Country: Sierra Leone
Administrative region: Northern (Province)
Central co-ordinates: 8.91810 N, 10.79845 W
Area: 402km²
A(i)Site contains one or more globally threatened species, A(iii)Site contains one or more highly restricted endemic species that are potentially threatened, B(ii)Site contains an exceptional number of species of high conservation importance
This site qualifies as an IPA as it contains globally significant populations of twenty-four species that trigger criterion A(i), one species that triggers criterion A(iii), and six species that trigger B(ii).
The Tingi Hills IPA is situated in the north-eastern escarpment of Sierra Leone, along the eastern border with the Republic of Guinea. These hills form part of the Guinea Dorsale that extends from the Foula Djalon Plateau. Next to the Loma Mountains, the Tingi Hills are the second most prominent mountain range in the country. The highest point at this site is the Sankan Biriwa massif, which rises to 1705 m asl. This massif is the source of tributaries of two major rivers, the Sewa and the Mano, which descend the massif in a series of cascades and rapids. This IPA boundary closely aligns to the area of the Tingi Hills Non Hunting Forest Reserve (Protected Planet 2024).
This IPA belongs to the Loma-Man Highlands phytogeographic region. The Tingi Hills IPA is a globally significant site for many species, including at least twenty-four threatened and six nationally endemic species. National endemics recorded at the site are all associated with submontane grassland and inselberg elements, including Afrotrilepis jaegeri (LC), Bulbostylis neocapitata (LC), Dryopteris amblyodonta (EN), Gladiolus leonensis (EN), Loudetia jaegeriana (NE) and Vernonia jaegeri (EN). The Tingi Hills show a strong botanical affinity to the nearby Loma Mountains IPA, which have been comparatively more extensively studied. A. jaegeri, B. neocaptata, G. leonensis and V. jaegeri are only found within Loma Mountains and Tingi Hills IPAs.
The Tingi Hills is the only place that the perennial grass, Schizachyrium penicillatum (EN), has been collected in Sierra Leone. It is also known from the Pita and Kindia Prefactures in Guinea, and there are also unverified records from southwest Burkina Faso (Cantiero & Cheek 2019). This IPA holds globally and nationally significant populations for this species. Despite having a broad ecological range, spanning both sandstone and granite habitats, this species has not been collected widely. Further research and targeted survey for this species is recommended.
Stonesia gracilis (Podostemaceae) has been recorded at the site (Morton, J.K.2933). This rheophytic herb is currently assessed as Critically Endangered based on its confirmed occurrence at a single site in Guinea (Cheek & Ouedraogo 2018) however, there is evidence that this species may occur more widely, including two locations in Sierra Leone and four in Guinea (van der Burgt pers. comms 2024). Considering the taxonomic det. of these specimens are valid, the conservation status of this species may be downgraded. Additionally, it is likely that threatened Podostemaceae occur at the waterfalls throughout Tingi, although S. gracilis is currently the only record of Podostemaceae there. Further investigation into this habitat at the site recommended.
This IPA falls within the Guinean Montane Forests ecoregion (Dinerstein et al. 2017). The vegetation of the Tingi Hills is comprised of submontane forest and submontane grassland interspersed by inselberg peaks and rolling hills. This gradually transitions into moist forest-savanna or gallery forest along drainage lines. The Tingi Hills is known to contain five rare and globally threatened habitats: Low-altitude evergreen forest and gallery forest, Submontane forest (500+ m), Submontane grassland (mainly 1000+ m), Threatened Podostemaceae habitat and Granite inselbergs.
Closed forests at the base of the hills are discontinuous and mostly secondary. Much of the predicted native vegetation on these lowland areas (evergreen and semi-deciduous forest) has been degraded due to agricultural practices and fire (Cole 1967). As a result, many moist forest species have been replaced by typical savanna trees in derived vegetation (Cole 1967). The southern portion of the site is relatively intact, featuring stands of dense primary forest (Global Forest Watch 2024), while the northeast exhibits a drier forest-savanna mosaic (Cole 1968). The open Guinea savanna vegetation on the eastern slopes contains fire resistant species such as Lophira lanceolata, Parkia biglobosa, Pterocarpus erinaceus and tall grasses including Anadelphia leptocoma, A. tectorum and Hyparrhenia diplandra.
The tree composition of the gallery forests is similar to that of moist lowland forests, displaying a diverse canopy and abundant epiphytes. Dominant species include Amphimas pterocarpoides, Bombax buonopozense, Cola lateritia var. maclaudii, Entandrophragma utile, Odyendea gabunensis, Parinari excelsa, Piptadeniastrum africanum and Uapaca guineensis (Cole 1968). Gallery forests at higher altitudes at the site have a greater presence of tree ferns (Cyathea and Marattia) and bamboo thickets (Oxytenanthera abyssinica) (Cole 1967).
