Status, distribution, and ecology of the siamese crocodile (crocodylus siamensis) in central lao PDR master thesis in forest science

MINISTRY OF EDUCATIONAND TRAINING

MINISTRY OF AGRICULTURE AND RURAL
DEVELOPMENT

VIETNAM NATIONAL UNIVERSITY OF FORESTRY
--------------------

Paseun SOUVANNASY

Status, Distribution, and Ecology of the Siamese Crocodile
(Crocodylus siamensis) in Central Lao PDR

MASTER THESIS IN FOREST SCIENCE

Hanoi, 2018


MINISTRY OF EDUCATIONAND TRAINING

MINISTRY OF AGRICULTURE AND RURAL
DEVELOPMENT

VIETNAM NATIONAL UNIVERSITY OF FORESTRY
--------------------

Paseun SOUVANNASY

Status, Distribution, and Ecology of the Siamese Crocodile
(Crocodylus siamensis) in Central Lao PDR

Major: Forest Science
Code: 8620201

MASTER THESIS IN FOREST SCIENCE

Academic advisor: Dr. Luu Quang Vinh
Prof. Dr. Thomas Ziegler

Hanoi, 2018


ABSTRACT
The Siamese Crocodile (Crocodylus siamensis) is the most threatened species
of crocodians and already to become extinct in the wild from many regions,
essentially a scientifically-based call to action for preventing the extinction of wild
species around the world. Current species was listed in the IUCN Red List status of
Critically Endangered. Natural distributions of the species extant populations are in
Cambodia, Indonesia, Lao PDR, Thailand and Viet Nam.
Natural distribution of the species in Laos Surveys confirmed previous
reports that many local populations are now extirpated. Extant populations are in the
Xe Champhone, Xe Banghiang, Xe Bangfai and Xe Xangxoy river systems
(Savannakhet Province), Xe Pian - Xe Khampho river systems (Attapu Province),
Xe Don river (Salavan Province) and Phou Khao khouay National Protected Area
(Bolikhamxay Province).
The propose of this research is to investigate the presence of the Siamese
Crocodile population, estimate the population size/structure, investigate the ecology
of this species, predict the potential distribution and identify potentially suitable
habitats, identify threats to the population and provide recommendations for habitat
protection and species conservation in Khammuane and Savannakhet provinces.
At least 2 to 4 individuals by field survey observation and interview with the

local people of Ka Cham village, Peo Ban Hang and Peo Song Hong Lakes found
only one individual by field survey observation and from interview the local people
of Soc Village estimated 1 individual occurred in these lakes.
Kout Mark Peo the minimum number is 1+ individual (adult), trails, one nest
unfinished on the floating mat of grass, in Nong Paen Lake the minimum number
are 11+ individuals (Juvenile), 3+ individuals (adult), nests with eggs, Nong Kond
Phai the minimum number is 1+ individual (adult) and one resting site and at least
1+ individual living in the Xe Hack Lake can be estimated.

I


The content of prey remains in feces as soil particle, reptiles, vegetation, fish
scale, mammals. The main threats to the species in study sites are habitat loss,
drought, hunting animal, disturbance by humans and pets, fishing, flood, eaten by
animal hunter. The highest priority for conservation is Nong Paen and Kout Mark
Peo Lakes, followed by which is Nong Bua Ta Lake and Peo Bang Hang and Peo
Song Hong lakes. The lowest site for conservation is Xe Hack and Nong Kond Pai
Lakes.

II


Table of Contents
ABSTRACT ..................................................................................................................... I
List of figures ................................................................................................................ IV
List of tables .................................................................................................................. VI
1. INTRODUCTION ..................................................................................................... 1
1.1 Background .............................................................................................................. 1
1.2. Goal .......................................................................................................................... 2

