Volcanism

 

Geology and Volcanism

Cameroon Volcanic Chain (Suh et al., 2008)

A fault, running nearly NE-SW between two major African plates, is the origin of Mount Cameroon and other mountains on the Cameroon Volcanic Line, running 1600 km long between Annobon island in the Atlantic Ocean and Ngaoundere Plateau inland. The line is interpreted as the Central African Shear zone. Thus Mount Cameroon cannot be regarded only as a volcanco but as a volcano-tectonic fet al. 2009). 40 km to the SW of Mount Cameroon is the island of Bioko with the Pico Basile (3011m), geologically and botanically a twin of Mt Cameroon (both mountains were linked 10,000 years ago by land before the sea level rose). Moving NW from Mount Cameroon, 100 km along the fault is Mount Kupe (2064m), highest point of the Bakossi Mountains, followed by the Manenguba Massif with a peak at 2411 m, the Bambouto Mountains (peak at 2740m), Mount Oku (3011 m) in the Bamenda Highlands and further inland more mountain ranges. Mount Cameroon is a volcanic massif 50 km long and 35 km large oriented in NE – SW direction. The heart of Mount Cameroon and Mount Etinde (“small Mount Cameroon”) was formed by volcanic activities through rising of basalts since 80 million years ago. More volcanic activity took part in the Quaternary (2.5 million years ago until present) building the bulk of the main massif and creating also the crater lakes at the foothills of Mount Cameroon (Debundscha, Njonji crater lakes in the South West and Barombi Koto in the North) . The surface of the massif is formed by more than 140 recent volcanic scoria and cinder cones, created by explosive eruptions, and of lava flows. There are also some effusive volcanic mouths without cones linked to fractures.

Mount Cameroon has the most frequent eruptions of any West African volcano. The first written account of volcanic activity could be the one from the Carthaginian Hanno the Navigator, who might have observed the mountain in the 5th century BC. He described the mountain as the “Chariot of the Gods”. Moderate explosive and effusive eruptions have occurred throughout history from both summit and flank vents Mount Cameroon is the only active volcano of the Cameroon Line and erupting roughly every twenty years. There have been seven major eruptions recorded in the 20th Century: 1909, 1922, 1954, 1959, 1982, 1999 and 2000. The 1922 eruption on the southwestern flank produced a lava flow that reached the Atlantic coast at Idenau destroying the village of Bibundi, and a lava flow from a 1999 south-flank eruption stopped only 200 m from the sea, cutting the coastal highway close to Bakingili.

 

 

1999 craters 
Old craters and young lava flows

 

2000 crater  
Volcanic bomb close to 2000 crater

 

“Volcanic mouth” at more than 3000m altitude 
One of the recent eruptions
Climate

 

Climate

Mount Cameroon has a tropical seasonal climate, with one wet and one dry season. With the shift of the Inter-Tropical Convergence Zone (ITCZ), where winds from the northern and southern hemispheres meet, the area is at different times of year under the influence of either continental stable, cool and often dust laden winds from the North-East (Harmattan) or maritime moist, warm and unstable winds from the South-West (monsoon). At the west coast the high rainfalls are the result of the moist air forced to rise in a short distance up and over the slopes of the mountain. Debundscha at Cape Nachtigall is the third wettest place on earth and receives 10 m of rainfall. On the rain shadow site of the mountain – the NE slopes – rainfall is only 2 m. Rainfall tends to decrease with altitude on the mountain, the upper part of the mountain only receive 3 m per year, while the topmost part , around the peak, receives only 2 m of rain per year. The rainy season begins in April but earlier rainfalls are not rare. The moisture-laden winds from the Atlantic Ocean bring the rains delivered from cloudbursts, accompanied by intense electrical storms and high winds. By June or July rain falls almost continuously but less intense. (Fraser et al, 1998). The upper limits of the mountain (over 3050m) are swept by North East trade winds, which have a night temperature slightly under freezing point and little more than 5°C during the day. This forms a “condenser” on the top of the mountain. The warm air is rapidly cooled thus causing a fog and cloud which surrounds Buea and the villages on and above the 900m (Zielewska, 2004). Air temperature is more or less constant throughout the year. Mean daily temperature drops 1 or 2°C in the wet season, but diurnal temperature variation is greater than seasonal differences (Fraser et al., 1998). Temperatures on the mountain decrease with altitude (0.6°C per 100 m height difference). E.g. Temperatures at Fako Mountain lodge (2800 m asl) varies between 5°C (Min) and 16° (Max). At the summit temperatures go down to 1-5°C. Strong cold winds are blowing on the upper part of the mountain. The dry season runs from November to March, and is ideal for hiking in the Park without much rain, though visibility is partly negatively impacted between January and March when the Harmattan winds from the Sahara bring dust. However the summit stands over the dust which forms a layer between 1000 and 3000 m. Best visibility and still apt for hiking are the transition periods from the rainy to dry season October/November/December and from dry to rainy season April/May/June.

