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1 Research Center for Climate Change, University of Indonesia, Gd. PAU Lt. 8.5, Kampus UI, Depok 16424, Indonesia
2 South Australian Herpetology Group, South Australian Museum, North Terrace, Adelaide, SA 5000, Australia
3 Nature Exploraons & Educaon Team, No. B-1/G-6, De Soysapura Housing Scheme, Moratuwa 10400, Sri Lanka
4 Wildlife Management Internaonal, PO Box 530, Karama, NT 0813, Australia
5 No. 15/1, Dolosbage Road, Gampola, Sri Lanka
6 Crocodile Conservaon Services Europe, RoedelheimerLandstrasse 42, Frankfurt 60487, Germany
1 thasun@rccc.ui.ac.id (corresponding author), 2 majintham@yahoo.com, 3 dmsameera@gmail.com,
4 cmanolis@wmi.com.au, 5 kalds@sltnet.lk, 6 crocodilians@web.de
ISSN 0974-7907 (Online)
ISSN 0974-7893 (Print)
hp://dx.doi.org/10.11609/JoTT.o4159.7111-30
B.C. Choudhury [Retd.], Wildlife Instute of India, Dehradun, India. 26 April 2015 (online & print)
Ms # o4159 | Received 26 September 2014 | Final received 26 February 2015 | Finally accepted 27 March 2015
Amarasinghe, A.A.T., M.B. Madawala, D.M.S.S. Karunarathna, S.C. Manolis, A. de Silva & R. Sommerlad (2015). Human-crocodile conict and conserva-
on implicaons of Saltwater CrocodilesCrocodylus porosus(Replia: Crocodylia: Crocodylidae) in Sri Lanka. Journal of Threatened Taxa 7(5): 7111–7130; hp://
dx.doi.org/10.11609/JoTT.o4159.7111-30
© Amarasinghe et al. 2015. Creave Commons Aribuon 4.0 Internaonal License. JoTT allows unrestricted use of this arcle in any medium, repro-
ducon and distribuon by providing adequate credit to the authors and the source of publicaon.
Self funding of AATA, MBM, and DMSSK
The authors declare no compeng interests.
For and
see end of this arcle
Human-wildlife conict occurs when human requirements encroach on those of wildlife populaons, with potenal costs to
both humans and wild animals. As top predators in most inland waters, crocodilians are involved in human-wildlife conicts in many
countries. Here we present ndings of a 5-year survey on human-crocodile conict on the island of Sri Lanka and relate the results to
improving management pracces. We aimed to quanfy and understand the causes of human-crocodile conict in Sri Lanka, and propose
soluons to migate it. Visual encounter surveys were carried out to esmate the populaon size of Saltwater Crocodiles. We recorded
778 sighngs of Saltwater Crocodiles at 262 of 400 locaons surveyed, and esmate the total populaon to comprise more than 2000
non-hatchlings and to have increased at an average rate of 5% p.a. since 1978. We propose four crocodile vigilance zones within the wet
zone and one crocodile vigilance zone within the dry zone of the country. Specic threats to Saltwater Crocodiles idened in crocodile
vigilance zones were: habitat destrucon and loss; illegal killing and harvesng (17 killings out of fear, ~200 incidents of killing for meat
and skins, ~800 eggs annually for consumpon); unplanned translocaons; and, interacon with urbanizaon (10 incidents of crocodiles
being run over by trains/vehicles and electrocuon). Addionally, 33 cases of crocodile aacks on humans were recorded [8 fatal, 25 non-
fatal (minor to grievous injuries)] and more than 50 incidents of aacks on farm and pet animals.
habitat loss, hunng, road kills, policy and planning, translocaon, crocodile vigilance zones
DATA
DEFICIENT
DD
NOT
EVALUATED
NE
NEAR
THREATENED
NT
VULNERABLE
VU
ENDANGERED
EN
EXTINCT
IN THE WILD
EW
EXTINCT
EX
CRITICALLY
ENDANGERED
CR
LEAST
CONCERN
LC
Crocodylus porosus
Saltwater Crocodile
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
Human-wildlife conict is a growing issue worldwide
(Woodroe et al. 2005) and crocodilians are one of the
major groups involved (Lamarque et al. 2009). Sri Lanka
is a relavely small island of approximately 65,500km2,
but home to large populaons of crocodiles and other
large wild animals (e.g., elephants, leopards, sloth
bears, etc.), as well as humans. The human populaon
density in Sri Lanka’s biologically richest wet zone
(southwest), is one of the highest on earth (Cincoa et
al. 2000), and is growing more rapidly around protected
areas (Wiemyer et al. 2008) and in developing coastal
cies such as Colombo, Negombo, Galle, Matara, and
Hambantota. As a result, human-crocodile conict
(HCC) is increasing.
Two allopatric species of crocodiles occur in Sri Lanka;
the Mugger Crocodile, Crocodylus palustris Lesson, 1831,
and the Saltwater or Estuarine Crocodile, Crocodylus
porosus Schneider, 1801 (Deraniyagala 1939). The
Saltwater Crocodile is the largest living reple on Earth;
it can grow up to 6–7 m (Webb et al. 1978; Whitaker
& Whitaker 2008; Erickson et al. 2012). Like other
crocodilians it is an opportunisc feeder, using acve
hunng or ‘sit and wait’ strategies (Cooper & Jenkins
1993), and the frequency of dierent prey items varies
signicantly with habitat and body size (Taylor 1979;
Webb & Manolis 1989). Although telemetry studies are
increasing our knowledge of movement paerns and
extent of home ranges for Saltwater Crocodiles (e.g.,
Webb & Messel 1978; Kay 2004; Read et al. 2007; Brien
et al. 2008; Campbell et al. 2013, 2014; Hanson et al.
2014), which can assist management eorts, there is sll
a paucity of informaon for most range states for the
species, including Sri Lanka.
Saltwater Crocodiles are distributed in a wide variety
of saline and freshwater habitats, including rivers and
creeks, coastlines, coastal ood plains, lagoons, swamps,
river and canal oualls (e.g., see Webb & Manolis 1989;
Letnic & Connors 2006). Although popularly referred to
as ‘sales’ in Sri Lanka, a high proporon of the Saltwater
Crocodile populaon exists in freshwater habitats in the
western and southern parts of the country (e.g., Nilwala,
Bentota, Kelani, Maha Oya; de Silva 2013), including
Colombo, the capital (Devapriya 2004; Jayawardene
2004; Porej 2004; Samarasinghe 2014).
Under Sri Lankan legislaon the Saltwater Crocodile
is listed as ‘endangered’ (MOE 2012). In the 1970s,
Whitaker & Whitaker (1977, 1979), urged the Sri
Lankan Government to establish a sanctuary in which
Saltwater Crocodiles would be protected and could live
without conict with humans. In reality the species
has received “paper protecon” (Whitaker 2004), with
the responsible wildlife authority, the Department
of Wildlife Conservaon (DWC), handling crocodile
issues without sucient bio-geographical, taxonomic,
behavioural or ecological understanding of the species.
Some management measures, such as the translocaon
of ‘problem’ crocodiles, have ended with crical
arguments, media debates, and dead or disappeared
crocodiles.