1.3. Objectives ................................................................................................................. 2
1.4. Hypotheses ............................................................................................................... 3
2. LITERATURE REVIEW ......................................................................................... 3
2.1 Taxonomy and natural conservation of the species .................................................. 3
2.2. Ecology of the Siamese Crocodile ........................................................................... 5
2.3. Population Status of the Siamese Crocodile ............................................................ 8
2.4. Conservation Actions ............................................................................................. 13
2.5. Legal regulations to protect the Aquatic and wildlife in Laos ............................... 15
3. METHODS .............................................................................................................. 17
3.1. Study sites .............................................................................................................. 17
3.2. Data collection ....................................................................................................... 19
4. RESULTS................................................................................................................. 25
4.1. Distribution of the Siamese Crocodile in the study sites ....................................... 25
4.2. Habitats of the Siamese Crocodile ......................................................................... 27
4.3. Population size of the Siamese Crocodile .............................................................. 30
4.4. Population structure of the species ......................................................................... 39
4.6. Suitability habitat ................................................................................................... 42
4.7. Threats to Crocodile Population ............................................................................ 44
5. DISCUSSION .......................................................................................................... 47
6. CONCLUSION ........................................................................................................ 52
7. ACKNOWLEDGEMENT ..................................................................................... 54
8. REFERRENCES ..................................................................................................... 55
APPENDIX ................................................................................................................... 61

III


List of figures
Figure 1. The current distribution of the Siamese Crocodile
Figure 2. Dead crocodile has killed by local people near Tan Soum Village

5
10

(Lao WCS)
Figure 3. Battery fishing in Phai Jiew reservoir

12

Figure 4. Paddy rice and drainage Chanel for water pump to support rice
production in the dry season around the Xe Hack Lake

13

Figure 5. Map of the study sites

18

Figure 6. Diagram of crocodile Head Length (HL) and Total Length (TL)
measurements.

20

Figure 7. Measuring the crocodile tracks

22

Figure 8. Analyzing on the content of the food items

23

Figure 9. The distribution of the Siamese Crocodile in Lao PDR

26

Figure 10: Habitat of the Siamese Crocodile in Nong Bua Ta Lake

27

Figure 11: Habitat of the Siamese Crocodile in Peo Ban Hang (Khun Khe lake
System)

28

Figure 12: Habitat of the Siamese Crocodile in Peo Song Hong (Khun Khe
lake System).

28

Figure 13: Habitat of the Siamese Crocodiles in Kout Mark Peo Lake

29

Figure 14: Habitat of the Siamese Crocodiles in Nong Paen Lake

29

Figure 15: Habitat of the Siamese Crocodiles in Xe Hack Lake

30

Figure 16: Habitat of the Siamese Crocodiles in Nong Kon Phai Lake

30

Figure 17: Big feces of the species found on grass at Nong Buata Lake

31

Figure 18: Small feces of the species found on grass at Nong Buata Lake

31

Figure 19. Estimation of the Crocodile individuals by interviewed hunters

32

Figure 20. Estimation of the Crocodile individuals by interviewed fishermen

33

Figure 21. The Siamese Crocodile in Peo Ban Hang

34

IV


Figure 22. Resting site of the Siamese Crocodile (sun basking),

35

Figure 23. Trail of the Siamese Crocodile on floating mat of grass in Kout
Mark Peo Lake

35

Figure 24. Unfinished nest on floating mat of grass in Kout Mark Peo Lake

35

Figure 25. Estimation of the Crocodile individuals by interviewed in Kout
Mark Peo Lake

36

Figure 26. A juvenile crocodile at night time in Nong Paen lake

37

Figure 27. Crocodile resting site (sun basking) near a nest in Nong Paen lake

37

Figure28. Crocodile nest with eggs in Nong Paen Lake

37

Figure 29. Estimation of the Crocodile individuals by interviewed in Nong
Paen Lake, Tan Soum Village

38

Figure 30. The resting site of the Siamese Crocodile at Nong Kond Phai Lake

39

Figure 31. The Siamese Crocodile trail at the Xe Hack Lake

39

Figure 32. Fecal sample after identified in the laboratory (Savannakhet
Province)

41

Figure 33. Fecal sample after identified in the laboratory (Khammuane
Province)

41

Figure 34. Suitability habitat of the Siamese Crocodile in Lao PDR.

43

Figure 35. Estimate the Percent of threats to the Siamese Crocodile population
in Nong Bua Ta Lake

44

Figure 36. Estimate the Percent of threats to the Siamese Crocodile in Peo
Ban Hang and Peo Song Hong Lake

45

Figure 37: Estimate the Percent of threats to the Siamese Crocodile
population in Kout Mark Peo, Nong Paen, Xe Hack and Nong Kon Phai lakes

V

46


List of tables
Table1. Contents of Seven Crocodile fecal samples in Laos

6

Table 2. Estimated size of total wild population of C. siamensis in
40

Khammuane and Savannakhet Provinces
Table 3. Contents of four C. siamensis fecal samples from Khammuane and
Savannakhet provinces

41

Table 4. Criteria for conservation priorities

49

Table 5. Crocodile observations night time survey at Nong Paen Lake
A=adult; J=juvenile

61

Table 6. Summary of day research in Khammuane Province

62

Table 7. Summary of day research in Khammuane Province

63

Table 8. Environmental data variables were used in the model. (Bold
variables were used in the final model prediction.)

