Content uploaded by Lucy E. King
Author content
All content in this area was uploaded by Lucy E. King on Mar 09, 2023
Content may be subject to copyright.
91Pachyderm No. 63 July 2021—September 2022
The outcome of an elephant translocation from Isiolo to Tsavo
East National Park, Kenya
Lydia Tiller1,2*, Lucy King1,3, Fredrick Lala4, Frank Pope1, Chris Thouless1, Jake Wall5, Iain
Douglas-Hamilton1
1Save the Elephants, PO Box 54667, Nairobi 00200, Kenya
2Durrell Institute of Conservation and Ecology, University of Kent, Canterbury, UK
3Department of Zoology, University of Oxford, Oxford, UK
4Wildlife Research and Training Institute, PO Box 842, Naivasha 20117, Kenya
5Mara Elephant Project, PO Box 2606, Nairobi 00502, Kenya
*corresponding author: lydiatiller@gmail.com
Abstract
This management piece documents the outcome of an elephant translocation from Isiolo to Tsavo East
National Park, Kenya in November 2021. The translocation aimed to reduce human-elephant conict in the
area and to prevent any retaliation toward the elephants. This was achieved by removing the ‘problem elephant
group’, however the aim of resettling the elephants in Tsavo was not achieved, as the group fragmented and
some swiftly moved far outside the release site. Two elephants, which we were able to monitor through
satellite collars, exhibited homing behaviour and both left Tsavo East National Park within 1–7 weeks of
being released. If translocation continues to be the method of choice for problem elephants, there is a need
for thorough planning and sound science to inform future operations, which should include collaring of
each individual. Trained personnel and substantial budgeting for post release monitoring, and any potential
conict-reduction interventions, are therefore key management considerations for ensuring the health and
wellbeing of translocated elephants in the future. In the long-term, focusing mitigation management on a
larger number of habitual crop-raiders will have more impact and be a more eective approach for elephant
managers. This could involve better spatial land-use planning, maintenance of corridors between protected
areas, negative conditioning tactics and maintenance and upgrading of barriers.
Résumé
Ce document relatif à la gestion des éléphants rend compte du bilan de la translocation de plusieurs sujets
depuis Isiolo jusqu’au parc national de Tsavo Est au Kenya en novembre 2021. L’objectif était de réduire les
conits humains-éléphants dans la zone et d’éviter toute forme de représailles de la part des habitants. Les
« éléphants problématiques » ont donc été délocalisés, mais l’ambition initiale de les établir dans Tsavo Est
n’a pu être nalisée du fait de la fragmentation du groupe après la remise en liberté et de certains éléments
s’étant rapidement déplacés loin du site de lâcher. Deux sujets, que nous avons pu suivre grâce à leur collier
GPS, ont montré un comportement instinctif de retour vers leur habitat précédent et tous deux ont quitté le
parc national de Tsavo Est dans les sept semaines suivant leur introduction. Si la méthode de la translocation
continue d’être privilégiée pour les éléphants problématiques, il sera nécessaire de s’appuyer sur une
planication rigoureuse et des données scientiques solides pour les prochaines opérations, ainsi que sur la
mise en place de colliers émetteurs sur chacun des individus. Du personnel formé et un budget substantiel,
pour la post-introduction des animaux et les interventions potentielles de réduction des conits, sont donc
les clefs pour une gestion de qualité et pour assurer le bien-être et la bonne santé des éléphants transférés à
l’avenir. À long terme, il convient d’accentuer les interventions d’atténuation envers un plus grand nombre
92 Pachyderm No. 63 July 2021—September 2022
Tiller et al.
d’éléphants habitués à piller les cultures, an d’avoir un réel impact et une approche plus ecace pour
les personnes chargées de leur gestion. Cela peut se traduire par une meilleure planication de l’usage
des terres, l’entretien des couloirs biologiques entre les zones protégées, des tactiques de conditionnement
négatif et la maintenance ou l’amélioration des barrières.
Introduction
Translocation is a management tool involving
relocation of wild animals from one part of their
range to another. It is often used to re-establish or
boost a population that is considered too small.
Elephant translocations are also used to reduce
the population in small areas and to mitigate
human-elephant conict (HEC), when a small
number of individual elephants are responsible
for many conict incidents (IUCN 1998).