This publicaon aims at quanfying and
understanding the causes of HCC in Sri Lanka, and
proposes soluons to migate it. We also provide new
insights into the social and biological context in which
crocodile conservaon and management programs
could operate in Sri Lanka.
Between January 2008 and December 2012 we
visited 400 locaons within Gampaha, Colombo,
Kalutara, Galle and Matara Districts in the ‘wet zone’ of
the country (Image 1), including beaches from Negombo
on the west coast to Matara on the south coast. We
divided specic survey areas in the wet zone into four
regions (Images 2–5). Systemac surveys in the dry
zone could not be carried out due to civil unrest, but
some sighngs of Saltwater Crocodiles were recorded
during general visits to some parts of the area.
Spotlight and dayme surveys were carried out from
boats in rivers, lagoons and other large water bodies,
and we supplemented these counts with other personal
observaons (both day and night) along small streams
and canals, marshes, and other small water bodies. We
approached crocodiles that were sighted, as close as
possible to conrm the species and to esmate their
size. All spotlight survey sighngs were recorded as
“eyes only”.
Each region was surveyed during dierent me
periods (January 2008–March 2009; April 2009–June
2010; July 2010–September 2011; and October 2011–
December 2012). In all, approximately 500 kilometers
were surveyed during the 5-year period, represenng
around 75% of the available habitat for Saltwater
Crocodiles.
We also examined severalSaltwater Crocodiles that
had been captured by villagers, unknown groups and
wildlife authories. We photographed color paerns
on the anks and tails of these animals, and other
characteriscs (e.g., body size, amputaons) were
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
noted for future idencaon. These crocodiles were
translocated by the wildlife authories to naonal
parks. Aer translocaon, we aempted to ascertain
the fate of the animals through direct observaon
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
[e.g. using binoculars (7x50) from jeeps]. Anand et
al. (2013) reported that 16 crocodiles (14M: 2F) were
captured and translocated to inland water bodies and to
Muthurajawela (in Colombo). These animals were not
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
responsible for aacks on people, and as we could not
observe them post-release, they were not included in
our analysis.
We interviewed people living around the crocodile
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
capture locaons to idenfy the extent of HCC. On the
basis of the survey and interview results we idened
zones of high HCC incidence involving Saltwater
Crocodiles within the survey regions, which we refer to
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
as “Crocodile Vigilance Zones” (CVZ): RHW - Ragama-
Hendala-Waala; MDW - Moratuwa-Dehiwala-
Wellawaa; BBA - Beruwala-Bentota-Ambalangoda;
MMA - Matara-Malimbada-Akuressa.
We recorded 778 sighngs of Saltwater Crocodiles
within 262 of the 400 sites visited. The majority of
sighngs were recorded during the day (82.5%), and the
remainder from spotlight surveys (17.5%). We esmate
that 25 crocodiles counted during dayme surveys were
re-counted during spotlight surveys, and 98 sighngs
were hatchlings (<60cm total length).
Most (64%) of the sighngs were from the Nilwala
River basin (140, 18%); Bentota and Meegama river
basins (102, 13%); Dutch-Hamilton Canals and Ja-Ela
River (106, 13%); and the Bolgoda River and Lake (154,
20%). We also observed Saltwater Crocodiles in the
sea or on the seashore at Matara, Beruwala, Bentota,
Induruwa, Balapiya, Kollupiya, Bambalapiya,
Dehiwala, and Ratmalana. A higher proporon of
sighngs (57%) were recorded from dal and non-dal
rivers, than from the coast and freshwater lakes (Fig. 1).
On the basis of the dayme surveys, where crocodile
size esmates were available, juveniles (immature
non-hatchlings) comprised an esmated 55–60% of
non-hatchling sighngs (see Fig. 2). Given that small
crocodiles are not as easily sighted as large crocodiles
during dayme surveys (Webb et al. 1990), it is likely
that juveniles comprise a higher proporon of the
populaon than is indicated by our results. Hatchlings
were sighted in each of the survey regions, but the
highest numbers were recorded from habitats with well-
established vegetaon, such as mangroves and riverine
forests.
To derive a total populaon esmate, we excluded
hatchlings and the duplicate counts, applied conservave
correcon factors of 1.59 to spotlight counts and 2.50 to
dayme counts (Bayliss et al. 1986; Webb et al. 1990),
and applied a correcon factor of 1.33 to account for
habitat that was not surveyed/visited. The current total
populaon is thus esmated to be at least 2000 non-
hatchling Saltwater Crocodiles. Bearing in mind that the
correcon factors that we used to account for sightability
are conservave, and no aempt was made to correct
for seasonal biases or annual increases in the populaon
between 2008 and 2014, this esmate is considered to
be an underesmate of the real populaon size.
Interesngly, half of the interviewees who use the
water source for daily acvies were not aware of the
abundance of crocodiles as was observed during the
study.
The major threats observed for Saltwater Crocodiles
in Sri Lanka were: encroachment of human selements;
habitat loss and destrucon (draining and relling of
wetlands, conversion of mangroves and coastal habitats
for prawn farms, sand extracon, developing tourist
hotels (including high intensity lighng), unplanned
road/railway construcons); road/rail kills; and,
increased shing acvies in the country. In parcular,
the removal of riverine forests and the reclamaon
of swamps directly aect Saltwater Crocodile nesng
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
habits and habitats. Many crocodile habitats are
surrounded by shing villages and tourism zones, and
the animals in these habitats are potenally impacted
by motor boat acvity, oil, noises, garbage, polythene,
discarded shing nets, and shing tools. We observed
higher densies of crocodiles around areas where
garbage is dumped and which are covered with alien
invasive plants - these habitats may be considered as
refuge habitats for crocodiles in urban environments.
It is possible that crocodiles are aracted to garbage
dumps due to the smell of rubbish or other prey items
such as rats, birds, dogs, which are aracted to dumped
food.
Two-hundred incidents of direct and incidental take
of non-hatchling Saltwater Crocodiles were recorded
(Fig. 3, Table 1), somemes as revenge aer an aack
on family members (or friends), but mainly for meat and
skins (Images 6, 7). Juvenile crocodiles (40–120 cm total
length) accounted for 80% of the total take, and most
(90%) of them were caught incidentally in shing nets
(Fig. 3, Image 8) or prawn traps; the remaining 10% were
taken as a result of direct hunng. Even the smallest
crocodiles are consumed, aer being fried or smoked.
Crocodile meat is sold in surrounding areas and
somemes distributed free amongst neighbours. We
observed crocodile meat being mixed together with
and sold as shark meat—one kilogram of crocodile
meat in the Ragama-Handala-Waala area sold for 300
Sri Lankan Rupees (approximately $US 2.50), whereas
shark meat sells for around 900 Rupees (approximately
$US 7.50/kg). While transporng crocodile meat out
of an area, hunters use sh containers to hide it from
police ocers.
Most skins were reportedly purchased by ‘foreigners’,
usually aer being tanned, but a few are in raw salted
form. However, we saw no evidence of products or
handicras being manufactured from crocodile skin,
although such illegal acvity may operate covertly.