 

Landscape

 

Landscape And Vegetation Types

 

The Mount Cameroon Region offers an outstanding diversity of landscapes, vegetations, habitat types and ecosystems: from lowland and mountain rainforest to grasslands and volcanic “lunar” landscapes. With clear atmospheric conditions you have splendid views to Bioko island (Equatorial Guinea) just 40 km over the ocean with the volcano Pico Basile (3011 m) and to all the coast line between Debundscha, Limbe and the mangroves up to Douala.

It can be guaranteed to the visitor that on the mountain he is discovering astonishing new surroundings and sceneries qualified by some as majestic, magic , mystical. The western slope of Mount Cameroon is the only area in West and Central Africa where there is an unbroken vegetation gradient from evergreen lowland rainforest at sea-level, through montane forest, to montane grassland and alpine grassland near its summit. This link between ecosystems largely accounts for the biological diversity of the region. There are five vegetation types on the mountain, all of which provide different experiences for visitors:

 

View on the bay of Limbe 
On the way to Mann Spring –view on Mt Etinde and Bioko Island
LowlandEvergreenRainForest
 

Lowland Evergreen Rain Forest (0 -800m)

The lowland forest occurs in patches in the western slopes of the mountain and is heavily affected by human activities (agriculture and illegal timber exploitation). This species-rich forest consists mainly of evergreen tall trees (25 – 35 m) forming a dense and fairly continuous canopy with large emergent trees poking through it. Many emergent and canopy trees have buttresses and a number of small trees and shrubs bear their flowers directly on the trunk or larger branches. This flower habit known as cauliflory, as well as buttressing are highly characteristic of the lowland rainforest. Beneath the tree layer, are shrubs, tall herbs and a ground layer consisting of seedlings, low-herbs and ferns. The lower trees are usually connected by large lianas.

Omphalocarpum procera – a case of cauliflory The seed of the fruits are used for feet rattles in traditional dances
SubMontaneForest

 

Sub-montane Forest (800- 1,600m)

The lowland forest usually gives way gradually to sub-montane vegetation between 800-1,600m, dominated by either a closed canopy forest or a discontinuous canopy forest with considerable patches of natural meadows and scrubs. It is characterised by a low canopy (20-25m) with scattered large trees (up to 35m tall). Although, less diverse and less tall than the lowland forest, it is richer in epiphytes and tree ferns. Because of the heavy mist, the greater cloud cover and the consequent high humidity that envelop this forest for long periods, the sub-montane forest is also called “cloud forest” or "Mist forest". Such conditions allow for the development of a rich epiphytic flora. Above 1,500m trees are intensively covered by bryophytes, mosses, lichen and vascular epiphytes including ferns and orchids. The herb layer is also very rich in terrestrial ferns. Characteristic species are tree ferns (Cyathea manneana and C. camerooniana) and large strangler figs. Patches of meadows and scrubland dominated by dense tall herbs (2m) with scattered shrubby trees and tree ferns also occur in the sub-montane forest especially on fairly deep soils. They are usually dominated by Hypselodelphys scandens which are often associated with species of Aframomum and Marantochloa. This type of forest main present on the western slope is also called “Elephant bush” by the local community. It is much favoured and maintained by the presence of elephants on the mountain. In the absence of Hypselodelphys, areas of scrubland are dominated by a dense stand of scarcely woody monocarpic Acanthaceae (Mimulopsis solmsii, Oreacanthus mannii and Brillantaisia sp.), and Labiatae (Plectranthus insignis), dense tall herbs (e.g. Aframomum spp. and Melanthera scandens), and by tangles of herbaceous climbers. Part of the forest at lower altitudes outside the park (Buea) transformed into agricultural use.

