Population viability of captive Asian elephants in the Lao PDR

Abstract

Asian elephants Elephas maximus have been captured and trained by Lao mahouts for centuries. While captive elephants are losing their traditional relevance, they still play a significant role in the Lao logging and tourism industries. However, with only an estimated 480 captive elephants remaining nationally and only ?60 cows under 35 yr of age, the future viability of this population is uncertain. We assessed >80% of the captive elephant population and used VORTEX software to create 7 population viability analysis scenarios. Our results demonstrate that without changes to conservation management the current population is likely to be extinct in 112 yr (r = -0.099). Reduced mortality rates, increased reproductive rates and population supplementation will give the population an additional 108 yr of longevity, but will not, of themselves, prevent extinction. Management programs should direct efforts towards in situ breeding programs, a cessation in calf exportation, improved veterinary care and population supplementation. Since captive populations are also small and declining in other range nations, there is also a case for managing all Asian elephants as a single management unit.

Full text

ENDANGERED SPECIES RESEARCH
Endang Species Res
Vol. 24: 1–7, 2014
doi: 10.3354/esr00578 Published online April 9
INTRODUCTION
Asian elephant Elephas maximus populations are
in global decline. Total E. maximus numbers have
been reduced by at least 50% in all 13 range nations
in the last 3 generations (Bandara & Tisdell 2004,
Hedges et al. 2005, Choudhury et al. 2008) and the
species is classified as Endangered by the IUCN
(Choudhury et al. 2008). Total population estimates
vary between 30 000 and 50 000, although this is
widely believed to be an outdated overestimate
(Sukumar 2003, Hedges et al. 2005, Dublin et al.
2006, Hedges 2006, Choudhury et al. 2008). What
research has been undertaken has focused mainly on
wild elephants and not the sizeable captive popula-
tion (Lair 1997, Hedges et al. 2005, Hedges 2006,
Sukumar 2006). The captive elephant population
constitutes one-third to one-quarter of all remaining
Asian elephants (Sukumar 2003, Leimgruber et al.
2008). An estimated 14 500 to 16000 elephants live in
captive or semi-wild conditions, typically used for
logging, village, tourism, or temple purposes (Suku-
mar 2003, Dublin et al. 2006). While the captive pop-
ulation is a significant percentage of total elephant
numbers, these numbers are also declining (Khoun-
boline 2011).
The Lao People’s Democratic Republic (PDR) con-
tains Indochina’s largest remaining Asian elephant
population (Ahlering et al. 2011). Even so, only an
estimated 600 to 800 wild and 500 captive elephants
remain throughout Laos, with both wild and captive
populations in decline (Khounboline 2011, Ministry
of Agriculture and Forestry 2009). Major threats to
wild elephant populations include habitat loss and
© Inter-Research 2014 · www.int-res.com*Corresponding author: i.suter@uq.edu.au
Population viability of captive Asian elephants in
the Lao PDR
Ingrid Colette Suter1,*, Gilles Pierre Maurer2, Greg Baxter1
1The University of Queensland, School of Geography, Planning and Environmental Management, St Lucia, Brisbane,
Queensland 4072, Australia
2ElefantAsia, PO Box 3804, Vientiane, Lao People’s Democratic Republic
ABSTRACT: Asian elephants Elephas maximus have been captured and trained by Lao mahouts
for centuries. While captive elephants are losing their traditional relevance, they still play a signif-
icant role in the Lao logging and tourism industries. However, with only an estimated 480 captive
elephants remaining nationally and only ~60 cows under 35 yr of age, the future viability of this
population is uncertain. We assessed >80% of the captive elephant population and used VORTEX
software to create 7 population viability analysis scenarios. Our results demonstrate that without
changes to conservation management the current population is likely to be extinct in 112 yr (r =
−0.099). Reduced mortality rates, increased reproductive rates and population supplementation
will give the population an additional 108 yr of longevity, but will not, of themselves, prevent
extinction. Management programs should direct efforts towards in situ breeding programs, a ces-
sation in calf exportation, improved veterinary care and population supplementation. Since cap-
tive populations are also small and declining in other range nations, there is also a case for man-
aging all Asian elephants as a single management unit.
KEY WORDS: Asian elephants · Captive elephants · Elephas maximus · Lao PDR · Population
viability · VORTEX
Resale or republication not permitted without written consent of the publisher
This authors' personal copy may not be publicly or systematically copied or distributed, or posted on the Open Web,
except with written permission of the copyright holder(s). It may be distributed to interested individuals on request.