We esmate that over 800 Saltwater Crocodile
eggs (equivalent to around 40 nests) were illegally
harvested annually for consumpon during the 5-year
survey period (Fig. 4). Although the full extent of
Saltwater Crocodile nesng is unknown at this me,
this level of illegal harvest is considered to involve a
high proporon of nests that are produced. We also
observed approximately 20 nests that were predated by
domesc dogs, Water Monitor Varanus salvator, Land
Monitor V. bengalensis, Wild Boar Sus scrofa, Jackal
Canis aureus, Python Python molurus, Painted Stork
Mycteria leucocephala and Asian Openbill Anastomus
oscitans, and some cases of cannibalism.
Nine crocodiles were run over by trains and other
vehicles, and one individual was observed electrocuted
in the Ragama area.
Due to the loss of human life, aacks and
general increase in HCC, The Department of Wildlife
Conservaon (DWC) started to translocate Saltwater
Crocodiles from areas of conict. Most of the suspected
‘problem’ Saltwater Crocodiles were captured and
A
BC
Capture (to
translocate)
Nest har-
vesng
Incidental
trap
Kill (fear/
revenge)
Aack on
human
Run over by
train/vehicle
Hunng
(meat/skin)
0 20 40 60 80 100
© M.B. Madawala
© P.D. Weerarathna © M.B. Madawala
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
MMA
12 Mar 2008 Hungangoda -
Hakmana 2.5m
Killed by villagers due to
animal staying around
bathing place.
Double-sided iron hooks with
chicken as bait were used
for capture. Cut with an axe
and hit with poles and large
stones.
Villagers
10 Jul 2008 Kamburupiya 2.5m
28 Aug 2009 Nandugala 2m
23 Feb 2010 Vigala 2.5m
2 Sep 2010 Malimbada -
Akuressa 2m
4 Mar 2011 Keerantota -
Akuressa 2.5m
20 Apr 2011 Kakanadura 2m
17 Mar 2012 Tihagoda 2m
BBA
15 May 2010 Beruwala 3m Killed by villagers out
of fear.
18 May 2011 Munhena -
Beruwala 2m Killed by villagers out
of fear.
Hit with poles and large
stones
Villagers.
Aer killing the animal, meat divided
amongst villagers to consume. A
consumed So-shell Turtle was
observed in the gut.
22 Dec 2011 Beruwala
(Fig. 9A) 4m
Aempted to kill by
villagers out of fear.
People believed that
this crocodile will aack
their children
Two large single-sided iron
hooks (50 & 75 mm long)
were used (Image 6B-C). Type
of bait unknown.
Villagers and DWC.
Animal captured on 22 December
and then informed to DWC, but they
were late three days. The animal was
weak and died on the way to the zoo
when taking the animal to a surgery
to remove the hooks in the mouth
and stomach. See footnote (1) for
postmortem details.
12 Sep 2012 Payagala -
Beruwala 2.5m
Killed by villagers due to
aacks on livestock and
coming into the kitchen
of a house. Killed using
bait the day aer it
was chased back to the
waterbody.
Double-sided iron hooks with
chicken bait used for capture.
Hit with poles and large
stones.
Villagers. Aer killing the animal the
meat was divided amongst villagers
to consume.
2012 Moragalla -
Beruwala -
Killed by villagers as
they assumed this
animal was responsible
for the death of a male
(40 yr) in that area.
Unknown, cut marks on the
head observed Villagers
RHW
8 Feb 2012
Meda Marsh
Dutch Canal
(Fig. 10A)
5m
Killed by villagers as
they assumed this
animal was responsible
for the death of a male
(36 yr) in that area.
A large single-sided iron
hook (15cm long and 12mm
diameter) and double-sided
iron hooks (Image 7B) were
used to capture with chicken
bait. Head was cut using an
axe and beaten using poles
aer approximately 6 hours
of capturing.
Villagers and DWC.
Animal captured at 04.00hr and
then informed to DWC, who arrived
aer 12 hours. [Traveling me from
nearest DWC oce (Western Regional
Oce, Miriswaa, Gampaha) to
the locaon, which is around 25km,
is approximately 1.5 hours!]. See
footnote (2) for postmortem details.
22 May 2012 Wanata - Horape 4m
Killed by villagers out of
fear based on previous
experience in Ragama.
Double-sided iron hooks with
chicken bait used for capture.
Cut with an axe and hit with
poles and large stones.
Villagers
31 Dec 2012 Manelgama -
Kelaniya 3m
Killed by villagers due to
aacks on livestock and
a pet dog.
Double-sided iron hooks
used (specially made to kill
this crocodile) to capture
with chicken bait. Cut with a
machete and hit with poles.
Villagers
MDW
19 Feb 2009 Wewala -
Piliyandala 3m Killed by villagers out
of fear.
Double-sided iron hooks
used to capture with chicken
bait. Hit with poles and large
stones.
Villagers
11 Aug 2012 Hasungala -
Moratuwa 3m Killed by a villager out
of fear.
Shot using a 12-gauge single
barrel shotgun. A villager
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
released into inland freshwater pools which are already
heavily populated by Mugger Crocodiles. During the
period of this study DWC released crocodiles to inland
pools at Udawalawa, Bundala and Yala Naonal Parks
(see Fig. 5, Table 2), and recently to Lunugamwehera
Naonal Park (aer the study).
Field observaons since 2000 indicate that Muggers
and Saltwater Crocodiles do not share the same wild
habitats, except for a few localies where they may
overlap seasonally due to the migraon paerns of
the laer, which are known to move long distances
(e.g., Allen 1974; Manolis 2005; Read et al. 2007). For
MMA
Apr 2010 Walgama -
Matara 2m
Road kill Run over by train Railway development authories
and DWC
Jul 2011 Guruganga
Kamburugamuwa 2.5m
Apr 2012 Pamburana -
Matara 2m
BBA
Feb 2008 Madampe -
Ambalangoda 2m
Jul 2010 Seenigama - Galle 2m
15 Apr 2010 Mawala -
Ambalangoda 1.5m Road kill Run over by vehicles Road development authories and
DWC
RHW
19 May 2010 Waala 2.5m Road kill Run over by train Railway development authories
and DWC
30 Mar 2013 Mabola 2.5m
Improper planning of
electricity supply to
Katunayake-Colombo
Highway project
Electrocuon Electricity board, road development
authories and DWC
MDW
Feb 2012 Karadiyana -
Piliyandala 1m Road kill Run over vehicles Road development authories and
DWC
Nov 2012
(1) Died on 22 December 2011. Beruwala crocodile (Image 6A) was taken by DWC to surgery for removal of hooks by zoo authories; the animal was injured by
two hooks, one speared the stomach (Image 6B) and other in the mouth (Image 6C), and very bad smell coming from its mouth. The animals died on the way to the
zoo before surgery. Polythene, shopping bags, ferlizer bags and bone parts were found in the gut. (2) Died on 8 February 2012. Ragama crocodile (Image 7A) was
taken for postmortem by DWC; bleeding at several places on the throat and limbs, head damaged (behind le eye), 10cm deep, 15cm inches wide, cut with an axe
(Image 7C), second nger of le foot cut. Seven Black Turtles Melanochelys trijuga thermalis (Image 7D), ~300g of polythene (Image 7E), ~500g of ferlizer bags, ~2kg
of bone parts, ve claws of a Fishing Cat Prionailurus viverrinus, and a hand and a leg of a human were found in the gut.