64

Table 9. Datasheet

65

VI


1. INTRODUCTION
1.1 Background

Biodiversity loss is one of the most severe crises of the world, because the

current rate of species extinction is estimated to be between 1,000 and 10,000 times
higher than the natural extinction rate (when humans were not around) (Böhm et al.
2013). Major causes of this crisis are related to habitat loss and degradation,
unsustainable harvest, introduced invasive species, environmental pollution,
disease, and global climate change (Gibbons et al. 2000).
The Siamese crocodile, Crocodylus siamensis, is one of the most endangered
of the world‟s 23 species of crocodilian, a medium size species with a total length
less than 3.5 m (Smith 1919) and adult females are normally smaller than 2.7 m
(Simpon, 2006). This species historically occurred over mainland of Southeast Asia
as well as parts of Indonesia. Its current distribution is greatly diminished and
fragmented. Extant populations are in Cambodia, Indonesia, Lao PDR, Thailand
and Vietnam; wild populations in Vietnam were possibly extirpated. Surveys over
the past two decades have failed to detect crocodiles in sites they were reported to
occur (Platt and Tri 2000, Stuart et al. 2002) except one site, Ha Lam Lake (Phu
Yen Province), where at least two individuals were present in 2005 (Nguyen et al.
2005). As a result of fewer than 1,000 mature wild individuals in natural
distribution, due mainly to habitat loss and over-hunting, the species was listed on
Appendix I of CITES, and classified as 'Critically Endangered' on the IUCN Red
List (2018).
In Lao PDR, the species was widely distributed until the early 1900s. Much
of the country is mountainous and suitable for crocodile habitats (lakes, ponds
swamps and marshes) are mainly restricted to the lowland areas along the Mekong
in southern and central Laos (Bezuijen et al. 2013). Small breeding populations still
persist, but a severe decline in its distribution and now the species is rare or locally
extinct at many sites (Bezuijen et al. 2013). The species was recorded at 13 sites in

1


6 river systems, with at least 36 individuals (1-11 per site) (Bezuijen et al. 2013). At

all sites, crocodile densities and recruitment rates were extremely low. Currently,
fewer than 300 adult individuals may be present in the wild and the species also was
listed “at Risk” as the highest nationally threat ranking in Lao PDR (Bezuijen et al.
2006). However, Bezuijen et al. 2006 stated that most wetlands in Laos remain
unsurveyed for crocodiles and it seems likely that other C. siamensis localities will
be documented.
In Khammuane Province, (Bezuijen et al. 2013) reported three negative
records of the species from Hin Nam No and Nakay-Nam Theun National Protected
Areas and two unconfirmed records from the Nam Hin Boun river system
(tributaries in Phou Hin Boun National Protected Area, previously “Limestone
National Protected Area” in Khammuane Province: one record from in between
1960-1979, and one in between 1980-1999 (Bezuijen et al. 2006). According to the
latter author no further record could be made in Khammuane in the past 16 years.
However, (Ziegler et al. 2015) discovered an overlooked population of the species
in Soc village, Bualapha district, near Hin Nam No National Protected Area.
However, the knowledge on the distribution, population status and ecology of the
species is virtually unknown (Ziegler et al. 2015).Therefore, further research is
essential for proposing proper species conservation measures.

1.2. Goal
The goal of this study is to evaluate the population status and ecology of the
Siamese Crocodile in Khammuane and Savannakhet provinces, in order to provide
baseline information for conservation measures.

1.3. Objectives
Specific objectives of this study are:
-

To identify the actual distribution of C. siamensis in Khammuane and
Savannakhet provinces;

2


-

To estimate the population size/structure of C. siamensis in Khammuane
and Savannakhet provinces;

-

To investigate the ecology of this species, including habitat preference,
diet ecology;

-

To predict the potential distribution and identify potentially suitable
habitats of C. siamensis in Laos by applying of Species Distribution
Models.

-

To identify threats to the population;

-

To provide recommendations for habitat protection and species
conservation in Khammuane and Savannakhet provinces.

