Lac Télé Community Reserve

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Summary

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• Central chimpanzees (Pan troglodytes troglodytes) & western lowland gorillas (Gorilla gorilla gorilla) are present in Lac Télé Community Reserve.
• It has been estimated that 3,207 (CI: 1,699-6,052) gorillas and 85 (CI: 21-351) chimpanzees occur in the site.
• The chimpanzee and gorilla population trends are decreasing.
• The site has a total size of 4,380 km².
• Key threats to great apes are hunting and habitat loss due to expected increase in road construction.
• Conservation activities have focused on monitoring with SMART, anti-poaching patrols, and providing alternative forms of income and protein to reduce the bushmeat trade.

© Guido Trevillini, WCS

Site characteristics

Lac Télé Community Reserve (LTCR) is located in the northeastern Republic of the Congo. Consisting of 70% wetland, Lac Télé Community Reserve is one of the world's largest swamp-forest (WCS).The site is located between the Sangha and Oubangui rivers. The Reserve comprises four main terrestrial ecosystems: (i) permanently flooded forests (also called swamp forests; 50% of the size of the Reserve), (ii) seasonally flooded forests (24%), (iii) terra firma forests (9%), and (iv) seasonally flooded savannas (17%). The Reserve is bisected by the Likouala-aux-Herbes River (a tributary of the Sangha river) and the savannas are found along the river, extending 2-3 km from its banks. There are two rainy seasons: a minor one from May to July, and a major one from September to November (Romani & Ossere 2025a). During the latter, approx. 90% of the LTCR is flooded.
In the centre of the reserve lies an area of firm land, which is an important habitat for gorillas (WCS). The reserve supports one of the densest populations of western lowland gorillas, and it is also home to chimpanzees, elephants, buffaloes, duikers, and hippopotamuses. In total, the primate community includes 11 species, 2 apes and 9 cercopithecidae species (Romani pers. comm. 2025).
The reserve is populated by local communities (approximately 20,000 people live in the reserve, mainly on its borders; WCS; Ramsar). These communities heavily depend on the reserve's natural resources for fish, agriculture, construction materials, canoes, and medicines (WCS; Ramsar).
The reserve was designated a Ramsar site in 1998. In 2017, the Lac Tumba Transboundary Ramsar Site was established, which includes Lac Télé and Grands Affluents in Congo, as well as Ngiri-Tumba-Maindombe in the Democratic Republic of Congo (Ramsar). The Reserve is also a Key Biodiversity Area (KBA) and an Important Bird Area (IBA).

Table 1. Basic site information for Lac Télé Community Reserve

Species	Pan troglodytes troglodytes, Gorilla gorilla gorilla
Area	4,380 km²
Coordinates	Lat: 1.316971 , Lon: 17.223215
Type of site	Non-protected area (Community Forest)
Habitat types	Subtropical/tropical swamp forest, Subtropical/tropical moist lowland forest, Wetlands (lakes, rivers, streams, bogs, marshes), Shrubland, Grassland
Type of governance