A
B
C
D E
© J. Ranasinghe
© M.B. Madawala © M.B. Madawala
© M.B. Madawala
© M.B. Madawala
© M.B. Madawala
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
example, the two species are sympatric during some
seasons in the estuary of the Walawe River Basin, and
a few localies between Tangalle-Hambantota, Yala
Naonal Park and Bundala Naonal Park, although the
laer two localies could reect introduced populaons
resulng from translocaon acvies.
The translocaon methods used by DWC and
unknown groups (Image 9) are considered unacceptable,
as there is a high risk of crocodiles being injured during
transportaon. The types of enclosure being used are
not appropriate for safe translocaon (Image 10), and
their design should consider the health and well-being of
the animals (Image 11). In Yala and Udawalawa naonal
parks we observed that within a few days, for most of
MMA
2010
Dondra
lighthouse -
Matara
3.5m
No reason idened,
also no record of
harm
Unknown
Released to one of the best Mugger habitats in Udawalwa NP.
Muggers observed chasing it (injured) and disappeared aer.
Most probably dead.
15 Feb 2012 Malimbada
(Nilwala RB) 4m Suspected of killing
school girl (18 yrs.)
Using a steel
cage, bait was not
conrmed.
Released in Buthawa Wewa Lake (one of the best Mugger
habitat) in Yala NP. Couldn’t observe aer two days, but trackers
said that it was seen up unl May 2013 in Wilapala Wewa, and
disappeared aer.
19 Apr 2012 Matara sea
shore 4.5m
No reason idened,
also no record of
harm
Using ropes Released in Yala NP. Was not observed three days aer release.
RHW
23 Feb 2009 Kalu Ela
Hekia - Waala 5m Killed chickens and
pets
Trap set up by
villagers
Released in one of the best Mugger habitats in Udawalwa
NP. Observed Muggers aacked and injured and no record
aerwards. Aer one week saw a dead body of a huge crocodile
(couldn’t conrm identy as carcase had no idenable marks).
13 Feb 2012 Wanata, Ragama
Dutch canal 2m Unidened group Steel cage to
capture
Animal captured by an unknown group and believed to be
released in Yala NP.
MDW
8 Jan 1999 Angulana sea
Moratuwa 4m By-catch
Accidentally
caught in shing
net
Released in Mugger habitat in Bundala NP. Disappeared three
days aer release.
17 Jul 2008 Pannipiya 3m Captured by villagers
out of fear Ropes and cable Released in Mugger habitat in Udawalawa NP.
11 Aug 2009 Bolgoda Lake 5.5m Villagers wanted to
kill out of fear
Using a single-
sided hook with
chicken bait
Le limb absent due to a previous incident. Released to Mugger
habitat in Bundala NP. Observed dead body aer 3 months. Death
also conrmed verbally by an ocer (anonymous) in Bundala NP.
1 Aug 2012 Egodahena,
(Ratmalana) 3m Captured due to
eang pet dogs Wire mesh cage Released in Lunugamvehera NP
20 Jan 2013 Nalluruwa,
Panadura Sea 3m Bycatch Trapped in shing
net Release area unknown
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
translocaons, resident Muggers began to aack the
introduced Saltwater Crocodiles, which were always
‘defeated’ and/or injured and tried to move to other
pools. Interesngly, half of the observed translocaons
involved Saltwater Crocodiles esmated to be over 4m
in length (Table 2), which may have been considered to
be able to deal with Muggers, but this was not the case.
As almost all pools are ulized by Muggers, the Saltwater
Crocodiles had to face the same challenges everywhere,
ending with fatal injuries or ‘disappearance’ from our
visual observaons (Table 2).
All Mugger translocaons carried out by DWC
appeared to be successful, as these animals were
released into Mugger habitats, and we did not observe
any compeon between resident and introduced
Muggers.
Since 2008, there were eight conrmed human
fatalies caused by Saltwater Crocodile aacks; in
addion, three people who ‘disappeared’ are believed
to have been taken by crocodiles. Twenty-ve people
were injured during aacks, with injuries ranging from
minor to grievous. Most aacks took place in the early
morning, late evening or at night. Most of the people
who were aacked were males aged over 30 years, and
aacks occurred while vicms were bathing or carrying
out acvies in water such as washing clothes, washing
kitchenware, collecng aquac plants, and shing.
A
B
C
© A. Godahewa
© A. Godahewa
© M.B. Madawala
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Human-crocodile conict in Sri Lanka Amarasinghe et al.
The survey indicated that 25% of the people in
crocodile habitats enter the water for daily household
acvies and occupaons, and were thus vulnerable to
aack. Females were aacked while they were washing
clothes. Most aacks in the early morning occurred
while people were washing their faces or bathing. Many
people are afraid to go to the river, and crocodile aacks
have become a common fear in their day-to-day life.
In most of the HCC areas, people are engaged in
work-related acvies associated with water (e.g.,
shing, sand mining, farming, plucking aquac owers,
prawn farming, and illegal alcohol extracon), and
so many of them face dicules to connue their
jobs, and this directly aects their daily income. In
addion, Saltwater Crocodiles have entered small
farms run by riverine communies, killing livestock
(e.g., chickens, cale, goats) and pets or guard dogs. As
Saltwater Crocodiles consume sh (e.g., Oreochromis
mossambicus, O. nilocus, Etroplus suratensis, Channa
striata, Lates sp.) there is perceived compeon for the
same food source, and so crocodiles became a common
enemy of shing communies.
We idened zones of high HCC incidence involving
Saltwater Crocodiles, which we refer to as “Crocodile
Vigilance Zones” (CVZ). We idened ve CVZs, four
of which lie within the wet zone (see Images 2–5) and
one which we propose for the dry zone. We stress
that there is a risk of increasing HCC within these zones
and the possibility of it spreading to surrounding areas
in the future unless proper management acons are
implemented.
The MMA CVZ was idened as having the highest
rates of killing crocodiles out of fear, road kills, and egg
collecng. Matara is a fast developing city and most
of the natural vegetaon around the Nilwala River
oodplains has been replaced with human habitaons,
agriculture, hotels, restaurants, roads and industrial
units. Most of the suitable habitats had consisted of
mangroves, but now all the small streams have human
encroachment. Saltwater Crocodiles generally prefer
small streams connected to the main river close to
the sea. We observed some crocodiles digging small
underground canals across the bank of the river where
most small streams had been ruined. Due to sand mining,
there has been saltwater intrusion; at mes around 5km
or more along the river. This phenomenon may result
in Saltwater Crocodiles swimming upriver, perhaps in
search of new nesng areas, as most freshwater nesng
swamps having been now replaced with saline water
and other encroachments. As a result, HCC has recently
increased in the upstream Malimbada area, which many
crocodiles use for nesng. We observed ideal nesng
habitats for Saltwater Crocodile in the Malimbada area,
which were not found anywhere downstream along the
river, even where there are healthy mangrove habitats.