Closed forests transition to submontane forest at approx. 500 m a.s.l. (Couch et al. 2019). This submontane forest is characterized by a small number of lowland species that become more prevalent at higher altitudes, with dominant species including Parinari excelsa and Kotschya ochreata var. ochreata, alongside shrubs such as Droogmansia scaettaiana, Rosettea elliotii, and Pogospermum depauperatum (Cole 1968). Near grassland edges, fire-adapted shrubs like Syzygium guineense are more common (Cole 1968).
Annual fires play a crucial role in maintaining plant communities in submontane grasslands (Couch et al. 2019). At higher altitudes (~1200 m) the treeline ends abruptly and transitions into submontane meadows interspersed with outcropping inselberg domes. Dominant species in the submontane grassland include Ctenium newtonii, Hyparrhenia nyassae and Loudetiopsis chrysothrix, along with Gladiolus spp., Coleus lateriticola, C. lyratus, and Cyanotis longifolia, as well as Euphorbia depauperata, Thesium tenuissimum and Vernonia jaegeri (Cole 1968).
Inselbergs often appear desolate during the dry season, however in the wet season they are covered in vegetation of high diversity. Small-scale ecological alterations create a mosaic of plant communities, with nine distinct microhabitats identified on inselbergs in West Africa (Porembski et al. 1994, Muller 2007). The vegetation in ephemeral flush habitats is dynamic and rich in carnivorous plants and monocotyledons (Muller 2007). Inselberg domes are typically dominated by sedge communities, with tufted Afrotrilepis pilosa and the endemic orophyte Afrotrilepis jaegeri prevalent on these steep slopes (Cole 1968). Near the summit of Sankan Biriwa, other dominant species recorded include Loudetiopsis chrysothrix and shrubby herbs such as Melastomastrum capitatum, Coleus monostachyus, and C. pobeguinii (Cole 1968). On the less steep rocky slabs, saxicolous plants like Mesanthemum jaegeri, Gladiolus aequinoctialis, the orchid Polystachya microbambusa, as well as various lichens and mosses can be found.
The geology of the Tingi Hills is primarily felsic, dating back to the Archean (Williams 1978). The ancient gneisses at the site (part of the Earth’s early crust) were modified upon contact with the heat and magma from later granitoid intrusions. This interaction resulted in migmatitic margins at the site where the gneisses partially melted, leading to a gradational transition between the two rock types (Rollinson 2018). Such features are characteristic of the complex geological histories at the site involving multiple cycles of crustal melting and magmatic intrusion. The younger granites that form the inselberg formations at the site are comprised of both biotite and porphyroblastic granite, which are likely cogenetic, having formed from the same magmatic source and during the same intrusion event (Rollinson 2018). The soils derived from these parent rocks varies in composition across the site, with slopes generally exhibiting leached soils, while valleys retain relatively fertile conditions. Cambisols- less developed soils with moderate fertility- are predominantly found at higher elevations, while Acrisols- highly weathered, acidic soils with lower fertility typical of the tropics- are present in lowland areas (Poggio, L et al. 2020).
The intensity of human activities varies across the site. Within the IPA land use categories include conservation, commodities (such as agriculture and mining), and small settlements (Dugbema, Bendu, Kiabgasima, Kenewa, Yarakonko, Dandu, Nelikoro, Gbeaia; Google Earth 2024). This IPA largely overlaps with the Tingi Hills No Hunting Forest Reserve, a protected area (PA) where the capture of animals is strictly prohibited and extractive activities, such as logging, are permitted only under stringent conditions (Forestry Division 2017). Currently, there is no management plan for this PA, nor are there actions in place to incorporate and monitor plant diversity at the site (FAO 2023).
The upper areas of the hills are lightly impacted due to challenging topography and limited road access. In contrast, the lowland regions have experienced significant tree cover loss over the past 20 years (Global Forest Watch 2024) and continue to face threats from human activities, including land clearing for agriculture and fire. Anthropogenic fires linked to slash-and-burn agricultural practices particularly threaten native vegetation not adapted to high-frequency fire, such as moist closed-canopy forests. Consequently, lowland areas have degraded, shifting in composition from moist deciduous rainforest species to derived savanna woodlands (Cole 1967).
The IPA is surrounded by several small villages that utilize the area for timber and non-timber forest products (NTFPs); however, data on the extent of these impacts are lacking.
