When you think of
something being endangered, you probably automatically think of animals. In the
entire world, there are about 5,000 endangered species of animals, and despite
the importance of protecting these endangered animals; there is also an importance
in protecting endangered trees all over the world.
Grandidieri’s Baobab is an 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; is the strangest and most magnificent of
them all. They have massive cylindrical trunks, up to three meters across and
twenty five meters height, 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.
Grandidier’s baobab used to inhabit dry, deciduous forest, especially near
seasonal rivers or lakes. However, today it is mainly found in open,
agricultural land or degraded scrub
Status: Classified as Critically Endangered by the IUCN Red
List
Population: In 2011 further data was gathered on Grandidier’s
baobab populations and condition. A total of 1,310 Grandidier’s baobabs were
measured and exploitation level recorded.
Biology: The long-lived Grandidier’s baobab 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. It is pollinated by nocturnal mammals, such as
fork-marked 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.
Grandidier’s baobab bears ripe fruit in
November and December. Unlike the baobabs of Africa and Australia, it appears
that the seeds of the tasty fruit are not dispersed by animals. Lemurs are the
only living animals on Madagascar that are capable of acting as seed
dispersers, yet this has never been documented. In the past however, this could
have been very different. There are several species that became extinct since
human colonisation of the island, 1,500 to 2,000 years ago, that could very
likely have been dispersers of the seeds. This includes species of primates
that were thought to be similar to baboons, and the heaviest bird that ever
lived, the elephant bird, which had a powerful beak that could have opened
large fruit. Today, water may be the means by which the seeds are dispersed.
On the tropical island of Madagascar, a
lack of water can sometimes be a problem for its inhabitants. It appears that
the baobab overcomes this by storing water within the fibrous wood of the
trunk, as the tree’s diameter fluctuates with rainfall.
Threats: Grandidieri’s is the most heavily exploited of all
the Malagasy baobabs. The seeds and the vitamin C-rich fruit pulp are eaten
fresh, and cooking oil is extracted from the oil-rich seeds. The fruit is
either collected from the ground, or wooden pegs are hammered into the trunk so
the tree can be climbed to collect the fruit. The thick bark of the baobab is
composed of tough long fibres that can be used to make ropes, and the majority
of trees bear scars from where the bark was cut from ground level to about two
meters to obtain this material. The spongy wood is comprised of sheets of fibre
that are collected from dead or living trees, dried in the sun and sold for
thatch. Most of these varied uses do not involve the tree being killed, and
thus are unlikely to pose a great threat to the baobab. 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 Madagascar baobab to
reproduce, which may have devastating consequences for its survival.
Conservation: Numerous non-governmental organisations and
scientists, along with the Malagasy government, realise 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. 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.
References:
http://en.wikipedia.org/wiki/Adansonia_grandidieri
http://www.arkive.org/grandidiers-baobab/adansonia-grandidieri/
http://www.globaltrees.org/tp_grbaobab.htm
http://www.fauna-flora.org/species/grandidiers-baobab/
http://www.iucnredlist.org/sotdfiles/adansonia-grandidieri.pdf