Endang Species Res 24: 1–7, 2014
fragmentation, poaching and human− elephant con-
flict (Norachack 2002, Sukumar 2006, Khounboline
2011). A lack of capacity and investment in conserva-
tion are also recognized as major species manage-
ment impediments (Norachack 2002, Ministry of
Agriculture and Forestry 2009).
For centuries captive elephants have shaped Lao
communities, with only minor deviations from tradi-
tional practices occurring. Both elephant acquisition
and usage have changed, bringing about a major
change in mahout lifestyle. Historically a calf would
be captured from the wild as needed by the local
mahout community. The viability of the captive ele-
phant population was never considered until the
Government of Laos introduced a ban on wild ele-
phant capture in 1989 (Sukumar 2003). This ban had
an immediate impact on the captive elephant popu-
lation, with few calves entering the population since
1989 (Fig. 1). As long as elephants were traditionally
captured from wild populations, mahouts never
needed any knowledge of elephant reproduction
(Lair 1997). As a result, the captive population now
confronts a number of demographic challenges such
as an aging population, inadequate replacement
rate, a declining number of females of reproductive
age, a lack of breeding opportunities and, recently,
excessive calf exportation (Lair 1997, Sukumar 2003,
ElefantAsia 2007, Khounboline 2011). Under CITES
rental agreements it is believed that over the past
5 yr the Government of Laos has exported an esti-
mated 10% of the nation’s calves (S. Duffillot, pers.
comm., 12 September 2012). Rentals or outright gifts
are typically granted to countries sympathetic to
Laos’ political agenda, including China, North Korea
and Japan (Suter 2012). The consequence of these
demographic challenges has led to an extremely low
captive breeding rate. In 2011, only 18 captive calves
under the age of 10 yr were documented in Laos
(Xaymountry & Maurer 2011).
Still offering much-needed employment for Lao
mahouts and communities, captive elephant indus-
tries are undergoing significant change. Tradition-
ally utilized for transportation and small-scale vil-
lage use, the majority of captive elephants in Laos
are now employed in the professional logging or
tourism industries (Suter et al. 2013). Similar to
Thailand, in less than 30 yr, elephant-based tourism
has become a principal component of the national
tourism industry (Kontogeorgopoulos 2009). The use
of captive elephants for tourism purposes has been
recognized as holding great significance for the
long-term conservation of both wild and captive
elephant populations (Duffy & Moore 2011). While
still in a nascent state, the Laos tourism industry has
become one of the most important sources of
foreign exchange and employment, and a major
contributor to the national economy (Phakdisoth &
Kim 2007, Harrison & Schipani 2009). Lao mahouts
perceive tourism to be an easier lifestyle, offering
lower pay but greater job security than the dimin-
ishing logging industry (Suter et al. 2013). Certainly
within Laos, mahouts are willing to switch to
tourism once logging in their region be comes unvi-
able (Suter et al. 2013). The Lao elephant-based
tourism industry endeavors to provide mahouts, and
the national economy, with long-term benefits, as
well as being an industry compatible with elephant
reproductive needs.
More demographic data are available for the cap-
tive elephant population in Laos than for the wild
population. Wild population numbers remain esti-
mates, with threatening processes largely uncon-
trolled. Captive elephants have been registered and
monitored by the Department of Livestock and Fish-
eries (DLF) and conservation groups, with sex, age,
location and ownership details of >80% of the entire
captive elephant population recorded (ElefantAsia
2012). This knowledge makes it easier to develop
management programmes for captive elephants than
for their wild counterparts.
Given the significance of the captive elephant
population in Laos, their decline would be detri-
mental to captive elephant populations, mahouts,
businesses and local communities. To understand
the reasons for, and the trajectory of, the declining
captive elephant population we addressed the fol-
lowing questions:
2
Fig. 1. Elephas maximus. Sex and age pyramid of the Lao
captive elephant population (n = 439). The majority of ele-
phants were captured from the wild as calves before the
1989 ban on wild elephant capture
Author copy

Suter et al.: Population viability analysis for captive elephants
(1) What is the long-term viability of Lao captive
elephants under current management regimes?
(2) Can conservation strategies prevent the local-
ized extinction of elephants?
