Marine protected and conserved areas covered 8.44% of global marine and coastal areas in 2024. The same assessment recorded 30.24 million km² in marine protected areas, plus 403,605 km² in marine other effective area-based conservation measures (OECMs). Coverage has expanded substantially, but protection intensity and implementation remain uneven.
Contents
- Global coverage and growth
- Biodiversity priority areas
- Protection intensity and management
- Australia, New Zealand, and Canada
- United States coverage
- Canadian protected-area size examples
Global coverage and growth
The Protected Planet Report 2024 measured a 1.77 million km² increase in marine and coastal protected and conserved coverage between 2020 and 2024. Across the longer 2000–2024 period, coverage increased by 650%. These figures describe change in the area recorded as protected or conserved; they do not by themselves indicate that all sites had the same restrictions or management quality.
The 2024 assessment placed the remaining gap to the 30% coverage target at 21.56 percentage points. Reaching that target would require another 78.26 million km² of marine and coastal area to be established or recognized. The size of that gap shows why percentage coverage and the practical effectiveness of protection need to be read together.
The global database contained 18,692 marine protected areas in August 2024. It also contained 211 marine OECM sites. Marine protected areas accounted for 30.24 million km², while marine OECMs added 403,605 km². OECMs represented 1.12% of marine sites, compared with 2.15% of terrestrial sites.
The geographic distribution of recorded sites was also concentrated in national-jurisdiction waters. The 2024 assessment identified 18,903 marine protected and conserved sites in those waters, covering 27.42 million km². Only 10 marine protected areas were reported in areas beyond national jurisdiction, although those 10 high-seas sites covered 3.22 million km².
Biodiversity priority areas
Area-based coverage is only one way to assess whether protection reaches places important for biodiversity. The Sustainable Development Goals Extended Report 2024 reported that mean marine Key Biodiversity Area coverage rose from 25.8% in 2000 to 46.0% in 2024. This is a 20.2 percentage-point increase across the period.
Regional progress differed. In Oceania excluding Australia and New Zealand, mean marine Key Biodiversity Area coverage increased from 5.8% in 2000 to 22.6% in 2024. Northern America and Europe increased from about 40% to about 60% over the same period. These are regional means, so they do not describe every country or every individual priority area.
The Protected Planet Report 2024 found that 32% of Key Biodiversity Areas had no formal protected or conserved-area coverage in the 2024 assessment. More than two-thirds were partially or fully covered. The mean share of each mapped Key Biodiversity Area within a protected area or OECM was 47.72% in 2024, and OECMs contributed 0.54 percentage points to that mean.
The same source reported an 18.64 percentage-point increase in mean Key Biodiversity Area coverage between 2000 and 2024. Looking beyond mapped priority areas, protected or conserved areas covered 61.65% of the habitat-suitable ranges needed to safeguard 12,904 assessed marine species in 2024. The two measures answer different questions: one describes overlap with Key Biodiversity Areas, while the other describes coverage of suitable ranges for assessed species.
Protection intensity and management
The global percentage classified as protected is not equivalent to the percentage with strong restrictions or active management. In the 2024 Protected Planet Report assessment, 5.7% of the global ocean was in marine protected areas that were implemented and/or actively managed. Only 2.8% was in fully or highly protected marine protected areas.
The August 2024 MPA Guide assessment provided more detail on the 8.4% of ocean area in marine protected areas. It assessed 69% of that area as actively managed and 21% as not yet implemented. Among actively managed marine protected area coverage, 49% was fully or highly protected. At the same time, high-impact extractive or destructive activities occurred in 50% of the assessed marine protected area coverage.
These values describe different dimensions of the same protection system rather than a single ladder. “Actively managed” indicates a management status, while “fully or highly protected” describes the strength of restrictions. The result is that a site can count toward area coverage without being fully protected, and a designated site may not yet be implemented.
Evidence about effectiveness was much less extensive than the mapped coverage itself. Management-effectiveness assessments covered 1.26% of the world’s marine area in the 2024 assessment. Governance assessments had been reported for only 0.001% of the area covered in the marine realm. These percentages indicate limited assessment coverage, not a finding that the remaining areas are ineffective.
