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IBAs supporting conservation concern species, such as Lesser Prairie-Chicken, are included among the list of 383 Global IBAs.

Courtesy USFWS

As the U.S. Partner for BirdLife International, Audubon has the responsibility for identifying and working to conserve a network of Important Bird Areas throughout the U.S. This network of sites is comprised of state level IBAs that are prioritized as continentally or globally significant by the U.S. IBA Committee, a panel of nationally recognized bird experts.

Audubon has a goal of determining all of the Global IBAs in the U.S. To view progress to date, see current list of Global and Continental Important Bird Areas.

It is expected that out of approximately 3,000 state level IBAs (encompassing approximately 15% of the U.S. or ~340 million acres) 1,500 will be significant at the continental level (encompassing approximately 10% of the U.S. or ~226 million acres) and 800 will be significant at the global level (encompassing approximately 7% of the U.S. or ~160 million acres). This effort to prioritize sites as globally or continentally significant will greatly enhance Audubon’s overall efforts to focus our conservation actions to achieve our conservation goals.

The IBA criteria are divided into four categories based on vulnerability and/or responsibility. By definition, Important Bird Areas are sites that support:

Jump ahead to IBA Criteria List

General criteria standards:

• The basic data needed to support the nomination of an IBA at the continental or global level is a reliable estimate of the number of birds of a particular species at a site, in a season, in a year.
• It is important to have species-specific count data in virtually all cases (with the exception of criterion A4iii). Moreover, for conservation planning purposes we need to know the seasonal importance of a site rather than just the count of birds in a given year.
• The conservation value of a site may change significantly over time due to changes in land use, pollution, or landscape-level changes that occur as a consequence of sprawl, for example. Therefore, we intend to monitor the continued value of each IBA to birds on a periodic basis (e.g. every five years) to determine if it continues to qualify as an IBA. For this reason it is important to report the counts of birds in a particular year rather than as an average over a number of years. Moreover, it is important that the identification of an IBA be based on relatively current data:
• In order to qualify as an IBA at the global or continental level, the data in a site nomination must be no more than 10 years old (or 15 years old in the case of Alaska, where site access is often particularly difficult and/or expensive).

Global Criteria

Click criteria codes to view details and application of each criterion.

A1 - Species of Global Conservation Concern (See List of Species)
A2 - Assemblage of Restricted-range species
A3 - Assemblage of Biome-restricted species
A4i - ≥1% biogeographic (N. Am.) population of a waterbird simultaneously; ≥5% over a season
A4ii - ≥1% global population of a seabird or terrestrial species simultaneously; ≥5% over a season A4iii - ≥ 20,000 waterbirds/ ≥10,000 seabirds [not currently applied in the U.S.]
A4iv - aerial bottleneck where ≥ 5% N.Am. population of a migratory waterbird, or ≥ 5% global population of a migratory seabird or terrestrial species passes during a season

Continental Criteria

Click criteria codes to view details and application of each criterion.

B1- Species of Continental Conservation Concern (See List of Species)
B2- [Not applicable at regional level]
B3- Assemblage of individuals/species concentrated in a Bird Conservation Region
B4i- ≥ 1% flyway/subspecies population of a waterbird simultaneously; ≥5% over a season
B4ii- ≥ 1% biogeographic (N. Am.) population of a seabird or terrestrial species simultaneously; ≥5% over a season
B4iv- aerial bottleneck where ≥5% flyway/subspecies population of a migratory waterbird, or ≥5% N. Am. population of a seabird or terrestrial species passes during a season

State Criteria

Contact individual state coordinators for details of state criteria.

D1-US State: State Species of Conservation Concern
D3-US State: Species in rare/unique habitat
D4i-US State: ≥ 1% State population
D4ii-US State: waterfowl (State defined)
D4iii-US State: wading birds (State defined)
D4iv-US State: seabirds/other colonial waterbirds (State defined)
D4v-US State: shorebirds (State defined)
D4vi-US State: raptors/season (State defined)
D4vii- US State: outstanding landbird stopover D5-US State: Research site

Updated November 2009