Madagascar

Gerald Durrell described Madagascar as being

'shaped like a badly made omelette lying off the east coast of Africa but containing, as a properly made omelette should, a wealth of good things inside it'.

This particular omelette is the size of France and Switzerland put together.

Leaving the mainland

Madagascar was once sandwiched between India and Africa. Then it split from the mainland, between 100 and 180 million years ago, carrying with it a wealth of wildlife from the African continent.

Until 40 million years ago, before it became too isolated, animals could reach Madagascar by floating across from the surrounding continents on rafts of vegetation.

New species evolving

Once marooned on this young island, the plants and animals evolved over time into unique species. Around 80% of all its species are endemic, meaning that they are found nowhere else in the world.

Few large predators made it to the island, so new species could evolve to fill different niches. The aye-aye, for example, evolved to take advantage of the gap in the insectivorous market. Its long, slim finger enables it to hook out insect larvae hiding in crevices in wood.

Lemurs – endemic primates The aye-aye belongs to an endemic group of primates known as the lemurs. There were over 40 species of primate adapted for life throughout Madagascar. Since the arrival of humans more than 10 species are now extinct.

The human population

Madagascar's wildlife treasure chest is matched for uniqueness by the variety of the people, the first of whom settled on the island in AD 500. It is now a melting pot of colours and creeds mainly from Africa, Asia and Arabia, who have themselves evolved new cultures and traditions bearing little resemblance to their ancestral homes.

Agriculture – growing rice

A common need for land links together people and wildlife. Traditionally, farming has been the source of human sustenance, with rice being the most common source of food. Growing rice is a way of life, and is integral to the local culture.

Rum is still sprinkled onto the fields before many farmers start their day's work as a mark of respect for the ancestors who first cultivated rice hundreds of years ago. Rice cultivation is the bridge between the present-day Malagasy population and their 'ancestors'.

Reed beds under environmental pressure

Nowhere illustrates the conflict between humans and their habitat better than around the largest freshwater lake on Madagascar, Lac Alaotra.

As each successive year's crops are planted by the villagers of the 32 villages encircling the lake, more of the reed beds that grow in the shallows are destroyed.

Pioneers and building materials

The villagers rely on the reed beds for building materials, and for textiles such as those used in hats, bags and even sieves for separating the rice from the silt and stones.

It is not only people who benefit from the reed beds; the reeds represent the pioneer community in the area, being some of the first plants to take hold in the marshy habitat.

Maintaining the lake habitat

The reeds act as giant sieves, trapping mud and silt washed down the rivers from the deforested hillsides. This makes the lake a sediment-free home for fish and other lake wildlife.

Without the reeds the lake becomes choked with sediment and dries up, taking with it the fish that form a vital part of the people's diet.

Adapted for reed life

Many other species depend on the reeds for survival, including a species of lemur found only around Lac Alaotra, the Lac Alaotran gentle lemur.

Clearly if the reeds go, then so does the gentle lemur.

Human predators

The villagers also hunt the lemur by burning the reeds and driving the animals out into the open where they are caught and killed for food.

After all, where else can the villagers turn for meat when funds are low?

A threatened habitat The biggest single threat to the reed beds is through the loss of land to farming as the area of water-thirsty rice steadily swamps the lake.

This artificial 'ecosystem' of one plant species reduces the opportunities for animals by providing few new niches to colonise. The monoculture rice farms are unable to support the variety of wildlife dependent on a varied reed-bed system for food and shelter.