Mont Kala

Nkol Nlong

CMNTIPA009
Mont Kala

Country: Cameroon

Administrative region: Centre (Region)

Central co-ordinates: 3.83480 N, 11.35000 E

Area: 33km²

Qualifying IPA Criteria

A(i)Site contains one or more globally threatened species

IPA assessment rationale

Mount Kala qualifies as an IPA on the basis of several globally threatened species which are present here and at few other locations, including some that are endemic to the site or the wider Yaounde area.

Site description

Mont Kala is an east-west oriented ridge approximately 7 km in length located about 20 km west of Yaoundé. It is part of the chain of prominences located between the main N3 and N3A roads running into Yaoundé from the west which form the southern section of the steep topography flanking the western side of Yaoundé. The ridge is mostly around 900–950 m high with several summits rising to over 1,000 m.

Botanical significance

Many botanical collections were made in the Yaoundé area by Zenker and Staudt in the 1890s (Cheek et al., 2011). While unfortunately most of these can not be precisely located, the western hills are the main surviving areas where some natural habitat remains. These are forested inselbergs and provide an interesting flora differing from the lower surrounding areas. Subsequent collecting has recorded several globally threatened species from these hills, including Mount Kala which is one of the least degraded due probably to its greater distance from the centre of Yaoundé. In particular, two species of Afrothismia are currently considered endemic to Mount Kala. Pavetta bidentata var. sessilifolia is also considered endemic to Mount Kala and the Kombing area 30 km to the Southwest. Disperis aphylla (VU) appears to be only recorded in Cameroon from this site. Gastrodia africana is a very rare and little understood species which was apparently collected at Mount Kala in 1968 (although the specimen appears to be missing) and from one or two other locations. Other species such as Callichila monopodialis (VU), Tricalysia amplexicaulis (provisionally VU, Onana & Cheek, 2011), T. atherura (VU) and Culcasia sanagensis (VU) are mainly known from here and other hills in the Yaoundé area.

Habitat and geology

The hills around Yaoundé rise from the South Cameroon plain between the Sanaga fault and the north-thrusting Congo craton. They are formed from high grade metamorphic rocks, mainly granulites and migmatites also referred to as embrichite gneiss (Achoundog, 1985), formed from sedimentary and igneous protoliths and apparently dating from around 600 mya (Nzenti, 1988; Tchouatcha et al., 2018; Ngnotue et al., 2012). The soils and topology of these hills are often unstable and susceptible to catastrophic landslips (Zogning et al., 2007).
Precipitation in Yaoundé is 1,605 mm per annum, falling in a bimodal pattern with a small (March-June) and greater (September-November) wet season interspersed with a drier period (July-August) and a second more severe dry period between December and February when mean monthly rainfall drops below the relatively flat mean monthly temperature curve (range: 2.8–25.47 °C) on a Walter-Leith type chart (Simo et al., 2009; Bissaya et al., 2014; Noumi, 2015). This is below the level of rainfall normally thought necessary to sustain evergreen tropical forest (Cheek et al., 2011), although the level maybe higher on the summits with orographic precipitation likely (Noumi, 2015; Simo et al., 2009). Achoundong (1985) describes the vegetation as semi-deciduous although the lower altitudes are largely cultivated and even up to the highest altitude there is cultivation and wood extraction (Mbenoun Masse & Makon, 2019).
Madiapevo et al. (2017) describe the summit forest as diverse and having affinities with other West African submontane forest but with high representation of Clusiaceae and Cola. Common species included Allanblackia gabonensis, Tabernaemontana crassa, Santiria trimera, Ceolocaryon preussii, Pycnanthus angolensis, Cola attiensis var. bodardii and Aulacocalyx jasmiflora.

Conservation issues

Yaoundé was the second largest city in Cameroon at the last census but has been estimated to be growing at over 5% per year. It is now estimated to have the largest population in the country and is predicted to reach 5.7 million by 2030 (United Nations, 2018). All of the western hills and areas of vegetation have been seriously degraded or lost due to small scale agriculture, suburban spread, hotel development, extraction of timber and quarrying. Mount Kala is one of the furthest from the centre but has not escaped habitat loss at all altitudinal levels. Clearance for agriculture and logging has particularly impacted the slopes up to 1,000 m, with cleared areas easily visible on satellite imaging. A road has been bulldozed from the base of the site as far as the rock cliff and land is being sold off (R. Fotso, 2021, pers. comm, 9 June).
The site is included in the Mbam Minkom-Mount Kala Important Bird Area (Bird Life International, 2020) and in 2009 Mount Kala was considered the only other remaining nesting site in the Yaoundé area for Picathartes oreas (VU) other than the larger Mbam Minkom massif (Awa II et al., 2009).

