Bird Areas >
supporting conservation concern species, such as Lesser
Prairie-Chicken, are included among the list of Global
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.
has a goal of determining all of the Global IBAs in the U.S.
For more on the prioritization process, click
here. For progress to date, see list of Global
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:
1. Species of conservation concern (e.g. threatened and endangered species)
2. Range-restricted species (species vulnerable because they are not widely distributed)
3. Species that are vulnerable because their populations are concentrated in one general habitat type or biome
4. Species, or groups of similar species (such as waterfowl or shorebirds), that are vulnerable because they occur at high densities due to their congregatory behavior
Jump ahead to IBA Criteria List
General criteria standards:
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.
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.
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:
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).
site that meets at least one Global criteria is termed a Global
Important Bird Area.
below 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
meeting at least one Continental criteria and no Global Criteria
is termed a
Continental Important Bird Area. Click below 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
site solely meeting state level criteria is termed a State
Important Bird Area.
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:
on the Important Bird Area prioritization process...