The growing demand for sea cucumbers has prompted traders in Zanzibar to call for regulation of exports of the marine species.
They say trade in the sea cucumber is unregulated on the island, with poachers smuggling it to Asian markets.
In China and Hong Kong, a kilogramme of processed sea cucumbers can go for as much as $300, depending on the species. In Zanzibar, the price ranges between Tsh20,000 ($9) and Tsh100,000 ($44.5), depending on the type and size.
Fishermen told The EastAfrican that the sea cucumbers are processed and exported either by sea or air to China, Hong Kong and Dubai, where the demand is high.
"The sea cucumber is our bread and butter and we depend on it for our livelihood," said Amour Ali, a Zanzibar trader, who wants permits to be issued to dealers who must also operate only in season.
Mr Ali said exporting sea cucumbers to Asia via Ethiopian Airlines costs $1.20 per kilogramme.
To process the sea cucumbers, farmers boil them in hot water sprinkled with salt, then dry them on the shore. After thorough drying, one kilo of sea cucumbers shrinks to about 200g. The dried product is considered a luxury food item in Asian seafood markets.
The delicacy not only generates revenue, but also contributes to food security among fishing communities. It is believed to be of high nutritional and medicinal value. It is used in traditional Chinese medicine to treat health problems such as fatigue, impotence and joint pains.
Sea cucumber species in Zanzibar include Myeupe, Tairi, Spinyo baba, Barangu, Nanasi, Kijini, Dole, Barangu mwamba, Sankude, Tambi and Mbura.
The harvest period lasts between six and eight months. There are more than 1,000 species worldwide, according to National Geographic.
The major challenges the fishermen and traders face are resources management, health and safety.
The potential financial rewards in overseas markets are also causing domestic fishermen to take more risks as sea cucumber stocks deplete, and diving farther from shore.