Annual Report 2008
International Elephant Foundation
(January 2008 – December 2008)
Between 23 -28 October 2007, eight elephants were collared in the western Hoanib
River (2 elephants), Hobatere Game Reserve (4 elephants) and Omusati regions (2
elephants) with GPS collars provided by Data Scout (SA). Three other elephants
were de-collared (these elephants had been collared in previous collaring exercises).
As of April 2008 all of the new collars had failed. This was because of either the
removal of the collars by the elephants or the failure of the collars due to a poor batch
of batteries having been provided by the manufacturer to Data Scout. Data Scout has
undertaken to provide an additional 8 collars to the project free of charge to
compensate for the lack of durability in the current collars. They have also
undertaken to part-fund the next collaring to reduce the cost to the Namibian Elephant
and Giraffe Trust (NEGT).
Behavioural studies have continued and the heavy rainfall during the 2008 wet season
has resulted in a change in feeding behaviour from mostly browsing during “normal”
years to mostly grazing during the current year. It is too early to tell whether the
increase in the abundance of vegetation will have any effect on the elephants’
2. GENERAL INFORMATION
(A) PROJECT TITLE: Home Range, Movement And Monitoring Of Elephants In
The Kunene And Omusati Regions Of Namibia.
(B) SUMMARY LINE: The project investigates the seasonal movement, seasonal
distribution, behaviour, genetics and social interactions of the elephants in the
Kunene and Omusati Regions of Namibia.
(C) PROJECT LEADER: Dr. Keith Leggett (elephant researcher)
(D) OTHER STAFF: Mr. Mike Godfrey, Ms. Elizabeth Weir
(E) COLLABORATORS AND OTHER INSTITUTIONAL AFFILIATIONS:
COLLABORATORS: Dr. Julian Fennessy
Ms. Claudia Heinze
Dr. Ursula Bechert (University of Oregon)
Dr. Rob Ramey (Independent Researcher)
Dr. Laura Brown (Independent Researcher)
Dr. Yirmed Dimeke (Ethiopian Elephant
Dr. Iain Douglas-Hamilton (Save the Elephant,
INSTITUTIONAL AFFILIATIONS: Earthwatch Institute
University of Sydney
Save the Elephants
Wilderness Wildlife Trust
International Elephant Foundation
Wildlife Conservation Society
(F) ACTIVITIES/PROGRESS IN THE LAST 12 MONTHS:
• 9 field trips
• Attended 1 community meeting
• Attended 2 meetings with Ministry of Environment and Tourism (MET)
on elephant related issues
• 5 expeditions with Earthwatch Institute volunteers
• Involvement of community game guards in various aspects of the research,
• Assistance to other researchers (Dr. Rob Ramey, Dr. Laura Brown, Dr.
(G) EXPLORATORY ACTIVITIES:
• Possible testosterone and oestrogen studies with Dr. Ursula Bechert
(University of Oregon) on elephants.
• Genetic research on the elephant populations in conjunction with Dr. Rob
Ramey and Dr. Laura Brown (Independent Researchers, Denver, USA) has
commenced and preliminary results are available.
• The NEGT has recently been approached by the MET to undertake
research on “problem elephants” within the research area. Funding is
currently being sourced for this project.
(H) PROBLEMS AND CONSTRAINTS:
• The vehicles used by the project are old and require constant and
• The 2008 wet season was the best wet season on record for almost 70
years with substantial rainfall across the research area. The long-term
average rainfall in the research area is 50-100mm. This year
approximately 350mm fell across the region. This severely restricted
research activities for 4 months because of the difficulty in accessing the
3. CURRENT PROJECT STATUS
ACTIVITIES AND ACHIEVEMENT OF OBJECTIVES:
3.1. Quantify the movements, range and seasonal distribution of elephants in
the Kunene and Omusati/northwestern Etosha areas of Namibia.
(1) Does the seasonal and home range of male elephant vary annually?
(2) How large is the home range of male desert-dwelling elephants?
(3) Is there a genetic bottleneck with regards to the desert-dwelling elephants?
