Mont Minloua

Montagne de Mouche

CMNTIPA012
Mont Minloua

Country: Cameroon

Administrative region: Centre (Region)

Central co-ordinates: 3.88610 N, 11.43490 E

Area: 4.36km²

Qualifying IPA Criteria

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

IPA assessment rationale

Mount Minloa qualififes as a potential IPA under criterion A(i) due to the presence of several globally threatened species recorded from this site and with few other known locations. In particular, Scleria sheilae (CR) is known only from this site, while Talbotiella breteleri (CR) is otherwise recorded only from a few equally threatened Yaounde sites.

Site description

Mount Minloua is located on the western side of Yaoundé, northwest of the N'kolbisson district and northeast of the Afeme river and Mefou dam and reservoir. It is part of a chain of c. 1,000 m inselbergs in and around the western part of Yaoundé. The site includes three summits above 900m connected by ridges. Northeast of the demarcated area, the mountain has been destroyed by quarrying up to around 925 m. It is unclear from available maps what name is given to the peak rising to around 960 m located at dd 3.9038 North,11.4344 East but this is also included here.

Botanical significance

Many specimens were collected in the Yaoundé area by Zenker and Staudt as far back as the 1890s but unfortunately few of these can be located to precise areas. Subsequent collecting has recorded several rare or important species from the inselbergs on the western side of the city, including rediscovery of many of the earlier collections. The N'kolbisson area has been a particular locus for collecting, partly due to the proximity of the IRAD headquarters and other institutions. Once again, some of these latter collections, particularly a number made by de Wilde and colleagues in the 1960s can not be further located within this region which has experienced development and extensive loss of natural habitat. However, others are pinpointed to Mount Akokndoué, Mount Minloua or one of the other hills where some natural vegetation survives.
Notable amongst the globally threatened species at this site are Pterorachis zenkeri (VU), first described from Zenker and Staudt's "Yaundé station" collections and subsequently recorded here as well as at a few other sites mainly in the Yaoundé area, including the neighbouring inselbergs of Mount Akondoué and Mount Febé (Onana & Cheek, 2011). Anisotes zenkeri (EN) was similarly rediscovered at Mount Minloa and is also known from Mount Eloumden and other unlocated Yaoundé locations, as well as one other site in Central region (Cheek, 2014). Talbotiella breteleri (CR) is also endemic to the Yaoundé area, recorded from Mbam Minkom and Mount Febé as well as this site. Scleria sheilae (CR; Cheek et al., 2018) is considered locally endemic to Mount Minloa itself, having been recorded nowhere else. Eragrostis raynaliana (EN) is known from three collections in the "N'kolbisson" area, one of which is identified as this site, "la colline Minlo", as well as nearby Mount Mbankolo and two other sites outside of Yaoundé (Cheek & Lovell, 2020). Several other threatened species, including Chlorophytum staudtii (EN), Cyphostemma camerounense (EN), Momordica camerounensis (EN) may occur here, having been recorded from N'kolbisson without a precise location. Although not yet on the global Red List, Tricarpelema africanum is known from very few sites in Cameroon but is recorded from Mount Minloa and nearby Mbam Minkom.

Habitat and geology

The hills around Yaounde 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 (Achoundong 1985), formed from sedimentary and igneous protoliths and apparently dating from around 600 mya (Nzenti et al., 1988; Tchouatcha et al., 2018; Ngnotue et al., 2012).
Preciptiation 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 stable mean monthly temperature (22.8–25.47 °C) (Simo et al 2009; Bissaya et al., 2014; Madiapevo et al., 2015). This is below the level of rainfall normally thought necessary to sustain evergreen tropical forest (Cheek et al., 2011), although the level may be higher on the summits due to orographic precipitation (Noumi, 2014; Simo et al., 2009). The original forest was probably semi-deciduous (Achoundong et al.,1985) but has been heavily degraded through timber and wood extraction and cultivation.

Conservation issues

Rapid and ongoing expansion of Yaoundé threatens the remaining natural vegetation of the western inselbergs through settlement, cultivation, logging and wood extraction (Tiafack & Mbon, 2017). Successive satellite imaging reveals gradual encroachment of buildings and farms up the flanks of these hills, sometimes to the summits.
In addition mountain top quarrying has destroyed the northeastern part of the hill and is likely to expand into the designated site if not prevented.
A large dam and reservoir to the immediate south and west of the site has flooded lower lying valleys. It is not known what species may have been lost or survived from naturally marshy habitat in this area.
In addition to biodiversity conservation, there are several other good justifications (landslide prevention, tourism, recreation, education and civic pride) for preserving what remains of the natural vegetation of Mount Minloua and other Yaounde inselbergs.

