Dakrong Nature Reserve
Asia > Vietnam > Dakrong Nature Reserve
Summary
- Northern yellow-cheeked crested gibbons (Nomascus annamensis) are present in Dakrong Nature Reserve.
- The population size is unknown.
- The gibbon population trend is unknown.
- The site has a total size of 376.18 km².
- Key threats to gibbons are illegal logging and exploitation of non-timber forest products.
- Conservation activities are not documented.
Site characteristics
Located in Quang Tri Province, in the center part of the Annamite Mountain Range, Vietnam, the Dakrong Nature Reserve was established in 2001(Vu & Doherty 2021). Approximately half the area is covered by rich and medium evergreen forest; the rest is covered by poor, regrowth forest, plantations, or bare land. The terrain of the reserve consists of low and medium hills, with the highest peak reaching 1410 m above sea level (Vu & Doherty 2021).
Table 1. Basic site information for Dakrong Nature Reserve
| Area | 376.18 km² |
| Coordinates | 16.625414 N, 106.893379 E |
| Designation | Nature Reserve |
| Habitat types | Subtropical/tropical moist lowland forest, Subtropical/Tropical Heavily Degraded Former Forest |
IUCN habitat categories Site designations
Ape status
The northern yellow-cheeked crested gibbon only occurs in the Central Annamite mountain range along the borders of Vietnam and Laos, and Vietnam and Cambodia. No complete survey for the species has been conducted (Vu & Doherty 2021). A survey was conducted in the reserve in 2019 using passive acoustic monitoring. Gibbon calls were detected in 39 out of 95 recording sites (Vu & Doherty 2021). Assuming a 600 m detection distance, the model-averaged occurrence probability for the nature reserve was 0.44 (SE=0.06). The area of rich and medium evergreen forests within a km of the recording posts was the most important predictor of occurrence (positively correlated). Detection probability was estimated to be 0.52 (SE=0.04) per day (Vu & Doherty 2021).
Table 2. Ape population estimates in Dakrong 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 annamensis | 2019 | Dakrong Nature Reserve | Passive acoustic monitoring | Vu & Doherty 2021 |
Threats
Most hunters active in the region are thought to come from other provinces, more than 100 km away from the reserve. Similar to other studies, a 2021 study showed a higher occupancy of gibbons in high vs low quality forest (Vu & Doherty 2021). Generally, northern yellow‐cheeked gibbon populations have dramatically decreased in Vietnam due to hunting, habitat loss, and the wildlife trade (Vu & Doherty 2021). The site has been selectively logged in the past, and timber and NTFP exploitation still occurs in the reserve. In addition, local communities live in villages near the nature reserve boundary (Vu & Doherty 2021).
Table 3. Threats to apes in Dakrong Nature Reserve
| Category | Specific threats | Threat level | Quantified severity | Description | Year of threat |
|---|---|---|---|---|---|
| 1. Residential & commercial development | Unknown | ||||
| 2. Agriculture & aquaculture | Unknown | ||||
| 3. Energy production & mining | Unknown | ||||
| 4. Transportation & service corridors | Unknown | ||||
| 5. Biological resource use | 5.1 Hunting & collecting terrestrial animals | Present, but threat severity unknown | Signs of wildlife hunting and trappings are recorded in the nature reserve (Vu & Doherty 2021). | Ongoing (2021) | |
| 5.2 Gathering terrestrial plants | Present, but threat severity unknown | Illegal exploitation of non-timber forest products (Vu & Doherty 2021). | Ongoing (2021) | ||
| 5.3 Logging & wood harvesting | Present, but threat severity unknown | Illegal timber exploitation, in the past and ongoing (Vu & Doherty 2021). | Ongoing (2021) | ||
| 6. Human intrusion & disturbance | Unknown | ||||
| 7. Natural system modifications | Unknown | ||||
| 8. Invasive & other problematic species, genes, diseases | Unknown | ||||
| 9. Pollution | 9.2 Industrial & military effluents | Medium | Forest cover has been reduced by the spraying of chemical defoliants during the Second Indochina War (BirdLife International 2021). | 1955-1975 | |
| 10. Geological Events | Absent | ||||
| 11. Climate change & severe weather | Unknown | ||||
| 12. Other options | Absent |
Conservation activities
Table 4. Conservation activities in Dakrong 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 | Not reported | ||
| 12. Species Management | Not reported | ||
| 13. Livelihood; Economic & Other Incentives | Not reported |
Conservation activities list (Junker et al. 2017)
Challenges
Table 5. Challenges reported for Dakrong Nature Reserve
| Challenge | Source |
|---|---|
| Not reported |
Research activities
Documented behaviours
Table 6. Ape behaviors reported for Dakrong Nature Reserve
| Behavior | Source |
|---|---|
| Not reported |
External links
Relevant datasets
References
Vu, T. T., & Doherty, P. F. (2021). Using bioacoustics to monitor gibbons. Biodiversity and Conservation, 30(4), 1189-1198. https://link.springer.com/article/10.1007/s10531-021-02139-1
Page completed by: A.P.E.S. Wiki team Date: 28/01/2022