Examining Reefs on a Gradient of Degradation, Malaysia

Tali Vardi

In Malaysia s race to become a fully developed country by 2020, oil palm plantations have replaced primary rain forest across much of the landscape. These changes in land-use have the potential to impact coral reef ecosystems which are hydrologically connected via rivers and over-land run-off. This grant helped support a lead researcher, Katie Cramer, and me to conduct initial dive surveys of sites throughout peninsular Malaysia and Borneo, which have been varyingly effected by deforestation and other land-use alterations. I assisted on seven dives and several snorkeling trips in two general areas Pulau Tioman, 18 kilometers off of southeast peninsular Malaysia, and Abdul Rahman National Park in northeastern Borneo (in the state of Sabah, Malaysia). In addition, we examined land use patterns and water quality conditions along the Kinabatangan River, the longest river in Borneo, located on the eastern coast of Sabah.

We visited five reef sites off the northwest (leeward) side of Tioman Chebeh Island, Batu Malang, Labas Island, Kador Bay, and Fan Canyon (see below). Because Tioman is relatively far from the mainland (18 km) and has undergone little land conversion, we expected the reef to be in good condition, and that is what we found. Diversity of inverts, especially nudibranchs, was high. Coral cover on reefs was as high as 80%. The reef fish population was diverse; though large fish were rarely observed. It is important to keep in mind that a relatively healthy reef is what you expect when you utilize dive tour operators. In contrast, snorkelling off of Salang on the western side of Tioman, we noted a pattern of increased coral decimation with proximity to land. Snorkelling enabled more of a landscape view of the reefs, and our destinations were more self-determined than driven by the tourist industry/

Similar to what has happened in peninsular Malaysia, Sabah, one of two states in Malaysian Borneo, has seen its primary rain forests substituted by oil palm plantations. We dove in Abdul Rahman Park off of northern Sabah which is less than three kilometers from Kota Kinabalu, the capital. As we expected, the water was much more turbid than it was in Tioman, probably due to frequent boat traffic and proximity to land. However, only three dives were made in this area, so our observations could not be generalized to the entire island group. Local marine researchers from World Wildlife Fund informed us of a group of islands off Kudat (on the northern tip of Sabah) that is soon to become the largest marine park in Southeast Asia, Tun Mustapha Marine Park. Coral reefs in this region are adjacent to areas with differing intensities and duration of forest conversion activities, forming ideal study sites.

During the final leg of our journey, we were able to observe the impacts of land conversion on the Kinabatangan River and its tributaries. The corridor of forest remaining around the river is so small, just a few kilometers on either side, that wildlife has been completely hemmed in along the riverbanks. This unfortunate circumstance has created a healthy tourism industry instead of an abundance of wildlife, the animals are few in number but densely concentrated. The river is light brown and completely opaque from sedimentation, whereas tributaries were more clear. This signifies that the main stem of the river is moving quickly and is full of fine sediments, with no opportunity to settle. This is not surprising considering the expansive area this river drains.

In general, we achieved our goals of locating potential study sites, assessing the general patterns of land use, and observing the condition of corals along a gradient of forest conversion.