A marine protected area (MPA) is a section of the ocean where a government has placed limits on human activity. Many MPAs allow people to use the area in ways that do not damage the environment. Some ban fishing. A few do not allow people to enter the area at all.

MPAs have been established because the ocean and the things that live in it face many dangers. Threats to the ocean include overfishing, litter, water pollution, and global climate change. These threats have caused a decline in the population of many fish, marine mammals, and other sea creatures.

Marine protected areas can have many different names, including marine parks, marine conservation zones, marine reserves, marine sanctuaries, and no-take zones. More than 5,000 MPAs have been established around the world. Together, they cover 0.8 percent of the ocean.

Marine protected areas can be established in a variety of aquatic habitats. Some MPAs are in the open ocean. Many MPAs protect coastlines. Others cover estuaries, places where rivers enter the sea. In estuaries, freshwater and saltwater mix. Some freshwater habitats, including protected areas in the Great Lakes, are also considered MPAs.

Goals of MPAs

Different MPAs have different goals. The main focus of many MPAs is to protect marine habitats and the variety of life that they support. For example, the Galápagos Marine Reserve, which lies about 1,000 kilometers (600 miles) off the west coast of South America, protects a series of small islands and the surrounding waters. This reserve includes a tremendous variety of habitats, from coral reefs to cold ocean currents to mangrove swamps, where trees grow directly in salty seawater. The waters around the Galápagos are home to 3,000 different plant and animal species, including unusual species such as the marine iguana, the world’s only seagoing lizard.

Some MPAs focus on conserving historic sites such as shipwrecks. The USS Monitor was a warship that sank in a storm off the coast of North Carolina during the Civil War. In 1975, the USS Monitor National Marine Sanctuary was established to protect the remains of the ship. It was the nation’s first national marine sanctuary.

Other MPAs are established in order to ensure that resources are sustainable—that they will not run out. By having limits that prevent overfishing, these MPAs ensure that fish can reproduce and maintain healthy populations. This enables people to fish year after year, maintaining their way of life. Georges Bank, off the coast of New England and Nova Scotia, Canada, was once one of the world’s greatest fisheries. But it was heavily fished for centuries, and populations of cod, haddock, flounder, and other species plummeted. After several MPAs were established by the United States and Canada, fish populations began to increase, and fishing improved.

Levels of Protection

Different MPAs provide different levels of protection. The strictest type of MPA allows no human entry at all. This not only prevents people from fishing, but also prevents people from disturbing delicate habitats. No-entry MPAs tend to be small and are often used for research. Parts of the vast Seaflower Reserve off Colombia’s Caribbean coast ban all human access.


Other MPAs are less strict. In a no-take MPA, fishing and collecting are not allowed, but people can travel through the area and use it for recreation, such as snorkeling or swimming. All of Laughing Bird Caye National Park, which protects a small island 18 kilometers (11 miles) off the coast of Belize in Central America, is a no-take MPA.

In multiple-use MPAs, the area is protected, but some fishing is allowed. Many national parks, such as Acadia National Park in the U.S. state of Maine, are multiple-use MPAs.

Many MPAs are divided up into different zones. In some zones, fishing is allowed, while in other zones, people might not be permitted entry at all. Australia’s Great Barrier Reef is the site of one of the world’s largest MPAs. The Great Barrier Reef Marine Park is divided into zones. Some of these zones allow recreational and commercial fishing. About one-third of the park has strict rules against fishing. Since these zones were put in place, the numbers of fish and corals have increased.

Establishing an MPA

National governments establish many MPAs. State, local, and tribal governments also establish MPAs. For example, the U.S. state of California has established the Point Lobos State Marine Reserve to protect underwater canyons and kelp forests. The Quileute Tribe of the U.S. state of Washington works with the federal government to keep the Olympic Coast National Marine Sanctuary a sustainable fishery.

Sometimes, national governments work together to establish an MPA that crosses borders. Italy, France, and Monaco together established the Pelagos Sanctuary for Mediterranean Marine Mammals. It covers parts of sea that is in the nations’ own territories as well as international waters.

At some MPAs, the level of protection remains the same year-round. At others, people are only barred from an area during certain seasons, often when vital species are breeding. For example, in the Irish Sea, fishing is controlled during cod spawning season, when the fish produce and fertilize eggs. This helps conserve the cod population.

The Importance of Marine Protected Areas (MPAs)
Sea turtles and other large marine creatures are often found in marine protected areas.

The Big and the Small
The world's largest MPA is Phoenix Islands Protected Area. Part of the tiny nation of Kiribati, it lies in a remote part of the Pacific Ocean. The Phoenix Islands Protected Area stretches across 410,500 square kilometers (158,453 square miles), an area the size of California. The MPA includes eight small islands, two coral reef systems, and large swaths of deep ocean. Only a handful of people live on the islands, so it is a nearly pristine habitat for teeming populations of birds, fish, and other marine life.

The world's smallest MPA is Echo Bay Marine Provincial Park in British Columbia, Canada. It covers just 0.4 hectares (1 acre) and is a popular spot for ocean kayakers to pull ashore.

MPA Catastrophe
According to the National Oceanic and Atmospheric Administration (NOAA), 53 U.S. MPAs are in the proximity of the 2010 Deepwater Horizon oil spill in the Gulf of Mexico.

aquatic
Adjective

having to do with water.

ban
Verb

to prohibit or not allow.

Noun

natural or artificial line separating two pieces of land.

breed
Verb

to produce offspring.

