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Bird Area Criteria
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Important Bird Area Criteria Definitions


1. Species of Conservation Concern
Note: You will need to refer to the Species of Conservation Concern and the Population Estimates and Criteria Thresholds documents for assistance with Criteria 1a and 1b.

1a. State Endangered, Threatened, Special Concern Species
Description: Sites that regularly support significant breeding or non-breeding densities of one or more of the following species listed as endangered, threatened or special concern in the state of New Jersey and federally listed species.

Applies primarily to breeding or wintering sites, through regular migratory areas may be considered if known to be of exceptional importance.  Sites should be those where the species occurs or potentially occurs with some regularity, not areas of infrequent occurrence.

NJ Endangered Species
The site should have the presence of regular probable breeding activity or regular wintering of at least one of the species listed, and have been occupied within the last 5 years.

NJ Threatened Species
Colonial Species: The site should regularly have at least 1% of the state population in a season, and have been occupied within the last five years.
Solitary Species: The site should be one of 3-5 sites in the state with the highest regularly occurring numbers, and have been occupied within the last five years.

NJ Special Concern Species
Colonial Species: The site should regularly have at least 5% of the state population in a season, and have been occupied within the last five years.
Solitary Species: The site should regularly have at least 5% of the state population of two or more species listed below, and have been occupied within the last five years.

1b. Conservation Priority Species
Description: Species identified as conservation priorities through large-scale bird conservation plans and/or species that are considered conservation priorities by state experts but not listed as state Endangered, Threatened or Special Concern (Criterion 1a).

Colonial Species: The site should regularly have at least 5% of the state population in a season, and have been occupied within the last five years.
Solitary Species: The site should be one of 3-5 sites in the state with the highest regularly occurring numbers, and have been occupied within the last five years.


2. Regional Responsibility Species
Note: You will need to refer to the Regional Responsibility Species document for assistance with Criterion 2.

Description: This category is mainly meant to cover areas capable of supporting significant populations of bird species for which New Jersey has a high responsibility for long-term conservation, even if they are not currently declining or threatened.  These are species with a disproportionately high percentage of their total population in the Bird Conservation Regions (BCRs) comprising NJ. Selection of sites will be based on avian assemblages within the habitat community types found within BCRs.

Generally, a site will need to have at least the indicated number of the species within a given habitat type to be considered.  However, consideration will be given to sites that include a diversity of habitats, even if the individual habitat types do not meet the required number of species listed.


3. Significant Congregations
Description: Sites that regularly holds significant numbers of one or more species, breeding or in winter.  Significant numbers are not easily defined.  The following are suggested to provide some logical thresholds for site selection.  These numerical criteria (D1-5) are guidelines only and other factors (quality and location of habitat, distribution and importance of species, etc.) may be considered.  Except where indicated, numerical estimates should be based on a short period of time, e.g. one-time counts such as daily surveys -- not on cumulative totals.  Introduced, feral or superabundant species (Mute Swan, resident Canada Goose, Monk Parakeet, American Crow, European Starling, etc.) should not be counted.

3a. Waterfowl

The site regularly supports 500 or more waterfowl at inland sites or 5,000 or more at coastal sites, in winter and/or in migration (staging).  The designation "waterfowl" includes such birds as loons, grebes, cormorants, geese, ducks and moorhens.

3b. Gulls and Terns

The site regularly supports 250 or more terns or at least 10% of the state population of gulls in a season.  Human-made food sources for gulls (landfills, dumpsites, sewage outflows, etc.) will not be accepted as IBAs.

3c. Wading Birds

The site regularly supports 50 or more breeding pairs of wading birds or 100 or more roosting individuals.  The designation "wading birds" includes such birds as bitterns, herons, egrets and ibises.

3d. Exceptional Single Species Concentrations

The site regularly supports significant concentrations of a "colonial" species (i.e. winter roosts) but may not meet the thresholds above.  Such sites should support a higher proportion of a species statewide population than other similar areas.

3e. Exceptional Diversity

The site supports an exceptional diversity of bird species.  This would include sites that do not necessarily harbor large numbers of birds but that provide important habitat for more bird species than found at most sites.  No absolute thresholds have been set owing to the scarcity of quantitative data, but sites should be clearly unique from other sites in the area.


4. Significant Migrant Stopover/Flyover
Description: Sites may qualify on the basis of exceptionally high numbers of birds during migration or as "migrant traps" relative to the surrounding areas.  Strong consideration will be given to areas with consistently high overall species diversity or diversity within a particular group (e.g., warblers).

4a. Raptors
The site is regularly an important stopover site, "bottleneck" or migratory corridor for at least 3,000 raptors (seasonal total) during spring or fall migration.

4b. Shorebirds
The site is an important migratory stopover or seasonal concentration site for migratory shorebirds.  The site should have at least 5% of the Atlantic flyway population or at least 3,000 individuals.

4c. Landbirds
The site is an important migratory stopover or seasonal concentration site for migratory landbirds and supports an exceptional diversity of bird species during migration.  Thresholds may vary, but a site should be clearly unique from other sites in the area.


5. Long-term Research/Monitoring
Note: This is a secondary category, used to supplement or support a site nomination.  A site cannot be nominated as an IBA solely on the basis of long-term avian research.

Description: The site is a natural area where a long-term research and/or monitoring project is based that contributes substantially to ornithology and bird conservation.  These are generally sites with a distinguished record and/or unique potential for long-term research and monitoring or exceptional educational value.  There should be a minimum of 5 years of data collection, with data being summarized and available for public examination (i.e. via reports or peer-reviewed publications).  Such sites may occur in urban, suburban, rural, or other settings.