In the 17th century, China developed a demand for trepang or sea slug (a kind of holothurian) for cooking. The animals live in shallow tropical and sub-tropical waters and were collected first from the South China Sea. As those fields were fished out, however, trepang collectors turned to other regions.
By late in the 18th century, fishermen from Makasar had begun to travel regularly to the northern coast of Australia, using compass and dead reckoning to cross the Timor Sea. The coasts of Arnhem Land (Marege') and the Kimberley (Kayu Jawa) were the most important collecting regions and the trepang was smoked and dried on the spot in preparation for the return voyage and on-shipment to China. It has been estimated that perhaps six hundred tons of trepang were collected each season. The visits continued until the early years of the twentieth century and had a significant cultural influence on Aborigines in northern Australia. Words from Makasar entered Aboriginal languages, Indonesian plant species became part of the local diet, and goods from Makasar entered Aboriginal trading networks. A few Aborigines travelled back with boats to Makasar, where they settled.
Macknight, C.C., The voyage to Marege': Macassan trepangers in northern Australia. Melbourne: Melbourne University Press, 1976.