Conserve and sustainably use the oceans, seas and marine resources for sustainable development

The ocean is critical for sustainable development, yet growing efforts to strengthen ocean governance are met with persistent detrimental pressures on marine ecosystems. With increasing absorption of CO2, acidification and warming of the ocean increases; and key marine biodiversity areas remain without full protection. Declining sustainability in fisheries and limited investment in marine research highlight ongoing structural challenges. However, advances in monitoring, management, and international cooperation, including the entry into force of the BBNJ Agreement in January 2026, are improving understanding of ocean state and coordination of efforts aimed at reducing pressures. Ensuring the sustainable use and protection of ocean resources will require investing in sustainable ocean economies, scaling-up effective area-based conservation and integrated coastal zone management, greater protection of the oceans and coastal communities and enhanced investments in science and innovation. 

Target 14.3: As the global average ocean surface pH declines, as a result of rising CO2 emissions and absorption by the ocean, acidification increases. The expansion of monitoring stations (from 178 in 2021 to 906 in 2026) highlights a growing capacity of countries to observe ocean pH. Despite this increase in observations, monitoring remains patchy, hindering the development of strategies for mitigation and adaptation at relevant scales. 

Target 14.4: Fishery resources remain under significant pressure from overfishing and other human-induced impacts; the latest data (2021) show 35.5% of stocks are unsustainable. Although a 2% decline has been estimated over the last six years, the trend appears to have stabilized. 

Target 14.7: Sustainable fisheries as a proportion of GDP declined for the third consecutive period in 2023, from 0.087% to 0.081%, although the value added of fisheries and aquaculture continued to increase, reaching $175 billion in 2023. 

Target 14.a: The median national research budget allocated to marine technology has remained less than 1% across those countries reporting for the period 2013 to 2024. This small allocation contrasts with the growing ocean economy, which now accounts for 3-4% of gross value added to the world’s economy.

Target 14.c: On 17 January 2026, the BBNJ Agreement entered into force, constituting a major milestone for the ocean and multilateralism. The treaty strengthens the legal framework for conserving and sustainably using marine biodiversity in the two-thirds of the ocean that lie beyond national jurisdiction.

The Advance Unedited Version of the 2026 Extended Report on SDG 14 can be found here: https://hlpf.un.org/sites/default/files/2026-06/SG%20Progress%20Report%202026_1.pdf 

The ocean economy supports millions globally but faces intensifying threats from overfishing, pollution and climate change. Despite a decade of conservation efforts, rising CO₂ emissions continue to drive ocean acidification and damage marine ecosystems. Strengthened enforcement has not sufficiently curbed overfishing and illegal practices that deplete fish stocks. Small-scale fisheries have gained support but require additional protection. Safeguarding oceans for future generations demands urgent scaling up of investment in sustainable fishing practices, comprehensive marine conservation and enhanced international cooperation. The United Nations Conferences to Support the Implementation of Sustainable Development Goal 14: Conserve and sustainably use the oceans, seas and marine resources for sustainable development have galvanized global action to protect the ocean, in line with Goal 14.

Target 14.2 - In 2024, 126 countries and territories were engaged in marine spatial planning initiatives, a tool for implementing ecosystem-based approaches to managing marine areas – up 20 per cent from 2023. However, only 45 have formally approved marine spatial plans. 

Target 14.3  - Ocean acidification is worsening as global average surface pH declines, driven by rising CO2 emissions. Continued acidification threatens marine life and climate stability. The expansion of monitoring stations (from 178 in 2021 to 765 in 2025) underscores the need to expand high-frequency and long-term tracking to develop effective mitigation and adaptation strategies. 

Target 14.4  - In 2021, 37.7 per cent of global fishery stocks were estimated to be overfished, up from 35.4 per cent in 2019. While the pace of decline had previously shown signs of slowing, the latest data confirm a continued deterioration. 