In October 2007, eight elephants were GPS collared in the western Hoanib River, the
Hobatere Game Reserve and the western Omusati Region. This collaring was paid for
by USFWS, the International Elephant Foundation and private donors. The GPS
collars used were produced by Data Scout (SA). Two of the collars were either
removed by the elephants (WOM-6) or failed for unknown reasons (EKM-09) very
shortly after the collaring. With the exception of the elephants in the western Hoanib
River, the GPS collared elephants’ movements during the hot dry season were
restricted to areas around the permanent water sources. The range of all eastern
Hoanib River GPS collared elephants was further restricted to areas either
immediately around or inside Hobatere Game Reserve and Kaross Game Park. The
elephants in the Omustati region had a range restricted to areas around the permanent
The movements of the GPS collared elephants until the expiry of the collars are
described in detail in the following section. The home range of the elephants was
determined by minimum convex polygon (MCP) analysis. It is recognised that this is
not the best way to determine the home range but, while Kernel Analysis would have
probably been a more useful tool, the data were so limited in many cases as to make
this type of analysis ineffective.
The geopolitical and infrastructural developments in the Kunene and Omusati
Regions are presented in Figure 1.
4.1. Eastern Kunene Elephants
Eastern Kunene Male (EKM) -07
This is the first time that this elephant has been collared. EKM-07 is a mature male.
After collaring, EKM-07 spent his time in and around the southern border of Hobatere
Game Reserve. His daily movement and home range during the hot dry season were
relatively small (see Table 1 for details). This compressed home range during the hot
dry season around known water points and safe from disturbance is typical of
elephants in this area.
Eastern Kunene Male (EKM) -08
Until his collar failed in late November, EKM-08 spent his hot dry season in and
around Hobatere Game Reserve. His home range and daily movements were
relatively small (see Table 1 for details). Unfortunately, his collar failed before any
wet season data could be obtained.
Eastern Kunene Male (EKM) -09
This was the first time that this elephant has been collared. Unfortunately, EKM-09’s
collar failed soon after fitting, so very few data points were obtained for this elephant.
Eastern Kunene Male (EKM) -10
This is the first time that this elephant has been collared. EKM-10 remained within
the borders of Hobatere Game Reserve during the 2007 hot dry season. Only erratic
readings were recorded from EKM-10’s collar during the 2008 wet season. However,
they placed this elephant in the areas to the west of Hobatere Game Reserve. As very
little data were obtained from this collar it was difficult to draw any conclusions. The
home range data for EKM-10 during the hot dry and wet seasons are shown in Table
4.2. Western Kunene Elephants
Western Kunene Male (WKM) – 10
WKM-10 was collared for the fourth time. He still has the largest home range of any
of the collared elephants in northern Namibia and one of the largest home ranges ever
recorded for African elephants. WKM-10 spent the hot dry season in the Hoanib
River. He moved to the eastern section of the research area in early February 2008.
He stayed in this area until early March 2008 before moving briefly further east into
Etosha National Park. Unfortunately, his collar failed at this time. He was observed
to have returned to the western Hoanib River early in August 2008. His daily
movements and home ranges during the hot dry and wet seasons are shown in Table
Western Kunene Male (WKM) – 20
WKM-20 was a young male and this is the first time that this elephant has been
collared. Shortly after collaring, WKM-20 moved to the south of the Hoanib River
and spent his time there. In February 2008, WKM-20 moved from the hills in the
south of the Hoanib River catchment to the east, joining WKM-10 in the area to the
east of Hobatere Game Reserve. He remained here until early April 2008, when his
collar failed. He was observed to have returned to the western Hoanib River in
October 2008. His daily movements and home range during the hot dry and wet
seasons are shown in Table 1.
4.3. Western Omusati Elephants
Western Omusati Male (WOM) – 05
This is the first time that this elephant has been collared. WOM-05 stayed in the area
where he was collared for the entire hot dry season, with small daily movements and
home range. During the wet season, before WOM-05’s collar failed, he spent his time
in the areas north of where he was collared. His range was larger than during the hot
dry season, but still quite restricted. Details of his home range and daily movements
during both the hot dry and wet seasons are shown in Table 1.
Western Omusati Male (WOM) – 06
This is the first time that this elephant has been collared. Unfortunately, WOM-6
broke his collar within a month of its being fitted. His daily movements and home
range were fairly large before the collared failed (see Table 1 for details).
Table 1: Movement and home range data for GPS collared elephants during the
hot dry season 2007 and the wet season 2008.
N.a. – not analysed due to failure of the collars
The variance on average daily movement is high. This is due to several factors, not
least is of which is that, due to the erratic nature of the collars, none of the data sets
are complete. In addition, on the basis of hourly movement data obtained for
elephants in north-western Namibia in the past, it appears that elephants walk
excessively one day then spend the next few days resting (each individual has his own
pattern), leading to large differences in daily distances walked. This data has been
submitted for publication and copy of the paper will be supplied in later reports.
