X-B8, 2012
THE ROLE OF REMOTE SENSING FOR SUSTAINABLE ELEPHANT MANAGEMENT
IN SOUTH AFRICA. FOUR MEDIUM SIZED GAME RESERVES AS CASE STUDIES.
M. Jordaan “
*Dept. of Environmental Sciences, University of South Africa, Johannesburg, South Africa - jordam@unisa.ac.za
KEY WORDS: Ecosystem, Change Detection, Management, Monitoring, Multispectral, Classification
ABSTRACT:
Loxodonta africana (African Elephant) are running out of living space so the protection of what space they have is essential.
Existing areas of suitable elephant habitat need to be protected not only from human development but from the elephants themselves.
As most elephant populations in South Africa are enclosed and multiplying, there is some increasing cause for concern as the damage
caused will escalate and could reach unsustainable proportions. This study examined the utilization of satellite images for the
detection of elephant induced ecosystem modification. A pilot study was conducted on four medium sized Game Reserves (each +30
000 ha) in South Africa. The aim was to ascertain the feasibility of using image analysis as instrument by which Game Reserve
managers could assess biodiversity richness, habitat loss, and population-habitat viability.
NDVI as indicator of primary production in vegetation is one of the instruments used to evaluate whether the carrying capacity for
elephants of each Game Reserve has been reached and to compare the current biomass with those of previous years. The study also
looked at the use of the woody canopy cover as target for change detection analysis.
Spectral characteristics of specific trees species which are known for being preferred by elephants were used to conduct a temporal
analysis on satellite images starting from the period when the elephants were re-introduced into each Game Reserve, thus attempting
to identify possible impact on the biodiversity of the respective Game Reserves. Images from satellites such as Landsat, SPOT,
Quickbird and SumbandilaSAT provided the needed data and maps.
1. INTRODUCTION
11. The Elephant Issue
The once abundant, free roaming, African elephant (Loxodonta
africana) has dwindled to a mere fraction of their once prolific
numbers. Less than 700 000 elephants are estimated to be left
in Africa (Blanc, Barnes, Craig, Dublin, Thouless, Douglas-
Hamilton, 2007). This has resulted in the African elephant
being listed as Cites Appendix 1 throughout most of Africa (In
Southern Africa elephants have been reclassified as an
Appendix 2 species)
Growing human populations and increasing human-elephant
conflict has forced stakeholders to cluster the remaining
elephants into relatively small areas (compared to their once
unlimited space) Yough & Van Aarde (2011). In South Africa
these *Reserves' are protected by means of electrified fencing,
preventing the elephants from roaming freely. Within these
boundaries they are cut off from their traditional seasonal
migration routes, essential natural resources as well as from
other elephant populations.
A drawback of the very successful conservation efforts in South
Africa is that the elephant numbers in these confined Reserves
are indeed increasing at an alarming rate ( Mackey, Page, Duffy
& Slotow, 2005) and have exceeded the outdated 'carrying
capacity’ of the larger reserves such as the Kruger National Park
(KNP). These growing numbers have instigated remedial action
from the KNP managers with processes such as culling and
translocation to other reserves (Blanc er al, 2007). These
methods were (and still remains) unpalatable to the larger
Society and new actions were required. The Minister of
Environment Affairs and Tourism (DEAT, 2008) has
promulgated new norms and standards for elephant
Management in South Africa. This forced all owners or
custodians of elephant to develop and implement an “Elephant
Management Plan” (XXX). This was applicable to all national,
provincial and private reserves and parks.
During the 1960’s and 70’s elephants could only found in four
areas in South Africa namely: Kruger National Park (+6000
elephants), Addo Elephant Park (+ 120 elephants), Knysna
Forest (+ 25 elephants) and northern KwaZulu/Natal (2200-300
elephants) (Blanc ef al, 2007). The last named two areas were
the only places where the elephants were still free roaming but
due to human-elephant conflict their number were decreasing
rapidly.
1.2 Population-habitat viability
“In short, the African elephant is a most attractive species, a
‘flagship’ animal, representing the widespread savannas and
woodlands of Africa” (Mundy, 2006, p588). The
overpopulation of elephants in Kruger National Park was at first
mitigated by re-locating entire elephant herds to smaller
reserves and parks. This included public reserves such as
Marakele, Pilansberg, and Mapungubwe as well as private
conservation areas such as Welgevonden, Phinda and Thanda.
The Management of the medium and small sized reserves were
keen to re-locate the KNP elephants due to their popularity as
tourist draw cards and to increase tourism revenue.
1.2.1 Elephant characteristics and demographics
The elephant is a ‘megaherbivore’ and is the world’s largest
land-living mammal, with mature bulls weighing in at six
tonnes and a height of more than 3.5 meters. In addition, it has
lifespan estimated at 60-65 years (Owen-Smith, 1988). Many
ecologists consider them to be a ‘keystone’ species, one which
is essential to maintaining an ecosystem. (Mundy, 2006)