Target 14.6 -  Illegal, unreported and unregulated fishing continues to threaten the sustainability of global fisheries. As at January 2025, 78 Parties (65 per cent of coastal States) had joined the Agreement on Port State Measures to Prevent, Deter and Eliminate Illegal, Unreported and Unregulated Fishing, the first binding international instrument developed to combat illegal, unreported and unregulated fishing. Globally, countries’ average degree of implementation has remained steady, with a score of 4 out of 5, from 3 out of 5 in 2018.  

Target 14.b - In 2024, the Voluntary Guidelines for Securing Sustainable Small-Scale Fisheries in the Context of Food Security and Poverty Eradication marked their tenth anniversary, with growing adoption worldwide. However, the global average score, which tracks the implementation of instruments that recognize and protect access rights for small-scale fisheries, dropped from 5 (very high implementation) in 2022 to 4 (high implementation) in 2024, based on reports from 112 countries. However, the overall trend since 2018 has been positive, and more countries have been reporting since 2020.

For more information, please visit: https://unstats.un.org/sdgs/report/2025/

More details on SDG 14 in 2025: https://unstats.un.org/sdgs/report/2025/Goal-14/

The 2025 Extended Report on SDG 14 can be found here: https://unstats.un.org/sdgs/report/2025/extended-report/Extended-Report-2025_Goal-14.pdf

Oceans cover over 70% of the Earth’s surface and play a crucial role in providing food and livelihoods for more than 3 billion people as well as combating the effects of climate change. Yet, alarming trends from declining fish stocks, marine pollution, ocean acidification and habitat destruction threaten marine ecosystems and the livelihoods of coastal communities worldwide. Urgent action is needed to address these challenges and ensure the long-term health and sustainability of the ocean through sustainable fishing practices, marine conservation efforts, pollution reduction and global cooperation to safeguard marine life and ecosystems for future generations.

Target 14.3: Ocean acidification is increasing and will continue to do so if carbon dioxide emissions do not stop rising. An increasing number of countries and stations (from 178 stations in 2021 to 638 in 2024) highlights 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.

Target 14.6: Illegal, unreported and unregulated (IUU) fishing threatens the social, economic and environmental sustainability of global fisheries, hindering countries’ abilities to manage their fisheries effectively. The first binding international agreement to specifically target IUU fishing, the Agreement of Port State Measures, now has 102 States covered under the Agreement (from 25 in 2016), covering 63% of the world’s coastal States. States have made good overall progress with close to 75% scoring highly in their degree of implementation of relevant international instruments in 2022 compared to 70% in 2018.

For more information, please visit: https://unstats.un.org/sdgs/report/2024/

More details on SDG 14 in 2024: https://unstats.un.org/sdgs/report/2024/Goal-14/

The 2024 Extended Report on SDG 14 can be found here: https://unstats.un.org/sdgs/report/2024/extended-report/Extended-Report_Goal-14.pdf

Destructive trends in ocean health have not abated. The ocean, the world’s largest ecosystem, continues to be endangered by rising acidification, eutrophication, declining fish stocks and mounting plastic pollution. While there has been some progress in expanding marine protected areas and combatting illegal, unreported and unregulated fishing over the years, more concerted efforts and acceleration are urgently needed. Urgent and coordinated global action is needed to continue to advance towards SDG14.

• Target 14.1: The global trend of elevated coastal eutrophication continued in 2022 above the 2000-2004 baseline conditions, though different in magnitude from recent years. The highest rates are in the Arabian Sea.
• Target 14.3: Ocean acidification is increasing and will continue to do so if CO2 emissions do not stop rising, threatening marine ecosystems and the services they provide. Today, the ocean's average pH is 8.1. This means that the ocean today is about 30% more acidic than in pre-industrial times.
• Target 14.4: Fishery resources continue to be threatened by overfishing, pollution, poor management and other factors, including illegal fishing. More than a third (35.4%) of global stocks were overfished in 2019, an increase of 1.2% since 2017. Despite ongoing deterioration, the rate of decline has decelerated in recent years. However, the trend continues to deteriorate from the 2020 target to restore fish stocks to biologically sustainable levels.
• Target 14.6: By the end of 2022, the Agreement on Port State Measures, targeting illegal, unreported and unregulated (IUU) fishing, reached 74 Parties, (including the European Union) or effectively 100 States. In the 2018-2022 period, there has been some progress at the global level in implementing instruments to combat IUU fishing. The new WTO Agreement on Fisheries Subsidies, adopted in June 2022, marks a major step forward towards ocean sustainability.
• Target 14.b: Globally, the degree of application of frameworks that recognize and protect access rights for small-scale fisheries in 2022 was at the highest level based on available data, reaching a maximum score of 5 out of 5. However, this score conceals a reduced number of countries that contributed to the reporting.
• Target 14.a: Even though the ocean covers more than 70% of the surface of our planet and contributes to 2.5% of the world gross value added, on average, between 2013 to 2021, only 1.1% of national research budgets were allocated for ocean science.

