Maluku Islands - Biota and Environment

Biota and Environment

Biogeographically, all of the islands apart from the Aru group lie in Wallacea, the region between the Sunda Shelf (part of the Asia block), and the Arafura Shelf (part of the Australian block). More specifically, they lie between Weber's Line and Lydekker's Line, and thus have a fauna that is rather more Australasian than Asian. Malukan biodiversity and its distribution are affected by various tectonic activities; most of the islands are geologically young, being from 1 million to 15 million years old, and have never been attached to the larger landmasses. The Maluku islands differ from other areas in Indonesia; they contain some of the country's smallest islands, coral island reefs scattered through some of the deepest seas in the world, and no large islands such as Java or Sumatra. Flora and fauna immigration between islands is thus restricted, leading to a high rate of endemic biota evolving.

The ecology of the Maluku Islands has fascinated naturalists for centuries; Alfred Wallace's book, The Malay Archipelago was the first significant study of the area's natural history, and remains an important resource for studying Indonesian biodiversity. Maluku is the subject of two major historical works of natural history by Georg Eberhard Rumphius: the Herbarium Amboinense and the Amboinsche Rariteitkamer.

Rainforest covered most of northern and central Maluku, which, on the smaller islands has been replaced by plantations, including the region's endemic cloves and nutmeg. The Tanimbar Islands and other southeastern islands are arid and sparsely vegetated, much like nearby Timor. In 1997 the Manusela National Park, and in 2004 the Aketajawe-Lolobata National Park have been established, for the protection of endangered species.

Nocturnal marsupials, such as cuscus and bandicoots, make up the majority of the mammal species, and introduced mammals include civets and wild pigs. Bird species include approximately 100 endemics with the greatest variety on the large islands of Halmahera and Seram. North Maluku has two species of endemic birds of paradise. Uniquely among the Maluku Islands, the Aru Islands have a purely Papuan fauna including kangaroos, cassowaries, and birds of paradise.

While many ecological problems affect both small islands and large landmasses, small islands suffer their particular problems. Development pressures on small islands are increasing, although their effects are not always anticipated. Although Indonesia is richly endowed with natural resources, the resources of the small islands of Maluku are limited and specialised; furthermore, human resources in particular are limited.

General observations about small islands that can be applied to the Maluku Islands include:

• a higher proportion of the landmass will be affected by volcanic activity, earthquakes, landslips, and cyclone damage;
• Climates are more likely to be maritime influenced;
• Catchment areas are smaller and degree of erosion higher;
• A higher proportion of the landmass is made up of coastal areas;
• A higher degree of environmental specialisation, including a higher proportion of endemic species in an overall depauperate community;
• Societies may retain a strong sense of culture having developed in relative isolation;
• Small island populations are more likely to be affected by economic migration.