Translocations are challenging and often fail or
see limited success, documented in a number
of case studies from Asia and Africa (Fernando
et al. 2012; Pinter-Wollman 2009; Tiller et al.
2022). The success of translocating animals
depends on the ability of the individual to survive
by nding key resources, avoiding predation and
human settlement, and later on reproducing in an
unfamiliar environment (Berger-Tal et al. 2020).
In East Africa, elephant translocations are still
relatively rare compared to South Africa, where
the rst translocation was in the 1970’s and, since
then, has been fairly common practice because
of the large number of small, highly managed
populations (Dublin and Niskanen 2003).
The rst translocation in Kenya took place in
September 1995 when Kenya Wildlife Service
(KWS) moved 26 elephants during ve dierent
operations from Mwea National Reserve (NR) to
Tsavo East National Park (TENP), a largely unfenced
area. Since then, TENP has become the main release
site for other elephant translocations in Kenya (Table
1).
During the rst translocations in Kenya in 1995
and 1996, ve of the elephants died (three during
immobilisation and two a few days after release).
Monitoring of the remaining 21 elephants was not
undertaken and so the success of the operation post-
release remains unclear (Njumbi et al. 1996). Since
then, there have been at least 18 other elephant
translocation events in Kenya, with release sites of
seven being Tsavo East NP (Table 1). Most of these
translocations were a response to overpopulations of
elephants in certain areas and to HEC.
Within these translocation operations in Kenya,
there are several documented cases of mortality (Muir
2000; Pinter-Wollman et al. 2009; Tiller et al. 2022),
a continuation of ‘problem’ behaviours such as crop
raiding and fence breaking (Pinter-Wollman et al.
2009; Tiller et al. 2022) and ‘homing behaviour’,
where the elephants reject their release site and try to
return home to their home location or natal territory,
often moving through human dominated landscapes in
the process (Muir 2000; Pinter-Wollman et al. 2009).
This short paper documents the outcome of an
elephant translocation from Kithima in Isiolo County
Year From To Total Source
1995–1996 Mwea NR Tsavo East NP 16 Njumbi et al. 1996
1999 Mwaluganje Elephant Sanctuary Tsavo East NP 28 Muir 2000
2000 Shimba Hills NR Tsavo East NP 4 Litoroh et al. 2001
2005 himba Hills NR Tsavo East NP 150 Pinter-Wollman 2009
2006 Shimba Hills NR Tsavo East NP 76 KWS darting protocol
2006 Ngulia, rhino Valley Tsavo East NP 220 Okita 2008
2016 Chyulu Hills Tsavo East NP 1 Lala pers. comm. 2022
2018 Borana/Lewa/Solio conservancies Tsavo East NP 5Tiller et al .2022
Table 1. Elephant translocations in Kenya where the release site was in Tsavo East National Park (NP)
93Pachyderm No. 63 July 2021—September 2022
The outcome of an elephant translocation from Isiolo to Tsavo East National Park, Kenya
to Tsavo East NP on 26 November 2021. Two
elephants were tted with satellite collars and
were part of a group of seven elephants that
was designated for translocation. They had been
identied as ‘problem elephants’ by the KWS,
based on reported incidents of crop raiding, and
had been observed ‘roaming’ through human
settlements. The elephants were also reported
walking within the busy town of Isiolo. KWS
carried out several mitigation operations to
chase away the elephants from the community,
but to no avail as the elephants frequently
returned. Consequently, community members
were becoming angry about the situation and
threatened to poison the elephants. Thus, with
mounting tensions and the threats the elephants
posed to human livelihoods and life, the
decision was made to capture and translocate the
elephants to Tsavo East NP. The fate of the other
ve elephants (three that were translocated and
two that were not found before the translocation
operation) remains unknown.
Methods
Five of seven target elephants (three sub-adult
males, one male calf and one female adult) were
located, tranquilised from helicopters, loaded
into crates, and then transported separately by
road to TENP in a journey that took between
12 and 18 hours. Upon arrival in TENP, all ve
were released immediately on the 28 November
2022. All national protocols on capture and
animal handling were followed (KWS 2016).