For more information, please visit: https://unstats.un.org/sdgs/report/2023/

More details on SDG 14 in 2023: https://unstats.un.org/sdgs/report/2023/Goal-14/

The 2023 Extended Report on SDG 14 can be found here: https://unstats.un.org/sdgs/report/2023/extended-report/Extended-Report_Goal-14.pdf

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.

Source: Progress Towards Sustainable Development Goals- Report of the Secretary-General 

For more information, please, check: https://unstats.un.org/sdgs/report/2022/

More details on SDG 14 in 2022: https://unstats.un.org/sdgs/report/2022/Goal-14/

The 2022 Extended Report on SDG 14 can be found here: https://unstats.un.org/sdgs/report/2022/extended-report/Extended-Report_Goal-14.pdf

More than 3 billion people rely on the oceans for their livelihoods, and more than 80 per cent of world merchandise trade by volume is carried by sea. The oceans, seas and marine resources are under constant threat from pollution, warming and acidification that are disrupting marine ecosystems and the communities they support. These changes have long-term repercussions that require the world to urgently scale up the protection of marine environments, investment in ocean science, support for small-scale fishery communities, and the sustainable management of the oceans.

While efforts to reduce nutrient inputs into coastal zones are showing success in some regions, algal blooms indicate that coastal eutrophication continues to be a challenge. Globally, anomalies of chlorophyll-a (the pigment responsible for photosynthesis in all plants and algae) in national exclusive economic zones decreased by 20 per cent from 2018 to 2020.

Ocean acidification is caused by the absorption of atmospheric carbon dioxide by the ocean, resulting in a decreasing pH and threatening marine organisms and ocean-based services. A limited set of long-term observation sites in the open ocean have observed a continuous decline in pH over the past 20 to 30 years.

Mean protected area coverage of marine key biodiversity areas increased globally from 28 per cent in 2000 to 44 per cent in 2020. However, there is considerable geographical variation in this progress, with coverage still less than one quarter of key biodiversity areas in Oceania (excluding Australia and New Zealand).

Improved regulation, together with effective monitoring and surveillance, has proved successful in restoring overfished stocks to biologically sustainable levels. However, the adoption of such measures has generally been slow, in many developing countries in particular. In 13 countries and territories that have active assessment and management systems in place, the proportion of fish stocks within biologically sustainable levels is higher than the world average of 65.8 per cent, according to data collected in 2019.

Between 2018 and 2020, the average degree of implementation of international instruments to combat illegal, unreported and unregulated fishing improved around the world, with the global score measuring the implementation of the five principal instruments rising from 3 to 4 out of 5. Almost 75 per cent of States scored highly in their degree of implementation in 2020, compared to 70 per cent percent of States in 2018.

Between 2018 and 2020, the world made progress in implementing regulatory and institutional frameworks that recognize and protect access rights for small-scale fisheries, with the global score rising from 3 to 4. At the regional level, Northern Africa and Western Asia made this progress, while the regional score for Central and Southern Asia fell from 3 to 2, highlighting the need for efforts there to be redoubled and demonstrating that there is no room for complacency.

Sustainable fisheries accounted for approximately 0.1 per cent of global GDP in 2017, while contributing more than 0.5 per cent of GDP in certain regions and the least developed countries. The sustainable management of fish stocks remains critical to ensuring that fisheries continue to generate economic growth and support equitable development. The long-term impact of the COVID-19 pandemic on fisheries poses significant challenges that threaten to undermine sustainable stock management and profitability.