MATERIALS AND METHODS
Study area
Our study area encompassed all districts and
provinces in the Lao PDR that had captive elephants
microchipped and registered with the DLF and Ele-
fantAsia between January 2009 and January 2012.
This included the Bokeo, Bolikhamxai, Champassak,
Luang Prabang, Oudomxay, Saravane, Sayaboury
and Vientiane provinces (ElefantAsia 2012). Once
microchipped, unique identification and demo-
graphic data were entered into the Lao national ele-
phant registration database, which we utilized for
this study.
Modelling
To assess the likelihood of Lao captive elephant ex-
tinction we carried out population viability ana lysis
(PVA) using VORTEX Version 9.5. PVA is commonly
used by researchers involved in captive breeding
groups and by conservation managers to gauge mini-
mal population via bility or extinction rates for popula-
tions at risk (Lacy 1993, Beissinger & Westphal 1998).
PVA modeling is typically integrated into conservation
planning, as programs accept assumptive parameters
and environmental variation, and allow for adaptive
species management (Akçakaya & Sjögren-Gulve
2000, Lacy 2000, Myroniuk 2004). VORTEX software
was chosen for our analyses as its simulation program
is suitable for species with low fecundity, long life
spans and uneven sex ratios (Lacy 1993, Miller & Lacy
2005). Asian elephant PVA has been undertaken on
wild populations in Sumatra (Sukumar & Santiapillai
1993), wild populations in Sri Lanka (Sukumar 2003)
and captive populations in Myanmar (Leimgruber et
al. 2008). Perhaps because of the controllable envi-
ronment in which they exist, and the substantial in-
vestments made by zoos, Asian elephant PVA has of-
ten been performed on small, ex situ populations
rather than populations in home ranges. Ex situ Asian
elephant PVA includes populations in Australian zoos
(Myroniuk 2004), North American zoos (Faust et al.
2006) and the viability of Asian elephant cows in Eu-
ropean zoos (Clubb et al. 2009).
Similar to Leimgruber et al. (2008) we ran our
model on a 500 yr timeframe rather than 100 or
1000 yr. A 100 yr timeframe may give declining pop-
ulations false indicators of population perpetuity
(Armbruster et al. 1999). Moderately longer time -
scales are recommended for populations with a neg-
ative growth rate and long generations. Given the
Lao context we considered a 1000 yr timeframe as
having too many unknown variables (political and
environmental) to provide as meaningful an analysis
as a 500 yr time scale. To test our baseline scenario
rigour we ran sensitivity analyses against 2 vital
parameters: percent of females breeding and calf
mortality. Neither increases nor decreases of 20%
affected the model.
Baseline parameters for PVA scenarios
Parameters for the 7 scenarios were determined
from the Lao national elephant registration database
and other published demographic data (Lair 1997,
Leimgruber et al. 2008, ElefantAsia 2012) (Table 1).
From the database we were able to accurately spec-
ify vital parameters, such as elephant age, sex and
initial population size. The population was consid-
ered a single, closed population with no migration,
rather than several small populations. We considered
this to be realistic as mahouts routinely buy, sell,
rent, or move elephants between pro vinces, as eco-
nomic drivers demand. Migration was not included,
as illegally exported calves will typically be un known
to ElefantAsia and not contained in the database. If
the elephant was included in the database, its entry
would be deactivated once exported and not incorpo-
rated in this analysis. Initial population size was 431,
of which 253 were cows and 178 bulls (ElefantAsia
2012). This figure includes only calves and elephants
of reproductive age. Maximum age of reproduction
for cows and bulls was 55 yr (Mar 2002, Leimgruber
et al. 2008). Carrying capacity was 517 —20% above
the current population size.
Following Leimgruber et al. (2008), the age of first
offspring and the mortality rates for bulls and cows
were considered to be alike, since we did not wish to
overstate the rate of extinction. We used infant mor-
tality rates based on Leimgruber et al. (2008) for cap-
tive elephants rather than wild elephant mortality
rates indicated by Armbruster et al. (1999) or wild
elephant mortality rates for Sri Lankan populations
(Sukumar 2003). This was considered appropriate as
captive elephants face fewer environmental threats
and have better veterinary care than wild calves.
