Vietnam Primate Conservation Status Review 2002 - Hoang Lien ...

3.2 HATINH LANGUR - Trachypithecus laotum hatinhensis
primates were not seen. The same month, one group of at least 4 individuals was observed near a cliff
close to basecamp 1 in the Suoi Chay valley (17 O 30.847’N / 106 O 12.776’E). At the same time and same
location several loud calls were heard in an opposite direction. In July, one group of at least 5 animals
was seen regularly in a sleeping cave at the Eo Cap site (17 O 32.638’N / 106 O 12.687’E). In August 1998,
one group of at least five members was heard and briefly observed in a sleeping cave at the Hung Lao
site (17 O 32.827’N / 106 O 12.809’E). White cheeks could be seen. Two animals with white cheeks were
seen in October 1998, in the Ta Ty area of Cha Lo Village (ca. 17 O 43’N / 105 O 47’E). A single animal was
observed in the south of Hang Ca Tuc area (17 O 35’N / 106 O 00’E) in October 1998. Head pelage was not
seen. In September and October 1998, vocalizations were heard twice to the east of Cha Noi (17 O 38’N /
106 O 05’E), once to the south of Phu Nhieu (17 O 40’N / 106 O 02’E), seven times in the Suoi Chan Loong
valley (from four different places) (17 O 37’N / 106 O 00’E), eight times in the Hang Ca Tuc area (from at
least four locations) (17 O 35’N / 106 O 00’E), once from the southern side of Mo O valley (17 O 40’N /
105 O 57’E), four times in the Suoi Mo Sang valley (from different locations on one occasion) (17 O 38’N /
105 O 55’E), and three times in the Suoi Cat valley (from seemingly three different locations on one
occasion) (17 O 43’N / 105 O 47’E).
According to nature reserve rangers, at least three groups live on the cliffs surrounding Suoi Chayriver
where they are easily encountered in the early morning. Two animals were seen by FFI staff in
this location during a short visit in June 2000 (Lormee, unpubl.). This river valley is currently being
subjected to heavy disturbance as a road is being built along the side of the river. The effect of this
development on the primates is currently unknown.
According to Timmins et al. (1999), very few sightings and vocalizations were recorded and this
suggested a reduction of the population. The same authors hypothesise that arrival and departure
from sleeping sites in the dark, as well as the probable reduction of the vocal activity (compared with
areas of comparable habitat) may reflect a change of behaviour in response to the human pressure.
Khe Net Nature Reserve, Tuyen Hoa District (QUANG BINH)
Special use forest: Nature reserve
Hatinh langur status: Occurrence confirmed, last evidence in 2000 (Le Trong Trai, pers. comm., 2000)
Tuyen Hoa District is the origin of the type and paratype described by Dao Van Tien (1970). The type,
one adult female (ZMVNU, 90) was collected in December 1942 by Chau in Xom Cuc locality. The
paratype, one male skin, was collected in 1964 in Ninh Hoa Commune during a survey organised by
the State Committee for Science and Technology (museum and collector unknown).
During their survey for Hatinh langur in 1995 and 1996, Pham Nhat et al. (1996a) could not find any
information about this species in the area.
However, Le Trong Trai (pers. comm., 2000) observed three langurs in June 2000 in the limestone
forest of Kim Lu area, Kim Hoa Commune (17 O 56,917’N / 105 O 57,937’E). The animals were too far
away to actually see whether the head pelage was consistent with hatinhensis or with the black
morph “ebenus”. This could be the first record of the Hatinh langur in the area. Local hunters
reported that 20 to 30 animals still inhabited the area.
Locations where Hatinh langurs are believed to be extinct
Ba Ren and Truong Son, Bo Trach District (QUANG BINH)
No information was collected by Pham Nhat et al. (1996a) in the area during a survey with a special emphasis
on Hatinh langur in 1995 and 1996. The species is believed to be locally extinct (Pham Nhat et al., 1996a).
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