Sub-montane forest with tree fern (Cyathea manneana)
                           Strangler fig (Ficus spp)
MontaneForest

 

Montane Forest (1,600-2,500m)

The transition from sub-montane to montane forest is gradual and occurs around 1,600-1,800m. Although well developed, the montane forest is of limited extent and gives way either abruptly or with a transitional belt of fire-resistant scrubs to montane grassland at about 2,000-3,000m. The montane forest is species-poor, apparently drier and has less cloud cover. The forest is more open and irregular in structure, with either one or two layers of trees, both very irregularly distributed. The trees are smaller, 15-20m high and are characteristically festooned with epiphytes and mosses. Typical tree species are: Schefflera abyssinica, S. mannii, Prunus africana, Rapanea melanophlaeos, Xymalos monospora, Hypericum revolutum, Clausena anisata, and Nuxia congesta.

View on the canopy of the mountain forest with Mt Etinde in the background  
 Tree covered with lichen at the edge of forest and grassland
MontaneGrasslandAndShrubs

 

Montane grass land and scrubs (1,800-3,000m)

The montane grassland is dominated by tall grasses (1-2m high) with scattered stunted, gnarled and dwarfed trees, and enclaves of woodland or thicket in gullies and rocky areas which act as natural fire breaks. This montane tall-grassland is always very colourful with many beautiful flowering herbs and shrubs. Most of this zone, as well as the subalpine zone are subject to frequent burning. This vegetation type is dominated by tall tussock grasses of which Loudetia camerunensis, Andropogon lima and Pennisetum monostigma are the most characteristic. They are commonly associated with Indigofera alatipes, Cyanotis barbata, Trifolium simense, Kyllinga odorata, Hypoxis camerooniana, Swertia abyssinica, Holothrix tridentata, and Habenaria spp. Occasionally, scattered small trees or shrubs such as Agauria salicifolia, Myrica arborea, Pentas schimperiana, Hypericum lanceolatum, Adenocarpus mannii, Philippia mannii, and Satureja robusta occur here and there in gullies and bushes. The montane scrub does not form a continuous belt, but forms blocks or patches separated by grassland with scattered shrubs. Although, it is usually confined to the forest fringe (forest/grassland boundary), and especially protected gullies and craters, isolated fragments of scrubland also occur as high as 3,500m. The montane woodland is poorly developed and the vegetation is rather open with fairly even or discontinuous canopy of small trees. Near the forest edge, the trees become dwarf and stunted, and do not usually exceed 10-15m height. The forest is also much drier and receives a low rainfall. As a result, montane scrub is very prone to damage by fire. Because this forest is extensively degraded by fire, montane scrub and forest edge species are common. They include Hypericum lanceolata, Maesa lanceolata, Agauria salicifolia, Myrica arborea, Lasiosiphon glaucus and Philippia mannii.

Grassland with the “mountain flower “(Helichrysum mannii)
                                   Agauria salicifolia (“Mbeli” in Bakweri )
SubAlpinePrairie/Grassland

 

Sub-alpine prairie/grassland (3,300-4,070 m)

The sub-alpine grassland is dominated by short very thick dense tussock grasses, with isolated patches of dwarf and gnarled shrubby trees, cushions of mosses and thick crust foliose and fruticose lichen. Grasses have narrow enrolled leaves and almost all plants are xerophytes. Common grass species include Deschampsia milbraedii, Agrostis mannii, Koeleria cristata, Festuca abyssinica, Bulbostylis erratica, B. capillaris, Andropogon distachyus, A. lima, A. mannii, A. amethystinus, Sporobolus montanus, Tripogon major, Silene biafrae, Aira caryophyllea, and Crepis camerooniana. Trees are usually absent, Adenocarpus mannii and Blaeria mannii occur as high as 3,500m. Near the summit area above about 3,600m, the vegetation is sparse and the area has the appearance of a semi-desert. The substratum is highly porous consisting of cindery lava flows of recent origin. These harsh conditions account for the paucity of vascular species around the summit. Colonisation is sparse, clear dominants are lacking, and only patches of mosses, lichens, short tuffs of the grass Pentaschistis mannii, and dwarf shrubby Ericaceous species (less than 15cm tall) such as Blaeria mannii and Philippia mannii, which are well adapted to withstand the extreme and prolonged desiccation can establish themselves.