3
Author copy

Endang Species Res 24: 1–7, 2014
Similarly, we chose an even sex ratio at birth. While
Lao mahouts believe slightly more males are con-
ceived (authors’ pers. obs.), male calves tend to have
a higher perinatal and juvenile mortality rate (Sara-
gusty et al. 2009). Juvenile bull behaviour and higher
risk-taking typically lead to higher mortality rates in
this sex (Sukumar 2003).
Percentage of breeding females was calculated by
analyzing the past 4 yr of captive elephant births
recorded in the database (ElefantAsia 2012) (Table 2).
This is the most accurate Lao captive elephant data
ever recorded, and it was considered necessary to
use actual representative values rather than breed-
ing estimates from other elephant studies. The aver-
age percentage of breeding females was low (2.3%),
but we considered this an accurate portrayal of the
current Lao context. Percentage of males in the
breeding pool was 80% (Leimgruber et al. 2008), as
social hierarchy dictates that not all bulls have the
opportunity to reproduce. However, as most calves
are sired by wild bulls, the fertility of captive bulls
remains unknown.
We did not include harvesting in any scenario, nor
did we include any wild elephant population demo-
graphics in our scenarios. With wild elephant popula-
tions poorly monitored and managed, we focused
solely on the population with known and controllable
conservation management.
RESULTS
All our simulations indicate that Laos’
captive elephant population is not self-
sustaining. The current captive population
has a negative growth rate (r = −0.099)
(Table 3). Mortality rates are higher than
reproductive rates. Our baseline popula-
tion shows the captive elephant popula-
tion is likely to become extinct in 112 yr. In
no scenario was the carrying capacity
reached. Reducing mortality, increasing
birth rates and population supplementa-
tion reduced the rate at which the popula-
tion reached extinction, but did not stop it.
Scenario 7 provided the Lao captive ele-
phant population with the longest persist-
ence, but even then our model predicted
extinction within 220 yr (Fig. 2).
DISCUSSION
Current management regimes are not
sufficient to support the long-term viability
of the Lao captive elephant population.
Our results are similar to those from
studies of Myanmar captive elephant pop-
ulations (Mar 2002, Leimgruber et al.
2008) and Thai elephants in Australian
zoos (Myroniuk 2004). However, while the
parameters used are largely represen tative
of the Lao elephant population, mortality
rates are estimates and not necessarily
representative of the true mortality rate,
particularly for calves. The 8% mortality
rate for calves taken from Leimgruber et
4
Year No. of No. of cows No. of % of births Reproductive
elephants 15−55 yr births (population) rate
2008 432 229 5 1.16 2.2
2009 434 231 3 0.69 1.3
2010 440 232 7 1.59 3
2011 439 226 6 1.37 2.7
Total 21 1.20 2.3
Table 2. Elephas maximus. Reproductive rate of captive cows in Laos
from 2008 to 2011. New elephants were added to the database as they
were microchipped
Parameter Description
BASELINE
Mating system Polygynous, 80% of males and 2.3%
females in breeding pool
Sexual maturity 15 yr for both sexes, maximum
reproductive age 55 yr
Litter size 1 with a 1:1 sex ratio at birth
Initial population structure Specified aged distribution
Age (yr) Mortality (%)
0−5 8
5−15 2.1
>15 2.9
Initial population size 431
Carrying capacity 512
MODEL ITERATIONS
Scenario 1 Current captive/baseline population
Scenario 2 Scenario 1 + 5% higher fecundity
Scenario 3 Scenario 1 + 10% higher fecundity
Scenario 4 Scenario 2 + 50% lower mortality
Scenario 5 Scenario 3 + 50% lower mortality
Scenario 6 Scenario 5 + 5 calves supplemented
Scenario 7 Scenario 5 + 10 calves supplemented
Table 1. Elephas maximus. Baseline parameters and 7 management
scenarios applied in VORTEX for Lao captive elephant population viabil-
ity analyses. Age applies to both sexes. All model scenarios were repeated
1000 times over 500 yr
Author copy

Suter et al.: Population viability analysis for captive elephants
al. (2008) may be too high, producing an excessive ex-
tinction rate. Understanding the real mortality rates for
this population will provide greater accuracy in fur-
ther population viability analysis. Furthermore, in-
creased funding for additional conservation manage-
ment will permit a greater delivery of services. This
will facilitate improved reproductive and veterinary
efforts. We suggest conservation management aims to
provide better outreach services to mahouts and their
elephants, ensuring a regular birth and death census,
as well as services to lower elephant mortality rates
and increase fecundity rates, and the consideration of
population supplementation.
