500 individuals – were based on Van Wyk & Fairall’s (1969) suggestion that densities of elephant >0.29 individuals/km2 may result in the destruction of vegetation.

Surveys have illustrated that widespread scarring of trees in the park by elephants only commenced during 1973 (Coetzee et al., 1979) when densities were at the level of expected density dependent feedback. Densities above 0.37 have occurred since 1995 in two sub-populations and habitat damage has been continuing ever since (pers. obs.). Thus, maintaining the population at a level where density dependent effects are apparent may cause habitat destruction.

Are culls necessary?

When densities exceed 0.37 they typically decline the following year when not culled. Thus, the strategy of culling immediately after high densities is premature. Wait a year and the populations will often decline without such controversial intervention. Moreover, the effectiveness of culls is often spurious. The immediate response of sub-populations of elephants to the cull was that of a local decrease in numbers, followed by a dramatic increase in population growth rate.

The rates of increase recorded in response to culling are often exceeded the maximum rate of increase of 7% estimated by Calef (1988) for the species. This implies that the calculated response of sub-populations to culling results not from an immediate increase in birth rate or a decrease in calving intervals, but rather from inter sub-population immigration, either by ‘vacancies’ created through the culling of sub-populations being occupied by members of neighbouring sub-populations, or by culling pressures inducing movements across subpopulation boundaries. Thus, culling of a given sub-population may reduce environmental pressures exerted on neighbouring areas, while increasing that on the areas occupied by the culled sub-population. This idea requires further investigation, especially in terms of the consequences such fluctuations in the disturbances brought about by elephant may have for local diversity.

Can culls be eliminated entirely? Even though our analyses show that at densities >0.37 elephants/km2 the killing of elephants may often be unnecessary, high densities have persisted for several years on occasion. We do not know if the vegetation of the KNP can withstand such high densities. With densities presently exceeding the cut-off values calculated for both the south and the northern management regions (see Table 2), vegetation changes there need to be monitored.

In summary, our management recommendations are simple. Culls should be considered only if a high elephant density persists for two consecutive years. They should not be an immediate response to high densities because typically such densities decline without intervention. The effects of persistent high densities on vegetation must be measured.

Acknowledgements

The Foundation for Research Development provided financial support and the study was sanctioned by the South African National Parks. The preparation of the typescript benefitted from discussions with Dr Theo Wassenaar and the comments from two anonymous referees. We would like to thank Mrs Colleen Wood and Mr Obert Mathebula who assisted with fieldwork and the maintenance of the data used on the present analyses. Messrs Hugo van Niekerk and Piet Otto were responsible for flying operations during the annual censuses. Messrs Eric Wood, Manie Coetzee and Marius Slippers helped with the collection of study material and we would like also to thank various members of the Department of Wildlife Management who assisted as observers during the annual censuses.

REFERENCES

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I participate because I care - CUSTOS NATURAE
No to Hotels in and commercialization of our National Parks.
No to Legalized Rhino and Lion trade.
Done 159 visits to National Parks.
What a wonderful privilege.


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