Marine & Coastal Areas

Summary Global Guidelines Technical and interactive resources

The importance of marine and coastal conservation

Oceans cover 71 per cent of the Earth’s surface, the largest realm on the planet. Marine and coastal ecosystems supply us with food, oxygen and jobs. They capture up to a quarter of our carbon emissions and protect us from storm surges. They are also likely the most biologically diverse of the earth’s realms.

But oceans are probably the most undervalued and least understood of our realms. Covering such vast areas and extending to great depths make it challenging to manage and monitor marine and coastal health. The threats to the marine and coastal realm are also highly complex, from overfishing to oil and gas exploration to pollution from our activities on land and at sea.

How to protect marine and coastal areas

Three distinct elements relating to Marine Protected Areas (MPAs) are significant here: conservation of coastal and near-shore waters, offshore waters still within a country’s Exclusive Economic Zone (EEZ) and therefore subject to decisions by national or subnational governments, and high seas MPAs, where international agreements need to be applied. The opportunities and challenges are very different.

There are many coastal and marine areas governed and managed by and with Indigenous peoples and coastal communities. These provide much experience in establishing and managing protected areas and areas that may be suitable as Other Effective Area-based Conservation Measures (OECMs) in coastal communities, including traditionally / locally conserved or managed areas that do not meet protected area definitions. Experience with Locally Managed Marine Areas, particularly in the Pacific, provides models that are being used in other coastal areas. Engaging fishing communities with area-based conservation planning is important, and is influenced by specification of user rights, participatory and inclusive planning, engagement of community leaders and the extent to which set-asides have been used traditionally.

Coastal protected areas are complicated from a reporting point of view because it is often difficult to decide where the “coast” begins, with many sites having terrestrial, freshwater and marine components; some refer instead to “coastal zone” areas. Given this, it is important to recognize the need for connectivity between inland water and marine conservation and the various designations outside protected areas and other effective area-based conservation measures (OECMs) such as fishery management areas, exclusive artisanal fishing areas (EAFAs), Indigenous and traditional territories, and spatial planning needs to take place at a broader scale, involving participation of multiple actors.


Nearshore waters within the EEZ often have a different but overlapping set of stakeholders, including fishing communities but also shipping and offshore energy operations such as wind power and oil drilling. Management of such sites may be challenging in that it will be more difficult to maintain oversight.

High seas protected areas are vital for 30×30 since the high seas represent 64 per cent of the marine surface. But despite many proposals, mechanisms for establishment and management are missing: how to set up, who manages and enforces, and who pays. The agreement in March 2023 on conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction, under the UN Convention on the Law of the Sea, will help; but many challenges remain.

There has been a recent trend to establish large-scale MPAs in offshore waters, often larger than 100,000 km2. MPAs in deeper waters are important to protect long-lived deep water marine species, especially fish, to protect spawning populations from damaging deep-sea trawling and to conserve or restore damaged deepwater biodiversity hot spots (e.g., seamounts, hydrothermal vents, deep cold-water corals).

Enabling factors and challenges

Challenges include reconciling conservation and ecosystem integrity with the interests of marine-based industries such as fisheries, addressing problems of partial conservation (e.g., MPAs that protect the water column but not the seabed), difficulties in monitoring both the marine environment and human use, particularly in offshore sites, uncertainty about application of OECMs in a marine context, jurisdictional complexity, multiple interests and the many implications of climate change. Fishing inside an MPA can significantly reduce (or effectively eliminate) its conservation value. Agreeing on a global definition of “sustainable use” in a marine context, and how this differs from the rest of the marine environment, is particularly important.

Guidelines for applying the IUCN protected area management categories to marine protected areas: second edition 

This resource provides supplementary information to the 2008 Guidelines for Applying Protected Area Management Categories, with a focus on applying that guidance to marine protected areas (MPA), and the authors state that this resource should be read in conjunction with the 2008 guidelines. There are several IUCN protected area management categories (Ia, Ib, II, III, IV, V, and VI) that have variations in their primary objectives and levels of protection. Firstly, to qualify for these categories, a potential MPA site must meet the IUCN definition of a protected area, as defined in the 2008 guidelines: “A protected area is a clearly defined geographical space, recognised, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values”, and in case of conflict with other goals, nature conservation needs to be the main purpose of the site. The relevant IUCN category can then be assigned based on the main management objective of the MPA, which must apply to at least 75% of the MPA. Once a governance type has also been assigned to these sites, they should be reported to the World Database on Protected Areas and the UN List of Protected Areas.

The publication contains seven main sections: 1. Introduction; 2. What is a marine protected area?; 3. Characteristics of the marine environment that affect protected area designation and IUCN category application; 4. The IUCN protected area management categories as applied to MPAs; 5. Applying the categories to different zones in an MPA; 6. Relationship between the categories and different activities; 7. Reporting to the World Database on Protected Areas and the UN List of Protected Areas.

Overall, the aim of this resource is to increase the accuracy and consistency of assigning and reporting the IUCN categories in relation to marine and coastal protected areas.

