The world’s oceans and seas continue to struggle against increased acidification, eutrophication, and plastic pollution, which are endangering the planet’s largest ecosystem and the billions of livelihoods depending on them. The pandemic has not eased that burden, as an estimated 25,000 tons of plastic waste has steadily entered the global ocean owing to an increase in single-use plastic primarily from medical waste. Owing to the initial lockdowns arising from the COVID-19 pandemic, most countries experienced a 40–80 per cent decline in fish production, with small-scale fisher communities hardest hit. The pandemic also led to a dramatic reduction in tourism, causing substantial income losses for coastal and island communities.

The satellite-derived eutrophication indicator shows an increasing trend from 2016 to the present. While the COVID-19 pandemic may have caused some reduction in coastal pollution in certain areas owing to reduced tourism and activity, the pandemic does not appear to have globally reduced eutrophication. In fact, there was an increase of over 23 per cent in the peak values of the indicator for the 2020 and 2021 calendar year average, compared with the mean value for previous years.

Ocean acidification is the consequence of uptake of atmospheric CO2 by the ocean, resulting in a decreasing pH level and increasing acidification of the ocean, thereby negatively affecting marine organisms and ocean services. Data collected from 308 stations of 35 countries in 2022 highlight the growing capacity of countries to observe the continued decline of ocean pH in the global ocean as well as the strong regional differences in the pace of change.

Between 2018 and 2022, the average degree of implementation of international instruments to combat illegal, unreported and unregulated fishing as measured by the indicator has improved across the world. In this period, the global aggregated indicator has risen from 3 to 4 (out of a maximum score of 5). Countries have thus made good overall progress with close to 75 per cent scoring high in their degree of implementation of relevant international instruments in 2022 compared with 70 per cent in 2018.

In the International Year of Artisanal Fisheries and Aquaculture 2022, the level of adoption of regulatory frameworks supporting small-scale fisheries and promoting participatory decision-making has improved worldwide. The average global score has risen to 5 out of 5 in 2022, up from 4 out of 5 in 2020 and 3 out of 5 in 2018.

Overall, many States have ratified or acceded to the 1982 United Nations Convention on the Law of the Sea (168 parties) and its implementing agreements (Agreement relating to the Implementation of Part XI of the United Nations Convention on the Law of the Sea of 10 December 1982: 151 parties; and Agreement for the Implementation of the Provisions of the United Nations Convention on the Law of the Sea of 10 December 1982 relating to the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks: 91 parties). While many States have implemented those instruments through legal, policy and institutional frameworks, this remains an area for further progress in several developing countries, in particular least developed countries.