Reducing mortality rates
Very little information is known about mortality
rates and the official causes of death among cap tive
Lao elephants. Deaths are often under reported by
mahouts; post mortems are rarely performed, and
there is minimal access to laboratories for blood
and tissue analysis (Labatut & Suter 2010). While the
healthcare of captive elephants is improving, a lack of
robust knowledge about disease and in fection rates
combined with a lack of national capacity to contain
potential disease outbreaks should be recognized as
major threats to captive elephants. A reduction in
mortality rates should, therefore, focus on continued
veterinary checks, mahout education, improving lab-
oratory facilities and disease diagnosis, infectious dis-
ease assessments and more frequent post mortem
analysis. Emerging diseases such as elephant en-
dotheliotropic herpesvirus and tuberculosis represent
addition threats to elephants. No studies have been
performed to assess wild elephant disease or infection
rates. Pregnant cows and calves should be identified
and monitored on a quarterly or biannual basis and
the owner should be contacted regularly by telephone
to determine the elephants’ health status.
Increasing fecundity rates
The small number of reproductively vi -
able females inhibits significant popula-
tion growth, although an increase in
fecundity does assist population persist-
ence. The tourism and export industries
are driving demand for calves, with pur-
chase prices reaching >$30 000 US (Suter
et al. 2013). The high price for calves may
now be a very good financial incentive for
mahouts to undertake breeding programs,
5
Scenario Growth Probability of Time until first Years until
rate extinction (%) extinction extinction
1 −0.099 100 41.06 ± 25.86 112
2 −0.081 100 45.42 ± 27.77 136
3 −0.064 100 53.05 ± 32.92 183
4 −0.064 100 58.85 ± 38.52 154
5 −0.047 100 70.74 ± 49.60 219
6 −0.064 100 65.26 ± 41.36 180
7 −0.047 100 74. 36 ± 52.35 220
Table 3. Elephas maximus. Growth rates and extinction risk of 7 popula-
tion viability scenarios for Lao captive elephants. Time until first extinc-
tion is given as mean ±SD; scenarios are described in Table 1
Fig. 2. Elephas maximus. VORTEX population trajectories of the captive Lao population, in a 500 yr simulation time period.
(a) The baseline scenario indicates extinction in 112 yr, whereas (b) the Management Scenario 7 indicates extinction in 220 yr
Author copy

Endang Species Res 24: 1–7, 2014
and more mahouts should be encouraged to partici-
pate. Conservation management should identify and
target the owners of cows 30 yr and under for breed-
ing incentives. There have previously been arrange-
ments between non-governmental organizations and
mahouts to enable their cows to breed, demonstrat-
ing that Lao ma houts are willing to stop work for con-
servation measures if economic losses are not
incurred (Suter 2011). Training in estrus detection is
also an important skill for mahouts to develop. How-
ever, it must be ensured that calves born as a result of
breeding programmes are kept in the country and
not rented or sold to other nations by the Govern-
ment of Laos.
Population supplementation
Our analysis indicates that calf supplementing pro-
vides the population with greater persistence than
increasing female reproduction rates or reducing
mortality. We propose a transparent rental agree-
ment from another range nation of Elephas maximus
indicus as a method to safeguard the Lao elephant
population. Rental agreements regarding Appendix
1 species are permitted under CITES regulations, to
which Laos, Thailand and India are all signatories
(Choudhury et al. 2008). Additions of new elephants
may be expensive, but could prevent extinction of
the Lao captive elephant population. An Interna-
tional Non-Government Organisation could organize
the rental agreements and be responsible for man-
agement of the elephants and a breeding program
while they are in Laos. While supplementation would
be an arduous task, it may be unnecessary if all
calves born into captivity are accounted for and used
for in situ reproductive purposes rather than ex ported
for diplomatic purposes. If exportation continues, a
transparent rental agreement with another range
nation of E. m. indicus may be necessary to avoid
regional extinction.