Mosses and lichens on lava above 3,800 m altitude

EcologicalSuccessionOfLavaFlows

 

Ecological succession of lava flows

On lava, different phases of the succession of plant formations can be observed, from pioneer species as algae, lichen, mosses, ferns and orchids. Later other more complex herbs and scrubs install at from 45 years onwards also small trees develop.

Lava flow from 1999 at Bakingili – Photograph 2006
Same lava flow from 1999 at Bakingili – Photograph 2017

 

Lava flow having passed through the forest and vegetating
Old lavaflow with unknown age with trees in the grassland
Flora

 

Flora

Mount Cameroon is known for its exceptional plant diversity and high number of endemic species with over 2,435 species of plants in more than 800 genera and 210 families (see S. Cable, M. Cheeks 1998 : the plants of Mount Cameroon – a conservation checklist). Of these 49 plant taxa (species, subspecies, and varieties) are strictly endemic to Mount Cameroon and 50 are near endemic plant species (also occurring in Bamenda Highlands, Oku, Kupe, Korup, Obudu Plateau and Bioko –Almost all of the plant families endemic to tropical Africa such as Huaceae, Medusandraceae, Lepidobotryaceae, Octocknemataceae and Hoplestigmataceae are found on Mount Cameroon and the surrounding foothills. The second larges flowering plant family on the mountain after the Rubiaciea with 261 species are the Orchidacea with 147 species. The explanation for the high level of endemic plant species and the fascinating pattern of vegetation stems from the fact that Mount Cameroon is most likely part of an important Pleistocene refuge (Maley 2002). In the photos below we present some of the characteristic and common plant species on the mountain, from the grassland area:

Hypericum spp  
Adenocarpus mannii

 

Mountain Mint (Saturea robusta)
Helichrysum mannii

 

Crassula vaginata 
 Erica mannii

Veronica mannii (close to summit)   
Senecio purpureus
 
Polystachia alpina
Brownleea parviflora

Begonia spp
Utricularia mannii  
Fauna

 

Fauna

BigMammals

 

Big mammals

Mount Cameroon National Park has been classified “exceptional priority site” for the conservation of the Nigerian-Cameroon Chimpanzee (Pan troglodytes ellioti) EN, the most endangered of the four recognized chimpanzee subspecie (see Regional Action plan for the conservation of the Nigerian-Cameroon Chimpanzee, Morgan B.J. et al. 2001). Other endangered and threatened primates are the Drill (Mandrillus Leucophaeus leucophaeus) EN, Preuss’ guenon (Allocchrocebus preussi preussii) EN and Red-eared monkey (Cercopithecus erythrotis camerunensis) VU. Present are also the Red-capped Mangabey (Cercocebus torquatus) VU, Crowned Guenon (Ceropithecus pogonias) VU, Putty nosed monkey (Cercopithecus nictitans) LC, and Mona Monkey (Cercopithecus mona) LC. As nocturnal primates, also present are several species of Galago and a potto (buThe park hosts forest elephants (Loxodonta africana cyclotis) on its southern and western flank, probably populations living most high in altitude in the world, being observed up to 2000 m altitude. Most prominent to be seen on the mountain, specially in the savannah is the bush bock (Tragelaphus scriptus). Other big mammals present are the Bay duiker (Cephalophus dorsalis), Blue duiker (Cephalophus monticola), Yellow backed duiker (Cephalophus sylvicultor), and the Red river hog (Potamochoerus porcus). Most of the animals are present in the sub-montane and montante forests. Read less

 
Nigerian-Cameroon Chimpanzee (Pan troglodytes ellioti
Preuss’ Guenon (Allocchrocebus preussi preussii)

 

Forest Elephant (Loxodonta Africana cyclotis
Bush bock (Tragelaphus scriptus)
SmallMammals

 

Small mammals

Under small mammals on the mountain it is worthwhile to mention at least 22 species of bats. The bats can be best observed at some bat caves. Other small mammals which are strictly endemic to the mountain are Eisentraut’s Shrew (Crocidura eisentrauti), Arrogant Shrew (Sylvisorex morio), M Cameroon Brush-furred Rat (Lophuromys roseveari) and as near-endemic the Cameroon Praomys (Praomys morio).

