Summary

Loading map...

Yellow-cheeked gibbons (Nomascus gabriellae) are present in Dong Nai Nature Reserve.
A minimum of 17 groups were estimated to inhabit the site in 2010.
The gibbon population trend is unknown.
The site has a total size of 100,303 hectares (including 32,400 ha of Tri An Reservoir).
Key threats to gibbons are hunting, logging, roads and agricultural encroachment.
Conservation activities include a trial for establishing another gibbon population in the reserve.

Site characteristics

Dong Nai Nature Reserve is located in the Dong Nai Province, Vietnam. Dong Nai Nature Reserve is one of the most important conservation areas in Vietnam as the site contains a high biodiversity richness. The landscape of the nature reserve is dominated by lowland semi evergreen forest, and the elevation ranges from 100 to 340 m above sea level. The reserve is one of the most important strategic watershed forests of the Dong Nai River and Tri An hydropower dam which provides drinking water for the second most populated and industrial area of Vietnam (Nguyen Manh Ha et al. 2010).

Table 1. Basic site information for Dong Nai Nature Reserve

Species	'Nomascus gabriellae
Area	100 km²
Coordinates	Lat: 11.405678 , Lon: 107.232591
Type of site	Protected area (Nature Reserve)
Habitat types	Subtropical/tropical moist lowland forest
Type of governance

IUCN habitat categories Site designations

Ape status

Surveys in 2010 recorded 15 groups of N. gabriellae with at least 31 individuals, including 13 males, 10 females and 8 juveniles, identified by their distinctive calls (Nguyen Manh Ha et al. 2010). In total, 69 survey days were spent surveying 34 listening posts and 34 transects. Gibbons have been extirpated in some parts of the reserve, probably due to intensive hunting and logging over the past few decades. Most gibbons persist in areas close to Cat Tien National Park, and this is probably due to better habitat and protection spill-over from the park (Nguyen Manh Ha et al. 2010).

Table 2. Ape population estimates reported for Dong Nai Nature Reserve

Species	Year	Total number indiv. (95% CI)	Total number groups (95% CI)	Density [groups/km²] (95% CI)	Area	Method	Source	Comments	A.P.E.S. database ID	NA	NA
Nomascus gabriellae	2010			15	31	Vinh An area, Ma Da sector, Hieu Liem sector of the reserve, approx. 200 km2	Fixed point triangulation, Line transects, Interviews		Nguyen Manh Ha et al. 2010	Minimum of 17 groups and 31 individuals.

Threats

Hunting and logging are the key threats to N. gabriellae in this reserve; gibbons are still often sourced for the wildlife trade from this location, with an estimated minimum of five animals traded per year (Rawson et al. 2011). Forest quality is poor in areas previously logged. Several roads bisect the site and agricultural encroachment is occurring along these (Nguyen Manh Ha et al. 2010).

Table 3. Threats to apes reported for Dong Nai Nature Reserve

Category	Specific threats	Threat level	Description	Year of threat
10 Geological events		Absent
12 Other threat		Absent
2 Agriculture & aquaculture	2.1 Annual & perennial non-timber crops	High (more than 70% of population affected)	Agricultural encroachment (Rawson et al. 2011).	Ongoing (2011)
4 Transportation & service corridors	4.1 Roads & railroads	High (more than 70% of population affected)	Several roads bisect the site, driving further habitat destruction (Nguyen Manh Ha et al. 2010).	Ongoing (2010)
5 Biological resource use	5.1 Hunting & collecting terrestrial animals	High (more than 70% of population affected)	Illegal hunting with guns (Rawson et al. 2011).	Ongoing (2011)
5 Biological resource use	5.3 Logging & wood harvesting	High (more than 70% of population affected)	Illegal logging (Rawson et al. 2011).	Ongoing (2011)
1 Residential & commercial development		Unknown
3 Energy production & mining		Unknown
6 Human intrusions & disturbance		Unknown
7 Natural system modifications		Unknown
8 Invasive & other problematic species, genes & diseases		Unknown
9 Pollution		Unknown
11 Climate change & severe weather		Unknown

IUCN Threats list

Conservation activities

In August 2011, two groups of gibbons were released into this reserve and monitored to assess whether more gibbons could be introduced here from the Dao Tien Rescue Centre with the aim of establishing another gibbon population (Rawson et al. 2011).

Table 4. Conservation activities reported for Dong Nai Nature Reserve

Category	Specific activity	Description	Implementing organization(s)	Year of activity
5 Protection & restoration	5.2 Legally protect ape habitat			Ongoing (2023)
6 Species management	6.8 Reintroduction of apes (captively-bred or rehabilitated indviduals)	Two gibbons groups introduced into the reserve (Rawson et al. 2011).		2011

Conservation activities list (Junker et al. 2017)

Challenges

Table 5. Challenges reported for Dong Nai Nature Reserve

Challenges	Specific challenges	Source	Year(s)
	Not reported

Enablers

Table 6. Enablers reported for Dong Nai Nature Reserve

Enablers	Specific enablers	Source	Year(s)
1 Site management
2 Resources and capacity
3 Engaged community
4 Institutional support
5 Ecological context
6 Safety and stability

Research activities

Documented behaviours

Table 7. Behaviours documented for Dong Nai Nature Reserve

Behavior	Source
Not reported

Exposure to climate change impacts

External links

Relevant datasets

References

Nguyen Manh Ha, Nguyen Hoang Hao, Tran Duc Dung, Nguyen Manh Diep, Pham Van Nong, Report of yellow-cheeked crested gibbon (Nomascus gabriellae) survey in Dong Nai Nature Reserve, Dong Nai province, Vietnam. Fauna & Flora International/Conservation International, Hanoi, Vietnam.

Rawson, B. M, Insua-Cao, P., Nguyen Manh Ha, Van Ngoc Thinh, Hoang Minh Duc, Mahood, S., Geissmann, T. and Roos, C. (2011). The Conservation Status of Gibbons in Vietnam. Fauna & Flora International/Conservation International, Hanoi, Vietnam.

Page created by: A.P.E.S. Wiki team Date: NA

Dong Nai Nature Reserve

Contents