Furthermore the lower plains are regularly ooded and
some crocodiles are able to enter the sea and migrate
from one river basin to another (e.g., on 19 April 2012,
a crocodile ~4.5m long was observed on the Matara
seashore, and on 6 January 2012 a crocodile ~3m long
was seen in the sea at Matara).
In the Nilwala River, where HCC has increased, we
observed many people making small canals towards their
home gardens to provide water for their culvaons;
we observed that garbage oen blocked these canals,
which contained a well grown aquac ora, including
Eichhornia crassipes (Pontederiaceae) [see Fig. 5, plate
3 in Karunarathna et al. (2010) for similar invasive
aquac plants, in the waterways of Bellanwila-Adiya
wetland]. This environment makes an ideal habitat and
nesng ground for Saltwater Crocodiles. Meat stalls
and slaughterhouses pollute the river (e.g., Malimbada
area), as do mini chicken-farms beside the river,
providing a potenal food sources for crocodiles. Many
man-eang crocodiles have been killed (using poisoned
chicken bait) by villagers around the Nilwala River, and
many unplanned translocaons were also conducted
from this area.
Bentota is a fast developing tourism zone and the
natural vegetaon around the Bentota River oodplain
is being replaced with housing, hotels, restaurants,
roads and other tourism acvies. Most of the suitable
mangrove habitats and small streams have been
replaced with hotels. We observed sea water owing
towards the land around 3km along the river, and many
ideal habitats for Saltwater Crocodiles in the Beruwala
area have been destroyed. Filling of wetlands, human
encroachments, the Beruwala disllery and its water
polluon, and tourism were idened as growing
threats for Saltwater Crocodiles and their habitats.
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
The water canals in MDW CVZ are interconnected
through the city of Colombo to Kalutara and Beruwela
in the south, also Koe marshes, Diyawanna oya,
Kirillapone, Wellawae, Dehiwela and Nedimale canals
to Bellanwila-Adiya Sanctuary, and then to Bolgoda
Lake and then to Kalu River. Furthermore the Mada Ela,
starng from Bolgoda Lake, goes as far as Erewwala-
Pannipiya, and is the reason that crocodiles are
recorded from the Pannipiya area. This zone should
have been the area of highest HCC, but it was not, due
to the high frequency of crocodile hunng (over 120
crocodiles were esmated to have been hunted in 2008–
2012) for meat, with most of the meat being sold to
tourist hotels around Colombo and Moratuwa. Bolgoda
Lake had provided good habitat for Saltwater Crocodiles,
but now it is being invaded by human selements and
many areas of the wetland have been lled. The riverine
vegetaon is destroyed and no suitable habitats remain
for crocodile nesng. That is the reason why crocodiles
are found in Colombo (on 20 February 2012 a crocodile
~3m long was observed in Colombo Dockyard Sea) and
Dehiwala (a ~2m long crocodile was seen in Dehiwala-
Wellawaa canal, and a 2m crocodile was seen on 7
February 2012 in Raanapiya Canal and Moratuwa,
which is interconnected with Bellanwila-Adiya
Sanctuary and Bolgoda Lake by canals).
This narrow canal system fullls the requirements for
Saltwater Crocodile habitat similar to the small streams
made by people in MMA CVZ. Most areas of Hamilton
Canal are well covered with many aquac oang plants
such as E. crassipes. RHW CVZ has a very high number
of meat stalls and slaughterhouses and mini chicken-
farms. Also humans have encroached to the margin of
the canal and in some areas invaded the canal as well.
Muthurajawela and other marshes in Colombo are
the main water drainage system, especially during the
southwest monsoon.
We propose KBEK CVZ, which lies within the dry
zone, as an emerging conict area, and there is a need
for immediate surveys to idenfy the core issues before
the conict becomes worse. The crocodile populaon
data and movement paerns are not well idened for
this area, except for a few preliminary surveys that are
largely unpublished and local news reports. We strongly
suggest protecng the present mangrove and other
aquac vegetaon and enriching the habitat.
Even though Saltwater Crocodiles are aorded
legal protecon in Sri Lanka, illegal harvesng of eggs
and hunng (direct and incidental) of crocodiles sll
occur. The current populaon esmate of 2000 non-
hatchlings is considered conservave, and available
data suggest that a high proporon of the populaon
comprises immature juveniles, indicave of a recovering
populaon. Despite illegal take of eggs and crocodiles,
the populaon has increased signicantly (at mean rate
of increase of 5% p.a.) since 1978, when the populaon
was esmated to be 375 non-hatchlings (Whitaker &
Whitaker 1979). Our results conrm that crocodilian
populaons have the ability to recover rapidly if harvest
rates are reduced and/or they are aorded protecon,
and habitats (including nesng habitats) remain intact.
The study also conrmed that habitats are under threat
largely due to an increasing human populaon, and the
impact of illegal harvesng in the future needs to be
addressed.
Both Muggers and Saltwater Crocodiles aack
humans (e.g., Caldico et al. 2005), and are responsible
for numerous fatalies each year (Somaweera & de Silva
2013). Crocodile aacks are common in Sri Lanka, in part
because there are high numbers of large crocodiles in
the populaon (191 crocodiles sighted were >3m long,
and were most likely males; Webb & Manolis 1989),
but mainly due to the reliance of increasing numbers
of people on water resources that contain crocodiles.
HCC is somemes aributed to overshing of one of
the crocodile’s main food sources, leading crocodiles to
hunt other prey, including humans (Uragoda 1994; Rao
1996; Anderson & Pariela 2005). This compeon can
take the form of the of live sh from shing nets and
associated damage to shing gear, and diminishing the
daily catch of shing communies (de Silva 2013).
Notwithstanding the bad image that crocodiles
receive as a result of HCC (Sanapillai et al. 2004),
our study conrmed previous reports that crocodiles
are opportuniscally killed or directly hunted for their
meat (Senanayake 1995). Whitaker & Whitaker (1977)
menoned that crocodile meat resembles shark meat in
terms of taste and texture, and is eaten by people for
its purported curave properes (de Silva 2008, 2013).
Aempts by government to migate HCC through
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Human-crocodile conict in Sri Lanka Amarasinghe et al.
the translocaon of crocodiles do not appear to have
taken into account the biology of the species, nor has the
eecveness of this strategy been assessed unl now.
Muggers are mainly concentrated in naonal parks and
man-made reservoirs in the dry zone (de Silva & Lenin
2010; de Silva 2013), and according to Sanapillai & de
Silva (2001) they are sympatric with Saltwater Crocodiles
at 25 localies, most of which are uncertain. Previous
translocaons by DWC assumed that the two species
are sympatric, but it appears that these translocaons
have modied the natural distribuons of both species
in Sri Lanka, and resulted in mortality of translocated
Saltwater Crocodiles due to social interacons with
Muggers.
Conservaon is an important naonal and
internaonal issue, and it is incumbent upon educators,
conservaon managers, legal advisors, funding agencies,
ocials and policy makers to work along with research
sciensts to ensure that inaccurate informaon does
not endanger eorts to safeguard Sri Lanka’s remaining
endangered biodiversity treasures (Bahir & Gabadage
2009), therefore management should be based on the
best available informaon.