On average, only 1.2 per cent of national research budgets was allocated to ocean science between 2013 and 2017, with amounts ranging from 0.02 per cent to 9.5 per cent. This is a small proportion in view of the conservatively estimated $1.5 trillion contribution of the ocean to the global economy in 2010.

Many States have ratified or acceded to the United Nations Convention on the Law of the Sea (168 parties) and its implementing agreements (150 parties for the Agreement relating to the implementation of Part XI of the United Nations Convention on the Law of the Sea and 91 parties for the United Nations Fish Stocks Agreement). A number of States have implemented these instruments through legal, policy and institutional frameworks, but further progress is needed in some developing countries, in particular the least developed countries.

Source: Progress towards the Sustainable Development Goals – E/2021/58

For more information, please, check: https://unstats.un.org/sdgs/report/2021/

More details on SDG 14 in 2021: https://unstats.un.org/sdgs/report/2021/Goal-14/

The 2021 Extended Report on SDG 14 can be found here: https://unstats.un.org/sdgs/report/2021/extended-report/Goal%20(14)_final.pdf

Oceans and fisheries continued to support the global population’s economic, social and environmental needs while suffering unsustainable depletion, environmental deterioration and carbon dioxide saturation and acidification. Current efforts to protect key marine environments and small-scale fishers and invest in ocean science are not yet meeting the urgent need to protect this vast, fragile resource.

The ocean absorbs around 23 per cent of the annual emissions of anthropogenic carbon dioxide to the atmosphere, helping to alleviate the impacts of climate change on the planet, however, resulting in a decreasing pH and acidification of the ocean. A new ocean acidification data portal shows an increase in variability in pH and the acidity of the oceans by 10 to 30 per cent in the period 2015–2019. 

The sustainability of global fishery resources continues to decline, though at a reduced rate, with the proportion of fish stocks within biologically sustainable levels at 65.8 per cent in 2017, down from 90 per cent in 1974 and 0.8 percentage point lower than 2015 levels. 

As at December 2019, more than 24 million km2, or 17 per cent, of waters under national jurisdiction (up to 200 nautical miles from shore) were covered by protected areas, more than doubling in extent since 2010. Much of the coverage is concentrated in Oceania and Latin America and the Caribbean.

As at February 2020, the number of parties to the Agreement on Port State Measures to Prevent, Deter and Eliminate Illegal, Unreported and Unregulated Fishing –  the first binding international agreement that specifically targets illegal, unreported and unregulated fishing – increased to 66 (including the European Union) from 58 in the previous year, and nearly 70 per cent of countries reported scoring high on the implementation thereof.

The contribution of sustainable marine capture fisheries remained stable at the global level, with regional variation, representing the largest contribution to the GDP in Pacific small island developing States and least developed countries, averaging 1.55 and 1.15 per cent, respectively, in 2011 to 2017. 

Source: Progress towards the Sustainable Development Goals, Report of the Secretary-General, https://undocs.org/en/E/2020/57

For more information, please visit: https://unstats.un.org/sdgs/report/2020/

More details on SDG 14 in 2020: https://unstats.un.org/sdgs/report/2020/Goal-14/

The expansion of protected areas for marine biodiversity and existing policies and treaties that encourage responsible use of ocean resources are still insufficient to combat the adverse effects of overfishing, growing ocean acidification due to climate change and worsening coastal eutrophication. As billions of people depend on oceans for their livelihood and food source and on the transboundary nature of oceans, increased efforts and interventions are needed to conserve and sustainably use ocean resources at all levels.