Ecosystem services

The hills around Yaoundé are unstable and therefore remaining forested vegetation is important in preventing landslips which have claimed lives and caused damage such as the Oyom Abang landslide in western Yaoundé in September 1990 which killed five people (Zogning et al., 2007; Mukenga et al., 2016). In a rapidly growing metropolitan area such sites are also an important recreational and educational resource for the growing population and the survival of rare species and primary vegetation greatly increases the value of such sites. For example, the many important and threatened timber species are known from the site, make them useful for students studying forestry or biodiversity at the Yaoundé universities and for informing the public about the country's natural heritage.
The site provides habitat to threatened bird species such as Picarthes oreas (VU).

Site assessor(s)

Bruce Murphy, Royal Botanic Gardens, Kew

Xander van der Burgt, Royal Botanic Gardens, Kew

Dr Vincent Droissart, Institute of Research for Development. Marseille

Professor Bonaventure Sonke, University of Yaounde I

IPA criterion A species

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
Afrothismia amietii Cheek A(i) True True True True False
Afrothismia pusilla Sainge & Kenfack A(i) True True True True False
Callichilia monopodialis (K.Schum.) Stapf A(i) True True True False False
Culcasia sanagensis Ntepe-Nyame A(i) True True True False False
Drypetes molunduana Pax & K.Hoffm. A(i) False False False False False
Gastrodia africana Kraenzl. A(i), A(iii) True True True False False
Prioria joveri (Normand ex Aubrév.) Breteler A(i) True True True False False
Loesenera talbotii Baker f. A(i) True False True False False
Pavetta bidentata Hiern var. sessilifolia S.D.Manning A(i) True True True False False
Tricalysia atherura N.Hallé A(i) True False True False False
Turraeanthus mannii Baill. A(i) True True True False False
Allanblackia gabonensis (Pellegr.) Bamps A(i) False False False False False
Diospyros crassiflora Hiern A(i) False False False False False
Entandrophragma cylindricum (Sprague) Sprague A(i) False False False False False
Entandrophragma utile (Dawe & Sprague) Sprague A(i) False False False False False
Garcinia kola Heckel A(i) False False False False True
Khaya anthotheca C.DC. A(i) False False False False True
Kylicanthe cornuata Descourv. & Stévart & Droissart A(i) True False False False False
Oxyanthus doucetii Sonké & O.Lachenaud A(i) True True True False False
Disperis aphylla Kraenzl. ex De Wild. & T.Durand A(i) False True True False False

Afrothismia amietii Cheek

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
True
Socio-economically important:
False
Abundance at site:

Afrothismia pusilla Sainge & Kenfack

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
True
Socio-economically important:
False
Abundance at site:

Callichilia monopodialis (K.Schum.) Stapf

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Culcasia sanagensis Ntepe-Nyame

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Drypetes molunduana Pax & K.Hoffm.

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
False
1 of 5 best sites nationally:
False
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Gastrodia africana Kraenzl.

Qualifying sub-criterion:
A(i), A(iii)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Prioria joveri (Normand ex Aubrév.) Breteler

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Loesenera talbotii Baker f.

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
False
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Pavetta bidentata Hiern var. sessilifolia S.D.Manning

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Tricalysia atherura N.Hallé

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
False
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Turraeanthus mannii Baill.

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Allanblackia gabonensis (Pellegr.) Bamps

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
False
1 of 5 best sites nationally:
False
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Diospyros crassiflora Hiern

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
False
1 of 5 best sites nationally:
False
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Entandrophragma cylindricum (Sprague) Sprague

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
False
1 of 5 best sites nationally:
False
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Entandrophragma utile (Dawe & Sprague) Sprague

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
False
1 of 5 best sites nationally:
False
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Garcinia kola Heckel

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
False
1 of 5 best sites nationally:
False
Entire global population:
False
Socio-economically important:
True
Abundance at site:

Khaya anthotheca C.DC.

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
False
1 of 5 best sites nationally:
False
Entire global population:
False
Socio-economically important:
True
Abundance at site:

Kylicanthe cornuata Descourv. & Stévart & Droissart

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
False
1 of 5 best sites nationally:
False
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Oxyanthus doucetii Sonké & O.Lachenaud

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:

Disperis aphylla Kraenzl. ex De Wild. & T.Durand

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:

General site habitats

General site habitat Percent coverage Importance
Forest - Subtropical/Tropical Moist Montane Forest No value
Rocky Areas - Rocky Areas [e.g. inland cliffs, mountain peaks] No value

Forest - Subtropical/Tropical Moist Montane Forest

Percent coverage:
No value
Importance:

Rocky Areas - Rocky Areas [e.g. inland cliffs, mountain peaks]

Percent coverage:
No value
Importance:

Land use types

Land use type Percent coverage Importance
Agriculture (arable) 20 Minor
Harvesting of wild resources 100 Minor

Agriculture (arable)

Percent coverage:
20
Importance:
Minor

Harvesting of wild resources

Percent coverage:
100
Importance:
Minor

Threats

Threat Severity Timing
Residential & commercial development - Housing & urban areas High Ongoing - increasing
Agriculture & aquaculture - Annual & perennial non-timber crops - Shifting agriculture High Ongoing - increasing
Biological resource use - Logging & wood harvesting High Ongoing - trend unknown