The translocation was to be carried out in two
operations due to limited space in the transport
vehicles, but upon return for the second phase
of the operation the two remaining elephants
could not be found. Two of the sub-adult male
elephants, named Isiolo and Njoroge, were tted
with satellite collars (Savannah Tracking GL200
GPS). These collars consisted of a GPS unit, a
VHF transmitter beacon and a battery integrated
into one unit. The collars were tted by a team
including a veterinarian from the KWS. All the
tracking collars were set to acquire GPS xes at
1–hour intervals. Movement data were projected
on the Universal Transverse Mercator (UTM)
WGS-84 reference system.
Isiolo was observed twice during a collared
elephant aerial monitoring exercise undertaken by the
Tsavo Trust, where photos were taken and observations
recorded. However, Njoroge was not observed whilst
in TENP, as he left the park shortly after release.
Results
The sub-adult elephant Njoroge was hard-released near
Gazi on the eastern side of the Yatta Plateau, north of
the Galana river, in TENP. This area at the time had
adequate vegetation and is near two rivers, the Galana
and the Tiva. As soon as Njoroge was released, he
exhibited homing behaviour, as he started to travel
north-east through the park in the direction of Isiolo.
He was observed during this time without any other
members of his group or other individuals. Five days
after release, Njoroge had left TENP. He continued
to travel north crossing the Tiva river and three
roads, including a main tarmac road (Thika-Garissa
highway) before reaching Garissa, an area of historical
insecurity challenges. Unfortunately, Njoroge’s collar
stopped reporting on 5 February 2022 when he was
approximately 370 km from the release site, 31 km
from Kora NP, 38 km from Rahole NR and 100 km
from Meru NP (Figure 1). Several attempts have been
made to nd Njoroge and remove or replace his collar,
though have so far all have been unsuccessful.
The other sub-adult male, Isiolo, was released at the
same location as Njoroge, and from day one he also
exhibited homing behaviour, as he started to travel
north-west within TENP. He was observed during this
time without any of the members of the group with
whom he was translocated. However, his movements
north were prevented by an electric fence on the park
boundary. He then walked up and down the fence
repeatedly until, in early January, he set o south and
west of the Yatta Plateau, crossing the Tiva river.
On 7 January 2022, Isiolo left the park and entered
community farmland in the Ngiluni area. He was
initially unable to leave this area, as he could not cross
the two-strand electric fence that had been recently
erected between the community area and national
park. He walked along the fence line trying to nd
a way back into TENP (Figure 1). On 18 January
2022, there was an attempt by KWS, Tsavo Trust
and the Sheldrick Wildlife Trust to push Isiolo back
into the park using helicopters (Fig. 2). However, this
attempt was unsuccessful. Isiolo eventually made his
way into TENP by crossing back over the Tiva river.
94 Pachyderm No. 63 July 2021—September 2022
Tiller et al.
Figure 1. Movement tracks of the two translocated bull elephants, Isiolo and Njoroge, after translocation
from northern Kenya to the Tsavo East National Park. (© Maps drawn by Lydia Tiller)
95Pachyderm No. 63 July 2021—September 2022
The outcome of an elephant translocation from Isiolo to Tsavo East National Park, Kenya
Figure 2. Helicopter trying to push Isiolo back into Tsavo East National Park on 18 January
2022. This management intervention attempt was unsuccessful. (© Image courtesy of
Tsavo Trust)
He then stayed on the west of the Yatta Plateau
and travelled west. He spent time close to the
Standard Gauge Railway (SGR) and walked
up and down, presumably looking for a place
to cross. On 18 April 2022 at around 11pm, he
crossed under the SGR railway using one of the
wildlife underpasses (called Kanga corridor) and
also crossed the tarmac of the busy Mombasa
highway. He then entered and traversed Tsavo
West NP, travelling west before he left the Tsavo
West NP on 24 April 2022. He then spent time
in the Rombo community grazing area, close to
the Tsavo river. He then travelled north again
to Mbirikani community area where he stayed
in grazing areas, and at times walked close to
agricultural land. Here, he was approximately 138
km west from his translocation drop-o location.