These hot dry and wet season data (where obtained) compare favourably to previously
gathered data on GPS collared elephants in northwest Namibia (see Table 2 for details
on previously collared elephants). Table 2 also shows the age, sex, number of data
points, period of study and home range (determined by MCP analysis) of GPS
collared elephants in the Kunene and Omusati Regions of northwest Namibia.
Table 2: Summary of current and previously GPS collared elephants in northwest Namibia .
4.4. Behavioural Studies
4.4.1. Carry out identification, social and behavioural studies on resident elephants.
The annual variations in water availability and ambient temperatures are significant in
an arid area (Jacobson et al., 1995; Leggett et al., 2001). This study examines the
behaviour of elephants in response to variations in environmental conditions. By
definition this study needs to be undertaken over a longer time scale to encompass the
wider variation in climatic conditions that occurs in an arid region.
Elephants were individually identified using a combination of photographs and
identification sheets. The photographic techniques used were similar to techniques
already described by Douglas-Hamilton and Douglas-Hamilton (1975), Moss (1982)
and Sukumar (1989). Photographs were taken from the front, left and right side of
each individual. In addition, field identification sheets were kept for each individual
elephant. When an unknown elephant was characterised, it was given a unique
nomenclature and, during all subsequent observations, its nomenclature, current
elephant-elephant associations and activity were recorded. The exception to this was
if an elephant broke a tusk or if any additional holes or tears in the ears were noted.
In this event, the relevant identification sheets were updated and the changes added to
Three different types of activity studies were undertaken and compared. All methods
used either point sample techniques or focal sample techniques over specified time
intervals. When studying elephant groups, a point sample technique similar to that
described by Barnes (1982) and Kalemera (1987) was used. All individual activity
within the group was recorded at 2-minute intervals for up to 3 hours. This 2-minute
scan study obtained data only on feeding, water, resting, social and walking activities
for multiple individuals. The second method used a focal sample technique, where
known individuals were observed for a minimum of 30 minutes to a maximum of 3
hours, data being recorded at 5-minute intervals (Kabigumila, 1993; Lee, 1996).
Detailed information on each individual was recorded on a check sheet similar to that
described by Lee (1996), and activities were defined in a manner similar to that
described by Guy (1976). These were categorised under 5 main headings and
subdivided as follows:
(c) Debarking of trees
(2) Activities associated with water:
(a) Drinking (Water Activities)
(c) Dust bathing
(a) Standing or sleeping in shade
(b) Standing or sleeping in the open or sun
(4) Social activities:
Activities include: playing, fighting, communication, aggression, nursing and courtship
The third method also employed a focal sample technique similar to that described by
Guy (1976). The technique focused on an individual, with data recorded continuously
for between 60 minutes and 5 hours, using the same activity categories as described
for the 5-minute focal animal study. A change in behaviour was defined as any
activity undertaken for longer than 1 minute. For example, if an elephant was
walking and stopped to feed for less than a minute, then walked on, the activity would
be regarded as “walking” and not “walking/feeding”.
Throughout the study, an effort was made to collect data on all age groups. For the
purposes of this study, age groups were defined as follows: juveniles, being those
young elephants that had not yet been weaned (0-5 years), sub-adults (5-10 years
female, or until they have their own offspring, 5-14 years male, or until they leave the
family unit), and adults (>10 years female; >14 years male). During each field trip,
attempts were made to collect data on all age groups for every hour between 0700 and
1900. However, due to seasonal light availability, this was not possible in all morning
and evening time slots.
The first elephant encountered by the researcher at the start of a research day was
observed and activities recorded. To avoid biasing the study to those individuals that
were easily found, if the first individual encountered had been observed in the
previous day, observations were not undertaken and another elephant was sought
instead. Most elephants were initially encountered either in the riverbeds or on the
river plains, then followed and observed. Although this infers a bias towards
individuals that reside or traverse these areas, elephants in this area spend about 85%
of their time in these habitats. When undertaking 2-minute scan or 5-minute focal
animal studies, it was possible to observe up to four different individuals or groups in
a day, depending on accessibility. However, the number of studies that could be
undertaken was reduced when longer-term studies were conducted. There was
generally a lack of data collected during the wet season as it was difficult to get into
the field during this period due to rainfall and flooding in the rivers.
Identification and social studies are ongoing. As calves are born or any new elephants
appear in the research area, they are identified, photographed and catalogued.
