Conservation status of succulents
Although a comprehensive listing of the conservation status of succulent plants of Somalia has not yet been prepared, IUCN categories have been applied to a number of succulent species, especially in the genera Euphorbia and Aloe. WCMC holds records of 61 nationally threatened succulent species for the country. Data sheets on Euphorbia cameronii and Whitesloanea crassa are included in the IUCN Plant Red Data Book (Lucas and Synge 1978). The genus Pseudolithos is endemic to Somalia. All four species of this genus are rare and severely threatened. In general, many of the asclepiads of Somalia are considered to be exceedingly rare (Kuchar 1986). The low representation of stapeliads in herbarium collections may be because the small populations initially located have been decimated by intensive grazing and erosion (Kuchar 1986).
Four centres of endemism and plant diversity for Somalia are given in Centres of Plant Diversity (WWF and IUCN 1994). These are Hobyo, the Cal Madow mountain range, the fixed dune vegetation in southern Somalia, and the Nugaal Valley.
Hobyo — The area around Hobyo (Obbia) in the Mudug Region of central Somalia, covering around 3000 km2, consists of a coastal plain with dunes and areas of limestone pavement, particularly in the north; a low limestone escarpment running more or less parallel to the coastline; and a low plateau further inland. The limestone escarpment reaches about 440 m south-west of Hobyo. It is dissected by deep gorges which run approximately east to west. The gorges contain seasonal streams. The vegetation of the coastal plain is open and treeless with a low vegetation of grasses, herbs, and shrublets. The limestone escarpment is covered with a species-rich Acacia-Commiphora bushland and the inland plateau also has bushland and woodland dominated by species of Acacia and Commiphora. The area is still relatively inaccessible and in need of further botanical study. Succulents are frequent. The threats to the flora are not particularly severe at present, although the effects of over-grazing and cutting of woody vegetation for are damaging in some places. Fortunately, the most botanically interesting vegetation, that of the dunes and limestone gorges, is still largely intact. Parts of the area have been proposed as a Game Reserve.
Cal Madow— As mentioned above, the Cal Madow (A1 Medu) mountain range, a large area which extends right up to the north-east corner of Somalia, is an internationally important centre of plant endemism. This remote area is relatively sparsely populated and was apparently untouched by the recent war. The region consists of a coastal plain bordering the Gulf of Aden, locally known as the "Cuban", and an uplifted limestone plateau lying to the south and dipping to the south-east.
The plateau scarp reaches 2416 m at Shimbiris (the highest point in Somalia), to the north-west of Ceerigaabo.
The vegetation of Cal Madow varies greatly according to altitude and rainfall and includes coastal plain of desert or semi-desert, with little or no vegetation; the subcoastal zone with sparse to dense, primarily woody vegetation; slopes of the escarpment covered by a macchia-like evergreen or semi-evergreen scrub which, at higher elevations, grades into remnants of Juniperus forest degraded by logging. To the south of the escarpment, vegetation consists of severely degraded open woodlands.
Examples of phytogeographically interesting succulent species present in Cal Madow include Aeonium leucoblepharum and Euphorbia balsamifera. Several succulent Euphorbia spp. are endemic.
The most interesting vegetation along the escarpment is still largely intact and threats to the flora are not particularly severe at present. Daalo Forest Reserve, to the north of Ceerigabo, and the surrounding mountain area have been proposed for protection as a national park. However, at present there are no functioning nature reserves in Somalia.
Fixed dune vegetation in southern Somalia — This vegetation supports xerophytes and succulent species of many genera. Large, fixed and vegetated dunes occur in southern Somalia along the Indian Ocean from south of Hobyo to just south of the border with Kenya. These are mostly 10-15 km wide and between 20 and 60 m high. Some dunes have been deprived of their vegetation by overgrazing and are moving inland. The vegetation consists of Acacia bushland. There are more than 200 vascular plant species, with over 20 strict endemics and a number of endemic subspecies. Some of this vegetation should be protected by the proposed Lag Badana Bushbush National Park.
Nugaal Valley — An arid area along the Wadi Nugaal, about 250 km long. The western part consists of massive deposits of gypsum and anhydrites, while the coastal part is mainly limestone. The vegetation consists of open semi-desert grassland or bushland. The succulent flora is particularly rich with a number of local endemics. Priority sites associated with the Wadi Nugaal include the gypsum hills around Las Anod where the sparse degraded vegetation supports a rich endemic succulent flora with Aloe inermis, Dorstenia gypsophila, Adenia aculea ta, Raphanocarpus stefaninii, Euphorbia columnaris, Pterodiscus, and Caralluma spp. The Las Anod National Park has been proposed by Bally and Melville (1973) to protect fine scenery, rich and varied flora, and the Somali wild ass (Equus asinus somalicus). They also suggest that a fenced floral reserve be created for Euphorbia columnaris. The limestone plateau to the north of Eil is another area rich in succulent plants including many endemics and has been proposed as a national park by Bally and Melville (1973).
Other priority succulent sites include:
• Gaan Libah Forest Reserve — Aloe jucunda. Aloe hildebrandtii, Euphorbia abyssinica, Kalanclwe spp., Echidnopsis spp.; proposed as a national park by Bally and Melville (1973).
• Sheikh Pass area in the Golis Mountains — rich in endemic species; Whitesloanea crassa, Pseudolithos cubiformis, Euphorbia phillipsiae, Aloe somaliensis. Aloe hemmingii, Euphorbia inculta, Edithcolea grandis, Monadenium ellenbeckii, Kleinia gunnisii, and Echidnopsis cilia ta.
• Molidera Hills — two gypsum hills 58-62 km south of Erigavo on the road to El Dab; Aloe molederana. Pelargonium christophoranum, Dorstenia gysophilu, and Dracaena ombet; floral reserve suggested by Bally and Melville (1973).
• Bulo Burti — limestone ridge with rich flora including Monadenium stellatum; floral reserve suggested by Bally and Melville (1973).
Somalia lacks any organised protected area system to conserve its critical sites. Of the conservation areas established and proposed since 1969 only Balcad and Alifuuto Nature Reserves are currently functional, and plans have been prepared for the proposed Lag BadanaBushbush National Park. The legal establishment of all conservation areas in Somalia would result in more than eight per cent of the total area being covered. In addition, there are 27 'protected forests' and grazing reserves established to protect grazing lands (WCMC 199 1).
The author would like to thank Mike Gilbert and Susan CarterHolmes for the provision of information and suggestions for this account; the Plant Conservation Programme of the National Museums of Kenya has also provided valuable information. The Protected Areas Unit of WCMC is also thanked for the provision of information.
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