Notwithstanding the issues associated with HCC, the
ability of Sri Lanka to maintain healthy wild populaons
of Saltwater Crocodiles will ulmately depend on
the availability of suitable habitats. Habitat loss and
destrucon, including human encroachment, are
the key factors aecng natural Saltwater Crocodile
habitats in Sri Lanka. Habitat restoraon, including the
reintroducon of mangroves on government-owned
lands, removal of unpermied human encroachments
from buer zones of river and swamp areas and reseling
of people outside of buer zones, immediate acon
to reduce saltwater intrusion into freshwater bodies,
restricng the issuing of new permits for sand mining
near river mouths (at least 10km from the river mouth),
prohibion on the dumping of garbage and farm refuse,
and cleaning up garbage and invasive aquac plants in
man-made streams leading into rivers, are acons that
can be considered within a strategy to improve and
maintain habitat quality in the short- and long-term. As
most CVZs are rapidly developing with emergent plans
for widening roads and new highways (RDA 2007), the
design of new roads should also be considered.
Diverse tourist acvies like speed-boats, tourist
boat tours and shing have led to the disappearance
of crocodiles (Gramentz 2008) in BBA CVZ. According
to Gramentz (2008), at one locaon along the Bentota
River, 39 boats were involved with sand extracon
within a 75-minute period. There were no crocodiles
recorded in the sea in front of Bentota River (Gramentz
2008), and many crocodiles have migrated to adjacent
healthier habitats, which may explain their occurrence
on the seashore of BBA CVZ, and recently in Madu Ganga
(De Silva & de Silva 2008). We recommend that speed
boats not be permied to enter at least some parts of
Dedduwa Lake (e.g., eastern side of Elpiya Road Bridge)
and the upper river. Removal of human encroachments
from the buer zone of the Dedduwa Lake area, and
liming or restricng of sand mining at least as far as the
Udugama area, are important. The banning of shing
nets being stretched right across the river and halng
of further permissions for new houses or extensions to
those already on the bank, with the implementaon of
enforcement measures, are also recommended (see
also Gramentz 2008).
We suggest implemenng a proper recycling or
disposal plan for the Karadiyana garbage dump in
MDW CVZ. In addion, cleaning the canals in Dehiwala,
Wellawaa, Colombo area, the reintroducon of
mangroves to Bolgoda Lake, and the removal of
unpermied human encroachments, meat stalls and
slaughterhouses from Dehiwala-Wellawaa canal
buer zone is very important and urgent. The current
wetland lls and unplanned developments will lead to
future ooding in Colombo, a similar scenario to that
in Jakarta, Indonesia (Caljouw et al. 2005). Devapriya
(2004) observed 20 Saltwater Crocodiles along a 2.8-
km stretch of the Dandugam Oya and 2–9 individuals in
1.7km of adjacent marsh, showing that they move from
Negombo Lagoon to adjacent river basins.
The Dutch Canal, commenced in 1802, links the
Kelani River with the main seaport of Negombo Lagoon,
and was intended to drain the Muthurajawela Marsh.
However the eect was the opposite and the high
des brought in a larger amount of saline water. This
created ideal habitats for Saltwater Crocodiles and
they bred well in these canals. This was the reason
for the increase in HCC in RHW CVZ associated with
Hamilton Canal. Also this canal network gives access to
Saltwater Crocodiles to the main channel of the Kelani
River, a major reason why some have been recorded
from Awissawella, over 50 km away inland from RHW
CVZ. Removal of unpermied human encroachments,
meat stalls and slaughterhouses from Hamilton Canal
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Human-crocodile conict in Sri Lanka Amarasinghe et al.
and maintaining a buer zone, stopping the dumping
garbage and farm refuse into the canal, and cleaning
up garbage and invasive aquac plants in the canal are
considered important and urgent acons.
Crocodiles are mostly killed by people out of fear
of aacks (Senanayake 1995), and has contributed to
the exisng bad image that crocodiles have (Sanapillai
et al. 2004). Nowadays, the public’s atude towards
crocodiles is ‘negave’, and crocodiles are simply
regarded as man-eaters, monsters and killers. The
importance of public awareness was pointed out over
35 years ago by Whitaker & Whitaker (1979), when the
frequency of HCC was low. Now HCC has increased, and
there is a need at a naonal level for increased public
educaon and awareness about crocodiles.
Eecve conservaon of Saltwater Crocodiles
will involve a diverse range of stakeholders, including
Government agencies, non-government organisaons,
business and tourism sectors, the media, the public (rural
and urban), etc., each of which may need to be involved
with or be the target of a dedicated public educaon and
awareness program. Crocodiles potenally “involve”
a suite of government jurisdicons other than DWC,
and so it is important that these other agencies (e.g.,
transport, tourism, housing, agriculture, water, shing,
police, military) are aware of crocodile management
iniaves and environmental legislaon as it pertains to
crocodiles and other wildlife. Ideally everyone should
be rowing in the same direcon!
Saltwater Crocodiles are large predators, and
humans are well within the size of prey that can be
taken. Thus, public educaon about crocodiles should
inform people about the real dangers and realies of
‘living with crocodiles’, but also convey the reasons why
crocodiles need to be conserved. Geng that message
across to the diverse range of stakeholders in Sri Lanka
will no doubt involve a suite of dierent strategies,
ranging from brochures, pamphlets, signage, media
coverage, school curriculum (Beehler 2011), T-shirts,
calendars, posters, public presentaons, tourist guides,
museum exhibits, etc. To the extent possible, the media
should present a balanced view on crocodiles, as it is an
important vehicle to assist public educaon.
Crocodile Exclusion Enclosures (CEE) have been used
eecvely in Sri Lanka, and have no doubt contributed to
reducons in HCC. However, the signicant cost involved
with the construcon and ongoing maintenance of CEEs
has constrained the Sri Lankan Government’s plans to
build more of them (CSG 2015a). A mechanism through
which local communies can facilitate and contribute to
the construcon of CEEs merits consideraon - it would
not only speed up the implementaon of CEEs in areas
of HCC, but give communies a sense of ownership
(CSG 2015a). Other iniaves, such as the provision of
water pipelines to rural communies would improve
the quality of drinking water, and reduce the reliance
on people to carry out some acvies near/in crocodile
habitats.
The eecveness of translocaon as a suitable
management opon for the migaon of HCC with
Saltwater Crocodiles within a Sri Lankan context is
unclear. Saltwater Crocodiles have a strong homing
insnct, and translocaon may result in return to the
original capture site (Webb & Manolis 1989; Walsh
& Whitehead 1993; Read et al. 2007). In northern
Australia, translocated Saltwater Crocodiles appear to
become more mobile, and two Saltwater Crocodiles
were subsequently involved in aacks on humans.
Translocaon of Saltwater Crocodiles into the wild may
thus not be an eecve strategy for managing HCC, and
may indeed exacerbate it.
We suggest that only ‘problem’ crocodiles which have
been involved in aacks or which pose a real threat to
humans and livestock be captured and translocated, and
that this be to capve facilies (see later). Government
agencies may need to develop guidelines on appropriate
capture and handling techniques. At an internaonal
level, some countries have implemented Codes of
Pracce that have been applied to both wild and capve
crocodilians (e.g., NRMCC 2009; CFAZ 2012), and which
also take into account animal welfare consideraons
(see Image 11).