Types of sites Governance types Habitat types

© Guido Trevillini, WCS

Ape status

Earlier studies (1990s) found diverse groups of gorillas in the swamps, and no accurate estimations of chimpanzee abundance or densities have been carried out. Surveys conducted between 2002 and 2023 have provided a picture of the status of great apes- western lowland gorillas (Gorilla gorilla gorilla) and central chimpanzees (Pan troglodytes troglodytes)- in the region. These studies, relying on line transect distance sampling and covering various zones such as the main Reserve, the Batanga, and the Tanga reveal both temporal and spatial variations in ape densities.
The first comprehensive estimate, carried out in 2002 by Poulsen & Clark (2004), showed relatively high densities, particularly for gorillas, with an estimated 2.9 individuals/km² and a total population of over 13,000 gorillas in the Reserve. Chimpanzees were less abundant, with densities around 0.7 individuals/km². Subsequent surveys confirmed these trends but also highlighted fluctuations over time.
In 2006, Stokes et al. (2010) observed a decrease in both species, especially chimpanzees, whose density dropped to 0.13 individuals/km², while gorillas maintained moderate levels (2.27 individuals/km²). These differences may reflect changes in survey methodology, nest decay assumptions, or actual population dynamics. Notably, in Batanga in 2007, gorilla density estimates spiked to over 5 individuals/km², suggesting localized areas of high abundance. However, these numbers declined in 2009 and again in 2012, pointing to either a real population decline or variability in detection.
The 2011 survey by Maisels et al. (2012) showed contrasting situations across regions: high gorilla densities (4.3 ind./km²) in Lac Télé north, but much lower densities (0.5 ind./km²) in the southern zones. Chimpanzees remained scarce in most surveys, with densities rarely exceeding 0.2 individuals/km², and sometimes too low for reliable estimation.
By 2017, densities in the Reserve had decreased further, with gorillas estimated at 1.6 individuals/km² and chimpanzees at 0.16 individuals/km² (Brncic et al. 2018). The most recent surveys in 2023 (Estienne et al. 2025) confirmed this declining trend, particularly for chimpanzees, whose densities reached a low of 0.02 individuals/km² in the Reserve and 0.08 individuals/km² in Batanga. Gorillas also showed reduced densities compared to earlier surveys, with values around 0.76-0.91 individuals/km² depending on the site.
In summary, over the last two decades, gorillas have consistently been more abundant than chimpanzees, but both species show signs of population decline in many areas. The highest densities have historically been recorded in swamp and mixed forests, but recent data suggest growing conservation concern, especially for chimpanzees, whose nest encounters have become extremely rare. These findings underscore the importance of continued monitoring and the need to understand the drivers of change in great ape populations across the region (Romani pers. comm. 2025).