Residential & commercial development - Housing & urban areas

Severity:
High
Timing:
Ongoing - increasing

Agriculture & aquaculture - Annual & perennial non-timber crops - Shifting agriculture

Severity:
High
Timing:
Ongoing - increasing

Biological resource use - Logging & wood harvesting

Severity:
High
Timing:
Ongoing - trend unknown

Conservation designation

Designation name Protected area Relationship with IPA Areal overlap
Mbam Minkom-Kala IBA Important Bird Area protected/conservation area encompasses IPA No value
Mbam Minkom-Kala IBA Key Biodiversity Area protected/conservation area encompasses IPA No value

Mbam Minkom-Kala IBA

Protected area:
Important Bird Area
Relationship with IPA:
protected/conservation area encompasses IPA
Areal overlap:
No value

Mbam Minkom-Kala IBA

Protected area:
Key Biodiversity Area
Relationship with IPA:
protected/conservation area encompasses IPA
Areal overlap:
No value

Management type

Management type Description Year started Year finished
No management plan in place No value No value

No management plan in place

Year started:
No value
Year finished:
No value

Bibliography

Cheek, M., Harvey, Y. & Onana, J.M., 2011

The Plants of Mefou Proposed National Park, Yaoundé, Cameroon

BirdLife International, 2020

Important Bird Areas factsheet: Mbam Minkom - Kala.

Available online

Zogning, A., Ngouanet, C. & Tiafack, O., 2007

The catastrophic geomorphological processes in humid tropical Africa: A case study of the recent landslide disasters in Cameroon

Sedimentary Geology, Vol 199, page(s) 13 – 27 Available online

Mukenga, W,. Havenith, H.B., Dewitte, O. & R.M. Eko, 2016

Spatial Analysis of the Landslide Risk in the Cameroon Volcanic Line (CVL)

Available online

Bissaya, R., Ghogomu, R.T., Moundi, A., Njom, B. & N.S. Kanouo, 2014

Utilisation des données géologiques et gestion des informations multi-sources pour l’analyse de l’aléa glissement de terrain/éboulement dans le secteur Nord-Ouest de la région de Yaoundé

Afrique SCIENCE, Vol 10(3), page(s) 113 - 133

Noumi, E., 2015

Floristic structure and diversity of a tropical sub-montane evergreen forest, in the Mbam minkom massif (Western Yaoundé).

Journal of Biology and Life Science, Vol 6(1), page(s) 149-193

Simo, M., Droissart, V., Sonké, B. & Stévart, T., 2009

The Orchid Flora of the Mbam Minkom Hills (Yaoundé, Cameroon)

Belgian Journal of Botany, Vol 142(2), page(s) 111-123

Nzenti, J.P., Barbey, P., Macaudiere, J. & Soba, D., 1988

Origin and evolution of the late Precambrian high-grade Yaounde gneisses (Cameroon).

Precambambrian Research, Vol 38, page(s) 91-109

Tchouatcha, M.S., Kouske, A.P., Njiosseu, E.L.T., Ngouem, P.A., Ngnotue, T., Njinchuki, D.N. & Nzenti, J.P., 2018

Preserved Sedimentary Features in the Pan-African High-Grade Metamorphic Rocks from the Yaoundé Series (Cameroon)

Journal of Geosciences and Geomatics, Vol 6(3), page(s) 94-102

Ngnotué, T., Ganno, S., Nzenti, J.P., Schulz, B., Tchaptchet T.D. & Suh, C.E., 2012

Geochemistry and geochronology of Peraluminous High-K Granitic Leucosomes of Yaoundé Series ) Cameroon. Evidence for a Unique Pan-African Magmatism and Melting Event in North Equatorial Fold Belt.

International Journal of Geosciences, Vol 3, page(s) 525-548

Awa II, T., Dzikouk, G. & Norris, K., 2009

Breeding distribution and population decline of globally threatened Grey-necked Picathartes Picathartes oreas in Mbam Minkom Mountain Forest, southern Cameroon

Bird Conservation International, Vol 19, page(s) 254–264

Madiapevo, S.N., Makemteu, J. & Noumi, E., 2017

Plant Woody Diversity of the Highest Summit Forest (1156 m), in the Kala Massif, Western Yaoundé

International Journal of Current Research in Biosciences and Plant Biology, Vol 4(10), page(s) 1-30

Mbenoun Masse, P.S & Makon, S.D, 2019

Effects of human disturbance and altitudinal gradient on myriapod species richness and abundance at Mount Kala, central Cameroon

African Zoology, Vol 54(4), page(s) 215-223

Recommended citation

Bruce Murphy, Xander van der Burgt, Dr Vincent Droissart, Professor Bonaventure Sonke (2024) Tropical Important Plant Areas Explorer: Mount Kala (Cameroon). https://tipas.kew.org/site/mont-kala-2/ (Accessed on 21/05/2024)