Zanzibari women grow sea sponges in response to climate change

A team of 13 women, all of whom rely on the ocean for their income, have formed part of a local sponge farming charity

Spotted: Over the past year, locals on the Tanzanian island of Zanzibari have seen a depletion of fish and seaweed stocks. To protect their income, the women on the island have turned to farming natural sea sponges that can withstand climate shocks. 

“I learned to swim and to farm sponges so I could be free and not depend on any man,” Nasir Hassan Haji. one of the 13 women growing and selling the sponges, told Reuters.

Before farming sponges, Haji cultivated seaweed, but global warming has led to increasing ocean temperatures, changing rainfall patterns and ocean salinity, making it difficult to grow seaweed.  Research carried out by State University of Zanzibar showed that over 90 per cent of seaweed farmers on the island were women.  

Six years ago, environmental charity marinecultures.org started teaching women to swim and farm sponges. Swiss Christian and Connie Vaterlaus are the charity’s founders, and over the years, the duo has collected sponge particles from around the island to grow them in the farm’s nurseries.  

Together, the team has grown around 1,500 sponges. In a month of a successful harvest, the farmers can sell 10 to 20 sponges for up to $20 each (about €17.04), Vaterlaus says. 

In addition to the economic benefits, the sponges feed on particles in the water, before filtering the water. The charity trains about four additional women each year and has led to many of them becoming conservationists, said Reuters.  

The charity is in the process of expanding sponge farming into Madagascar and Tunisia, which have environments similar to that of Jambiani. 

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