1.4. Hypotheses
In the present the populations of Siamese Crocodile were quite to extinction

in Southeast Asia, the importance of the Siamese Crocodile is one cause to study
and indentify the distribution, estimate population size and structure, ecology,
suitability habitat, threats to the Siamese crocodile species and recommendation for
the species conservation measures.

2. LITERATURE REVIEW
2.1 Taxonomy and natural conservation of the species
Taxonomy of the Siamese Crocodile: The scientific name is Crocodylus
siamensis Schneider, 1801. English name is Siamese Crocodile. It belongs to
Animalia Kingdom, Chordata Phylum, Reptilia Class, Crocodilia Oder and
Crocodilidae family ().
This species are the most advanced surviving reptiles; all crocodilians have a
similar body shape, with a head held horizontally in front of the body, four legs
which project from the sides, heavy scales which function as armor, and a heavy
muscular tail. Their front feet have five separate toes and rear feet have four
partially-webbed toes. The dominant of this species is swim higher in the water,

3


control access to mates, choice nesting sites, food, basking sites, and living space
(Crocodile Management Association of Thailand, 2010).
Current and Historical Distribution of the Species
Current distribution of The Siamese Crocodile (Crocodylus siamensis) is
greatly diminished and fragmented. Extant populations are in Cambodia, Indonesia,
Lao PDR, Thailand, and Viet Nam. In Cambodia, it was recorded in 35 sites of 21
river systems of 11 provinces in the southwest and northeast Cambodia (Daltry and
Chheang, 2000), occurred in the Mahakam River system of Indonesia, there is no
other information to suggest that C. siamensis occurred in Malaysia, one record of
crocodiles and eggs, from the Mekong River (Garnier, 1996), a small number of

scattered localities in Kaen Kra chan National Park (Southwestern), Pang Sida
National Park and Khao Ang Rue Nai Wildlife Sanctuary (eastern), Phu Khieo
Wildlife Sanctuary (northeastern) of

Thailand (Temsiripong, 2003). A single

reintroduced population is at Cat Tien National Park (Polet, 2004) and in Laos was
occurred from nine river systems in five provinces as in the central and southern
parts (Bezuijen et al. 2013).

Thirty-five wetlands (25 floodplain lakes, two reservoirs, and sections of
eight rivers) were surveyed in 11 river systems in the three provinces of Attapu (N
= 9 sites), Salavan (N = 2), and Savannakhet Province (N = 24). Twenty-one sites
were in Central Laos and 14 were in South Laos. Elevations of the sites ranged
between 60 and 280 m. (mean 135 m). In Attapu Province the sites comprised two
lakes and two rivers on alluvial forested floodplains in the Xe Pian National
Protected Area (NPA) and five lakes outside the NPA termed the „Bung
Pulon‟complex (Bezuijen et al. 2007). In Salavan Province, both sites (the Xe Don
River and a pond, Nong Boua) were in a river valley among cultivated land and
secondary forest 300 m apart from a small village. In Savannakhet Province, 21
sites were on floodplains of the Xe Champhone and Xe Xangxoy rivers (the largest
tributaries of the Xe Banghiang); and three sites were along the Xe Bangfai river.
4


Nineteen of these sites were vegetated oxbow lakes, and five sites were sections of
five rivers that were slow-flowing and rocky or sandy. Most sites in Savannakhet
Province were in cultivated landscapes among paddy fields, shrub land, and small
patches of secondary forest.

Figure 1. The historical distribution of the Siamese Crocodile (in yellow)

2.2. Ecology of the Siamese Crocodile
2.2.1. Habitat
Almost the Siamese Crocodiles were occurred in the Southeast Asia, these
species almost lived in freshwater bodies, including lakes, swamps and slowmoving rivers, especially the deep-water sections in Cambodia (Han et al. 2015). In
Laos, historically occurred in a wide range of permanent wetland, rivers, lakes and
ponds, These habitats almost the same such as covered by water vegetation, scrub
forest on the floating mat of grasses, around the bank were covered by forest, dense

5


bamboo etc. if compare with my study sites is almost the same with (Bezuijen et
al. 2006).