Key take aways:

  1. A potential marine protected area (MPA) must meet the 2008 IUCN definition of a protected area: “A protected area is a clearly defined geographical space, recognised, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values”.
  2. Once a site is known to meet the definition, it should be assigned to one of the IUCN protected area categories (Ia, Ib, II, III, IV, V, or VI) based on which category is most aligned with the primary management objective of the MPA, which needs to apply to 75% of the site.
  3. The primary distinction between MPAs and other area-based measures, such as fishery management areas, lies in the fact that the main objective of MPAs, regardless of their form, is the conservation of biodiversity.

Large-scale marine protected areas: guidelines for design and management

This resource provides guidance on the best available practices for large-scale marine protected areas (LSMPAs), which are defined in these guidelines as areas greater than 150,000 km². LSMPAs are an important part of achieving marine conservation goals and they provide numerous ecological, economic, and cultural benefits. However, they also face challenges such as achieving effective jurisdictional and interagency coordination, maintaining sufficient budgets, addressing stakeholder rights, conducting consistent research and monitoring, and providing surveillance and enforcement. LSMPAs are distinct from smaller MPAs as they encompass entire marine ecosystems and ecological processes, provide scientific baselines, and protect extensive cultural spaces.

The publication contains four main sections: 1. Introduction, which explains the role of governance in LSMPAs, why they are valuable, and the challenges they face; 2. Designing LSMPAs, which introduces what good design entails, includes internal and external considerations, as well as planning details; 3. Management Planning, which details considerations such as working with multiple jurisdictions, timelines, deciding the best management approach, engaging with the public, sustainable financing, and other details; 4. Managing LSMPAs, which describes what managing LSMPAs involves, the components of management, reassessing the legal framework, and other considerations. The publication also contains 28 related case studies.

Overall, the aim of this resource is to enhance the efficacy of LSMPAs to enable them to effectively contribute to global conservation objectives and also benefit people.

Key take aways:

  1. Large-scale marine protected areas (LSMPAs) are defined as areas greater than 150,000 km² in this resource and are distinctive from smaller MPAs as they encompass entire marine ecosystems, protect critical habitats of many migratory species, act as living laboratories, and protect extensive cultural spaces.
  2. LSMPAs have many benefits as they can promote and preserve biodiversity, protect cultural landscapes/seascapes, enhance food security, support international cooperation, and enhance protected area networks and national conservation strategies. However, existing managers consistently cite challenges such as achieving effective jurisdictional and interagency coordination, maintaining sufficient budgets and developing viable sustainable financing plans, addressing stakeholder rights, conducting consistent research and monitoring, and providing surveillance and enforcement.
  3. LSMPAs must be well-designed. The key considerations for designing an LSMPA include (a) assessing the most urgent needs and hiring qualified staff early, (b) prioritising hiring a qualified science or research coordinator, (c) building partnerships, (d) assessing relationships between governance and management entities, (e) utilising existing legislation first, (f) characterising the biophysical and social science aspects of the site in parallel, (g) employing systematic conservation strategies and adaptive management practices, (h) carefully listening to stakeholders, and (i) thoughtfully developing outreach materials for the site.


The IUCN Global Ecosystem Typology is the first-ever comprehensive classification framework for classifying and mapping all Earth’s ecosystems, which integrates their functional and compositional features.
The Marine Realm includes all connected saline ocean waters characterised by waves, tides and currents.
Marine Realm

United Nations Intergovernmental Conference on Marine Biodiversity of Areas Beyond National Jurisdiction.

Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) Marine Protected Area (MPA) Information Repository supports the submission, hosting, analysis and reporting of Marine Protected Area (MPA) project data in line with the requirements of the Scientific Committee and the reporting obligations of Members and the Secretariat contained in relevant conservation measures and Research and Monitoring Plans (RMPs).
CCAMLR MPA Information Repository

Protected Planet: Marine Protected Areas and OECMs
Over 70% of the surface of Earth is ocean, comprised of highly diverse ecosystems, and providing a wide range of marine ecosystem services that support human society, health and the economy. This website presents the most recent official coverage statistics for marine protected areas.
Protected Planet: Marine protected areas and OECMs

The Marine Protection Atlas integrates science-based assessments that measure progress toward protecting 30% of the global ocean in fully and highly protected areas by 2030.
Marine Protection Atlas


The Marine Protected Areas Guide: a science-based tool and framework to identify different types of MPAs and connect these types of MPAs with the outcomes they are expected to achieve.
MPA Guide

Blue Bonds for Ocean Conservation. TNC’s Blue Bonds for Conservation model helps governments unlock funding for conservation—and could benefit millions of people in coastal regions.
Blue Bonds

Marine Manager Portal

The Portal Bertarelli is a free online tool that provides decision-making support by providing accessible information on ocean conditions, biodiversity and human-use activity in near real-time. Applications can support marine spatial planning; marine protected area design, management and monitoring; and scientific research.

The Marine Manager Portal

Reef Resilience Network

A resource for managers to improve effective management of coral reefs and critical marine systems globally To ensure marine managers have access to the latest science and management strategies—and are challenged and inspired by new ideas—the Reef Resilience Network’s website ( places relevant and reliable information at their fingertips. Created and updated by global experts in coral reefs, climate change, management planning, communication, and more.