Noun

deep, narrow valley with steep sides.

century
Noun

100 years.

Civil War
Noun

(1860-1865) American conflict between the Union (north) and Confederacy (south).

Noun

gradual changes in all the interconnected weather elements on our planet.

coastline
Noun

outer boundary of a shore.

cod
Noun

popular food fish native to the North Atlantic Ocean.

commercial fishing
Noun

industry responsible for catching and selling fish.

conserve
Verb

to save or use wisely.

Noun

tiny ocean animal, some of which secrete calcium carbonate to form reefs.

coral reef
Noun

rocky ocean features made up of millions of coral skeletons.

Noun

steady, predictable flow of fluid within a larger body of that fluid.

damage
Noun

harm that reduces usefulness or value.

decline
Verb

to reduce or go down in number.

delicate
Adjective

fragile or easily damaged.

disturb
Verb

to bother or interfere with.

environment
Noun

conditions that surround and influence an organism or community.

establish
Verb

to form or officially organize.

Noun

mouth of a river where the river's current meets the sea's tide.

federal
Adjective

having to do with a nation's government (as opposed to local or regional government).

fertilize
Verb

to make productive or fertile.

fish
Verb

to catch or harvest fish.

fishery
Noun

industry or occupation of harvesting fish, either in the wild or through aquaculture.

flounder
Noun

popular food fish with a flat body.

freshwater
Noun

water that is not salty.

Georges Bank
Noun

(37,500 square kilometers/14,480 square miles) fishing ground extending from off the U.S. state of Massachusetts to off Nova Scotia, Canada.

government
Noun

system or order of a nation, state, or other political unit.

Great Lakes
Noun

largest freshwater bodies in the world, located in the United States and Canada. Lake Huron, Lake Ontario, Lake Michigan, Lake Erie, and Lake Superior make up the Great Lakes.

Noun

environment where an organism lives throughout the year or for shorter periods of time.

haddock
Noun

popular food fish native to the north Atlantic Ocean.

hectare
Noun

unit of measure equal to 2.47 acres, or 10,000 square meters.

increase
Verb

to add or become larger.

Noun

body of land surrounded by water.

kelp forest
Noun

underwater habitat filled with tall seaweeds known as kelp.

litter
Noun

trash or other scattered objects left in an open area or natural habitat.

lizard
Noun

reptile, usually with four legs and scales.

mangrove swamp
Noun

coastal wetland dominated by mangrove trees, which have roots that can survive in salty water.

marine conservation zone
Noun

area of the ocean set aside for protection of aquatic ecosystems.

marine iguana
Noun

lizard native to the Galapagos Islands.

marine mammal
Noun

an animal that lives most of its life in the ocean but breathes air and gives birth to live young, such as whales and seals.

Noun

part of the ocean protected by the government to preserve a threatened ecosystem or habitat. Marine parks are often recreational areas.

marine protected area (MPA)
Noun

area of the ocean where a government has placed limits on human activity.

Noun

part of the ocean where no fishing, hunting, drilling, or other development is allowed.

Noun

part of the ocean protected by the government to preserve its natural and cultural features while allowing people to use and enjoy it in a sustainable way.

multiple-use MPA
Noun

marine protected area that allows different levels of human activity, usually by zones.

national park
Noun

geographic area protected by the national government of a country.

New England
Noun

area in the United States comprising the states of Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont.

Noun

area set aside by the government where all extractive activity, including fishing, mining, and drilling, is not allowed.

Noun

large body of salt water that covers most of the Earth.

open ocean
Noun

area of the ocean that does not border land.

overfish
Verb

to harvest aquatic life to the point where species become rare in the area.

Phoenix Islands Protected Area
Noun

(408,250 square kilometers/157,626 square miles) largest marine protected area in the Pacific Ocean.

plummet
Verb

to fall sharply.

population
Noun

total number of people or organisms in a particular area.

pristine
Adjective

pure or unpolluted.

Quileute
Noun

people and culture native to the western part of the U.S. state of Washington.

recreation area
Noun

specific area that allows camping, boating, fishing, diving, kayaking, picnicking, and other activities.

remote
Adjective

distant or far away.

reproduce
Verb

to create offspring, by sexual or asexual means.

research
Noun

scientific observations and investigation into a subject, usually following the scientific method: observation, hypothesis, prediction, experimentation, analysis, and conclusion.

resource
Noun

available supply of materials, goods, or services. Resources can be natural or human.

Noun

large stream of flowing fresh water.

seagoing
Adjective

able to use the ocean for travel.

shipwreck
Noun

remains of a sunken marine vessel.

snorkel
Verb

to swim underwater using a simple tube to breathe air above the surface.

spawn
Verb

to give birth to.

strict
Adjective

always or almost always following limits, rules, or regulations.

sustainable
Adjective

able to be continued at the same rate for a long period of time.

swath
Noun

path or line of material.

swim
Verb

to move while entirely or mostly in the water.

teem
Verb

to overflow or be full of.

Noun

degree of hotness or coldness measured by a thermometer with a numerical scale.

tremendous
Adjective

very large or important.

USS Monitor
Noun

(1862) first ironclad warship built for the U.S. Navy.

vital
Adjective

necessary or very important.

warship
Noun

seagoing vessel built for armed conflict.

water pollution
Noun

introduction of harmful materials into a body of water.

whale
Noun

largest marine mammal species.

Noun

area separated from others by artificial or natural divisions.