We suggest that a populaon monitoring program
be developed to quanfy populaon trends in dierent
parts of the country over me, and to idenfy further
CVZs and threats to crocodiles and people. The
frequency of crocodile aacks, size structure of the
populaon, extent of nesng, etc., could provide
addional indices of the populaon that can help
guide management. DWC, in collaboraon with local
researchers, is planning a naonal survey of crocodiles,
and it is greatly appreciated that DWC will iniate such
ground level research towards proper science-based
management.
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Human-crocodile conict in Sri Lanka Amarasinghe et al.
A capve or semi-natural reserve could assist
conservaon eorts for crocodiles in Sri Lanka, as was
suggested in the 1970s by Whitaker & Whitaker (1979).
Such a reserve or facility would not only provide a site
for release of problem crocodiles captured to reduce
HCC, but could also serve as a centre of public educaon,
training (local and internaonal parcipants), capve
breeding, research and recreaon (tourism). Kirala-Kale
(Matara District), an 1800ha area, is considered to be the
most potenal locaon for a crocodile park or crocodile
reserve. Although locaons near Colombo may have
certain advantages, there are also disadvantages.
Wetlands near Colombo are interconnected with many
canals up to Chilaw Lagoon (north) and Kalu River
(south), in addion to being connected with many other
lakes and rivers. These wetlands are also situated in the
densely populated capital, so there is a risk of animals
escaping and moving to golf course pools, Diyawanna
Oya, Bera Lake, Bolgoda Lake, Bellanwila-Aththidiya
Marsh, Colombo and Hamilton Canal, and to the sea or
dock yard. And there is already a stable populaon of
crocodiles in Muthurajawela Sanctuary and Bellanwila-
Adiya. Furthermore, crocodiles are sll being killed in
the Muthurajwela area for meat and skins (Devapriya
2004), and we observed illegal crocodile egg collectors
in those areas during the course of this study.
Under current regulaons in Sri Lanka there is lile
opportunity for the development of programs based
on the sustainable use of crocodiles. Yet this concept
has assisted many countries to recover their crocodilian
populaons (CSG 2015b). A crocodile park (see above)
could provide the rst step towards a program based on
the sustainable use of Saltwater Crocodiles, through the
use of excess stock produced from breeding within the
facility. Importantly, it could also provide opportunies
for economic development for low-income communies
in the area.
It is oen local communies that must bear the
physical and economic costs of living with crocodiles
(McGregor 2005), and the economic value (consumpve
and/or non-consumpve) of crocodilians, parcularly
Saltwater Crocodiles, is the typically strongest incenve
for the public to conserve and tolerate large populaons
of them (e.g., Webb 2000; Huon & Webb 2002).
There is considerable knowledge on the management
of Saltwater Crocodiles in other countries, which may
assist Sri Lanka with its future eorts. However, every
country is dierent, and crocodile management in Sri
Lanka will need to take into account the economic,
social and cultural context of the country.
As the lead agency for crocodiles in Sri Lanka,
improving DWC’s capacity to deal with HCC and crocodile
management in general, and increasing scienc
capacity (Pethiyagoda et al. 2007; Bahir & Gabadage
2009; Amarasinghe et al. 2014) will no doubt assist the
country’s eorts to ensure the long-term conservaon
of Saltwater Crocodiles and their habitats.
The Marine Crocodile, Crocodylus porosus, from
Ponape, Eastern Caroline Islands, with notes on food habits of
crocodiles from the Palau Archipelago. Copeia 1974: 553.
A new species of
the genus Calotes (Squamata: Agamidae) from high elevaons of
the Knuckles Massif of Sri Lanka. Zootaxa 3785: 59–78.
A view
on Saltwater Crocodile (Crocodylus porosus) captured from
anthropogenic habitats in western province, Sri Lanka, pp. 258–
260. In: Crocodiles. Proceedings of the 22nd Working Meeng of
the IUCN-SSC Crocodile Specialist Group. IUCN, Gland, Switzerland.
Strategies to Migate Human-
Wildlife Conict in Mozambique. Report for the Naonal Directorate
of Forests and Wildlife, Mozambique. Food and Agriculture
Organizaon of the United Naons, Rome, Italy.
Taxonomic and scienc
inaccuracies in a consultancy report on biodiversity: a cauonary
note. Journal of Threatened Taxa 1(6): 317–322; hp://dx.doi.
org/10.11609/JoTT.o2123.317-22
Esmang the abundance of Saltwater Crocodiles,
Crocodylus porosus Schneider in dal wetlands of the N.T.: A
mark-recapture experiment to correct spotlight counts to absolute
numbers and the calibraon of helicopter and spotlight counts.
Australian Wildlife Research 13: 309–320.
Editorial: Natural History Today and Tomorrow.
Taprobanica 3: 50–51.
Home
range and movements of radio-tracked Estuarine Crocodiles
(Crocodylus porosus) within a non-dal waterhole. Wildlife
Research 35: 140–149.
Crocodile aacks in Australia. An analysis of its incidence, and
review of the pathology and management of crocodilian aacks in
general. Wilderness and Environmental Medicine 16(3): 143–159.
Flooding in Jakarta:
Towards a blue city with improved water management. Bijdragen
tot de Taal- Land- en Volkenkunde 161(4): 454–484.
Home
range ulisaon and long-range movement of estuarine crocodiles
during the breeding and nesng season. PLoS ONE 8(5): e62127.
Predicng the probability of large carnivore occurance:
a strategy to promote crocodile and human coexistance. Animal
Conservaon (early view); hp://dx.doi.org/10.1111/acv.12186
Human populaons
in the biodiversity hotspots. Nature 404: 990–992.
Codes of
Pracce. CFAZ, Harare, Zimbabwe.
Natural history of the
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
Crocodylia. pp. 337–349. In: Glasby, C.J., G.J.B. Ross & P.L. Beesley
(eds.). Fauna of Australia, Amphibia and Replia. Australian
Government Publishing Service, Canberra, Australia.
Human-Crocodile Conict;
Crocodile Exclusion Enclosures (CEEs). hp://www.iucncsg.org/
pages/Human%252dCrocodile-Conict.html.
Sustainable ulizaon.
hp://www.iucncsg.org/pages/Sustainable-Ulizaon.html.
The Tetrapod Reples of Ceylon,
Testudinates and Crocodilians. Naonal Museums of Sri Lanka,
Colombo, Sri Lanka, 412.
Preliminary survey of Saltwater Crocodiles
(Crocodylus porosus) in the Nilwala River, Sri Lanka. Crocodile
Specialist Group Newsleer 27: 10–13.
The Crocodiles of Sri Lanka (Including Archaeology,
History, Folklore, Tradional Medicine, Human-Crocodile Conict
and a Bibliography of the Literature on Crocodiles of Sri Lanka). AMP
Print Shop, Gampola, Sri Lanka.
Mugger Crocodile Crocodylus palustris.
pp. 94–98. In: Manolis, S.C. & C. Stevenson (eds.). Crocodiles. Status
Survey and Conservaon Acon Plan. Crocodile Specialist Group,
Darwin, Australia.
Record of Crocodylus porosus nest
from Sri Lanka. Crocodile Specialist Group Newsleer 27: 13–14.