Discussion
This short paper describes the elephant
translocation operation from Isiolo to TENP in
Kenya and documents the interesting behaviour
displayed by the two translocated elephants,
who were collared. The translocation aimed to
prevent the local community from taking retaliatory
action toward ‘problem elephants’ and to reduce HEC,
which was achieved in terms of removing this elephant
group. However, the objectives of the mission in terms
of the group settling in the designated area was not
achieved. The elephant group separated and two
elephants, which we were able to monitor through the
satellite collars, exhibited homing behaviour and both
left TENP within 1–7 weeks of being released. The
elephant Njoroge is now many kilometres away from
his release site, probably getting closer to his original
home territory, but is unable to be monitored due to
the collar failing. Isiolo also left the park and spent
time in the community ranching area of the Amboseli
ecosystem. The fate of the other ve elephants (three
that were translocated and two that were not found
before the translocation operation) is unknown.
TENP has been the release site for a majority of the
translocations in Kenya, as it constitutes part of the
largest conservation area in Kenya, and until recently
was considered underpopulated by elephants (Table
1). However, the suitability of this site for future
translocations should be reconsidered, due to the
homing behaviour documented in this case study and
others (Muir 2000; Pinter-Wollman et al. 2009), high
96 Pachyderm No. 63 July 2021—September 2022
Tiller et al.
mortality rates (Muir 2000; Pinter-Wollman et
al. 2009; Tiller et al. 2022) and the continuation
of problem behaviours, such as crop raiding and
fence breaking (Pinter-Wollman et al. 2009; Tiller
et al. 2022). Additionally, much of TENP to the
north and east is unfenced, meaning elephants are
able to walk back towards their original range,
but often having to traverse community and
agricultural areas.
Homing behaviour, seen in these two
elephants, has also been documented in other
elephant translocations in Kenya (Pinter-
Wollman 2009); South Africa (Garai and Car
2001; Viljoen et al. 2015), Sri Lanka (Fernando
et al. 2012) and India (Lahiri-Choudhury 1993).
In a translocation of 150 elephants from the
Shimba Hills NR to TENP, 11 of the elephants
left TENP and either returned back to the Shimba
Hills or went to other sites (Pinter-Wollman et al.
2009). The elephants Isiolo and Njoroge showed
homing behaviours as it appeared they “collected
their thoughts” and then set out in a direction
that led towards home. When Isiolo encountered
physical barriers (electric fence) he made two
attempts to cross, and then seemed to give up
and embark on an exploratory course that took
him to new areas. This has been observed with
an elephant named Lugard who was captured
in an area named Hunter’s Lodge in Kenya and
translocated to Lugaard’s Falls in TENP. He rst
moved quickly back towards Hunter’s Lodge, but
after entering dense settlement, he gave up and
went on a circuitous route south of the Chyulu
Hills and eventually habituated to that area and
switched from mainly nocturnal movements
to mainly diurnal (Dr. Iain Douglas-Hamilton
2022, pers. Comm.). In Njoroge’s case, he broke
free quite quickly after translocation and made
an epic journey of over 370 kilometres towards
his original homeland. The longest previously
documented homing distance achieved by an
elephant was approximately 300 km following
translocation in South Africa (Viljoen et al.
2015).
Fortunately, the two elephants in this report
survived the rst few months after translocation,
although we are now only able to monitor one of
them. In other elephant translocations to TENP,
success rates have been low due to mortality;
for example, in 1999, 30 bull elephants were
translocated from Mwalugange Elephant Sanctuary
(MES) in the Shimba Hills to TENP. Of these
elephants, two died from shock and internal injuries
during the translocation itself, and one elephant died
after leaving the park and walking to a place called
Kili in coast province, where he got stuck in the
mud. The fate of the other elephants is unknown, as
only four the elephants were spotted in TENP after
the translocation (Muir 2000). Another example of
mortality occurring during translocation is of the 150
elephants translocated from the Shimba Hills NR to
TENP in 2005. While the operation was considered
successful at mitigating HEC in the Shimba Hills
vicinity, of the 109 translocated elephants with a
known fate over two months, 85 elephants survived
while 24 elephants died. This was due to a variety of
reasons: one was killed by poaching; two were shot
by the KWS; six died during transit; three died from
unknown causes; and 12 calves went missing and
presumably died. The study also found that, following
translocation, bulls and calves were more likely to
die than females (Pinter-Wollman et al. 2009). In
a 2018 translocation of ve elephants from Lewa
Conservancy to TENP, three of these elephants were
killed (two were poached and one died due to conict).