Some bats in Mount Cameroon National Park
Birds

 

Birds

The sub-montane and montane habitats are part of the Cameroon Mountains Endemic Bird Area (EBA). Twenty of the 28 restricted-range bird species of the EBA have been recorded on Mt Cameroon, including the two strictly endemic species Francolinus camerunensis and Speirops melanocephalus (IUCN/WWF, 1994). So far a total of 220 species of birds has been recorded from the on-going surveys. Out of these, eight are threatened. These include the Mount Cameroon Francolin (Francolinus camerunensis), the Black capped Speirops (Speirops lugubris) and the Mount Cameroon Rough-Wing Swallow (Psalidoprocne spp.). All these birds are unique to the Mt Cameroon Region. The Cameroon Blue-headed Sunbird (Nectarinia oritis) is endemic while the Grey-necked Picathartes (Picathartes oreas) is rare (Hořák 2014).

Mt Cameroon Francolin (Francolinus camerunensis)  
Mountain Robin Chat (Cossypha isabellae)

 

Green Crombec (Sylvietta virens) at Fako Mountain lodge 
African Stone chat (Saxicola torquatus) in the grassland
ReptilesAndAmphibians

 

Reptiles and amphibians

Eighty-six (86) reptile species, representing more than one third of the reptile fauna known in Cameroon, are found in the Mt Cameroon area, making this site among the richest in the country. Lowland forest had the greatest number of species (58), followed by submontane forest (45), montane forest (21), and marine (4) species. A number of rare or little known reptiles are there to be found like the skink Lacertaspis gemmiventris and the blind snake Typhlops decorosus. Mt. Cameroon appears not to have any strictly endemic reptile species, but it hosts two regional Cameroon highland endemics, the Cameroon two horned Chamaeleon (Triocerus montium) and Lacertaspis gemmiventris (Gonwouo et al. 2007). The reptiles represent about 30% of the estimated Cameroon reptile fauna out of 283 species. Amphibian species of conservation concern include an endemic toad (Werneria preussi) and near-endemics, such as the four-digit toad (Didynamipus sjostedti), Tandy's small tongue toad (Werneria tandyi) and a frog (Arthroleptis bivittatus) (Birdlife International 2014, IUCN 2014). Recently a frog species collected in 1906/7 by O. Rau and C. Feldmann at Bibundi was re-examined and named Hylambates rufus aubryioides (Köhler 2009). The species has not been recorded after this record.

Pygmee Chamaeleon (Rampholeon) 
Two horned Mountain Chameleon (Triocerus montium)
Insects

 

Insects

Mount Cameroon harbours many thousands of insects and other arthropods species, unfortunately this biodiversity is still mostly unexplored. Butterflies are indisputably the best known group, with over 320 species found by the recent survey (Tropek et al., unpublished data). Three of these species (Ceratrichia fako, Charaxes musakensis, Lepidochrysops liberti) are endemic to Mount Cameroon only, all of them occur in montane and submontane forests only. Over 20 other species are sub-endemic, i.e. occurring in some other mountains of Cameroon, Nigeria or Bioko as well. The recent description of C. fako (bearing the local name of the mountain: Fako) and L. liberti (Sáfián & Tropek 2016) proves that even such favourite group can still be hiding some local surprises. The local biodiversity of moths is much higher, but also much less known. The recent survey revealed already almost two thousands of moth species, many of these previously unknown for science. At least dozens of these are considered as endemic for Mount Cameroon, for instance Geraldocossus durreli, Alucita fokami, A. besongi or A. janeceki belong among these. In the recent years, at least 12 new species have been described from Mount Cameroon (Przybyłowicz 2013, Yakovlev and Sáfián 2016, Ustjuzhanin and Kovtunovich 2016, Ustjuzhanin et al. 2018), numerous others are under description now. Currently, details from biology and habitat needs of individual species of butterfly and moths, as well as structure of entire communities are extensively studied, you can follow some news in www.insect-communities.cz. There are no systematic studies on other groups of invertebrates, but at least a goblin spider Triaeris fako is consider as an endemic species.