2.2.2. Diet
According to (Han et al.2015; Daltry et al. 2003), 291 fecal samples were
analyzed and recorded, a content of the feces included fishes (30.9%), reptiles
(29.6%), invertebrates (detected in 11.5% of feces, including ants, beetles,
scorpions and crabs), mammals (4.9%) and birds (3.0%). The reptiles and fishes
were identified at least (88, 1%) of the reptiles were snakes (26, 1%) of the all feces
examined.
Table 1. Contents of Seven Crocodile fecal samples in Laos (Bezuijen et al.
2010).
Sites
Bung Pulone Lake

Dung size (mm)

Contents

85 x 37

Mammal hair; fish scale (sp. Ascales transparent, thin, 3-5 mm
diameter)

Bung Pulone Lake

95 x 45

Mammal hair; fish scale (sp. A);
snake

scales;

insect

chitin

fragments; plant matter.
Bung Pulone Lake

125 x 30

Mammal hair; fish scale (sp. A);
snake

scales;

insect

chitin

fragments; plant matter.
Bung Pulone lake

175 x 40

Mammal hair; fish scale (sp. A+B
scale brown, opaque, thick, 6mm
diameter); plant matter

Bung Pulone lake

150 x 45

Mammal

hair;

bone

(incisor,

vertebrae, other fragment); fish
scale (sp. B); snake scales, insect
chitin fragments; plant matter.

6

Kout

Mark

Peo

180 x 43

Mammal hair; snake scales; insect

Lake

chitin fragments; plant matter

Xe LatN yai Lake

130 x 40

Plant matter

2.2.3. Reintroduction
Reintroduction has been considered in some countries as a potential method
for conservation of C. siamensis. It has been conducted in Vietnam (Polet, 2006), in
Thailand (IUCN-CSG Working Group unpublished minutes 2004; Temsiripong,
2001), been suggested for some sites in Cambodia (Jelden et al. 2005). Many C.
siamensis exist in farms in Thailand, Cambodia, and Viet Nam, and a significant
resource for potential reintroduction efforts (Ross, 1998), event represents the first
successfully induced natural breeding of the Philippine crocodile in Europe and

many breeding success in relatively short period of time and after having had
chance to enable to natural breeding in capacity for the management of Crocodile
conservation breeding in Philippine (Ziegler et al. 2015). In Lao PDR, a potential
reintroduction source of C. siamensis is the Kuen Zoo Village in Vientiane, which
houses the only known large captive collection of C. siamensis in Lao PDR
(Phothitay et al. 2005; Thorbjarnarson, 2003). The Cologne Zoo has been
collaborating with different agencies and institutions in Laos and Vietnam to
undertake genetic screening of both wild and captive C. siamensis. To identify purebred

individuals

for

conservation

breeding

programs,

including

future

release/restocking projects in protected areas in Laos and Vietnam (Nguyen et al.
2018).
Any reintroduction program in Lao PDR would need to consider the following:
 Is reintroduction really needed, or should conservation efforts first focus on
protecting
the remaining crocodiles and their habitats.
 Are the crocodiles to be introduced 100% genetically “pure” C. siamensis or

are they

7


hybrids with other species? Genetic testing would be essential to confirm that only
distinct C. siamensis, not hybrids, are used.
 How do local communities feel about reintroduction? Are crocodiles
protected by community beliefs at the site? It is possible that in some sites,
introduced crocodiles would be caught and sold for the skin trade
 Is there enough financial and technical support to monitor the status of
crocodiles that
have been reintroduced? Any reintroduction program would need to include
monitoring of the individual crocodiles, to assess the success and any problems of
the project.
 Adherence to IUCN reintroduction guidelines, particularly the need to ensure
that health animals (with no diseases or parasites) are released into the wild.

Normally the Siamese Crocodile mate and lay eggs during the dry season
(April and May). The number of eggs per nest is at least 20 to 50 eggs but it
depends on the age of the crocodile, the nests made by dry leaves, grasses on
ground or on the floating grass mats were depend on the habitat area , when finished
the egg lay the female will guard. Hatching occurs after around 80 days, after that
the female will open the nest and carry the hatchings to the water (“Siamese
Crocodile | Utah’s Hogle Zoo,” n.d.). And the females were observed re-using the
same nesting sites year after year (Han et al. 2015).
2.3. Population Status of the Siamese Crocodile
2.3.1. Population Size
The largest Siamese Crocodile population confirmed 23 localities contain at
least 162 individuals in Cambodia (Siamese Crocodile Report, 2004), any single site

is 55-60 individuals in Cambodia (Daltry& Starr et al. 2010), in Thailand has
recorded several individuals, in Vietnam may has been extirpated from the wild but
reintroduction based on 60 individuals released between 2001 to 2004 at Cat Tien

