Wildlife of Lao PDR: 1999 Status Report - IUCN

Wildlife of Lao PDR: 1999 Status Report
fresh faeces, slides and tracks were observed (Davenport et
al. 1997). Wild Siamese Crocodiles have been nearly extirpated
from Thailand (Cox et al. 1998) and Vietnam (MRCS/
UNDP 1998), and their continued existence is questionable
in Malaysia and Indonesia (MRCS/UNDP 1998). Lao
populations of Siamese Crocodiles are of extreme global
importance, as the last viable populations are thought to exist
there and in Cambodia (MRCS/UNDP 1998). The supposed
viability of populations in Lao PDR has not been examined,
but remains in doubt based on the drastic declines
reported by local people (Salter 1993b) and by the paucity of
recent field records. Field surveys specifically to assess the
distribution, status, and threats to Siamese Crocodiles in Lao
PDR have not been undertaken and are urgently needed.
Salter (1993b) detailed occurrences of crocodiles based
on interviews with local people throughout the country. The
results of these and more recent interviews are summarised
in Table 8. However, some reports of the presence of crocodiles
may be over-optimistic, as in 1995 the majority of local
people in Xe Bang-Nouan NBCA initially reported the species
to be frequently encountered, but after laboured interviewing
it was learned that perhaps only a few people had
actually seen a crocodile in the last ten years (RJTim).
The above records are assumed with confidence to be
C. siamensis. Although some authors report that Estuarine
Crocodile C. porosus occurs throughout South-east Asia
(Levy 1991, Cox et al. 1998), it is doubted that the records in
Lao PDR refer to this species. Crocodylus porosus is a large
and aggressive species that today seems limited on mainland
South-east Asia to coastal estuaries, as is the case in Cambodia
(MRCS/UNDP 1998).
Three main threats have been identified for crocodiles in
Lao PDR:
Harvest for skin trade and the collection of eggs and live
animals for stocking crocodile farms in Thailand (Baird
1993) and Cambodia (MRCS/UNDP 1998). Some local
people seem to hunt crocodiles opportunistically, while
others target the species with set lines and perhaps night
spotlighting (Claridge 1996). A young crocodile that was
believed to come from the Xe Kaman river was reportedly
confiscated from traders in 1993 in Saysetha District,
Attapu Province (Baird 1995a). A 2.5 m crocodile
was reported to be captured alive (date unreported) near
Savannakhet but died before it was sold to Thai traders,
although the skin was later smuggled to Mukdahan, Thailand
(Baird 1993). A skull and 2 m skin that appeared in
late 1997 in the Vientiane morning market was reported
by the vendor to have come from the Nam Ngum river
downstream of the Nam Ngum Reservoir (RJTiz). Local
people in Ban Nam Leuk (Phou Khaokhoay NBCA) reported
catching and eating a crocodile from the upper
Nam Leuk river in 1995 (JWKP). A resident of Xe Bang-
64
Nouan NBCA reported shooting a crocodile in 1993 for
commercial purposes, but the carcase was abandoned
before a buyer could be found (Timmins and Bleisch
1995, RJTim).
Habitat destruction through drainage and clearing of wetlands
for conversion to agricultural lands, intensification of the
use of remaining wetlands exposing any remaining crocodiles
to higher risk of opportunistic killing, and the construction
of hydropower reservoirs which flood breeding
sites and allow hunters with boats easier access to
crocodiles (Claridge 1996).
Hybridisation of Siamese Crocodiles in commercial crocodile
farms threatens the genetic integrity of captive stock
and diminishes chances for supplementing wild
populations in the future with reintroduced captive animals.
Large numbers of Siamese Crocodiles are bred
successfully in Thai and Cambodian crocodile farms, and
to a lesser extent in Vietnam, Indonesia, and some European
and American zoos (MRCS/UNDP 1998). Therefore,
this species could be a candidate for re-introductions
should suitable habitat persist and hunting be controlled.
No captive breeding populations are known in
Lao PDR at the present, although a large group is maintained
at the Ban Keun Zoo. Two of these animals were
reported by zoo staff to have originated from southern
Lao PDR, while the rest originated from Thai crocodile
farms (RJTim). Unfortunately, in the 1960s many crocodile
farms in Thailand began to hybridise Siamese Crocodile
with Estuarine Crocodile for improved skin quality
and growth rates (Cox et al. 1998), and at least one farm
in Vietnam has begun hybridising with the exotic Cuban
Crocodile C. rhombifer (MRCS/UNDP 1998). Other
farms may begin hybridising with Cuban Crocodiles as
well, since six females from a consignment of 100 animals
sent to Vietnam several years ago are now residing
at a commercial crocodile farm in Siem Reap, Cambodia
(MRCS/UNDP 1998).
THREATS TO AMPHIBIANS AND REPTILES
The greatest threat to herpetofauna in Lao PDR is harvest,
for domestic consumption, for internal trade and for
unregulated export. Many amphibians and reptiles are eaten
for food, and many are collected for their perceived value in
Lao (Baird 1995b), Vietnamese (Jenkins 1995, Le Dien Duc
and Broad 1995), and Chinese (Zhao and Adler 1993) traditional
medicine. Turtles, monitors, other lizards, snakes and
crocodiles are all used in traditional medicines. For example,
Baird (1995b) reported uses in Lao traditional medicine
for crocodile gall-bladders, head skin and teeth, for turtle
scales, shells and gall-bladders, for python bone, oil and gallbladders,
for monitor oil, for Water Dragon bones and chin
meat, for pit viper bones, and for cobra and King Cobra bones.
However, since many species are consumed not only for
curing specific ailments but also because of general health