Table 2. Ape population estimates reported for Lac Télé Community Reserve

Species	Year	Occurrence	Encounter or vistation rate (nests/km; ind/day)	Density estimate [ind./ km²] (95% CI)	Abundance estimate (95% CI)	Survey area	Sampling method	Analytical framework	Source	Comments	A.P.E.S. database ID
Gorilla gorilla gorilla	1989-1990		1.43	1.20		Mboukou zone	Line transects	Distance sampling with adopted decay time	Fay et al. 1990, Fay & Agnagna 1992	Nest decay rates from Tutin and Fernandez (1984).
Gorilla gorilla gorilla	1993		2.85	2.93		Botala, Bossela, Liouesso zones	Line transects	Distance sampling with adopted decay time	Blake et al. 1995	Nest decay rates from Tutin and Fernandez (1984).
Gorilla gorilla gorilla	2002		3.07	2.9 (0.3-5.4)	13,221 (7,054-25,597)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Poulsen & Clark 2004	Highest densities in swamp forest and terra firma mixed forest. Nest decay rates from Tutin et al. (1995).
Pan troglodytes troglodytes	2002		2.07	0.7 (0.1-1.3)	3,189 (1,741-5,814)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Poulsen & Clark 2004	Nest decay rates from Tutin et al. (1995).
Pan troglodytes troglodytes & Gorilla gorilla gorilla	2002		5.15	3.6 (2.0-6.2)	16,514 (9,171-28,049)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Poulsen & Clark 2004	Nest decay rates from Tutin et al. (1995).
Gorilla gorilla gorilla	2006		4.26	2.27 (1.66-3.11)	8,919 (6,514-12,211)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Stokes et al. 2010	Decay rates of nests from Morgan et al. (2006).
Pan troglodytes troglodytes	2006		0.66	0.13 (0.07-0.26)	509 (257-1,007)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Stokes et al. 2010	Decay rates of nests from Morgan et al. (2006).
Pan troglodytes troglodytes & Gorilla gorilla gorilla	2006		4.92	2.08 (1.38-3.12)		Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Stokes et al. 2010	Decay rates of nests from Morgan et al. (2006).
Gorilla gorilla gorilla	2007		3.33	5.25 (2.70-10.19)	5,402 (2,778-10,486)	Batanga (1,029 km²)	Line transects	Distance sampling with adopted decay time	Rainey et al. 2009	Decay rates of nests from Morgan et al. (2006).
Pan troglodytes troglodytes & Gorilla gorilla gorilla	2007		1.97	6.81 (3.93-11.84)	7,647 (4,044-12,183)	Batanga (1,029 km²)	Line transects	Distance sampling with adopted decay time	Rainey et al. 2009	Decay rates of nests from Morgan et al. (2006).
Gorilla gorilla gorilla	2009		2.21	1.50 (0.82-2.76)	3,368 (1,841-6,108)	Tanga (2,246 km²)	Line transects	Distance sampling with adopted decay time	Malanda et al. 2009	Decay rates of nests from Morgan et al. (2006).
Pan troglodytes troglodytes	2009		0.01			Tanga (2,246 km²)	Line transects	Distance sampling with adopted decay time	Malanda et al. 2009	Too few chimpanzee nests to calculate density.
Pan troglodytes troglodytes & Gorilla gorilla gorilla	2009		2.36	1.63 (0.97-2.51)	3,660 (2,178-5,637)	Tanga (2,246 km²)	Line transects	Distance sampling with adopted decay time	Malanda et al. 2009	Decay rates of nests from Morgan et al. (2006).
Gorilla gorilla gorilla	2011		0.80	0.5 (0.3-1.1)	1,758 (845-3,658)	Bailly south and Lac Tele south (3,299 km²)	Line transects	Distance sampling with adopted decay time	Maisels et al. 2012	Decay rates of nests from Sanz et al. (2007).
Pan troglodytes troglodytes	2011		0.55	0.14 (0.05-0.37)	455 (171-1,208)	Bailly south and Lac Tele south (3,299 km²)	Line transects	Distance sampling with adopted decay time	Maisels et al. 2012	Decay rates of nests from Sanz et al. (2007).
Pan troglodytes troglodytes & Gorilla gorilla gorilla	2011		1.16	0.62 (0.34-1.13)	2,046 (1,128-3,712)	Bailly south and Lac Tele south (3,299 km²)	Line transects	Distance sampling with adopted decay time	Maisels et al. 2012	Decay rates of nests from Sanz et al. (2007).
Gorilla gorilla gorilla	2011		6.44	4.3 (2.2-8.4)	11,859 (6,096-23,072)	Lac Tele north (2,755 km²)	Line transects	Distance sampling with adopted decay time	Maisels et al. 2012	Decay rates of nests from Sanz et al. (2007).
Pan troglodytes troglodytes	2011		0.67	0.17 (0.07-0.39)	463 (202-1,064)	Lac Tele north (2,755 km²)	Line transects	Distance sampling with adopted decay time	Maisels et al. 2012	Decay rates of nests from Sanz et al. (2007).
Pan troglodytes troglodytes & Gorilla gorilla gorilla	2011		7.09	3.79 (2.06-6.97)	10,437 (5,672-19,204)	Lac Tele north (2,755 km²)	Line transects	Distance sampling with adopted decay time	Maisels et al. 2012	Decay rates of nests from Sanz et al. (2007).
Gorilla gorilla gorilla	2012			2.92 (1.7-5.02)	3,009 (1,749-5,175)	Batanga (1,029 km²)	Line transects	Distance sampling with adopted decay time	Iyenguet et al. 2012	Decay rates of nests from Morgan et al. (2006).
Pan troglodytes troglodytes & Gorilla gorilla gorilla	2012			3.03 (1.78-5.17)	3,124 (1,835-5,318)	Batanga (1,029 km²)	Line transects	Distance sampling with adopted decay time	Iyenguet et al. 2012	Decay rates of nests from Morgan et al. (2006). Too few chimpanzee nests to calculate density.
Gorilla gorilla gorilla	2017		4.99	1.60 (0.83-3.11)	6,761 (3,487-13,109)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Brncic et al. 2018	Decay rates of nests from Morgan et al. (2016).
Pan troglodytes troglodytes	2017		0.79	0.16 (0.07-0.34)	669 (309-1,448)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Brncic et al. 2018	Decay rates of nests from Morgan et al. (2016).
Pan troglodytes troglodytes & Gorilla gorilla gorilla	2017		5.78	1.93 (1.03-3.63)	8,158 (4,351-15,297)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Brncic et al. 2018	Decay rates of nests from Morgan et al. (2016).
Gorilla gorilla gorilla	2023			0.76 (0.40-1.44)	3,207 (1,699 - 6,052)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Estienne et al. 2025	Decay rates of nests from Morgan et al. (2016).
Pan troglodytes troglodytes	2023			0.02 (0.01-0.08)	85 (21-351)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Estienne et al. 2025	Decay rates of nests from Morgan et al. (2016).
Pan troglodytes troglodytes & Gorilla gorilla gorilla	2023			0.80 (0.43-1.48)	3,356 (1,807-6,235)	Lac Télé Community Reserve (4,380 km²)	Line transects	Distance sampling with adopted decay time	Estienne et al. 2025	Decay rates of nests from Morgan et al. (2016).
Gorilla gorilla gorilla	2023			0.91 (0.50-1.67)	2,073 (1,133-3,790)	Batanga (2,276 km²)	Line transects	Distance sampling with adopted decay time	Estienne et al. 2025	Decay rates of nests from Morgan et al. (2016).
Pan troglodytes troglodytes	2023			0.08 (0.02-0.36)	170 (35-818)	Batanga (2,276 km²)	Line transects	Distance sampling with adopted decay time	Estienne et al. 2025	Decay rates of nests from Morgan et al. (2016).
Pan troglodytes troglodytes & Gorilla gorilla gorilla	2023			1.05 (0.60-1.85)	2,394 (1,364-4,204)	Batanga (2,276 km²)	Line transects	Distance sampling with adopted decay time	Estienne et al. 2025	Decay rates of nests from Morgan et al. (2016).