Mining, both small and commercial scale, poses a significant threat to the site. Bravura Mining (SL) Limited holds an active nickel exploration license over the northern half of the IPA (GoSL 2024). Although there are currently no active licenses, mining remains a potential threat, particularly to the lower portions of the site where inselbergs are concentrated. These habitats, predominantly formed of granite, are crucial for concrete production when crushed and are used in large infrastructure projects, including buildings, dam walls, and road construction (Couch et al. 2019). Small-scale mining activities have been recorded along the rivers at the southern end of the reserve along the rivers (Okoni Williams et al. 2001, Birdlife 2024).
This site provides critical habitat for numerous species, earning its designation as both an Important Bird Area (IBA) and an Important Plant Area (IPA). Notably, it is home to the endemic toad Bufo cristiglans (Birdlife 2024). While the IPA is utilized by local communities, specific details regarding these uses remain undocumented. The site serves as an important water catchment, offering essential ecosystem services such as erosion control, water quality and filtration. The Sankan Biriwa Massif of the Tingi Hills is a key catchment area for two major rivers in Sierra Leone: the Sewa and Moa. The Bafi, Moni, and Mansayi rivers are tributaries of two of Sierra Leone's seven main rivers. The Bafi originates from the western slopes, while the Mansayi arises from the southeastern slopes; both rivers flow southward and converge to form a tributary of the Sewa River. The Moni River, which originates in the northeast, flows into the Meli River, which runs along the eastern border of Sierra Leone as a tributary of the Moa River (Cole 1967).
Gabriella Hoban, Royal Botanic Gardens, Kew
Xander van der Burgt, Royal Botanic Gardens, Kew
Martin Cheek, Royal Botanic Gardens Kew
Species | Qualifying sub-criterion | ≥ 1% of global population | ≥ 5% of national population | 1 of 5 best sites nationally | Entire global population | Socio-economically important | Abundance at site |
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Acalypha guineensis J.K. Morton & G.A.Lavin | A(i) | ![]() |
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Anubias gracilis A.Chev. ex Hutch. | A(i) | ![]() |
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Baccharoides nimbaensis (C.D.Adams) Isawumi, El-Ghazaly & B.Nord. | A(i) | ![]() |
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Coleus pobeguinii Hutch. & Dalziel | A(i) | ![]() |
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Dissotis leonensis Hutch. & Dalziel | A(i) | ![]() |
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Homalium smythei Hutch. & Dalziel | A(i) | ![]() |
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Hypolytrum cacuminum Nelmes | A(i) | ![]() |
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Rhytachne glabra (Gledhill) Clayton | A(i) | ![]() |
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Schizachyrium lomaense A.Camus | A(i) | ![]() |
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Schizachyrium penicillatum Jacq.-Fél. | A(i) | ![]() |
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Xyris festucifolia Hepper | A(i) | ![]() |
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Xysmalobium samoritourei Goyder | A(i) | ![]() |
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Scarce |
Dryopteris amblyodonta J.P.Roux | A(i) | ![]() |
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Gladiolus leonensis Marais | A(i) | ![]() |
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Vernonia jaegeri C.D.Adams | A(i) | ![]() |
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Loudetia jaegeriana A.Camus | A(iii) | ![]() |
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Eriosema spicatum subsp. collinum (Hepper) J.K.Morton ex Verdc. | A(i) | ![]() |
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Entandrophragma utile (Dawe & Sprague) Sprague | A(i) | ![]() |
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Homalium smythei Hutch. & Dalziel | A(i) | ![]() |
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Mesanthemum jaegeri Jacq.-Fél. | A(i) | ![]() |
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Pavetta platycalyx Bremek. | A(i) | ![]() |
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Pterocarpus erinaceus Poir. | A(i) | ![]() |
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Stonesia gracilis G.Taylor | A(i) | ![]() |
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Strychnos melastomatoides Gilg. | A(i) | ![]() |
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Terminalia ivorensis A.Chev. | A(i) | ![]() |
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Acalypha guineensis J.K. Morton & G.A.Lavin
Anubias gracilis A.Chev. ex Hutch.
Baccharoides nimbaensis (C.D.Adams) Isawumi, El-Ghazaly & B.Nord.
Coleus pobeguinii Hutch. & Dalziel
Dissotis leonensis Hutch. & Dalziel
Homalium smythei Hutch. & Dalziel
Hypolytrum cacuminum Nelmes
Rhytachne glabra (Gledhill) Clayton
Schizachyrium lomaense A.Camus
Schizachyrium penicillatum Jacq.-Fél.
Xyris festucifolia Hepper
Xysmalobium samoritourei Goyder
Dryopteris amblyodonta J.P.Roux
Gladiolus leonensis Marais
Vernonia jaegeri C.D.Adams
Loudetia jaegeriana A.Camus
Eriosema spicatum subsp. collinum (Hepper) J.K.Morton ex Verdc.