A survey of the Saltwater Crocodile (Crocodylus
porosus) in the Muthurajawela urban marsh. Lyriocephalus 5: 25–
26.
Insights into the ecology and evoluonary success of crocodilians
revealed through bite-force and tooth-pressure experimentaon.
PlosOne 7: e31781.
The distribuon, abundance and threat of the
Saltwater Crocodile, Crocodylus porosus, in the Bentota Ganga, Sri
Lanka, 16pp.
Feeding across the food web: The interacon
between diet, movement and body size in estuarine crocodiles
(Crocodylus porosus). Austral Ecology (early view); hp://dx.doi.
org/10.1111/aec.12212
Legal trade snaps back: using the
experience of crocodilians to draw lessons on regulaon of the
wildlife trade, pp. 1–10. In: Crocodiles. Proceedings of the 16th
Working Meeng of the IUCN-SSC Crocodile Specialist Group. IUCN,
Gland, Switzerland.
Conservaon and management of the two
species of Sri Lankan Crocodiles (Crocodylus porosus and Crocodylus
palustris). pp. 155–165. In: Crocodiles. Proceedings of the 17th
Working Meeng of the IUCN-SSC Crocodile Specialist Group. IUCN,
Gland, Switzerland.
Current status of faunal diversity
in Bellanwila-Adiya Sanctuary, Colombo District, Sri Lanka.
Taprobanica 2: 48–63.
Movements and home ranges of radio-tracked
Crocodylus porosus in the Cambridge Gulf region of Western
Australia. Wildlife Research 31: 495–508.
Human-wildlife conict in Africa: Causes,
consequences and management strategies. Food and Agriculture
organizaon of the United Naons, Rome, Italy, 98pp.
Changes in the distribuon and
abundance of Saltwater Crocodiles (Crocodylus porosus) in the
upstream, freshwater reaches of rivers in the Northern Territory,
Australia. Wildlife Research 33: 529–538.
Long-distance movement by a Saltwater Crocodile.
Crocodile Specialist Group Newsleer 24: 18.
Crocodile crimes: people versus wildlife and the
polics of postcolonial conservaon on Lake Kariba, Zimbabwe.
Geoforum 36: 353–369.
The Naonal Red List 2012 of Sri Lanka: Conservaon
Status of the Fauna and Flora. Ministry of Environment, Colombo,
Sri Lanka: 476.
Code of Pracce for the Humane Treatment of Wild and Farmed
Australian Crocodiles. NRMMC, Canberra, Australia.
Science and biodiversity: the predicament of Sri
Lanka. Current Science 92: 426–427.
A case study of the Saltwater Crocodile Crocodylus
porosus in Muthurajawela Marsh, Sri Lanka - Consideraons for
conservaon. Journal of Bombay Natural History Society 101: 337–
343.
Nesng behaviour of the Indian crocodiles,
Gavialis gangecus, Crocodylus palustris and Crocodylus porosus,
pp. 212–216. In: Ramamurthi, R. & Geetabali (eds.). Readings in
Behaviour. Newage Internaonal Ltd, New Delhi, India.
Naonal Road Master Plan of Sri Lanka 2007–2017. Road
Development Authority, Government of Sri Lanka, Colombo, Sri
Lanka, 37pp.
Satellite tracking reveals long distance coastal travel and homing
by translocated Estuarine Crocodiles, Crocodylus porosus. PlosOne
2: e949.
The Human-Crocodile Conict in Nilwala
River, Matara (Phase 1). YZA Publicaons, Dehiwala, Sri Lanka, 86pp.
Status, distribuon and
conservaon of crocodiles in Sri Lanka. Biological Conservaon 97:
305–318.
Crocodiles of Sri Lanka. Mannar District Rehabilitaon
and Reconstrucon through Community Approach Project (www.
manrecap.com).
Human and reple conicts: impact on reples
in Sri Lanka. Lyriocephalus 2: 86.
Using tradional knowledge
to minimize human-crocodile conict in Sri Lanka, pp. 257. In:
Crocodiles. Proceedings of the 22nd Working Meeng of the IUCN-
SSC Crocodile Specialist Group. IUCN, Gland, Switzerland.
The foods and feeding habits of subadult
Crocodylus porosus Schneider in northern Australia. Australian
Wildlife Research 6: 347–359.
Wildlife Conservaon Sri Lanka. Wildlife and
Nature Protecon Society, Colombo, Sri Lanka, 162pp.
Problem crocodiles, Crocodylus
porosus, at Nhulunbuy, Northern Territory: an assessment of
relocaon as a management strategy. Wildlife Research 20: 127–
135.
Sustainable use of large reples - an introducon
to issues. pp. 413–430. In: Crocodiles. Proceedings of the 15th
Working Meeng of the IUCN-SSC Crocodile Specialist Group. IUCN,
Gland, Switzerland.
Monitoring the recovery of the Saltwater Crocodile
(Crocodylus porosus) populaon in the Northern Territory of
Australia. pp. 329–380. In: Crocodiles. Proceedings of the 9th
Working Meeng of the IUCN-SSC Crocodile Specialist Group. IUCN,
Gland, Switzerland.
CrocodilesofAustralia. Reed Books,
Frenchs Forest, Australia,
Movement and dispersal paerns
of Crocodylus porosus in some rivers of Arnhem Land, northern
Australia. Australian Wildlife Research 5: 263–283.
Regional report from CSG Vice Chairman for
South Asia. Crocodile Specialist Group Newsleer 23: 8–9.
Who’s got the biggest? Crocodile
Journal of Threatened Taxa | www.threatenedtaxa.org | 26 April 2015 | 7(5): 7111–7130
Human-crocodile conict in Sri Lanka Amarasinghe et al.
Specialist Group Newsleer 27: 26–30.
Sri Lanka crocodile survey. Loris
14: 239–241.
Preliminary crocodile survey - Sri
Lanka. Journal of Bombay Natural History Society 76: 66–85.
Accelerated human populaon growth at protected area
edges. Science 321: 123–126.
People and
Wildlife: Conict or Coexistence. Cambridge University Press, UK,
516pp.
AATA, MBM, and DMSSK conceived the concept, ideas,
plan of work and did eld work; AATA prepared the maps and manuscript;
AdS and RS contributed data and improved the manuscript; CM helped with
preparing the manuscript and nal eding.
All the authors are commission members of the Crocodile
Specialist Group (CSG), Species Survival Commission (SSC), Internaonal Union
for Conservaon of Nature (IUCN).
We thank Colin Groves, Mohamed Bahir and other
anonymous reviewers who crically reviewed this manuscript and helped
improve the quality; Special acknowledgement to the eld survey team for their
assistance in the eld. Then we would like to thank many naonal park rangers
and safari guides, safari jeep drivers in Udawalwa, Yala and Bundala Naonal
Parks for providing all the translocaon details and help to locate animals inside
naonal parks, villagers in study areas for providing informaon, and safari
jeep owners for providing transportaon to visit naonal parks and locate the
translocated crocodiles. Finally, we would like to thank members of the Young
Zoologists’ Associaon (YZA) for their support; A. Godahewa, J. Ranasinghe and
P.D. Weeraratne for photographs.