8


National Park had an estimated population at least 100 to 150 individual, Indonesia
has been estimated fewer than 30 individuals occurred at Mesangat Lake in East
Kalimantan by survey in 2010 to 2011 and in Laos were confirm at least 13 wild
crocodiles (6+ adults, 2 juveniles, 5+ hatchlings), eight nests, various feces, and
trails from small and large crocodiles, as well as seven captive crocodiles (2 adults,
2 juveniles, 3 hatchlings). The sightings confirmed the presence at least 36
crocodiles (22+ adults, 6 juveniles, 8+ hatchlings) in these sites; the minimum
number of confirmed crocodiles was 1–11 individuals per site (Bezuijen et al. 2006)
and in 2015 overlooked population, and at the same time the rediscovery a
Crocodile of ca 3.5 meters in Soc village, Bualapha District, Khammuane Province
(Ziegler et al. 2015).

2.3.2. The Status of the Siamese Crocodile
The status of the Siamese Crocodile is listed on Appendix I of CITES, and is
listed as 'Critically Endangered' on the IUCN Red List (2018) with declining
population trend. These have revealed a severely depleted and fragmented
population, with C. siamensis confirmed from 35 sites on 21 river systems across
11 provinces in Cambodia (Simpon, 2006). In Laos the population was reduced and
fragmented in the middle and southern of the Laos as Savannakhet, Salavan,
Champasack, and Khammuane provinces, now this species has been classified at
Risk by reported of Bezuijen et al. (2013). There is no other information to suggest
that C. siamensis occurred in Malaysia, the extant populations are in a small number
of scattered localities in central and western Thailand (Kreetiyutanont, 1993,

Ratanakorn et al. 1994, Platt et al.2002). In Viet Nam wild populations possibly
extirpated, a single reintroduced population is at Ka Tien National Park (Polet et al.
2004).

9


2.3.3. Threats to the species
Hunting
The demand for live crocodiles is not restricted to farms and markets in
Cambodia, Thailand and China. According to a press release on 19 August 2002,
adult Siamese crocodiles weighing 40-50kg fetch as much as $1,000 in Vietnam
while in Cambodia the price fletch up to $1800 (Han et al. 2015) Smaller crocodiles
sell for $200, with juveniles fetching $50. Killing out of fear or retribution was
rarely a problem; local people in some area respected the Crocodile and generally
did not regard them as the danger, killing of wild crocodiles for skins is also rare. In
Laos hunting occurred in the mid-20th century, principally for skin harvest and
supply live crocodiles to crocodile farms, appears to be the principle cause of these
declines and in the central Laos, sine 1960s sold 5000-6000 kip or about 5 $ at that
time per “thuk”(a unit of 10 cm of belly skin equivalent to the width of a hand), the
residents along the Xe Champhone river reported that the skins and live crocodiles
were previously sold to traders from Thailand (Bezuijen et al. 2013) and in 3
December 2011 one female Crocodile is killed by Lao Hoa Kham Villager near Tan
Soum Village (Steven G. Platt 2012).

Figure 2. Dead crocodile has killed by local people near Tan Soum Village, 05
December 2011. Photo: Lao WCS.
10

Illegal collection of eggs and crocodiles
The Illegal capture of wild crocodiles for supply to farms is an ongoing
threat, as well as incidental capture/drowning in fishing nets and traps in Cambodia
(Simpon, 2010). The illegal crocodile trade in Lao PDR appears to have been
widespread in southern provinces until at least the early 1990s, with sale of live
crocodiles or skins to Thailand or Cambodia, or transport of crocodiles from
Cambodia to Thailand via southern Lao PDR.

Habitat loss and degradation
In southeast Asia, such as in Cambodia the Siamese Crocodile has been lost
due to rice growing, illegal logging and forest clearance but document has been
mentioned that widespread modification and pollution of natural wetlands
throughout lowland Cambodia. Marshes have been turned into rice paddy, ponds
have been choked with water hyacinths and other invasive alien species and
riverside vegetation has been cleared for farmland and settlement (Smith, 2001).The
current threats to crocodile habitats were measured at 26 sites within 25 wetlands in
southern part of Laos were Clearance and drainage, burning for cultivation land
around the lakes, swamps, ponds and other reasons (Bezuijen et al. 2006).