Beautiful male of Cymothoe sp butterfly (©Jan Mertens)
Euphaedra permixtum butterfly (©Jan Mertensother)

 

Nonidentified beetle
Nonidentified katydid (Tettigoniidae) mimicking a leaf (©Jan Mertens)
Culture

 

Culture

Mount Cameroon is very closely linked to the culture of the Bomboko and Bakweri people. Its native name Fako in Bakweri language and Mongo ma Loba ("Pillar of God") in the Douala language. The local people have shrines on the mountain and inside the National Park. They are in relationship with “Efasa Moto”, the God of the Mountain, a powerful being, half human and half rock; generous and bountiful but severe to transgressors who are greedy and inconsiderate of the environment. The Totem of the local people is the elephant “Njoku” in Bakweri language, the member of the secret “Male” society, the « Vato va njoku », can transform in elephants and have “their” elephant in the mountain (see also cultural attractions around the park). Another male secret society is the “Nganya” also having some animals as totems. On the female side there is the “Liengu” society. The Bakweri use quite a number of plants for traditional medicine and rituals. For example the dried and grounded bark of the Mbeli tree from the grassland is used in a ritual to express unity between family members of the maternal lineage. The local population is supporting the efforts for the protection of the park and the conservation of their patrimony with all its natural and cultural values. “According to Bakweri oral tradition, Efasa-Moto is the male component of the Liengu la Mwanja or the legendary "Mammy Water." It is said that after an agreement between the two, Efasa-Moto chose to live in the mountain and while the Liengu la Mwanja remained at sea. It is believed that Efasa-Moto and Liengu la Mwanja are the greatest spiritual figures that the earth has ever known. Physically, Efasa-Moto's is described as being divided vertically from top to bottom in a strange mixture of half human and half stone, and yet shaped in the form of a man giving a complete picture of a goat standing on its hind legs. Liengu la Mwanja on the other hand is a beautiful looking woman with an oval-shaped face, an enchanting smile with a love gap-tooth, overflowing hair of dark wool resembling a beautiful Indian lady with high and well curved hips. Efasa-Moto lives in the mountain alone. He maintains a rich healthy sugar cane plantation. His visitors can eat the sugar cane on the spot but cannot carry any away. It is said that the sugar cane is has an unforgettable sweetness. Efasa-Moto is also said to be the mountain's spiritual protector. In times of old, dead albinos were abandoned on the mountain as offerings of appeasement to the mountain god so that he could continue to bless the inhabitants at the foot of the mountain. Some elders say Efasa-Moto helped the Bakweri defeat the Germans in the Battle of Bokwango of 1891. The elders add that the Bakweri eventually lost the war because they betrayed Efasa-Moto's trust.”

Bakweri Nganya dance (The RECORDER Newsline)
“Male” elephant dance in Bwassa village
HistoricalElements

 

Historic elements

The first Europeans climbing on the summit were Richard Francis Burton, a british explorer, linguist (he spoke 29 languages), poet, orientalist and many others, and Gustav Mann, a German Botanist, working for Kew Gardens in Britain. They climbed the mountain in 1861. Gustav Mann was the first plant collector of Mt Cameroon. He visited Mt Cameroon three times between 1861 and 1862 and collected hundreds of specimens. 349 tropical plants are named after Gustav Mann, having the surfix “mannii”. He is commemorated also with the names of several genera. The spring of Mowe (Bakweri name) is today commonly named Mann’s Spring. The first European woman to climb the mountain was Mary Kingsley in 1895 (see her chapter on the trip in the book “Travels in West Africa”). The three huts built on the “Race of Hope” trail were built during German Colonial Period by the “Deutsch Kameruner Alpenverein” (German-Cameroon Mountaineer Association) and were called Mosake (Hut1), Johann Albrecht Hütte (Hut2), Herzogin Elisabeth Hütte (Hut 3).

Thumbnail Image 1                             Gustave Mann
Thumbnail Image 1                         Richard Francis Burton
Thumbnail Image 1                                    Mary Kingsley