"As one brown patch on a blue globe Africa is a rather dry island
where white vapours off the surrounding seas shed their rain rather
sparingly." So wrote Jonathan Kingdon in Island Africa in 1990.
Climatic stability in Africa has always been a great rarity;
preserved chiefly in broken necklaces of ancient mountain gems
scattered around the middle of the continent. One such necklace lies
in a crescent form across East Africa. This is the Eastern Arc.
These days the forested mountains of the eastern arc, arranged from
the Taita hills in Kenya to the Udzungwas of southern Tanzania,
certainly look as if they are themselves islands. Island arks upon a
great island; floating above the dusty plains of East Africa. A
flotilla of emerald sailing ships adrift in a soft brown haze. These
mountain 'ships' are ancient indeed. Crystalline remnants of old
Gondwanaland they have survived intact the last 30 million years of
separations and upheavals. Events that have shaped and reshaped the
ancient living face of Africa. And amazingly their climates have
remained quite stable so that on each, their endowment of life,
their nature, has developed separately, each block of life evolving
in isolation from the ancestral forest stock.
Consequently each 'island' is now unique. They are known as 'centres
of endemism', or 'biodiversity hot spots', two dreary modern catch
phrases that do almost nothing to convey the wonderful living beauty
of these treasure-trove forests. Forests which are home to an
astonishing variety of plant and animal species, all of them unique
beings which can be found nowhere else on Earth. And all of which
owe their survival to the climatic stability and amazing complexity
of environments which the mountains have preserved during the past
30 million years and more.
One of the richest areas of all is the Usambara mountains. For it is
in and around this deeply dissected massif that the greatest variety
of species may be found. The plateau of the East Usambaras in
particular provides a variety of mini-climates, different soils and
a wider spectrum of plants and animals than would seem possible in
such a small area, certainly in any more homogeneous setting. The
Usambaras attract a disproportionate share of the ocean rains, as do
the Ulugurus and the eastern slopes of the Udzungwas farther inland.
Yet there are the other mountains and other forests within this
eastern arc. Each one differing slightly in size, in altitude and in
age, in bedrock and in soils. And each of these dimensions of
difference has had a profound influence upon the fauna and flora
living there. Each forest sustains a treasury of rare plants an
animals, preserving living luxuries which until recently have been
woefully neglected by the commercial world of contemporary man. Each
nurtures a mosaic of communities, creating a diversity and
individuality that makes the forests of the islands, coastal hills
and mountains of Tanzania some of the most exciting and important
places in all of Africa.
Neglect of these forests is a sad legacy of an alien, colonial
mentality. Of an obsession with exotic plantations which excluded
the development of community forestry which might have promoted
indigenous trees, their use and values. Over the past twenty years
great efforts have been made and rewards received. Certainly in the
year 2010 Tanzania cannot afford not to be actively conserving these
forests. For once destroyed or severely damaged there is no hope
that they will ever be resurrected or replaced, and a poor country
will have become incalculably poorer. Hope for their preservation
resides in a wider recognition that the most precious bounty
conferred on this land by the blue ocean beyond is not simply fresh
water and baskets of vegetables, not the bright red soils of the
mountains, nor the white sands of the coast, but it is the ancient
forest communities of nature itself, communities that now depend for
their survival upon us; being as they are; scattered, isolated and
vulnerable along East Africa's seaboard and on a few old mountains
inland.
From top: Mazumbai Forest in West Usambara; an arboreal epiphytic orchid sp; Usambara Double-collared Sunbird at Mazumbai Rest House.
NB: All photographs copyright of Martin Goodey Wildlife Photography. martingoodeywildlifephotography.com
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