---
title: "ecoregions, bioregions, and flyways"
canonical_url: https://ensurance.app/guide/ecoregions-bioregions-and-flyways
markdown_url: https://ensurance.app/guide/ecoregions-bioregions-and-flyways.md
subtitle: "the largest places are drawn by climate, soil, and wings"
category: natural-capital
---

# ecoregions, bioregions, and flyways

*the largest places are drawn by climate, soil, and wings*

A **bioregion** is a large area defined by its living systems rather than by political borders: its climate, its landforms, its soils, and the plants and animals that go with them. One Earth, a nonprofit, publishes a global map of them. Its framework divides the planet into 185 bioregions, drawn by combining biomes with large-scale geological structures and groupings of ecoregions. A bioregion is generally larger than an ecoregion and smaller than a biogeographical realm.

Every spring, shorebirds that wintered in Australia and New Zealand fly north, stop to feed on the mudflats of the Yellow Sea, and fly on toward breeding grounds as far as the Arctic. The route they fly is a place too, one no surveyor and no climate map drew. The birds, the mudflats, and the forests and shrublands of the bioregions they cross already exist and already depend on each other, whether or not anyone names them. [**Ensurance**](/?from=guide) is how the place you name gets funded to keep working. It is not the place.

This post covers the three largest kinds of place in the series: the ones drawn by climate, by soil and living systems together, and by wings.

## three ways to draw a large place

| kind | drawn by | who draws it | the protocol's count |
|---|---|---|---|
| **ecoregion** | a distinct assemblage of natural communities and species | RESOLVE Ecoregions 2017: 846 terrestrial ecoregions in 14 biomes | 844 accounts in `.ecoregion` |
| **bioregion** | biomes, geology, and groups of ecoregions combined | One Earth: 185 bioregions | 186 accounts in `.bioregion` |
| **flyway** | the routes migratory birds use | flyway partnerships and councils | 10 accounts in `.flyway` |

The counts in the last column are from 26 October 2026. They sit near the published frameworks, but they are not a claim of an exact one-to-one match with either map.

### ecoregions

An **ecoregion** is the finest of the three. The 2017 RESOLVE map, published by Eric Dinerstein and colleagues in *BioScience*, divides the world's land into 846 terrestrial ecoregions grouped into 14 biomes, from tropical moist forests to tundra. Each one is an area with a characteristic set of species and natural communities. The Colorado Rockies forests and the Colorado Plateau shrublands are two of them.

### bioregions

A **bioregion** in One Earth's framework groups ecoregions into larger units that share a biome and a geological setting. One Earth built its map on top of the RESOLVE ecoregions, but the two are separate frameworks drawn for different purposes, not one strict hierarchy maintained by one body. The point of a bioregion is a size large enough to hold whole river systems and migrations, and coherent enough that people across it can recognize a shared landscape.

### flyways

A **flyway** is a migration corridor: the broad route a set of bird populations uses between breeding and wintering grounds, with the wetlands and coasts where they stop to feed. In North America, four administrative flyways, Atlantic, Mississippi, Central, and Pacific, organize the management of migratory birds, each with a council of state, provincial, and territorial wildlife agencies working with the U.S. Fish and Wildlife Service. Across Asia and the Pacific, the **East Asian–Australasian Flyway Partnership**, launched in 2006, brings together governments, intergovernmental bodies, conservation groups, and companies along a flyway that spans 22 countries, from Arctic Russia and Alaska to Australia and New Zealand.

None of these partnerships works with this protocol. They are named here because they did the drawing, and because they have kept these corridors in view for decades. The protocol made its ecoregion, bioregion, and flyway accounts from the published maps. No one who lives there asked for them, and they speak for no one.

## the same place, read at three sizes

Here are the largest places over the Colorado River, as live accounts in the catalog:

| size | place | account |
|---|---|---|
| ecoregion | Colorado Rockies forests, the high mountain conifers | [colorado-rockies-forests.ecoregion](/colorado-rockies-forests.ecoregion?from=guide) |
| ecoregion | Colorado Plateau shrublands, cold desert and canyon country | [colorado-plateau-shrublands.ecoregion](/colorado-plateau-shrublands.ecoregion?from=guide) |
| bioregion | Colorado Plateau and mountain forests | [colorado-plateau-mountain-forests.bioregion](/colorado-plateau-mountain-forests.bioregion?from=guide) |
| flyway | the Americas flyway, Arctic breeding grounds through the Americas | [americas.flyway](/americas.flyway?from=guide) |

The bioregion's own description says it "bridges plateau shrublands and mountain forest ecoregions across four corners and uinta flank," so the two ecoregion accounts sit inside it. The Americas flyway's account names the Great Salt Lake and the Salton Sea among its critical stopovers, so it passes over the same West at a size larger than either.

The non-US example sits on the other side of the Pacific. [east-asian-australasian.flyway](/east-asian-australasian.flyway?from=guide) is addressed to the corridor the shorebirds at the top of this post fly; in the account's own description, it is the "busiest shorebird flyway on earth," from the Yellow Sea mudflats to Australasia. Much of the Yellow Sea's tidal flat has been reclaimed for development over the past half century, and UNESCO's evaluation of the region names habitat loss as the likely main driver of declines in the shorebirds that stop there. The catalog also carries accounts at the finer size inside it, such as [yellow-sea-saline-meadow.ecoregion](/yellow-sea-saline-meadow.ecoregion?from=guide). Neither has a wallet deployed today, and neither do the two ecoregion accounts or the Americas flyway above; of the accounts in this post, only the bioregion has one. Each is a page, not a fund.

