A new study by an international team of researchers has revealed the huge role Indian Ocean fisheries play in feeding the world and supporting nutritional security.
The study was published in the journal Fish and Fisheries and carried out by researchers from The University of Western Australia, the Harvard TH Chan School of Public Health and the University of British Columbia.
Researchers found that seafood caught in the Indian Ocean provided 12 per cent of all global wild-caught seafood, nearly 30 per cent of all calcium from seafood worldwide, almost 20 per cent of vitamin A, 15 per cent of iron, and 13 per cent of vitamin B12.
Lead author and UWA PhD candidate Vania Andreoli, from UWA's School of Biological Sciences and Oceans Institute, said the nutrients were essential for the health of more than 800 million people living in the Indian Ocean region.
"Our study highlights just how critical the Indian Ocean is – not just for food, but for the nutrients that keep millions healthy," Ms Andreoli said.
The study also uncovered that some small fish, such as anchovies, play an outsized role in nutrition. Although anchovies make up only about 2.5 per of the total catch by weight, they deliver more than 20 per cent of the Indian Ocean's micronutrient supply.
Anchovies, which are rich in healthy omega-3 fatty acids, are also affordable and more resilient to overfishing and climate change than larger, more expensive fish such as tuna.
Jessica Zamborain-Mason, Postdoctoral Research Fellow at Harvard TH Chan School of Public Health said anchovies, herring, mackerel and sardines were all excellent sources of protein, micronutrients such as iron, zinc, vitamin B12 and calcium, as well as heart-healthy omega-3 fatty acids.
"In contrast, species like tuna and squid are less nutrient-dense, more costly, and more vulnerable to environmental pressures," Ms Zamborain-Mason said.
"Tuna and squid are also the main targets for large foreign fishing fleets that operate in the Indian Ocean but are from outside the region."
The fishing fleets capture only about two per cent of the Indian Ocean's total micronutrient supply, although tuna are richer in certain nutrients such as selenium.
Tuna have higher economic value and are more vulnerable to overfishing and climate change. This means that large foreign fishing fleets place additional pressures on already at-risk populations while exporting economic and nutritional benefits out of the region, thereby limiting opportunities for local communities.
Ms Andreoli said managing fisheries wasn't only about the tonnes caught or their market price.
"It's about making sure the right fish reach the people who need them most, while keeping the ocean healthy for generations to come," she said.
The study offers crucial insights for policymakers and conservationists seeking to balance nutrition, economics and sustainability in one of the world's most important oceans.
