To many, the offshore production facilities punctuating the skyline are probably seen as something of an eyesore. However, the divers who have viewed these structures beneath the waves realize that they provide the foundations for a well- established marine ecosystem.

The Platform Environmental Project commenced in early 2003. The objectives were to document the species distribution on the platforms, and develop an understanding of the controlling influences. The team of divers executing the project received training and ongoing technical supervision from the Tropical Research and Conservation Centre, based in Kuching, Sarawak.

Separate survey techniques were developed to address the following:

  • Small Non-Mobile Species (such as small sponges, ascidians and hydroids)

  • Large Non-Mobile Species (for example black corals, large sponges and gorgonians)

  • Fish Species (Reef Dwelling, Reef Associated and Pelagic)

Environmental parameter surveys were combined with historical Brunei Shell Petroleum wave, current and temperature data to assist in developing an understanding of the species distribution.

The project has demonstrated that there is a diverse and well-established ecosystem beneath the platforms. Approaching 100 fish species were photographed and identified. The majority of these are resident, but pelagic species such as trevally and barracuda regularly visit. Hawksbill Turtles are often seen feeding on sponges and soft corals on the bracings. All available sub-stratum is populated by a diverse range of small non-mobile species, and certain platforms are characterized by impressive growth of black coral. A marked vertical zonation is also evident, due to variation in factors such as ambient light levels, salinity and turbidity. Large numbers of juvenile species have been recorded, pointing towards the platforms as being both producers and attractors of fish.

Ultimately Brunei's offshore structures will be decommissioned. Globally, various options exist, ranging from complete removal to leaving in place. However, opinions and legislation are strongly divided with respect to the best course of action.

With several thousand offshore structures worldwide, decommissioning will become an increasingly important issue. This project and others like it will play a role in ensuring that balanced decisions are made, based on all the available evidence.

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