Forest fires on the Indonesian island of Sumatra are having an impact on residents and animals alike. Authorities have distributed face masks to locals to protect them from the air pollution. But the damage to the island's unique biodiversity is also cause for concern.

Satellite images from NASA reveal the sheer scale of the forest fires burning on the Indonesian island of Sumatra. There are currently more than 330 fires raging in the eastern province of Riau alone. So far, poor visibility has stymied plans to fight the blaze from the air.

Dense clouds of smoke aren't exactly uncommon in Indonesia - during the annual dry season there are often forest fires. But the current blazes appear to be the work of plantation owners, burning wooded areas illegally to clear land for the cultivation of palm oil.

Palm oil is cheap and versatile, and is worldwide regarded as one of the most important vegetable oils. Almost every second product contains it - from edible goods like margarine, chocolate, cakes and biscuits, to hygiene products such as shampoo and body lotion. Palm oil is even used as a biofuel in some car tanks.

The oil palm tree needs a tropical climate and plenty of space to grow, so it thrives best in areas where rainforests also grow. Indonesia and Malaysia are the largest producers of palm oil in the world. The plantations in Indonesia alone cover 9 million hectares - about a quarter of the size of Germany.

Sumatra's forests are among the most species-rich rainforests in the world. Scientists estimate they are home to more than 10,000 species of plants. But it's not clear how long the island's biodiversity will continue to flourish, because in the past two decades no other rainforests in the world have faced such rapid devastation.

The rainforest is also a crucial habitat for an abundance of animal species, such as the critically-endangered Sumatran tiger. Today only several hundred of these tigers remain in the wild. If the destruction of the rainforest continues at the same pace, there's a chance the species will suffer the same fate as the already extinct Java and Bali tigers.

The Sumatran elephant has already been given protection status in Indonesia, but scientists fear the species could still be wiped out in less than 30 years. The environmental organization WWF estimates just 2500 animals make up the remaining population. And the main reason for their decline? Loss of rainforest habitat.

The region's orangutans, which live exclusively on Sumatra and Borneo, are perhaps the only ones who haven't yet been affected by the fires. Sumatra's orangutan population live in remote forests, far away from the areas that are currently burning. That's a good thing, because the animals are already a critically endangered species.

In January, the International Union for Conservation of Nature (IUCN) officially classified the Sumatran elephant as critically endangered on its Red List of Threatened Species after losing half its population in one generation. According to scientists, if current trends continue the elephant subspecies could be extinct in the wild in less than 30 years.

Sumatra is home to some of the largest populations of Asian elephants outside India and Sri Lanka. But today, only an estimated 2,400 to 2,800 of the animals remain in the wild. About 550 live in captivity, in zoos and conservation areas like Sumatra’s Way Kambas National Park, seen here. This number has dropped by around 50 percent from the last population estimate done in 1985.

Partly to blame is habitat loss: the Sumatran elephant has lost nearly 70 percent of its habitat in the past 25 years, leading to local extinctions in many areas. Though Sumatran elephants are protected under Indonesian law, according to the IUCN, 85 percent of their habitats are located outside of protected areas.

Sumatra has seen a major increase in deforestation rate in the last quarter century, losing over two-thirds of its natural lowland forest, the habitat where elephants feel most at home. These areas have been targeted for agricultural conversion, human population growth and industrial use.

Oil palm plantations and the pulp and paper industries are among the main causes of deforestation. In Sumatra’s Riau Province, these industries are behind some of the world’s most rapid deforestation rates; the local elephant population has declined by as much as 80 percent in the last quarter century.

WWF has said an immediate moratorium on the destruction of elephant habitat is needed to ensure the future of the species. The organization has called on the Indonesian government to work with conservation agencies and agro-forestry companies to come up with a conservation strategy, designate protected areas and link them together with conservation corridors.

The Sumatran elephant is just the latest animal to join the growing list of critically endangered Indonesian species, which includes the Sumatran orangutan, the Javan and Sumatran rhinos and the Sumatran tiger. Orangutans, once spread throughout the forests of Asia, are now confined to just two islands, Sumatra and Borneo. Only about 7,500 Sumatran orangutans exist in the wild.

Sumatran rhinos were once widespread in Borneo, but now are only found in the northeast state of Sabah, in Malaysia. A 2005 survey found evidence of at least 13 rhinos in the area; current estimates place their total population at fewer than 25. Habitat loss and poaching are the main threats to their existence.

There have been no confirmed sightings of the Sumatran tiger on any Indonesian island besides Sumatra since 1976. “Unless urgent and effective conservation action is taken these magnificent animals are likely to go extinct within our lifetime,” said Carlos Drews, the director of WWF’s Global Species Program. Author: Martin Kuebler Editor: Holly Fox