I REFER to the letter "Too many chalets on Sipadan Island" by Z.A. Yacob (NST, May 25), who contended that the world-renowned marine ecosystem in Sipadan Island could be spared from further deterioration if divers were to be accommodated on other nearby islands.

I have gone scuba diving a number of times not only in Sipadan Island but also off two other nearby islands and have just recently returned from one such expedition.

From my observation, though overcrowding in Sipadan Island is a perennial problem due to its fame, accommodating divers on other nearby islands will not help to conserve the marine ecosystem of Sipadan Island.

Sipadan Island is a mere tip of a steep underwater mountain with an area of only about 16ha. It has very limited beaches, and its interior is uninhabitable as it is covered with dense and untouched tropical forest.

Currently there are at least six diving operators on the islands and their facilities are all clustered near the famous and legendary Sipadan Drop-Off. With only 10 dive sites along the perimeter of the island, it is to be expected that the underwater beauty of its walls and seabed will deteriorate with time due to continuous visits by divers.

In the vicinity of Sipadan Island, there are two other islands, namely Mabul and Kapalai. Mabul Island is slightly bigger than Sipadan Island while Kapalai is only a sandbank which becomes visible only during low tide, Mabul is only about 15 minutes away from Sipadan by speedboat, but is closer to the mainland and Semporna.

On Mabul Island there are two resorts which are more up-market than those rustic chalets found on Sipadan Island. Besides these two resorts there is a recent addition which is by no means a conventional one. It is an old oil rig just off the coast of Mabul Island, which has been converted into a 40-room diving centre.

On Kapalal Island, there are some new bungalows built on piles and jutting out on to the reef. But at the time of my visit during the third week of May, they were unoccupied.

Though there are more than half a dozen sites in Mabul and Kapalai islands, visitors staying in Mabul also dive around Sipadan Island.

Besides visitors, Mabul Island is also inhabited by a colony of fishermen and their families who migrated mainly from the Philippines. The migrants built their ramshackle houses along the beach of the island. A new primary school including a teachers' quarters has also been constructed.

Therefore this island is already overcrowded. The islanders, depending on waters around the islands for their livelihood, have almost completely destroyed the reefs in Mabul and Kapalai through the practice of dynamite fishing.

They also use nets to fish in surrounding waters and this would undoubtedly contribute to the depletion of underwater fauna around the islands of Sipadan, Mabul and Kapalal.

Therefore to preserve or minimise the deterioration of marine ecosystem in Sipadan and the surrounding islands, the Marine Department and other relevant authorities should formulate and implement adequate policies to effectively control the number of visitors to these islands.

As a first step, the authorities should not permit the construction of new chalets and establishment of new diving centres on these islands. Furthermore the authorities should consider the relocation of existing fishermen and their families to the mainland.

Lastly, waters around the islands should be established as a marine park to prohibit all forms of fishing.