Coordinated by Emeritus Professor John Bolton, Department of Biological Sciences, University of Cape Town 

Wednesday 24–Friday 26 January 9.15 am COURSE FEES R330; Staff and students R165      T

More than 50% of the seafood consumed globally is produced in aquaculture, which is the farming of aquatic organisms, such as fish, abalone, sea urchins or algae in controlled environments. However, as with any farming, the environmental impact of these practices should be considered to ensure sustainable seafood production. Integrated multi-trophic aquaculture (IMTA), where the waste from one farmed species is recaptured for use by another, represents a sustainable production method that can reduce the environmental impacts of aquaculture, increase the number of species that are farmed, and increase production. For example, the solid waste excreted by abalone can be used as a food source for sea cucumbers, while the dissolved ammonia in the water can be used as a fertiliser for seaweeds. The seaweeds also act as bio-filters so that water can be re-used, and the seaweed can be used as a feed. These lectures will explore marine aquaculture and the implementation of IMTA in South Africa, and globally in the context of the EU-funded ASTRAL project.


Lecture titles

  1. Overview of integrated aquaculture Dr Marissa Brink-Hull
  2. Integrated aquaculture and the importance of seaweeds  Emeritus Professor John Bolton
  3. Sustainable strategies for improving health of intensive aquaculture systems  Dr Brett Macey

Recommended reading

All Atlantic sustainable, profitable and resilient aquaculture (ASTRAL) project. Available at:

Swingler, H. and Bolton J.J. 2018. Aquaculture key to food security and nutrition? Available at:

van Beijnen, J. and Yan, G. The multi-trophic revolution: a deep dive with IMTA guru Thierry Chopin. The Fish Site, 16 April 2021. guru-thierry-chopin-polyculture-salmon-mussels-seaweed#:~:text=Chopin%20describes%20IMTA%20 as%3A%20%E2%80%9CThe,other%20crops%2C%20and%20to%20take

ASTRAL IMTA lab South Africa YouTube video. Available at: