#Natureology Species of the Day – Grandidier’s baobab (Adansonia grandidieri)
Grandidier’s baobab (Adansonia grandidieri) imposing and unusual tree occurs only on the island of Madagascar, where it is threatened by the encroachment of agricultural land. There are eight species of baobabs, six of which are endemic to Madagascar are nearly all threatened and endangered with extinction because of deforestation and exploitation by local communities. .
Grandidier’s baobab is the strangest and most magnificent of them all the baobab trees. They have massive cylindrical trunks, up to three meters across, covered with smooth, reddish-grey bark. At certain times of the year the flat-topped crowns bear bluish-green palmate leaves, dark brown floral buds or spectacular flowers with white petals .
The large, dry fruits of the baobab contain kidney-shaped seeds within an edible pulp. It probably occurred in dry deciduous forest, frequently close to bodies of water, but mature trees are now largely found in degraded agricultural lands where regeneration is poor.
Grandidier’s baobab bears ripe fruit in November and December and is in leaf from October to May, and flowers between May and August . The flowers, said to smell of sour watermelon, open just before or soon after dusk, and all the pollen is released during the first night . I
t is pollinated by lemurs. They move through the canopies, inserting their snouts into the white flowers and licking nectar from the petal bases, resulting in pollen being deposited in the lemur’s face. Baobab overcomes this by storing water within the fibrous wood of the trunk, as the tree’s diameter fluctuates with rainfall.
Grandidier’s baobab occurs in south-western Madagascar and is restricted to five locations distributed between Lac Ihotry, near Morombe, and Bereboka, north of Morondava.
Grandidier’s baobab is listed as Endangered by the IUCN Red List. Adansonia grandidieri is the most heavily exploited of all the Malagasy baobabs . This species is threatened by fire, slash-and-burn farming, over-grazing (which inhibits regeneration) and damage from bark removal by local communities. Over-grazing and fire are the main recorded threats, but little is known about the levels of bark and fruit collection. The greatest threat to this species has come from the transformation of its forest habitat into agricultural land. Within these disturbed habitats, there is a noticeable lack of young trees. Fires, seed predation, competition from weeds and an altered physical environment might be affecting the ability of the Madagacar baobab to reproduce , which may have devastating consequences for its survival.
Conservationist and non-governmental organisations , along with the Malagasy government are realizing the importance of conserving the unique biodiversity of Madagascar and are working to protect this magnificent island and its diverse fauna and flora . One measure, from which Grandidier’s baobab is likely to benefit, is the designation of protected areas and reforestation programmes involving local communities.
In 2003 the President of Madagascar vowed to triple the amount of protected areas ; a pledge that won’t only help the magnificent giant baobab, but also the Malagasy people, whose livelihoods depend on the preservation of their watersheds and forests. Community awareness raising and education in local schools about the importance of the tree is also a priority. Formal conservation of the remaining wild population of Grandidier’s Baobab will be another essential step towards protecting the species.