Seasonal activity budget studies are currently in process and only preliminary analysis
has been conducted. These studies also included behavioural and social interactions
as well as current herd associations. Results from the 2008 season are presented in
Table 3: Summary of diurnal activity (as percentage of time) from data obtained during the 2008 research season
As can be seen from the results, observed activity during the 2008 season has varied
significantly from previous years. During the 2008 wet season, approximately
350mm of rain was recorded at Sesfontein (long-term average – 87.9mm) and
approximately the same amount was recorded in Purros (no annual average available,
but the town is in the 50mm isohyet). This was reflected in the amount of available
grazing and browsing, which was much greater than in previous years. Grazing was
by the far the dominant feeding activity during the later part of the wet season
whereas, in all previous years, browsing has been the dominant feeding activity.
4.4.2 The Dung Study
From data obtained during the activity studies it became apparent that elephants in the
arid area of western Namibia defecated less than any other group of elephants in
Africa (Table 4). A detailed series of studies examining the frequency, seed
composition and potential distribution, weight and the percentage of moisture in the
dung was undertaken.
Table 4: Comparison between defecation rates of elephants in three African countries
When a known individual was observed to defecate, the time, number of boluses and
the total weight (using a digital 5000g scale) of the defecation event were recorded.
In addition, one bolus was retained from each defecation event to determine the
percentage of moisture in the bolus. This study was undertaken to determine whether
the percentage of moisture in the dung of desert-dwelling elephants varied
significantly from elephants in higher rainfall areas of Africa. The bolus was weighed
when first collected (within 15 minutes and 2 hours of the defecation event,
depending on accessibility) and then stored in a net bag to allow airflow and prevent
seed germination. The weight was then recorded at 24, 48 and 72 hour, and one month
intervals. In practice, measurements were taken at 24 hour intervals and the bolus then
left to air dry in the atmosphere for one month when it was re-weighed.
A second bolus was retained from each defecation event for seed analysis. This study
was undertaken to look at the dispersal of Acacia erioloba and Faidherbia albida
seeds in the dung. Once a bolus had been collected, it was dissected and the seeds
were extracted and washed. Only whole seeds were then used for further analysis;
partially crushed seeds and seeds that contained weevil holes were discarded on the
grounds that they would never germinate. All seeds found in the dung were taken to
the National Herbarium in Windhoek for identification. The vast majority (99%) of
seeds found in the dung were either A. erioloba or F. albida seeds.
As the seeds in an elephant’s stomach absorb moisture and swell to as much as twice
their normal size, in order to establish the correct weight of the seeds at the time of
consumption, dry seeds collected from A. erioloba pods were weighed. 1000 seeds
were weighed 3 times and divided to get the mean weight of one seed, which was
determined to be 0.26g. A similar exercise was undertaken with F. albida and the
seed weight was determined to be 0.25g.
A summary of results obtained for the last three years of the project are shown in
Table 3: Summary of dung results 2004-2008.
In 2008, defecations consisted of an average of 4.73 boluses, which was higher than
the average observed during the years 2004-2007. The average weight of one bolus
(usually recorded after 15 minutes – 2 hours of defecation) was 1322 g and the
average total defecation was 6257 g. This undoubtedly reflects the availability
vegetation that was observed during this year.
Only two seed species (Acacia. erioloba and Faidherbia albida) were observed in the
dung. There were a large number of seeds observed in the dung during the wet and
early cold dry seasons, but, as the hot dry season developed, there was a noticeable
decline in the number of A. erioloba and an increase in the F. Albida seeds. The
average number of seeds found in each bolus was 120 (0 – 230), which was lower
than the average number of seeds found n previous years. This was probably due to
the lower rainfall of the 2006-2007 wet season rather than the higher rainfall observed
during 2007-2008 wet season.
The 2008 dung analysis revealed that an average of 16.8% of moisture in the elephant
dung was lost in the initial 24 hours after collection, which was similar to that
recorded in previous years. However, the moisture then decreased by a further 11.8%
over the next 24-hour period (this was exceptionally high in comparison to previous
years). There was a further 42.3% reduction to a dry weight measured after one
4.5. Document the demographic structure of elephant herds, including herd
sizes, recruitment rates, age/sex ratios and mortality factors in the
western Kunene, eastern Kunene, and Omusati Regions.
The desert-dwelling elephant’s reproductive rate is probably one of the lowest of any
elephant population. This study was undertaken to assess birth rates, mortality and
the ratio of males to females in the elephant population of northwest Namibia.
The family units and free roaming males of the research area were studied by direct
observation and data recorded over the 10 years of study.
The reproduction rate of the desert-dwelling elephants varies considerably and is
dependent on environmental conditions. Viljoen (1988) determined that the
reproduction rate of elephants in the arid western areas of Namibia was 1.9%, while in
the eastern section of the research area, it was 2.8%. Viljoen’s study was conducted
in 1981-83, a period of high stress for the elephants. Not only was there a civil war
but there was also an arid climatic cycle that was affecting elephants’ behaviour.