Two of the elephants were killed within four months
after being translocated, and the third elephant within
a year (Tiller et al. 2022).
Translocation of problem male elephants is
unlikely to be the most eective and humane method
to mitigate conict between people and elephants
(Boast et al. 2016; Massei et al. 2010). Translocating
problem elephants may simply shift the problem
elsewhere (Fernando et al. 2012). In a number of
studies, there has been a reported continuation of
problem behaviours such as crop raiding and fence
breaking in the new area in which the elephants have
been released. For example, in Sri Lanka, Fernando et
al. (2012) studied tracking data from 12 male Asian
elephants, who were classied as ‘problem animals’.
These elephants were captured in community areas
and translocated into national parks. All 12 elephants
left the protected areas and became involved in
incidents of HEC (fence breaking and crop raiding).
In a 2018 translocation from Lewa Conservancy to
TENP one of the elephants broke out of an electric
fence eight months after being released and spent
2% of his time in farmland, most likely crop raiding
(Tiller et al. 2022). Crop raiding behaviour can be a
trait found in a high percentage of individuals of both
97Pachyderm No. 63 July 2021—September 2022
The outcome of an elephant translocation from Isiolo to Tsavo East National Park, Kenya
sexes in a population. Thus, removing a few
habitual raiders will not necessarily solve the
problem at the source (Hahn et al. 2022). It is also
documented that crop raiding behaviour can be
passed down to younger elephants through social
learning (Chiyo et al. 2011; 2012; Evans 2015).
When translocating elephants, we must also
consider the welfare of the animals. Translocation
is likely to cause a high level of stress, including
the trauma of the translocation experience itself
and of being left alone in a new ecosystem with
unfamiliar elephants and resources (Pinter-
Wollman et al. 2009). However, a soft release,
where elephants are held in a large enclosure
for some time prior to release, may be a way
of reducing post-translocation stress and may
prevent elephants from breaking electric fences
(Dublin and Niskanen 2003; Garai and Carr
2001).
Conclusion
HEC continues to increase across much of the
African savannah elephant range, as the rapid
conversion of elephant habitat into agriculture
puts people on the frontline of conict with
wildlife. There is mounting political pressure
to address this conict, as tensions are rising in
communities impacted by the elephants that are
causing damage to crops or causing injury to, and
death of, people and livestock. Where large scale
fencing or installation of barriers is not feasible
or practical, translocation has often been used to
address these issues and show communities that
action is being taken. However, the relatively
low success rate of documented translocations
suggest that it is not necessarily the most eective
solution for problem elephants: nancial costs
are incurred, welfare concerns are created, and
problems may be translocated along with the
elephant. Focusing mitigation management on
a larger number of elephant habitual raiders
will have more impact in the long-term and be
a more eective management tactic for elephant
managers. This could involve better spatial land-
use planning, maintenance of corridors between
protected areas, negative conditioning tactics and
the maintenance and upgrading of barriers.
If translocation continues to be the method
of choice for problem elephants, there is a need for
thorough planning and sound science to inform future
operations, which should include collaring of each
individual. Trained personnel and a substantial budget
for post release monitoring, and any potential conict-
reduction interventions, are therefore key management
considerations for ensuring the health and wellbeing
of translocated elephants in the future.
Acknowledgments
Thanks to the Director General of Kenya Wildlife
Service who authorised this research, and who?
initiated this collaborative research. Special thanks
to Nick Haller at Tsavo Trust for conducting aerial
monitoring of the collared elephants and to Mara
Elephant Project and Space for Giants for providing
the collars in this translocation operation.
References
Berger-Tal O, Blumstein DT, Swaisgood RR. 2020.
Conservation translocations: a review of common
diculties and promising directions. Animal
Conservation 23: 121–131.
Chiyo PI, Archie EA, Hollister-Smith JA, Lee PC,
Poole JH, Moss CJ, Alberts SC. 2011. Association
patterns of African elephants in all-male groups: The
role of age and genetic relatedness. Animal Behaviour
81 (6): 1093–1099.