Management implications
The analyses reported here used the best available
estimates of population parameters for captive ele-
phants in Lao PDR. These findings suggest that,
while still important for industries and communities,
the Lao captive elephant population requires greater
management for population persistence; therefore, it
should not be considered as a separate management
unit. Rather, management of the captive Asian ele-
phant population should be conducted across
national boundaries in order to establish a greater
chance of preventing regional extinction. This man-
agement may take the form of transfers of young to
supplement local populations and prevent the
genetic problems associated with small population
sizes. It may also be feasible to set targets for the
growth of regional populations and to provide incen-
tives or rewards for meeting those targets. While dis-
cussion continues concerning greater cooperation
between range nations, in reality, actions and fund-
ing toward this goal have so far been insignificant
(Lair 2002, Dublin et al. 2006). Funding for Lao cap-
tive elephant management is urgently needed if this
regionally significant population is to persist.
Acknowledgements. The authors appreciate the assistance
given by the Department of Livestock and Fisheries’ director
Dr. Bounkouang and the National Animal Health Center’s
director Dr. B. Douangneun. We also thank the staff at Ele-
fantAsia, specifically S. Duffillot, T. Douangdy and V. Chan-
thavong for database compilation and the intrepid task of
captive elephant microchipping. Veterinarians supervising
the Mobile Veterinary Unit field missions included Dr. B.
Bouchard, Dr. J. Lassausaie and Dr. A. Bret. ElefantAsia
appreciates the financial support received from Critical Eco-
systems Partnership Fund to microchip and to create the Lao
national elephant registration database.
LITERATURE CITED
Ahlering M, Hedges S, Johnson A, Tyson M, Schuttler S,
Eggert L (2011) Genetic diversity, social structure, and
conservation value of the elephants of the Nakai Plateau,
Lao PDR, based on non-invasive sampling. Conserv
Genet 12: 413−422
Akçakaya H, Sjögren-Gulve P (2000) Population viability
analyses in conservation planning; an overview. Ecol
Bull 48: 9−21
Armbruster P, Fernando P, Lande R (1999) Time frames for
population viability analysis of species with long genera-
tions: an example with Asian elephants. Anim Conserv 2:
69−73
Bandara R, Tisdell C (2004) The net benefit of saving the
Asian elephant: a policy and contingent valuation study.
Ecol Econ 48: 93−107
Beissinger M, Westphal MI (1998) On the use of demo-
graphic models of population viability in endangered
species management. J Wildl Manag 62: 821−841
Choudhury A, Lahiri Choudhury DK, Desai A, Duckworth A
and others (2008) Elephas maximus. www. iucn redlist
.org/ apps/redlist/details/7140/0 (accessed 19 April 2011)
Clubb R, Rowcliffe M, Lee P, Mar K, Moss C, Mason G
(2009) Fecundity and population viability in female zoo
elephants: problems and possible solutions. Anim Welf
18: 237−247
Dublin H, Desai AA, Hedges S, Vié JC, Bambaradeniya C,
Lopez A (2006) Asian Elephant Range States Meeting,
24–26 January 2006, Juala Lumpur, Malaysia Report. In:
6
Author copy
➤
➤
➤
➤

Suter et al.: Population viability analysis for captive elephants
IUCN Species Survival Commission (ed) Elephant Range
States Meeting, Kuala Lumpur. www.cites.org
Duffy R, Moore L (2011) Global regulations and local prac-
tices: the politics and governance of animal welfare in
elephant tourism. J Sustainable Tourism 19: 589−604
ElefantAsia (2007) Report: condition of Lao domesticated
elephants 2007. ElefantAsia, Vientiane
ElefantAsia (2012) ElefantAsia (V1-7) database. ElefantAsia,
Vientiane
Faust LJ, Thompson SD, Earnhardt JM (2006) Is reversing
the decline of Asian elephants in North American zoos
possible? An individual-based modeling approach. Zoo
Biol 25: 201−218
Harrison D, Schipani S (2009) Tourism in the Lao People’s
Democratic Republic. In: Hitchcock M, King VT, Parn-
well M (eds) Tourism in Southeast Asia: challenges and
new directions. Nordic Institute of Asian Studies, Copen-
hagen, p 172–180
Hedges S (2006) Conservation. In: Fowler MT, Mikota S
(eds) Biology, medicine, and surgery of elephants. Black-
well Publishing Professional, Ames, IA, p 475–488
Hedges S, Tyson M, Sitompul A, Kinnaird M, Gunaryadi D
(2005) Distribution, status, and conservation needs of
Asian elephants (Elephas maximus) in Lampung
Province, Sumatra, Indonesia. Biol Conserv 124: 35−48
Khounboline K (2011) Current status of Asian elephants in
Lao PDR. Gajah 35: 62−66
Kontogeorgopoulos N (2009) Wildlife tourism in semi-
captive settings: a case study of elephant camps in north-
ern Thailand. Curr Issues Tourism 12:429– 449
Labatut F, Suter I (2010) The veterinary care of domesticated
elephants in Laos by a mobile veterinary unit. Gajah 32:
21−26
Lacy R (1993) VORTEX: a computer simulation model for
population viability analysis. Wildl Res 20: 45−65
Lacy RC (2000) Considering threats to the viability of small
populations using individual-based models. Ecol Bull 48:
39−51
Lair R (1997) Gone astray: the care and management of the
Asian elephant in domesticity. Food and Agriculture
Organization of the United Nations, Bangkok
Lair R (2002) A regional overview of the need for registration
of domesticated Asian elephants. In: Baker I, Kashio M
(eds) Giants on our hands: Proc Int Workshop on the
domesticated Asian elephant, 5–10 February 2001,
Bangkok. UN FAO Regional Office for Asia and the
Pacific, Bangkok, p 8–13
Leimgruber P, Senior B, Uga, Aung M and others (2008)
Modeling population viability of captive elephants in
Myanmar (Burma): implications for wild populations.
