Dong Nai Nature Reserve
Summary
- 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
Area | 100 km² |
Coordinates | 11.405678, 107.232591 |
Designation | Nature Reserve |
Habitat types | Subtropical/tropical moist lowland forest |
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 in 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 |
---|---|---|---|---|---|---|---|---|---|
Nomascus gabriellae | 2010 | 31 | 15 | Vinh An area, Ma Da sector, Hieu Liem sector of the reserve, approx. 200 km2 | Fixed-point triangulation, Line transects (Distance), interview survey | 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 in Dong Nai Nature Reserve
Category | Specific threats | Threat level | Quantified severity | Description | Year of threat |
---|---|---|---|---|---|
1. Residential & commercial development | Unknown | ||||
2. Agriculture & aquaculture | 2.1 Annual & perennial non-timber crops | High | Agricultural encroachment (Rawson et al. 2011). | Ongoing (2011) | |
3. Energy production & mining | Unknown | ||||
4. Transportation & service corridors | 4.1 Roads & railroads | High | 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 | Illegal hunting with guns (Rawson et al. 2011). | Ongoing (2011) | |
5.3 Logging & wood harvesting | High | Illegal logging (Rawson et al. 2011). | Ongoing (2011) | ||
6. Human intrusion & disturbance | Unknown | ||||
7. Natural system modifications | Unknown | ||||
8. Invasive & other problematic species, genes, diseases | Unknown | ||||
9. Pollution | Unknown | ||||
10. Geological Events | Absent | ||||
11. Climate change & severe weather | Unknown | ||||
12. Other options | Absent |
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 in Dong Nai Nature Reserve
Category | Specific activity | Description | Year of activity |
---|---|---|---|
1. Residential & commercial development | Not reported | ||
2. Agriculture & aquaculture | Not reported | ||
3. Energy production & mining | Not reported | ||
4. Transportation & service corridors | Not reported | ||
5. Biological resource use | Not reported | ||
6. Human intrusion & disturbance | Not reported | ||
7. Natural system modifications | Not reported | ||
8. Invasive & other problematic species, genes, diseases | Not reported | ||
9. Pollution | Not reported | ||
10. Education & Awareness | Not reported | ||
11. Habitat Protection | 11.2. Legally protect primate habitat | Ongoing (2023) | |
12. Species Management | 12.15. Reintroduce primates in groups | Two gibbons groups introduced into the reserve (Rawson et al. 2011). | 2011 |
13. Livelihood; Economic & Other Incentives | Not reported |
Challenges
Table 5. Challenges reported for Dong Nai Nature Reserve
Challenge | Source |
---|---|
Not reported |
Research activities
Documented behaviours
Table 6. Ape behaviors reported for Dong Nai Nature Reserve
Behavior | Source |
---|---|
Not reported |
External links
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 completed by: A.P.E.S. Wiki team Date: 03/04/2023