Entandrophragma utile (Dawe & Sprague) Sprague
Homalium smythei Hutch. & Dalziel
Mesanthemum jaegeri Jacq.-Fél.
Pavetta platycalyx Bremek.
Pterocarpus erinaceus Poir.
Stonesia gracilis G.Taylor
Strychnos melastomatoides Gilg.
Terminalia ivorensis A.Chev.
Habitat | Qualifying sub-criterion | ≥ 5% of national resource | ≥ 10% of national resource | 1 of 5 best sites nationally | Areal coverage at site |
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Submontane grassland | C(i) | ![]() |
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Submontane grassland
General site habitat | Percent coverage | Importance |
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Forest - Subtropical/Tropical Moist Lowland Forest | ![]() |
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Forest - Subtropical/Tropical Moist Montane Forest | ![]() |
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Wetlands (inland) - Permanent Rivers, Streams, Creeks [includes waterfalls] | ![]() |
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Wetlands (inland) - Seasonal/Intermittent/Irregular Rivers, Streams, Creeks | ![]() |
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Savanna - Moist Savanna | ![]() |
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Rocky Areas - Rocky Areas [e.g. inland cliffs, mountain peaks] | ![]() |
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Grassland - Subtropical/Tropical High Altitude Grassland | ![]() |
Forest - Subtropical/Tropical Moist Lowland Forest
Forest - Subtropical/Tropical Moist Montane Forest
Wetlands (inland) - Permanent Rivers, Streams, Creeks [includes waterfalls]
Wetlands (inland) - Seasonal/Intermittent/Irregular Rivers, Streams, Creeks
Savanna - Moist Savanna
Rocky Areas - Rocky Areas [e.g. inland cliffs, mountain peaks]
Grassland - Subtropical/Tropical High Altitude Grassland
Land use type | Percent coverage | Importance |
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Nature conservation | ![]() |
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Agriculture (arable) | ![]() |
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Agriculture (pastoral) | ![]() |
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Harvesting of wild resources | ![]() |
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Residential / urban development | ![]() |
Nature conservation
Agriculture (arable)
Agriculture (pastoral)
Harvesting of wild resources
Residential / urban development
Protected area name | Protected area type | Relationship with IPA | Areal overlap |
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Tingi Hills No Hunting Forest Reserve | Forest Reserve (conservation) | IPA encompasses protected/conservation area | ![]() |
Tingi Hills No Hunting Forest Reserve
Designation name | Protected area | Relationship with IPA | Areal overlap |
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Tingi Hills Non-hunting Forest Reserve | Important Bird Area | protected/conservation area overlaps with IPA | ![]() |
Tingi Hills Non-hunting Forest Reserve
Management type | Description | Year started | Year finished |
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No management plan in place | ![]() |
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No management plan in place
Vegetation of rock outcrops in Guinea: granite inselbergs, sandstone table mountains and ferricretes – remarks on species numbers and endemism.
Flora, Vol 189, page(s) 315-326
Protected Areas (WDPA)
The Vegetation of Sierra Leone
Terrestrial Ecoregions of the World: A New Map of Life on Earth: A new global map of terrestrial ecoregions provides an innovative tool for conserving biodiversity
BioScience, Vol 51, page(s) 933-938
Threatened Habitats and Tropical Important Plant Areas of Guinea, West Africa
GoSL Online Repository
Important Bird Area factsheet: Tingi Hills Non-hunting Forest Reserve (Sierra Leone)
Herbaceous Vegetation of Seasonally Wet Habitats on Insebergs and Lateritic Crusts in West and Central Africa
Folia Geobotanica, Vol 42, page(s) 29-61
Sierra Leone's Second National Biodiversity Strategy and Action Plan 2017-2026
The Archaean geology of Sierra Leone
The geochemical evolution of Archaean felsic gneisses in the West African Craton in Sierra Leone
Journal of African Earth Sciences, Vol Volume 143, page(s) 28-39
Schizachyrium penicillatum
The IUCN Red List of Threatened Species Available online
Legal Study on Forests in Sierra Leone: Strengthening the forestry legal framework to address transboundary challenges and degradation trends in the Upper Guinean forest ecosystem
SoilGrids 2.0: producing soil information for the globe with quantified spatial uncertainty
SOIL, Vol 7, page(s) 217-240
An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm
Bioscience, Vol 67, page(s) 534-545
Stonesia gracilis
The IUCN Red List of Threatened Species
Gabriella Hoban, Xander van der Burgt, Martin Cheek (2025) Tropical Important Plant Areas Explorer: Tingi Hills (Sierra Leone). https://tipas.kew.org/site/tingi-hills/ (Accessed on 16/02/2025)