Anim Conserv 11: 198−205
Mar K (2002) The studbook of timber elephants of Myanmar
with special reference to survivorship analysis. In: Baker
I, Kashio M (eds) Giants on our hands: Proc Int Workshop
on the domesticated Asian elephant, 5–10 February
2001, Bangkok. UN FAO Regional Office for Asia and the
Pacific, Bangkok, p 195–211
Miller P, Lacy R (2005) VORTEX: a stochastic simulation of
the extinction process, Version 9.50’s user’s manual.
Conservation Breeding Specialist Group (SSC/IUCN),
Apple Valley, MN
Ministry of Agriculture and Forestry (2009) National Ele-
phant Management Action Plan: Lao PDR. Vientiane,
Lao PDR
Myroniuk P (2004) Population viability analysis of captive
Asian elephants in Australia: a conservation assessment.
Humane Society International Australia. www. hsi. org. au/
editor/ assets/ legal/ PVA_ Report.pdf (accessed 5 Decem-
ber 2011)
Norachack B (2002) The care and management of domesti-
cated Asian elephants in Lao PDR. In: Baker I, Kashio M
(eds) Giants on our hands: Proc Int Workshop on the
domesticated Asian elephant, 5–10 February 2001,
Bangkok. UN FAO Regional Office for Asia and the
Pacific, Bangkok, p 172–180
Phakdisoth L, Kim D (2007) The determinants of inbound
tourism in Laos. ASEAN Econ Bull 24: 225−237
Saragusty J, Hermes R, Göritz F, Schmitt DL, Hildebrandt
TB (2009) Skewed birth sex ratio and premature mortal-
ity in elephants. Anim Reprod Sci 115: 247−254
Sukumar R (2003) The living elephants: evolutionary ecol-
ogy, behavior, and conservation. Oxford University
Press, New York, NY
Sukumar R (2006) A brief review of the status, distribution
and biology of wild Asian elephants Elephas maximus.
Int Zoo Yearb 40: 1−8
Sukumar R, Santiapillai C (1993) Asian elephant in Suma-
tra population and habitat viability analysis. Gajah 11:
59−63
Suter I (2011) Luxembourg Government assists with Lao
elephant reproduction. Available at: www. elefantasia.
org/ spip. php? article 160 &lang=en (accessed 5 December
2013)
Suter IC (2012) Really Laos, you shouldn’t have: giving ele-
phants to Japan is a bad idea. http: // the conversation.
edu. au/ really-laos-you-shouldnt-have-giving-elephants-
to-japan-is-a-bad-idea-9778 (accessed 13 September
2013)
Suter IC, Hockings M, Baxter G (2013) Changes in elephant
ownership and employment in the Lao PDR: implications
for the elephant-based logging and tourism industries.
Hum Dimens Wildl 18: 279−291
Xaymountry B, Maurer G (2011) Note on domesticated ele-
phant management in Lao PDR. ElefantAsia, Vientiane
7
Editorial responsibility: Nils Bunnefeld,
Stirling, UK
Submitted: September 13, 2013; Accepted: January 7, 2014
Proofs received from author(s): March 7, 2014
Author copy
➤
➤
➤
➤
➤
➤
➤
➤
➤
➤