Sampling methods Analytical frameworks

Threats

As a result of the civil war occurring in the country in the 90s, many war guns are still present in the country. Poaching is widespread in the country, and the laws and regulations of legal hunting do not follow direct scientific criteria.
In the Reserve there are currently no major threats to ape populations. Subsistence hunting by local population is permitted, However monitoring by reserve staff of hunting catches as well as seizure of illegal game at road check point have shown that apes are present but at very low level in the carcasses (1 chimpanzee carcasses out of 2,182 carcasses in five villages monitored in 2023 - Bondeko et al., 2024 ; 7,5 kg of smoked gorilla seized over 4 years out of a total of 5,921 kg seized at road check point - Romani et al., 2025).
The proposed road between Bene (north LTCR) and Epena (east LTCR) would cut the northern area into two pieces, leading to fragmentation and poaching inside an area that is nowadays considered as virgin flooded forest (Trivellini, G. pers. comm. 2022). For this road, authorities have already "posed the first stone"; a trail was manually opened by villagers in early 2024; since that date, no work has been undertaken and the trail is gradually being closed by the vegetation.

Table 3. Threats to apes reported for Lac Télé Community Reserve

Category	Specific threats	Threat level	Description	Year of threat
1 Residential & commercial development	1.1 Residential areas	Low (up to 30% of population affected)	20 000 people live in and around the réserve. Limited land clearing for housing purpose (Brugiere pers. comm. 2025).	Ongoing (2025)
11 Climate change & severe weather	11.2 Droughts	Present (unknown severity)	Apparent increase in climatic variability translates into increasingly very dry years. Savanna fires (which occur every year) destroy gallery forests along the Likouala river and tend to spread into forests. If frequency of dry years increases, this may change the whole ecology of the area and impact ape populations (Brugiere pers. comm. 2025).	Ongoing (2025)
2 Agriculture & aquaculture	2.1.2 Small-holder farming	Medium (30-70% of population affected)	Subsistence agriculture around villages based on slash & burn system (Brugiere pers. comm. 2025).	Ongoing (2025)
5 Biological resource use	5.1 Hunting & collecting terrestrial animals	Medium (30-70% of population affected)	Mammal species hunted for commercial bushmeat markets, not only locally, but also in urban areas further away, e.g., in Kinshasa (WCS). Hunting gorillas in the area seems to be opportunistic (Romani et al., 2025), but some cases of poachers targeting gorillas are known.	Ongoing (2025)
5 Biological resource use	5.3 Logging & wood harvesting	Low (up to 30% of population affected)	Deforestation concentrated along the rivers and in terra firma forests. Trees are logged mainly for firewood collection and slash-and-burn agriculture. Although at the moment is it small-scale, the threat is expected to increase as road networks expand in the area (WCS).	Ongoing (2025)
4 Transportation & service corridors	4.1 Roads & railroads	High (more than 70% of population affected)	A road project between Epene and Bene is foreseen and proposed by the State. Future, but public authorities already organised events to publicly announce the project will be done. The road would cut the northern area of the reserve, increasing the access to nowadays inaccessible flooded forest and potentially fragmenting the humid environment (if the road will be built on a stripe of terra firma; Trivellini, G. pers. comm. 2022).	Unknown