Fishing
The most destructive fishing methods in Cambodia, such as electro fishing,
spear fishing and the use of explosives or poisons, are prohibited by Fisheries and
Environment law but still widely practiced, causing indiscriminate killing of aquatic
wildlife and severe declines in fish stocks (Han et al. 2015). Produces over 400,000
tons of freshwater fish per year, the fourth largest harvest in the world were China,
India and Bangladesh (Van Zalinge, 2002). Fish accounts for 75% of the animal
protein consumption, and provides direct revenue and employment to 45%
Cambodians (Van Zalinge et al. 2000). In Laos, fishing was a key subsistence
activity for most people and includes intensive use of monofilament gillnets,

11


explosives, poisons, electro fishing, pumping out site the wetlands and overuse of
fence traps in the raining season as breeding fishes season, which made to fish
population decreased (Bezuijen et al. 2006).

Figure 3. Battery fishing in Phai Jiew reservoir, 23 June 2018. Photo: Paseun
Souvannasy.

Human disturbance
The extent of seven disturbance variables (historic hunting, clearance,
drainage, burning, livestock grazing, fishing and weed invasion) recorded at 24
wetlands in 2005 showed highly disturbed landscape in those four sites. Those sites
appeared to be similar to most other sites, except for the presence of high remnant
vegetation cover (60-100%) around or within the wetland, compared with mean
20% cover at 24 sites. This suggests that crocodile recruitment may persist in the
presence of some disturbance, as long as vegetation cover is retained around or
within the wetland (Bezuijen et al. 2006). The human disturbance very big problem
in Laos, now the local people, they encroached the habitat of the Siamese Crocodile

12


Such as clearance around the swamps, lakes and ponds into agriculture land and
fishing off the local also have problem to Crocodile population directly and it‟s one
season to make the crocodiles move to other sites, and loss the habitat finally.

Figure 4. Paddy rice and drainage Chanel for water pump to support rice production
in the dry season around the Xe Hack Lake, 29 June 2018. Photo: Paseun

Souvannasy

2.4. Conservation Actions
Cambodia: Focus of enforcement patrols and community-based conservation
management, which have demonstrated success in reducing poaching (Daltry et al.
2006; Simpson and Simpson et al. 2006). Additional community sanctuaries are
planned in the northeast. The Cambodian Government and conservation groups
have initiated a re-introduction plan to bolster wild stocks and maintain viable
populations; this is the only programme to exclusively focus on conserving Siamese
crocodiles in the wild.
Indonesia: Follow-up surveys and conservation initiatives are planned for the
Danau Mesangat area in the Mahakam River system in late 2009 and 2010 (Dacey,
2008).

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Laos: At least three factors are key to C. siamensis conservation in Laos
there are community based conservation approaches outside of the national
protected areas system, habitat-level management of a range of permanent and
seasonal wetlands (rivers, lakes and ponds), and protection of confirmed breeding
sites. A new crocodile conservation project was initiated, which included
preparation of a crocodile management plan for Savannakhet Province e (Cox and
Somvongsa 2008). This is a further management plan for crocodiles in Laos.
(Simpson and Bezuijen, 2010).The Wildlife Conservation Society has been working
with the Laos government on a new programme to save this critically endangered
crocodile and its wetland habitat. In August 2011, a press release announced the
successful hatching of a clutch of 20 Siamese crocodiles. These eggs were then
incubated at the Lao Zoo. This project represents a new effort by WCS to conserve
the biodiversity and habitat of Laos‟ Province, now it still has some problems

because after the project has been completed, nobody monitor in these sites and it‟s
beget the habitat encroach of the Crocodile, including burned the bamboo forest for
agriculture land, collected bamboo shoot inside the protected areas, and also illegal
fishing as battery fishing, they used a lot of nets to trap the fishes in raining season
(fish breeding season), for my understanding should provide some fund to support
the local communities to continues the monitoring especially in Champhone
District, Savannakhet Province, Lao PDR.
Thailand: A re-introduction project has been initiated by the Royal Thai
Forest Service and the Crocodile Management Association of Thailand with 20
crocodiles being released in a pilot project in Pang Sida National Park in 2005 and
2006 (Temsiripong 2001, 2006), and

in 2010 the Crocodile Management

Association of Thailand has been organized the project in the two national parks
and one was wildlife sanctuary as Pang Sida National Park, Khao Ang Rue Nai
National Park, and Phu Khieo wildlife Sanctuary(Crocodile Management
Association of Thailand, 2010).