Chiyo PI, Moss CJ, Alberts SC. 2012. The inuence
of life history milestones and association networks on
crop-raiding behaviour in male African elephants.
PLoS One 7 (2): e31382.
Dublin HT and Niskanen LS. 2003. IUCN/SSC
AfESG Guidelines for the in situ translocation of the
African Elephant for conservation purposes. IUCN,
Gland, Switzerland and Cambridge, UK.
Fernando P, Leimgruber P, Prasad T, Pastorini J.
2012. Problem–elephant translocation: Translocating
the problem and the elephant? PLoS One 7 (12):
e50917.
Garai ME and Carr RD. 2001. Unsuccessful
introductions of adult elephant bulls to conned areas
in South Africa. Pachyderm 31: 52–57.
Hahn NR, Wall J, Denninger‐Snyder K, Goss
M, Sairowua W, Mbise N, Estes, AB, Ndambuki S,
Mjingo EE, Douglas‐Hamiliton I, Wittemyer G. 2022.
98 Pachyderm No. 63 July 2021—September 2022
Tiller et al.
Risk perception and tolerance shape variation
in agricultural use for a transboundary elephant
population. Journal of Animal Ecology 91 (1):
112–123.
IUCN. 1998. Guidelines for Re-introductions.
Prepared by the IUCN/SSC Re-introduction
Specialist Group. IUCN.
KWS. 2016. Kenya Wildlife Service (KWS)
Guidelines on Veterinary Practice. Nairobi,
Kenya.
Lahiri-Choudhury DK. 1993. Problems of
wild elephant translocation. Oryx 27 (1): 53–55.
Litoroh M, Omondi P, Bitok E, Wambwa E.
2001. Two successful elephant translocations in
Kenya. Pachyderm 31 (2): 74–75.
Massei G, Quy RJ, Gurney J, Cowan DP.
2010. Can translocations be used to mitigate
human–wildlife conicts? Wildlife Research 37
(5): 428–439.
Mijele D, Obanda V, Omondi P, Soriguer RC,
Gakuya F, Otiende M, Hongo P, Alasaad S. 2013.
Spatio-temporal distribution of injured elephants
in Masai Mara and the putative negative and
positive roles of the local community. PLoS One
8(7): p.e71179.
Muir C. 2000. Monitoring the impact of the
Mwaluganje elephant translocation, Kenya.
Unpublished Report to KWS. Nairobi, Kenya.
Njumbi S, Waithaka J, Gachago S, Sakwa J,
Mwathe K, Mungai P, Mulama M, Mutinda H,
Omondi P, Litoroh M. 1996. Translocation of
elephants: the Kenyan experience. Pachyderm
22: 61–65.
Okita-Ouma B, Mijele D, Amin R, Gakuya F,
Ndeereh D, Lekolool I, Omondi P, Woodley D,
Litoroh M, Bakari J, Kock R. 2008. Minimizing
competition by removing elephants from a
degraded Ngulia rhino sanctuary, Kenya.
Pachyderm 44: 80 –87.
Omondi P. 2002. Recent translocation of
elephant family units from Sweetwaters Rhino
Sanctuary to Meru National Park, Kenya.
Pachyderm 32: 39–48.
Pinter-Wollman N, Isbell LA, Hart LA. 2009.
The relationship between social behaviour
and habitat familiarity in African elephants
(Loxodonta africana). Proceedings of the Royal
Society B: Biological Sciences 276 (1659):
1009–1014.
Paglieri MA. 2018. Fence-breaking and crop-
raiding Behaviour of bull elephants in the Laikipia
Plateau, Kenya, and a proposal to modify this
behaviour. Prescott College.
Tiller LN, King LE, Okita‐Ouma B, Lala F,
Pope F, Douglas‐Hamilton I, Thouless CR. 2022.
The behaviour and fate of translocated bull African
savanna elephants (Loxodonta africana) into a novel
environment. African Journal of Ecology 00: 1–16.
Viljoen JJ, Ganswindt A, Reynecke C, Stoeger AS,
Langbauer Jr WR. 2015. Vocal stress associated with
a translocation of a family herd of African elephants
(Loxodonta africana) in the Kruger National Park,
South Africa. Bioacoustics 24 (1): 1–12.