Threats

Conservation activities

The reserve is managed by the Ministry of Forest Economy (MEF) in partnership with WCS Congo. The reserve employs 65 staff (2024 figure) (3 MEF, 62 WCS) in five departments: law enforcement, community development, research & monitoring, logistics, human resources & finance. Annual budget is 1,5 USD M (2024) (100% provided by WCS). Law enfocement team comprises 19 staff (2 MEF; 17 WCS). Law enforcement patrols are permanently deployed in the field (2024 figures: 71 patrols and 3,105 man-days of rangers in the field; 9 poachers arrested; 1,161 kg of bushmeat seized). Community-based conservation is constantly implemented, focusing on sustainable use of natural resources (fish), improving living conditions (school, health, etc.) and developing income generating activities (honey, cocoa). Research and ecological biomonitoring in place for several years focusing on large and medium sized mammals. Research and biomonitoring strategy currently being designed for the next 5 years (Brugiere pers. comm. 2025).

Table 4. Conservation activities reported for Lac Télé Community Reserve

Category	Specific activity	Description	Implementing organization(s)	Year of activity
2 Counter-wildlife crime	2.1 Implement road blocks to inspect cars for illegal ape bushmeat	One road block in place since 2000. 1,161 Kg of bushmeat seized in 2024 (5, 921 Kg in 2021-2024)(Brugiere pers. comm. 2025).	Wildlife Conservation Society	2000-Ongoing (2025)
2 Counter-wildlife crime	2.10 Inform hunters of the dangers (e.g., disease transmission) of handling ape meat	One wildlife health officer in place in reserve staff since 2022. Awareness campaigns on zoonoses risk (Ebola, Mpox) conducted every year. In 2024 : 7 villages/ 330 people reached (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
2 Counter-wildlife crime	2.11 Implement monitoring surveillance strategies (e.g., SMART) or use monitoring data to improve effectiveness of patrols	SMART system in place since 2010. Earth Ranger in place since 2023 (Brugiere pers. comm. 2025).	Wildlife Conservation Society	2010-Ongoing (2025)
2 Counter-wildlife crime	2.13 Provide sustainable alternative livelihoods; establish fish- or domestic meat farms	By-laws (developed conjointly by reserve staff and local community) on sustainable fishing activities in place since 2007 (Brugiere pers. comm. 2025).	Wildlife Conservation Society	2007-Ongoing (2025)
2 Counter-wildlife crime	2.14 Employ hunters in the conservation sector to reduce their impact	80% of reserve rangers come from local villages – so are presumably former hunters (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
2 Counter-wildlife crime	2.3 Conduct regular anti-poaching patrols	2024 : 71 patrols and 3,105 man-days of rangers in the field ; 9 poachers arrested; 1,161 kg of bushmed seized (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
2 Counter-wildlife crime	2.5 Inspect bushmeat markets for ape species	Busmeat markets are inspected regularly at the village level. Last bushmeat survey was carried out in 2023 in five villages over a year (Brugiere pers. comm. 2025)	Wildlife Conservation Society	2023-Ongoing (2025)
2 Counter-wildlife crime	2.6 Regularly de-activate/remove ground snares	Conducted during ranger field patrols. Snare poaching is not common in the reserve (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
2 Counter-wildlife crime	2.7 Provide better equipment (e.g., guns) to anti-poaching ranger patrols	Field equipment for rangers is renewed on regular basis. Rangers receive new equipment every year (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
2 Counter-wildlife crime	2.8 Provide training to anti-poaching ranger patrols	Every ranger undergoes recycling training session (4 days) every year (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
3 Species health	3.12 Detect & report dead apes and clinically determine their cause of death to avoid disease transmission	Detection system in place since 2022 run by wildlife health officer with local communities (see also 2.10). One gorilla carcass reported and analyzed in 2024 (cause of death unknown but not caused by virus infection) (Brugiere pers. comm. 2025).	Wildlife Conservation Society	2022-Ongoing (2025)
4 Education & awareness	4.1 Educate local communities about apes and sustainable use	Awareness campaigns run in the Reserve village every year by education officer. Subjects include ape conservation. 2024 figures : 2 awareness campaigns carried out in the Reserve’s 27 villages, reaching 762 people. In addition, 11 primary schools targeted reaching 802 pupils (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
4 Education & awareness	4.2 Involve local community in ape research and conservation management	Any ape research activity (survey, ecological study) involves local community members: field assistant, trackers, porters (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
5 Protection & restoration	5.10 Use prescribed burning within the context of home range size and use	Awaraness campaign on fire carried out each year in the Reserve; by-laws on fire management in the Reserve under development (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
5 Protection & restoration	5.5 Demarcate and enforce boundaries of protected areas	80% of the Reserve boundaries are natural (rivers); 20% artificial boundaries have been demarcated with boards (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
7 Economic & other incentives	7.2 Provide non-monetary benefits to local communities for sustainably managing their forest and its wildlife (e.g., better education, infrastructure development)	Community conservation activities implented in the reserve focus on three type of activities : i) promote sustainable use of natural resources (fish), improving living conditions (school, health, water etc.) and developing income generating activities (honey, cocoa) (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
8 Permanent presence	8.1 Run research project and ensure permanent human presence at site	Research projects continuously run in the reserve (WCS staff + external researchers; Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)
8 Permanent presence	8.3 Permanent presence of staff/manager	Reserve staff (rangers, officers, assisitants, etc.) always in the field (Brugiere pers. comm. 2025).	Wildlife Conservation Society	Ongoing (2025)

