Small-scale octopus fisheries can provide sustainable source of vital nutrients for tropical coastal communities

Research led by Cambridge scientists, and published today in Nature Food, shows that tropical small-scale octopus fisheries offer a sustainable source of food and income to communities that face food insecurity, where the prevalence of undernourishment can exceed 40% and stunting in children under five commonly exceeds 30%.

The high micronutrient density of octopus -- including vitamin B12, copper, iron and selenium -- means that human populations only need to eat a small quantity to supplement a diet primarily comprising staple plant crops. Just a small amount of production in a tropical small-scale octopus fishery can deliver the micronutrient needs to a relatively large number of people.

The fast growth and adaptability of octopuses to environmental change can also facilitate sustainable production, and catch methods in the fisheries -- primarily consisting of hand techniques, small-scale lines, pots and traps -- are less environmentally harmful than those of large industrial fishing.

Dr David Willer, lead author, from the Department of Zoology at the University of Cambridge and a Fellow at Murray Edwards College, said: "Worldwide, nearly half of people's calories come from just three crops -- rice, wheat, and maize -- which are high energy, but relatively low in key nutrients. Just a small serving of something very, very micronutrient rich, like octopus, can fill critical nutritional gaps. And, of course, if you get better nutrition as a child you're much more physically and mentally prepared for later life, which can lead to better jobs, better employment and better social development.

"These small fisheries also provide an income and a livelihood, often to women whose economic status is enhanced as a result. Small-scale octopus fisheries revolve around local communities and potentially that gives them a greater resilience against market pressures and other disruptions to global food supply and trade."

Small-scale fisheries, across all sectors, currently provide more than two-thirds of the fish and seafood destined for human consumption worldwide, and employ over 90% of fishers involved in capture fisheries. 47% of the workforce employed in these fisheries are women.

Based on a global review of data from global seafood databases and published literature, the researchers found that in many cases tropical small-scale octopus fisheries are operating using relatively low impact techniques, and when combined with local and national management approaches can provide a more sustainable source of seafood. Successful approaches include periodic fishery closures, size restrictions, and licences. The need for knowledge transfer of fishing gears is also crucial so that the message on fish sustainability and securing the food supply and economic stability is spread widely.