American Wetlands Month 2027 runs from Saturday, May 1, to Monday, May 31, 2027. The US Environmental Protection Agency (EPA) and its partners created the month in 1991 to celebrate wetlands and the work of protecting them.
This guide covers the dates, key wetland facts, the largest US wetlands, the main types, and how the month differs from World Wetlands Day on February 2.
Key takeaways
- American Wetlands Month is May every year; in 2027, it runs from Saturday, May 1, to Monday, May 31.
- EPA and its partners started the month in 1991.
- The lower 48 states have lost about half their wetlands since the 1780s, and losses sped up by 50% after 2009.
- World Wetlands Day is a separate, global day on February 2; in 2027, it falls on a Tuesday.
American Wetlands Month 2027 at a glance
- Dates: Saturday, May 1 – Monday, May 31, 2027.
- Started by: the EPA and federal, state, tribal, local, nonprofit, and private partners in 1991.
- Focus: how wetlands clean water, reduce flooding, and support wildlife.
- Related day: World Wetlands Day, Tuesday, February 2, 2027.
- Public holiday: no.
Table of Contents
When is American Wetlands Month 2027?
American Wetlands Month 2027 is May 1–31, 2027. It starts on a Saturday and ends on Memorial Day, Monday, May 31.
May is a busy month for nature observances. In 2027, it also includes World Migratory Bird Day on Saturday, May 8, and the International Day for Biological Diversity on Saturday, May 22.
How did American Wetlands Month start?
The EPA created American Wetlands Month in 1991, together with federal, state, tribal, local, nonprofit, and private partners (EPA). The month celebrates the role wetlands play in the nation’s environment and economy.
The EPA calls wetlands the “kidneys” of a watershed because they filter pollutants such as nitrates, phosphorus, and sediment out of water.
In 2011, the EPA carried out the first National Wetlands Condition Assessment, a survey of the health of tidal and nontidal wetlands, and released a second report during Wetlands Month 2023.
US wetland facts
Wetlands covered less than 6% of the lower 48 states in 2019, about half the area they covered in the 1780s, according to the US Fish and Wildlife Service.
| Fact | Figure |
|---|---|
| Share of the lower 48 states covered by wetlands (2019) | Less than 6% |
| Wetland area compared with the 1780s | About half |
| Vegetated wetlands lost, 2009–2019 | 670,000 acres, about the size of Rhode Island |
| Change in the rate of loss since 2009 | Up 50% |
| States with wetlands | All 50 |
The Fish and Wildlife Service published these figures in March 2024, in its report on wetland status and trends from 2009 to 2019.
What is the biggest wetland in America?
The Yukon-Kuskokwim Delta in Alaska is often named the largest wetland in the United States, at roughly 50,000 square miles, about the size of Louisiana (WorldAtlas).
In the lower 48 states, the best-known large wetlands are the Everglades in Florida and the Atchafalaya Basin in Louisiana, a vast river swamp on the Atchafalaya River.
Sources rank them differently depending on whether they count total area, swamp, or protected land.
What are the main types of wetlands?
The four common types of wetlands are marshes, swamps, bogs, and fens. Scientists also group wetlands into five larger systems by where they occur.
| Common type | What it is |
|---|---|
| Marsh | A wetland of grasses, reeds, and other soft-stemmed plants, fresh or salt water |
| Swamp | A wetland dominated by trees or shrubs, such as cypress swamps |
| Bog | A peat-forming wetland fed mainly by rain, with acidic water and mosses |
| Fen | A peat-forming wetland fed by groundwater, less acidic than a bog |
The five systems used in the US wetland classification are marine (open coast), estuarine (where rivers meet the sea), riverine (rivers and streams), lacustrine (lakes), and palustrine (inland marshes, swamps, bogs, and ponds). When people ask about the “five major wetlands,” they usually mean these five systems.
What is World Wetlands Day?
World Wetlands Day is a global observance on February 2 each year, marking the signing of the Convention on Wetlands in 1971. On August 30, 2021, the UN General Assembly made it an official UN day (Irish Wetlands Network).
The 2026 World Wetlands Day theme was “Wetlands and traditional knowledge: Celebrating cultural heritage.” The 2027 theme has not been announced. World Wetlands Day 2027 falls on Tuesday, February 2.
| American Wetlands Month | World Wetlands Day | |
|---|---|---|
| When | All of May | February 2 |
| Where | United States | Worldwide |
| Started | 1991, by the EPA and partners | Marks the 1971 Convention on Wetlands; UN day since 2021 |
| 2027 date | Saturday, May 1 – Monday, May 31 | Tuesday, February 2 |
American Wetlands Month ideas
The EPA suggests learning about wetlands, visiting one, and finding out what your state and local groups do to protect them. Ideas include:
- Visit a wetland: find one through your local parks department, a state natural resources agency, or the US Fish and Wildlife Service’s National Wetlands Inventory map.
- Go birdwatching: May is spring migration, and wetlands are some of the best places to see migrating birds.
- Join a cleanup: many groups run litter and invasive-plant cleanups along marshes and rivers in May.
- Teach a wetland lesson: classes can compare marshes, swamps, bogs, and fens, or test how wetlands filter water.
- Learn about local protection: read what your state and nearby tribes are doing to protect wetlands.
Other nature months and weeks in 2027 are listed in the Awareness Calendar 2027.
American Wetlands Month dates 2026 to 2031
| Year | American Wetlands Month | World Wetlands Day |
|---|---|---|
| 2026 | Friday, May 1 – Sunday, May 31 | Monday, February 2 |
| 2027 | Saturday, May 1 – Monday, May 31 | Tuesday, February 2 |
| 2028 | Monday, May 1 – Wednesday, May 31 | Wednesday, February 2 |
| 2029 | Tuesday, May 1 – Thursday, May 31 | Friday, February 2 |
| 2030 | Wednesday, May 1 – Friday, May 31 | Saturday, February 2 |
| 2031 | Thursday, May 1 – Saturday, May 31 | Sunday, February 2 |
Frequently asked questions
When is American Wetlands Month 2027?
American Wetlands Month 2027 runs from Saturday, May 1, to Monday, May 31, 2027.
Who started American Wetlands Month?
The EPA started American Wetlands Month in 1991 with federal, state, tribal, local, nonprofit, and private partners.
What is the theme of World Wetlands Day 2026?
The 2026 theme was “Wetlands and traditional knowledge: Celebrating cultural heritage.”
What is the biggest wetland in America?
The Yukon-Kuskokwim Delta in Alaska is often named the largest US wetland, at about 50,000 square miles.
What are the five major wetlands?
The five wetland systems are marine, estuarine, riverine, lacustrine, and palustrine. The four common types are marshes, swamps, bogs, and fens.
Why are wetlands important?
Wetlands filter pollutants from water, soak up floodwater, and give homes to fish, birds, and other wildlife.