Conservation activities

Challenges

Table 5. Challenges reported for Lac Télé Community Reserve

Challenges	Specific challenges	Source	Year(s)
1 Site management	1.3 Corruption	Trivellini, G. pers. comm. 2022	Ongoing (2022)
3 Engaged community	3.1 General lack of community engagement or support	Reserve annual activity reports	Ongoing (2025)
	Other (Basic services (education, health, justice, security, transport, etc.) not ensured by State local services. Pressures on Reserve to deliver basic services)	Reserve annual activity reports	Ongoing (2025)
4 Institutional support	4.2 Lack of government support	Reserve annual activity reports	Ongoing (2025)
	Other (Reserve located in remote place making any field operation costly)	Reserve annual activity reports	Ongoing (2025)
5 Ecological context	5.1 Ecological constraints (e.g., susceptibility to climate change, difficult terrain)	Reserve annual activity reports	Ongoing (2025)
2 Resources and capacity	2.4 Lack of continuous/long-term funding	Reserve annual activity reports	Ongoing (2025)

Challenges

Enablers

Table 6. Enablers reported for Lac Télé Community 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

Enablers

Research activities

WCS implements wildlife surveys every 5 years, in order to establish the densities of large and medium sized mammals, including great apes. Two PhD projects related to apes are ongoing i) spatial ecology of the gorillas (K. Meier/ Univ. Yale); ii) Inter group communication of gorillas (A. Michel/ Univ. Davies). One additional PhD study (Hunting patterns by local communities in the Reserve by B. Christin) and a Post Doctoral study (Material culture, nesting behaviour and tool use, of the RCLT chimpanzees by T. Romani) will start in 2025.
Between 2008 and 2010, the first in-depth studies on the feeding and nesting ecology of gorillas were carried out in the Lac Télé Community Reserve. Kalan (2008) conducted one of the earliest investigations focused on the diet and nest-building behavior of Western lowland gorillas (Gorilla gorilla gorilla). This research provided critical insight into the gorillas’ nesting habits and the types of vegetation they relied on for food. Building on these findings, Kalan et al. (2010) produced a preliminary report further exploring the feeding and nesting behavior of swamp-dwelling gorillas, highlighting the species’ remarkable ability to adapt to flooded environments.
After a decade-long pause, the study of great apes in the region experienced a renewed momentum between 2022 and 2024. Meier (2024) led a comprehensive field study on the ecology and conservation of great apes, addressing key themes such as habitat use, human-induced pressures, and the implementation of effective monitoring strategies. Around the same time, Redjali (2024) investigated how chimpanzees navigate and utilize space in a human-altered, seasonally flooded landscape. Her work emphasized the chimpanzees’ ecological flexibility and their capacity to adapt to disturbed habitats. In 2024, the research landscape became even more dynamic with the introduction of methodological innovations and more targeted ecological studies. Christin (2024) focused on primate density—particularly great apes—within a transitional ecotone zone in northern Congo. His work explored how hunting pressure influences species distribution across these shifting habitats. Caillaud (2024) explored the potential of using fixed-wing drones for surveying great ape populations, a promising avenue for non-invasive monitoring in the flood-prone and logistically challenging environment of the reserve. Michel (2024) tested a novel dual-method approach to track social interactions within gorilla groups, offering new perspectives on group dynamics and social cohesion.
From 2023 to 2024, conservation research in the Lac Télé Reserve has also been informed by broader investigations into hunting pressure and its indirect consequences for great apes. Bondeko et al. (2024) conducted a study on game hunting and the financial dynamics of the bushmeat trade. Although not exclusively focused on great apes, their findings offered crucial context on the indirect threats posed to these species through human exploitation of wildlife. Complementing this work, Romani et al. (2025) analyzed trends in wildlife seizures between 2021 and 2024. While great apes were not always explicitly identified among the confiscated species, the data offered valuable indirect insights into the risks faced by these primates due to illegal hunting activities.

