Seaweed Aquaculture in Africa: From East African Farms to Southern Africa's Kelp Forests

John Bolton is Emeritus Professor at the University of Cape Town with over 40 years of research on seaweeds along Africa's coastlines, and has been very involved in practically all forms of seaweed aquaculture in Africa and further afield. Sarah Halse works in research and production at a South African abalone farm, where she manages large-scale Ulva production and has developed hands-on expertise in seaweed-based feeding systems for abalone.In this episode, we take a geographic tour of seaweed aquaculture across Africa. We start in East Africa with Tanzania's Eucheuma industry, the continent's one real commercial success story, and explore why it took hold there and not elsewhere. We then move to the Western Indian Ocean islands before heading south to the cold-water coasts of South Africa and Namibia, where we dig into land-based Ulva production, the role of Gracilaria as an abalone weaning feed, sustainable kelp harvesting, and the ambitious offshore Kelp Blue project in Lüderitz. We also get into the open question of non-indigenous species, the challenges of scaling seaweed markets in the West, and why years of tacit knowledge often matter more than technology.This episode is part of the LIMAQUA Focus Series, produced under the LIMAQUA Programme, a South African-French joint research initiative on nutrition-sensitive marine aquaculture.