Ecosystem services

As is the case with the other hills around Yaoundé, there is a high risk of landslides due to steep terrain and impervious clay beneath permeable laterite soil. Such events have claimed lives and caused extensive damage such as the Oyom Abang landslide in western Yaoundé in September 1990 which killed five people (Zogning et al., 1900; Mukenga et al., 2016; Bissaya et al., 2014). Preservation of existing forest and primary vegetation is important to preventing such disasters and flash flooding (Lachenaud et al., 2013).
The site contributes to air quality and aesthetic appeal. In a rapidly growing metropolitan area, such sites are also an important recreational and educational resource for the growing population; the survival of rare species and primary vegetation greatly increases the value of such sites. The site has been important historically to botanists and forestry students at the city's universities for educational and training purposes, and continues to be so.

Site assessor(s)

Bruce Murphy, Royal Botanic Gardens, Kew

Xander van der Burgt, Royal Botanic Gardens, Kew

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
Pterorhachis zenkeri Harms A(i) True True True False False
Anisotes zenkeri (Lindau) C.B.Clarke A(i) True True True False False
Scleria sheilae J.Raynal A(i) True True True True False
Eragrostis raynaliana Lebrun A(i) True True True False False
Talbotiella breteleri (Aubrév.) Mackinder & Wieringa A(i) True True True False False

Pterorhachis zenkeri Harms

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:

Anisotes zenkeri (Lindau) C.B.Clarke

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:

Scleria sheilae J.Raynal

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:

Eragrostis raynaliana Lebrun

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:

Talbotiella breteleri (Aubrév.) Mackinder & Wieringa

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:

General site habitats

General site habitat Percent coverage Importance
Forest - Subtropical/Tropical Moist Lowland Forest No value
Forest - Subtropical/Tropical Moist Montane Forest No value

Forest - Subtropical/Tropical Moist Lowland Forest

Percent coverage:
No value
Importance:

Forest - Subtropical/Tropical Moist Montane Forest

Percent coverage:
No value
Importance:

Threats

Threat Severity Timing
Natural system modifications - Dams & water management/use - Large dams Medium Ongoing - stable
Geological events - Avalanches/landslides Medium Ongoing - stable
Residential & commercial development - Housing & urban areas High Ongoing - increasing
Agriculture & aquaculture - Annual & perennial non-timber crops - Shifting agriculture High Ongoing - trend unknown
Energy production & mining - Mining & quarrying High Ongoing - trend unknown
Biological resource use - Logging & wood harvesting High Ongoing - trend unknown

Natural system modifications - Dams & water management/use - Large dams

Severity:
Medium
Timing:
Ongoing - stable

Geological events - Avalanches/landslides

Severity:
Medium
Timing:
Ongoing - stable

Residential & commercial development - Housing & urban areas

Severity:
High
Timing:
Ongoing - increasing

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

Severity:
High
Timing:
Ongoing - trend unknown

Energy production & mining - Mining & quarrying

Severity:
High
Timing:
Ongoing - trend unknown

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-Mt Kala IBA Important Bird Area protected/conservation area encompasses IPA No value

Mbam Minkom-Mt Kala IBA

Protected area:
Important Bird 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

Onana J.-M. & Cheek M., 2011

Red Data Book of the flowering plants of Cameroon

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

The Plants of Mefou Proposed National Park, Yaoundé, Cameroon

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

Tiafack, O. & Mbon, A.M., 2017

Urban Growth and Front Development on Risk Zones: GIS Application for Mapping of Impacts on Yaounde North Western Highlands, Cameroon

Current Urban Studies, Vol 5(2), page(s) 217-235

Achoundong, G., 1996

Les forêts sommitales du Cameroun: Végétation et flore des Collines de Yaoundé.

Bois et forêt des tropiques, Vol 247, page(s) 37-52

Lachenaud, O., Droissart, V., Dessein, S., Stévart, T., Simo, M., Lemaire, B., Taedoumg, H. & Sonké, B., 2013

New records for the flora of Cameroon, including a new species of Psychotria (Rubiaceae) and range extensions for some rare species

Plant Ecology and Evolution, Vol 146 (1), page(s) 121–133

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

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

Cheek, M., 2014

Anisotes zenkeri. The IUCN Red List of Threatened Species 2014: e.T200662A2677254.

Cheek, M., Larridon, I. & Rokni, S., 2018

Scleria shielae. The IUCN Red List of Threatened Species 2018: e.T110080777A110080779

Available online

Cheek, M. & Lovell, R., 2020

Eragrostis raynaliana. The IUCN Red List of Threatened Species 2020: e.T110091089A110091091

Available online

Recommended citation

Bruce Murphy, Xander van der Burgt (2024) Tropical Important Plant Areas Explorer: Mount Minloua (Cameroon). https://tipas.kew.org/site/mont-minloua/ (Accessed on 27/05/2024)