## what stays the same, and what changes

**What stays the same** is the account. A flyway that crosses 22 countries holds an account of exactly the same shape as [the 54-acre beaver wetland at Marble](/marble-wetlands-preserve.avlt?from=guide): an address that can hold and receive funds once a wallet is deployed, with a person confirming each action unless the keeper has switched on a program, addressed to the place and not to any government or owner inside it. Several accounts can serve the same bioregion. None of them represents it.

**What changes** is almost everything else:

- **Who keeps it.** A wetland has a land trust. A flyway has dozens of governments, hundreds of reserves, and the people who live beside each stopover.
- **How it is measured.** A wetland is walked. An ecoregion is mapped from satellites and field surveys. A flyway is counted at its stopovers, bird by bird, year after year.
- **How it fails.** A large place rarely fails all at once. A flyway can lose a single stopover and with it a share of the birds that depended on that one beach or mudflat.
- **What an account at this size is for.** Mostly, coordinating the smaller places inside it rather than doing the work itself.

That last point is where large places earn their accounts. Nobody restores a bioregion directly. People restore a parcel, a reach, a stopover. The large account names the whole those parcels belong to, so the person working on one stopover can see the others.

:::johnson
**some places are drawn by wings.**

Ecoregions, bioregions, and flyways are the largest places, and each can hold an account of the same shape as a single wetland.

[open the Americas flyway account →](/americas.flyway?from=guide)
:::

## large places and the people inside them

The word bioregion carries a long history of people organizing their lives and politics around a shared landscape. How that idea meets finance is its own post: [bioregional finance onchain](/guide/bioregional-finance-onchain?from=guide) covers it. This series makes a narrower point. A bioregion is a place, drawn at a large size, and it is the same kind of place as everything smaller inside it.

The honest limit of a large place is that no one can sign for it. A bioregion has no titleholder, no single council, and often no single country. An account addressed to it does not change that; it gives the many people already working inside it a shared address. The people who live in a bioregion govern it, through every government, tribe, council, and landowner that already has a say.

If your work is at this size, the useful question is which smaller places inside it you can act on, and which neighbors share the same flyway or bioregion. The [map at /explore](/explore?from=guide) shows accounts and some of the links between them.

## the last post in this series

The flyway is the largest place in this series. The last post turns from how a place is drawn to what it is for. [Every place is already for something](/guide/every-place-is-already-for-something?from=guide) picks up there. For the whole ladder from one tree to a flyway, start at [what counts as a place?](/guide/what-counts-as-a-place?from=guide)

If you work on a bioregion or a flyway and want to talk about the size that fits, [write to us](/contact?from=guide&topic=ppp-place) and name the place in the first line.

## frequently asked questions

### what is a bioregion?

A bioregion is a large area defined by its ecological systems, such as climate, landforms, soils, and species, rather than by political boundaries. One Earth's framework maps 185 bioregions worldwide, each generally larger than an ecoregion and smaller than a biogeographical realm.

### what is the difference between an ecoregion and a bioregion?

An ecoregion is an area with a distinct set of natural communities and species; the RESOLVE 2017 map lists 846 terrestrial ecoregions. A bioregion, in One Earth's framework, groups ecoregions into larger units that share a biome and geological setting. They are separate frameworks, not one official hierarchy.

### what is a flyway?

A flyway is a broad migration corridor used by bird populations between their breeding and wintering grounds, including the wetlands and coasts where they stop to feed. North America has four administrative flyways, and the East Asian–Australasian Flyway Partnership covers a route spanning 22 countries.

## sources

[One Earth, what is a bioregion](https://www.oneearth.org/what-is-a-bioregion/) — the definition and the 185-bioregion framework built on RESOLVE ecoregions.

Eric Dinerstein et al., "An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm," *BioScience* 67, no. 6 (2017): 534–545 — the RESOLVE map of 846 terrestrial ecoregions in 14 biomes.

[U.S. Fish and Wildlife Service, migratory bird program administrative flyways](https://www.fws.gov/partner/migratory-bird-program-administrative-flyways) — the four North American flyways and their councils.

[East Asian–Australasian Flyway Partnership](https://www.eaaflyway.net/) — the partnership, launched in 2006, and the 22 countries of the flyway.

[UNESCO World Heritage evaluation, migratory bird sanctuaries along the coast of the Yellow Sea–Bohai Gulf of China](https://whc.unesco.org/document/189222) — tidal flat loss and habitat loss as the likely main driver of shorebird declines on the flyway.

## the series

1. [what counts as a place?](/guide/what-counts-as-a-place?from=guide) — read first
2. [a single tree can be a place](/guide/a-single-tree-can-be-a-place?from=guide)
3. [the parcel is the place you can sign for](/guide/the-parcel-is-the-place-you-can-sign-for?from=guide)
4. [a watershed draws its own line](/guide/a-watershed-draws-its-own-line?from=guide)
5. [ecoregions, bioregions, and flyways](/guide/ecoregions-bioregions-and-flyways?from=guide)
6. [every place is already for something](/guide/every-place-is-already-for-something?from=guide)

## the three series

- [what counts as a place?](/guide/what-counts-as-a-place?from=guide) — place
- [what counts as a purpose?](/guide/what-counts-as-a-purpose?from=guide) — purpose
- [who counts as people?](/guide/who-counts-as-people?from=guide) — people
- [what do you want to ensure?](/guide/what-do-you-want-to-ensure?from=guide) — the series before these three