Let's hear more on deep ocean aquaculture

July 16, 2025

Julian Cribb cites a possible part-solution to the world’s food crisis, namely, “deep ocean aquaculture”. Unlike coastal fish farms, including the contentious Tasmanian salmon farms, aquaculture in the deep ocean allows currents to remove all wastes, which in coastal waters have destroyed wild ecosystems and threatened species such as the Maugean skate in Macquarie Harbour.

Deep ocean aquaculture would allow us to eat salmon without the overwhelming guilt that accompanies eating it now. It would help maintain global protein supplies which are at risk because land-based production of meat is exacerbating climate change through land-clearing and emissions from ruminants.

We rightly say we have to eat lower down the food chain to help mitigate global warming but, for many people, that may entail a loss of vital nutrients that are contained in meat and dairy products. Nearly half the Indian women, for instance, who eat a vegetarian diet are already anaemic. You have to eat an awful lot of spinach to get the necessary iron if you are not eating meat or certain fish. Oysters, mussels, cuttlefish, and octopus are particularly high in iron and could be farmed as part of deep ocean aquaculture.