Wildlife of Lao PDR: 1999 Status Report - IUCN

Wildlife of Lao PDR: 1999 Status Report
at Ban Hangkhon (Champasak Province) found the species
absent in July - August, but small numbers have been seen
all year at Ban Sivilai, Vientiane Province (JWKP).
• Ardea cinerea Grey Heron. Conservation Significance:
Potentially At Risk in Lao PDR. Documented Range and
Habitat: Winter visitor; north, centre, south B14 . Lakes, pools,
marshes, rivers and exceptionally paddy-fields, up to at least
800 m. Status Information: Records prior to 1997 were reviewed
by Thewlis et al. (1998). Small numbers (under a
dozen) have been widely recorded in both protected and unprotected
areas across the country, including 11 recent survey
areas (Table 11). Historically it was often described as
common and it is likely that a decline has occurred. A count
of 38 along the Mekong at Savannakhet town in late January
1997 (JAW) is the highest recent count in Lao PDR, and flocks
of at least 25 have been seen around Vientiane (T. Hansel
verbally 1998). The listing of the species as At Risk in Lao
PDR in Thewlis et al. (1998: Table 3) was a typographical
error: Appendix 2 gave the correct category.
• Ardea purpurea Purple Heron. Conservation Significance:
Potentially At Risk in Lao PDR. Documented Range and
Habitat: Mainly winter visitor, possibly local breeder; north,
centre, south B14 . Marshes, well-vegetated pools, exceptionally
paddy-fields, up to at least 800 m. Status Information:
Records prior to 1997 were reviewed by Thewlis et al. (1998).
Small numbers (under a dozen) have been widely recorded
in both protected and unprotected areas across the country,
including 11 recent survey areas (Table 11). Historically it
was often described as common and it is likely that a decline
has occurred. Juveniles were seen in Dong Khanthung
PNBCA in July 1998, raising the possibility of local breeding
(Round 1998). One was seen in a market in southern
Champasak Province (Cunningham 1998). Unpublished
records include single birds at Ban Sivilai and near Phou
Khaokhoay NBCA (JWKP). The listing of the species as At
Risk in Lao PDR in Thewlis et al. (1998: Table 3) was a
typographical error: Appendix 2 gave the correct category.
Casmerodius albus (= Egretta alba, ^K, ^T) Great Egret.
Passage migrant and winter visitor; north B9 , centre B16 , south B2 .
Paddy-fields, lakes, rivers, marshes.
Mesophoyx intermedia (= Egretta intermedia, ^K, ^T)
Intermediate Egret (= Plumed Egret, ^K). Passage migrant
and winter visitor; north B9 , centre B16 , south B2 . Paddy-fields,
lakes, marshes, river banks.
Bubulcus ibis Cattle Egret. Passage migrant and winter visitor;
north B9 , centre B16 , south B2 . Paddy-fields, pasture, marshes,
rivers; often near livestock. Records prior to 1996 were summarised
in Duckworth et al. (1998a).
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Ardeola bacchus Chinese Pond Heron. Mainly winter visitor
and passage migrant; north, centre, south B2 . No evidence
of breeding, although birds oversummer in the north (David-
Beaulieu 1944) and even perhaps the south B2 . Ponds, marshes,
river and stream banks, paddy-fields. Records prior to 1996
were summarised in Duckworth et al. (1998a).
Butorides striatus Little Heron (= Striated Heron, ^Sm).
Probably mainly winter visitor, also at least local breeder;
north B1 , centre, south B2 . Rivers, streams and pools, often in
or near forests; up to 1220 m. Breeding behaviour was seen
at Khonphapheng falls (Champasak Province) in February
1993.
• Nycticorax nycticorax Black-crowned Night Heron.
Conservation Significance: Potentially At Risk in Lao PDR.
Documented Range and Habitat: Seasonal status unclear;
north (Parr and Parr 1998), centre (historically, Robinson and
Kloss 1931), south B2 . Marshes in vicinity of stands of trees.
Status Information: The few recent records are: up to four in
the Northern Zone wetlands of Xe Pian in winter 1992-1993
(Claridge 1996, Thewlis et al. 1996); one near Ban Hangkhon
(Champasak Province; Cunningham 1998); regular sightings
of up to ten at Ban Sivilai, Vientiane Province (Parr and Parr
1998; PD); occasional birds heard over Vientiane by night
(JWKP); and singles in markets at Ban Lak (52) and (twice)
southern Champasak Province (Cunningham 1998; RJTiz).
Historically, the species was seen along the Mekong (two
localities between Vientiane and Savannakhet; Robinson and
Kloss 1931), the lower Xe Don and the Xe Kong, and at
Salavan (Engelbach 1927, 1932). It was common in
Xiangkhouang Province during September - December
(David-Beaulieu 1944). This species is vulnerable to disturbance
and persecution in the generally small groves of trees
within wetlands where it concentrates to roost and nest. Furthermore,
these are often felled, and the open areas used by
the species are often chosen for human settlement. These
negative factors doubtless limit the numbers and distribution
of the species, thus it should be considered Potentially At
Risk in Lao PDR.
Gorsachius melanolophus Malayan Night Heron. Seasonal
status unclear, presumed to breed; north B14 , centre B16 , south B14 .
Streams, rivers and forest floor in evergreen and mixed deciduous
forest, secondary growth and bamboo; probably
mainly lowland but up to at least 830 m. Records prior to
1997 were reviewed by Thewlis et al. (1998) who classified
the species as Little Known in Lao PDR. They omitted records
of calling birds from the Nam Theun Extension PNBCA in
Tizard (1996). There are post-1996 records from Nam Theun
Extension PNBCA (same area), Dong Khanthung PNBCA,
Dong Nathat Conservation Area (Savannakhet Province) and
Dong Ampham NBCA (Tobias 1997, Davidson et al. 1997,
Round 1998, Evans in prep.) indicating that the species can