[Details from Komilus et al. 2000, unless otherwise credited].

Seaweed culture in Semporna has a long history since its inception in the late 1970s. In 1978, a US-based consulting company was appointed by the Department of Fisheries (DOF) Sabah to carry out Research and Development on the culture of Euchema cottonii in Semporna. Seaweed farming was given priority by DOF Sabah as a supplementary income-generating activity among the fishing community with the establishment of a demonstration farm within the SIP area in 1980. More people have gradually become involved in seaweed farming. For example, the residents of Pulau Selakan began seaweed farming in mid-1994, and since then it has grown and is flourishing as it provides a good income. Many of the Bajau here have switched from fishing to seaweed cultivation.

The main species cultured used to be Euchema cottonii and Euchema spinosum, but farmers have stopped culturing the latter as exporters prefer E. cottonii because it fetches better prices.

2.2.1. Location
Seaweed culture plots are found mostly on the extensive 'reef top platform' to the north of Sebangkat and Selakan, and also at various locations off Pu Bodgaya and Pu Boheydulang. There have been plots off Sibuan and Maiga but these are not currently operating. Komilus et al. (2000) report that Lembaga Kemajuan Ikan Malaysia (LKIM - The Malaysian Fish Development Board), through the Department of Fisheries Sabah is planning to take up seaweed farming at Sebangkat, where it has applied for a Temporary Occupation Licence (TOL) for 200 acres (80 ha).

2.2.2. Culture System
The culture system commonly used within the proposed Park is the long-line method, which is suited to the deeper water conditions of the islands (Komilus et al. 2000). Farmers stretch nylon monofilament long-lines (0.5 mm diameter) across the farming area, commonly around 200 yards (200m) long. One seedling of seaweed is tied to the line at 1-foot (30cm) intervals. A total seedling weight of 100-200g is tied, and the harvesting is every two months, by which time the plant is 1-3 kg in weight. Apart from the seeding and harvest, this culture system requires minimal maintenance. The main jobs are removal of foreign materials, attention to the long-line floats and moorings, removal of any dead or fungal affected plants, and some predator control.

2.2.3. Seaweed production and economic value
The harvested seaweeds are sun-dried after cleaning. In normal weather, it takes 4 days to sun-dry the seaweed to around 35% moisture content. Approximately 9 kg of wet seaweed produces around 1 kg of dry seaweed. Field surveys indicate an average yield of around 10-15 metric tons dry weight/ha. After drying, the seaweeds are sold to local buyers for export.
An average of RM600 to RM1,400 could be obtained from a good harvest, which is equivalent to between RM 300 to RM700 per month (Komilus et al. 2000). According to Baptist et al (1998) a seaweed cultivator can earn from RM600 - 800 per month. To add to their income, these farmers may fish on a part-time basis.

Seaweed culture requires low capital investment and has a fast turnover with good returns. Realising its value, the Department of Fisheries has encouraged seaweed culture around the islands in the proposed Park, and gives some assistance in terms of seedlings, mono-line rope (tie-tie) and floats. Fuel has to be purchased, but most of the costs are non-cash costs in the form of family labour.