Documented behaviours

Table 7. Behaviours documented for Lac Télé Community Reserve

Category	Behavior	Observation type	Prevalence	Observation dates	Source	Habituation	Species	Comment
	Not reported

Behaviours

Exposure to climate change impacts

As part of a study on the exposure of African great ape sites to climate change impacts, Kiribou et al. subm. extracted climate data and data on projected extreme climate impact events for the site. Climatological characteristics were derived from observation-based climate data provided by the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP, www.isimip.org). Parameters were calculated as the average across each 30-year period. For 1981-2010, the EWEMBI dataset from ISIMIP2a was used. For the two future periods (2021-2050 and 2071-2099) ISIMIP2b climate data based on four CMIP5 global climate models were used. For future projections, two Representative Concentration Pathways (RCP) were used. RCP 2.6 is a scenario with strong mitigation measures in which global temperatures would likely rise below 2C. RCP 6.0 is a scenario with medium emissions in which global temperatures would likely rise up to 3C by 2100. For the number of days with heavy precipitation events, the 98th percentile of all precipitation days (>1mm/d) was calculated for the 1979-2013 reference period as a threshold for a heavy precipitation event. Then, for each year, the number of days above that threshold was derived. The figures on temperature and precipitation anomaly show the deviation from the mean temperature and mean precipitation for the 1979-2013 reference period.

The estimated exposure to future extreme climate impact events (crop failure, drought, river flood, wildfire, tropical cyclone, and heatwave) is based on a published dataset by Lange et al. 2020 derived from ISIMIP2b data. The same global climate models and RCPs as described above were used. Within each 30-year period, the number of years with an extreme event and the average proportion of the site affected were calculated (see Kiribou et al. subm. for details).

Table 8. Estimated past and projected climatological characteristics in Lac Télé Community Reserve

Value	1981-2010	2021-2050, RCP 2.6	2021-2050, RCP 6.0	2071-2099, RCP 2.6	2071-2099, RCP 6.0
Mean temperature [C]	25.1	26.4	26.2	26.7	27.7
Annual precipitation [mm]	1559	1630	1618	1643	1617
Max no. consecutive dry days (per year)	10.4	10	10.9	9.3	11.7
No. days with heavy precipitation (per year)	6.6	15	14.3	14.9	15.7

Table 9. Projected exposure of apes to extreme climate impact events in Lac Télé Community Reserve

Type	No. of years with event (2021-2050, RCP 2.6)	% of site exposed (2021-2050, RCP 2.6)	No. of years with event (2021-2050, RCP 6.0)	% of site exposed (2021-2050, RCP 6.0)	No. of years with event (2070-2099, RCP 2.6)	% of site exposed (2070-2099, RCP 2.6)	No. of years with event (2070-2099, RCP 6.0)	% of site exposed (2070-2099, RCP 6.0)
Crop failure	16.5	0	16.5	0	14	0	29	0
Drought	0	0	0	0	0	0	0	0
Heatwave	9	69.38	5	79.17	8	81.89	14	88.76
River flood	1	0.96	0.75	0.47	1.25	0.61	1.5	2.92
Tropical cyclone	0	0	0	0	0	0	0	0
Wildfire	30	0.36	30	0.36	29	0.32	29	0.33

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  Precipitation anomaly in Lac Télé Community Reserve

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  Temperature anomaly in Lac Télé Community Reserve

External links

WCS Lac Télé Community Reserve

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Page created by: Toni Romani (WCS Research officer, Lac Tele Community Reserve), David Brugiere (WCS Project Director, Lac Tele Community Reserve) & Guido Trivellini Date: 2022-04-08

Page updated by: Toni Romani, David Brugiere Date: 2025-05-28