During the NEGT study period, 14 calves have been born (reproduction rate of
~2.5%) in the arid western areas. These reproduction rates are low compared to those
in elephant populations in higher rainfall areas of Namibia, with reproduction rates of
up to 3.3% in the eastern section of the research area (Leggett, unpublished) and
Etosha National Park (Lindeque, 1991). The reason for the low reproduction rates in
the western region is probably due to the effect of the arid environment and the lack
of nutritious vegetation on the females’ ability to conceive.
Data on herd structure and demographics has been continually collected during the
research. The current age class distributions are shown schematically in Figures 9 and
Figure 10: Age class distribution of male desert-dwelling elephants
Figure 11: Age class distribution of female desert-dwelling elephants
Age class definitions (after Moss 1996):
0A 0-4.9 years
0B 5-9.9 years
1A 10-14.9 years
1B 15-19.9 years
2 20-24.9 years
3 25-34.9 years
4 35-49.9 years
The data reflect the history of these elephants with few adult males above 35 years as
these would have been killed during the poaching events of the late 1970s and early
1980s. by contrast there are a large percentage of female elephants in this age class.
There are currently few male and female elephants in the 1B, 2 and 3 age groups and
the reason for this is uncertain. These years correspond to the late 1980’s and early
1990’s, while poaching had decreased during this period, there were several dry
season back to back, possibly reducing the breeding rate of these elephants. Since this
time the elephants have been reproducing at a rate of about 2.8%. The relative
abundance of young males is interesting and could point to preferential selection for
males under “normal” rainfall condition and periods of low stress.
2006/2007 was a relatively low rainfall year, with no rainfall recorded west of
Sesfontein. Interestingly, only 2 mortalities (one adult female (20-24 years of age)
and one juvenile (2 years of age) were recorded during the 2006/2007 drought period.
Neither of these two deaths could be directly attributed to the drought itself. The
adult female was shot by a local Ovahimba herdsman who claimed that the female
attacked him. This is possible as the female had a young calf (the other mortality) and
she may have been protecting the calf. The calf was still suckling at the time and
lasted only 3 more months in the care of her grandmother. Malnutrition was thought
to be responsible for the calf’s death. It is possible that the drought was not over a
significantly long enough period to affect mortality. The 2007/2008 wet season was
an above average rainfall year and no deaths were recorded during this year.
In the 10 years of the study, 4 calves (2 males and 2 females), 2 sub-adults (2 males),
and 4 adults (2 females and 2 males) have died. Of these, one adult female and one
sub-adult male were shot either on problem animal control or by local herdsmen.
4.6. Provide appropriate elephant data and training to the MET, conservancy
organisations and selected stakeholders to facilitate appropriate
monitoring, management plans and decision-making within known
Several meetings have been undertaken with MET officials both in Outjo and
Windhoek concerning elephants and elephant-related activities. One community
meeting was undertaken with members of the Sesfontein Conservancy. It has been
agreed to undertake a series of training seminars with local conservancy members.
The venue and timing of these training seminars has yet to be determined. After
several unsuccessful approaches to conservancies, an alternative way of training
conservancy game guides has been developed with the Namibian Academy for
Tourism and Hospitality (NATH). Two courses will be offered through NATH in
2009. Initially, the course will be offered to tour guides already employed by safari
companies; at a later time, conservancy game guides will be offered the same course.
The course will be made up of theoretical and practical courses in the following
Theoretical course (3 x 4 hour lectures)
(a) Origin and classification
(b) Anatomy and physiology
(e) Social structure
(f) Historical distribution and abundance
(g) Present day distribution and abundance in Namibia
Practical Course (4 days in the field)
(a) How to track elephants
(b) How to behave around elephants
(c) How to deal with aggressive elephants
(d) Individual characteristics and identification
(e) How to avoid elephant problems while camping
(f) How to get the most out of the elephant experience
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Douglas-Hamilton, I. and Douglas-Hamilton, O. 1975. Among the Elephants . Collins
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Guy, P.R. 1976. Diurnal activity patterns of elephants in the Sengwa Region,
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Jacobson, P.J., Jacobson, K.M., Seely, M.K. 1995. Ephemeral Rivers and Their
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Kabigumila, J. 1993. Diurnal activity of elephants in the Ngorongoro Crater,
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Kalemera, M.C. 1987. Dry season diurnal activity of elephants in Lake Manyara
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