Australia, New Zealand, and Canada
National statistics use different boundaries, categories, and reporting dates, so the figures below should not be treated as a perfectly standardized ranking.
| National snapshot | Coverage or area | Measurement period | Source |
|---|---|---|---|
| Australia | 52%; about 4.6 million km² | Latest snapshot after CAPAD 2024 | Achieving 30 by 30 |
| New Zealand marine reserves | 9.5% of territorial sea; 17,178 km² | 1 July 2024 | Marine Ecosystem Protected 2023–2024 |
| Canada marine and coastal areas conserved | 17.65%; 1,015,018 km² | May 2026 | Canada’s existing and proposed marine protected and conserved areas |
Australia’s national snapshot reported 52% marine protected area coverage, or about 4.6 million km². About 24% of Australian waters—2.2 million km²—was in highly protected no-take areas. The Collaborative Australian Protected Areas Database 2024 recorded 319 Australian marine protected areas plus 11 Sea Country Indigenous Protected Areas. On 30 June 2024, the combined marine protected areas in that database covered 48.9% of Australian waters.
The Australian Marine Parks were a major component of the national snapshot. Australia’s 60 Australian Marine Parks covered 3.8 million km², or 43% of Australian waters. The difference between 43%, 48.9%, and 52% reflects the different national snapshots and definitions reported by the sources and dates above; they should not be collapsed into one figure.
New Zealand had 44 marine reserves covering approximately 17,178 km² on 1 July 2024. Those reserves covered 9.5% of the area inside the 12-nautical-mile territorial-sea limit. New Zealand also had nine marine-mammal sanctuaries in the 2023–2024 reporting period. The sanctuaries covered 47,811 km², equal to 21.6% of its territorial sea.
After overlaps were removed, New Zealand’s marine reserves and marine-mammal sanctuaries together covered 59,829 km², or 28.2% of its territorial sea, on 1 July 2024. The distribution of marine-reserve area was highly uneven: 96.4%, or 16,558 km², lay within the Kermadec Islands and Subantarctic Islands bioregions, while the remaining 3.6%, or 620 km², occurred around mainland coasts.
Canada reported 17.65% of its marine and coastal areas conserved as of May 2026, equal to 1,015,018 km². Separately, Canada had 16 Oceans Act marine protected areas covering more than 600,000 km², roughly 10% of its marine and coastal areas, according to the Marine Protected Areas across Canada source. The two Canadian measures use different categories: conserved areas are broader than the Oceans Act marine protected area count.
United States coverage
The National Marine Protected Areas Center reported marine protected areas covering 26% of U.S. waters in its current snapshot accessed in 2026. Its inventory description cataloged nearly 1,000 marine protected areas. A separate NOAA marine protected area overview reported more than 1,600 sites spanning ocean, coastal, intertidal, estuarine, and Great Lakes habitats.
The NOAA overview reported that about 41% of U.S. marine waters were protected in some way, while highly protected no-take marine protected areas accounted for about 3% of U.S. marine waters. The 26% and 41% figures come from different current descriptions and should be retained as separate reported snapshots rather than presented as a time series.
The distribution of U.S. area was especially concentrated. In the 2022 scientific synthesis, A Scientific Synthesis of Marine Protected Areas in the United States: Status and Recommendations, the 50 largest U.S. marine protected areas represented 99.7% of total U.S. MPA area, totaling 3.19 million km². More than 96% of the area in those 50 largest sites was in the central Pacific. These figures explain why national area totals can be strongly influenced by a relatively small number of very large sites.
Canadian protected-area size examples
Canada’s national totals include very large individual sites. The Marine Protected Areas across Canada source listed Tuvaijuittuq at 319,411 km² when established in 2019. Tang.ɢ̱wan – ḥačxwiqak – Tsig̱is covered 133,017 km² when established in 2024.
Two sites listed under interim protection designations in 2026 were also substantial. Sarvarjuaq covered 73,700 km², while Qikiqtait covered 42,700 km². These site-level figures are not forecasts: they describe the areas associated with the stated establishment or interim-protection periods.
Taken together, the statistics show why marine protected area coverage needs several measures. Global mapped coverage reached 8.44% in 2024, while the 30% target still had a 21.56-point gap. Biodiversity-priority coverage improved, but 32% of Key Biodiversity Areas had no formal coverage. Implementation, protection strength, management-effectiveness evidence, and governance reporting each covered smaller portions of the ocean than the designation totals. National snapshots add further variation because their geographic limits, categories, and measurement dates differ.