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Vietnam: A re-introduction of 60 adults/sub-adults to Bau Sau Lake in Cat
Tien National Park was carried out in 2001-2004 (Polet, 2002; Murphy et al. 2004).

2.5. Legal regulations to protect the Aquatic and wildlife in Laos
The regulation (Aquatic and wildlife law 2007) to protect the wildlife and
Aquatic in Laos has mentioned as below:

Article 24. Hunting Wildlife and Aquatic

Hunting and catching wildlife and aquatic shall be practiced as follow:
1. The prohibition category of wildlife and aquatic are defined in the first (I)
category list is tally not permit for hunting except the following necessary
cases such as: for educational research and breeding purposes, but shall
require the permission from the government. If the animals capture caused
damage to the individual‟s properties or an organization‟s properties, the
captor shall report the incident to the district authority or municipality to
consider and resolve the issue. If an animal is destroying and endangering
to human life, such an issue shall be resolved immediately, hereby report
to the concerned authorities.
2. Wildlife and aquatic are defined on the category (II) list incur restrictions
and prohibitions on hunting, except selected animals species in some areas
and some seasons as customary hunt or catch will be allowed by using the
tools and equipment not cause any harm to the population of animals. The
catching or hunting of animals for business purposes can be caught only
with the permission from the Ministry of Agriculture and Forestry.
3. Wildlife and aquatic are defined in the common or general category (III)
list are allowable for hunting in only specified seasons and by using tools
and equipment‟s not harmful to the animals‟ population. The catching and
hunting animals for business purposes require the permission from the
agriculture and forestry division of the province or Capital city.

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Article 52. General prohibition
To prohibit individuals, local organizations and international organizations
are in the Lao PDR taking any of the following actions:
1. Taking wildlife and aquatic life in the prohibition category list including
carcasses, parts and organs of such animals from its habitats or to have it

in the possession.
2. Any torment on wildlife and aquatic.
3. Illegal catching, hunting, trading and possession of the wildlife and/or
aquatic life without the required permission.
4. Catching aquatic and hunting wildlife in the conservation zones, and in
breeding season, or when pregnant or with small calves.
5. To produce, import, sell or use tools or weapons which lead to increased
depletion of wildlife and aquatic including: All hunting guns and rifles,
explosive devices, chemicals, poisons, electricity, rays or sound wave, etc.
6. Devastation of wildlife conservation zones, reservoir conservation areas,
habitats and feeding zones of wildlife and aquatic directly or indirectly
such as: Clearing, resettlements, slush and burn, felling, over prescribed
using of pesticide or herbicides, and other activities which violated the
laws and regulations.
7. Occupation resettlement shifted, changed or damaged the boundary signs
of reservoir conservation areas, animal species conservation zones and
habitats.
8. Husbandry wildlife and aquatic for business purposes in city and
community which
leading to pollute and contaminate the environment.
9. Import, export, re-export, transshipment, or transit of wildlife and aquatic
life with infected diseases, or endangering to animal‟s health, or import
animals in a period of restriction or prohibition confined to the permission
granted and laws and regulations.

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10. To bribe to staff and officers, and to fake documents and or fake stamps.
11. Threatening, pulling back or obstructing the civil servants in carrying out

their tasks dealing with wildlife and aquatic.
12. Any other actions that are in violation of laws and regulations on wildlife
and aquatic.

3. METHODS
3.1. Study sites
This research focused in two sites because those sites are strategy zones of
the government for aquatic – wildlife conservation areas, both of these sites are very
important as in Khammuane Province is a national protected area and Savannakhet
Province is a Ramsar site including the national Siamese Crocodile conservation
area as follows:
 The first site is in the Ka Cham, and Soc Villages, Bualapha District, about
100 kilometers from Khammuane Province. The villages are located along
the Xe Bangfai river (17° 29' 4.2'' N - 105° 35' 33'' E), with elevations
reaching from 80 to 180 m above sea level. The wetland areas are located
near the Hin Nam No National Protected Area.
 The second site is in the Tan Soum Village, Champhone District, about 70
kilometers from Savanakhet Province(16° 20' 54" N - 105° 10' 52" E), with
elevations reaching from 130 to 180 m above sea level, this village is located
in wetland(Ramsar site).

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