• Ocean acidification is caused by the uptake of atmospheric CO2 by the ocean, which changes the chemical composition of the seawater. Long-term observations of ocean acidification over the past 30 years have shown an average increase of acidity of 26 per cent since pre-industrial times, and at this rate, an increase of 100 to 150 per cent is predicted by the end of the century, with serious consequences for marine life.
• To achieve sustainable development of fisheries, fish stocks must be maintained at a biologically sustainable level. Analyses reveal that the fraction of world marine fish stocks that are within biologically sustainable levels declined from 90 per cent in 1974 to 66.9 per cent in 2015.
• As of December 2018, over 24 million km2 (17.2 per cent) of waters under national jurisdiction (0–200 nautical miles from a national border) were covered by protected areas, a significant increase from 12 per cent in 2015 and more than double the extent covered in 2010. The global mean percentage of each marine key biodiversity area covered by protected areas increased from 31.2 per cent in 2000 to 44.7 per cent in 2015 and to 45.7 per cent in 2018.
• Illegal, unreported and unregulated fishing remains one of the greatest threats to sustainable fisheries, the livelihoods of those who depend upon them and marine ecosystems. A framework of international instruments has been developed that addresses different aspects of fisheries management. Most countries have taken measures to combat such fishing and have adopted an increasing number of fisheries management instruments in the past decade. For example, the Agreement on Port State Measures to Prevent, Deter and Eliminate Illegal, Unreported and Unregulated Fishing, the first international binding agreement to combat such fishing, entered into force in June 2016. The number of parties to the Agreement has rapidly increased and stood at 58 as of February 2019.
• Small-scale fisheries are present in almost all countries, accounting for more than half of total production on average, in terms of both quantity and value. To promote small-scale fishers’ access to productive resources, services and markets, most countries have developed targeted regulatory and institutional frameworks. However, more than 20 per cent of countries have a low to medium level of implementation of such frameworks, particularly in Oceania and Central and South Asia.

Source: Report of the Secretary-General, Special edition: progress towards the Sustainable Development Goals

For more information, please visit: https://unstats.un.org/sdgs/report/2019/

More details on SDG 14 in 2019: https://unstats.un.org/sdgs/report/2019/Goal-14/

Advancing the sustainable use and conservation of the oceans continues to require effective strategies and management to combat the adverse effects of overfishing, growing ocean acidification and worsening coastal eutrophication. The expansion of protected areas for marine biodiversity, intensification of research capacity and increases in ocean science funding remain critically important to preserve marine resources.

• The global share of marine fish stocks that are within biologically sustainable levels declined from 90 per cent in 1974 to 69 per cent in 2013.
• Studies at open ocean and coastal sites around the world show that current levels of marine acidity have increased by about 26 per cent on average since the start of the Industrial Revolution. Moreover, marine life is being exposed to conditions outside previously experienced natural variability.
• Global trends point to continued deterioration of coastal waters due to pollution and eutrophication. Without concerted efforts, coastal eutrophication is expected to increase in 20 per cent of large marine ecosystems by 2050.
• As of January 2018, 16 per cent (or over 22 million square kilometres) of marine waters under national jurisdiction—that is, 0 to 200 nautical miles from shore—were covered by protected areas. This is more than double the 2010 coverage level. The mean coverage of marine key biodiversity areas (KBAs) that are protected has also increased—from 30 per cent in 2000 to 44 per cent in 2018.

Source: Report of the Secretary-General, The Sustainable Development Goals Report 2018

For more information, please visit: https://unstats.un.org/sdgs/report/2018/

Goal 14. Conserve and sustainably use the oceans, seas and marine resources for sustainable development 18. The increasingly adverse impacts of climate change (including ocean acidification), overfishing and marine pollution are jeopardizing recent gains in protecting portions of the world’s oceans.

