Some of Mafia Island and its associated islands are protected by the Mafia Island Marine Park. How would you describe this region?

The park covers more than 700 square kilometres (270 square miles) and encompasses six islands, including the inhabitated islands of Chole, Juani, Jibondo and Bwejuu. There is a buffer zone 800 metres (875 yards) wide that encircles the entire park to mitigate the effects of activities like commercial fishing outside its borders. The protected waters of Mafia Island are high in species and genetic diversity: the shallow waters host, among others, more than 400 fish and 400 sponge species, as well as 200 different algae. The Mafia Island ecosystem also acts as the source of many different larvae that are distributed northwards by the North East African Coastal Current, enriching marine life found many kilometres from the archipelago.

How do you go about interviewing the fishermen at landing sites to survey their catch?

Before I started my research, I visited all the fish landing sites on Mafia Island and introduced myself to village chairmen and to fishing leaders. I then arranged
to meet the local fishermen who specifically target rays. During our meeting, we agreed on how I would be getting samples from them in the future. Some of the local fishermen actually allowed me to board their fishing vessels for night-fishing so that I could get a sense of exactly what happens on the fishing ground.

Have you learnt anything particularly interesting as your project unfolds?

Yes, while interviewing the local fishermen I have been told very interesting stories about ray fish behaviour during the rainy season and when the sea temperature changes. More research now needs to be done to interpret these stories scientifically. And in terms of concerns about the demand for rays in the targeted fishery, it looks like ray liver oil is now becoming a desirable product. People mix it with paint to give it an unpleasant smell that deters the organisms that stick to the hull of fishing vessels and affect their speed, performance and durability.