• Global trends point to continued deterioration of coastal waters owing to pollution and eutrophication (excessive nutrients in water, frequently a result of run-off from land, which causes dense plant growth and the death of animal life from lack of oxygen). Of the 63 large marine ecosystems evaluated under the Transboundary Waters Assessment Programme, 16 per cent of the ecosystems are in the “high” or “highest” risk categories for coastal eutrophication. They are located mainly in Western Europe, Southern and Eastern Asia, and the Gulf of Mexico.
• Ocean acidification is closely linked to shifts in the carbonate chemistry of the waters, which can lead to a significant weakening of the shells and skeletons of many marine species (such as reef-building corals and shelled molluscs).
• Studies of marine acidity at open ocean and coastal sites around the world have indicated that current levels are often outside preindustrial bounds.
• Overfishing reduces food production, impairs the functioning of ecosystems and reduces biodiversity. The proportion of world marine fish stocks within biologically sustainable levels has declined from 90 per cent in 1974 to 68.6 per cent in 2013. However, the trend has slowed and appears to have stabilized from 2008 to 2013.
• Small-scale fisheries face numerous challenges. In response, about 70 per cent of the respondents to a survey representing 92 countries and the European Union have introduced or developed regulations, policies, laws, plans or strategies specifically targeting small-scale fisheries.
• When effectively managed and well resourced, marine protected areas are important mechanisms for safeguarding ocean life. In 2017, protected areas cover 13.2 per cent of the marine environment under national jurisdiction (up to 200 nautical miles from shore), 0.25 per cent of the marine environment beyond national jurisdiction and 5.3 per cent of the total global ocean area.

Source: Report of the Secretary-General, "Progress towards the Sustainable Development Goals", E/2017/66

For more information, please visit: https://unstats.un.org/sdgs/report/2017/

• Oceans, along with coastal and marine resources, play an essential role in human well-being and social and economic development worldwide. They are particularly crucial for people living in coastal communities, who represented 37 per cent of the global population in 2010. Oceans provide livelihoods and tourism benefits, as well as subsistence and income. They also help regulate the global ecosystem by absorbing heat and carbon dioxide from the atmosphere and protecting coastal areas from flooding and erosion. In fact, coastal and marine resources contribute an estimated $28 trillion to the global economy each year through ecosystem services. However, those resources are extremely vulnerable to environmental degradation, overfishing, climate change and pollution. The sustainable use and preservation of marine and coastal ecosystems and their biological diversity is essential to achieving the 2030 Agenda, in particular for small island developing States.
• Pollution of both land and seas is a threat in many coastal regions. In addition, since river basins, marine ecosystems and the atmosphere are all part of hydrological systems, the effects of such pollution are often felt far from their source. In many coastal communities, pollution and eutrophication, which is the presence of excessive nutrients in water, frequently owing to runoff from the land, causing dense plant growth and the death of animal life, are driving detrimental changes. The five large marine ecosystems most at risk from coastal eutrophication, according to a global comparative assessment undertaken in 2016 as part of the Transboundary Water Assessment Programme, are the Bay of Bengal, the East China Sea, the Gulf of Mexico, the North Brazil Shelf and the South China Sea.
• Since the beginning of the industrial revolution, the ocean has absorbed about one third of the carbon dioxide released by human activities, thereby mitigating the full impact of climate change. However, this comes at a steep ecological price, as dissolved carbon dioxide in seawater lowers the pH level of oceans, thereby increasing acidity and changing the biogeochemical carbonate balance. Concerns about ocean acidification, first expressed in the early 1980s, have now been confirmed, and the extent of its impact on marine ecosystems is being investigated.
• Fisheries contribute significantly to global food security, livelihoods and the economy. However, if not sustainably managed, fishing can damage fish habitats. Ultimately, overfishing impairs the functioning of ecosystems and reduces biodiversity, with negative repercussions for sustainable social and economic development. In order to achieve a healthy balance, fish stocks must be maintained within biologically sustainable limits, at or above the abundance level that can produce maximum sustainable yields. Based on an analysis of assessed stocks, the percentage of world marine fish stocks within biologically sustainable levels declined from 90 per cent in 1974 to 69 per cent in 2013. Fortunately, the downward trend has slowed and appears to have stabilized since 2008.
• Biodiverse marine sites require safeguarding to ensure sustainable long-term use of their precious natural resources. Globally, in 2014, 8.4 per cent of the marine environment under national jurisdiction (up to 200 nautical miles from shore) and 0.25 per cent of the marine environment beyond national jurisdiction were under protection. From 2000 to 2016, the share of marine sites around the world that are designated as key biodiversity areas and are completely covered by protected areas increased from 15 per cent to 19 per cent.

Source: Report of the Secretary-General, "Progress towards the Sustainable Development Goals", E/2016/75

For more information, please visit: https://unstats.un.org/sdgs/report/2016/