The North Carolina Department of Environment and
Natural Resources, Division of Parks and Recreation, Natural Heritage
Program in cooperation with the NC Center for Geographic Information &
Analysis, developed the Significant Natural Heritage Areas digital data
to determine the areas containing ecologically significant natural
communities or rare species.
NOTE: Due to its dynamic nature, this data becomes outdated very quickly.
The Natural Heritage Program MUST be contacted before each use of this
data set, to ensure data currency. The Natural Heritage Program MUST
be contacted in writing prior to distribution or hardcopy output of
this data layer. This data covers the state of North Carolina. This
data covers statewide NC.
An extensive tabular database is maintained by the Natural
Heritage Program. Other data that can be accessed include
natural area identification code.
Supplemental materials are also available that indicate the
state, national and global status of the rare plants and animals
of North Carolina. These publications
are available from the NHP and are helpful in understanding
each natural heritage site record. (SEE CROSS REFERENCES)
NATURAL HERITAGE PROGRAM DATA
The Natural Heritage Program is the state's most comprehensive
source of information on rare and endangered animals and
plants, and exemplary natural communities, known collectively
as "elements of natural diversity." Since 1976, the program
has systematically gathered information on the occurrence and
the status of the state's ecological resources. The inventory
consists of information compiled from a broad range of sources
including herbarium and museum collections, published and
unpublished literature, and field surveys by volunteers,
contracted workers, and staff. Information from and
interpretation of this database for specific sites is available
from the Natural Heritage Program. This is generally the
preferred method of getting information on elements of natural
diversity. The geographic content of the Natural Heritage
Program element occurrence database has also been incorporated
into the state Center for Geographic Information & Analysis
(CGIA) ARC/INFO database where it can be combined with other geographic
data for planning and analysis. Users of the data
must, however, be aware of the nature and limitations of the
LIMITATIONS OF POLYGON DATA
The polygon locations contained in the CGIA database represent
the approximate boundaries of ecologically significant natural areas.
The natural areas database contains data from a variety of
sources, which vary in the quality of their locational
Because of uncertainty about the precision and accuracy of
source data, polygons anywhere within several
miles of a site of interest should be regarded as indicating
the need for more information. Probability of effects by a
project depends on the actual location and extent of the natural
area, on the nature of the species or community it contains, and on
the nature of the action being considered. Interpretation of
potential effects should be done only by ecologists familiar
with the natural area, with the best locational information available.
LIMITATIONS OF ABSENCE OF DATA
Although the Natural Heritage Program has conducted numerous
biological inventories and has assembled as much of the
secondary source data as possible, the large majority of the
state has never been systematically surveyed for significant
natural areas. In addition, negative surveys are
seldom reported to the Natural Heritage Program and are not
recorded. The database reflects only locations where a significant
natural area was once known to occur. It does not distinguish
between areas known to have no elements and those that have
not been checked. The absence of natural areas cannot be
taken as an indication of absence of elements or of ecological
concerns. Natural Heritage Program biologists are often able
to give indications of the potential for concern in unsurveyed
areas, and the CGIA map database is not a substitute for this
kind of interpretation.
The Natural Heritage Program databases are continually updated
as new information is acquired. The locational database at
CGIA is updated as needed for applications. Users should
determine from CGIA the date of the last update and, if
necessary, see that an update is done prior to their application
being run. All printed maps from the GIS should be dated.
Depending on activity in a given area, a map may quickly become
outdated, or may remain current for several years. It is not
possible to set a specific expiration date on maps; however,
data more than six months old should not be depended on without
checking with the Natural Heritage Program.
Only a small portion of the natural areas
are monitored on a regular basis. Information in the Natural
Heritage Program database represents the occurrence at the last
time it was observed. The date of last observation is given in
the Natural Heritage Program database but is not included in the
Additional information about significant natural heritage areas,
and user services are available from the Natural
Heritage Program. The basic data are "public records" and
are available for inspection on request for reasonable purposes.
>system filename: snha file size = 14.4 MB
>Revisions and updates to this layer include:
>15.) filename: snha0104 - Coverage updated January 13, 2003.
>14.) filename: snha1003 - Coverage update October 28, 2003.
>13.) filename: snha0102 - Coverage update January 28, 2002.
>12.) filename: snha1001 - Coverage update October 29, 2001.
>THIS VERSION NOT RELEASED, JUST ARCHIVED.
>11.) filename: snha101 - Coverage update January 17, 2001. 1,897
>polygons. Arc attributes were dropped since they were only default
>10.) filename: snha700 - Coverage update July 20, 2000. 1,838 polygons.
>9.) filename: snha300 - Coverage updated March 6, 2000. 1,881 polygons.
>8.) filename: snha1199 - November 1, 1999 update. 1,994 polygons.
>7.) filename: snha599 - May 21, 1999 update. Data set contains 1,992
>6.) filename: snha299 The Feb. 26, 1999 file contains 2,012 polygons.
>5.) filename: snha898 - August 3, 1998 update.
>The August 1998 update to this layer consisted of
>projecting the data from NAD27 datum, State Plane
>projection, units of measure feet TO: NAD83 DATUM,
>State Plane PROJECTION, UNITS OF MEASURE METERS.
>This was done to comply with the NC Geographic
>Information Coordinating Council's "Statement of
>Direction for North Carolina Corporate Geographic
>Database Horizontal Reference, Datum and Unit of
>Measure". This reprojecting was done in
>various ways depending on the data type and content.
>Vector data was projected using the 'project' command
>in ESRI's Arc software and topology was cleaned and
>built based on coverage needs. Raster data was
>projected using ESRI's Grid module and various steps
>4.) filename: snha298 - February 26, 1998 update. Item PRIORITY changed
>to SIG in .pat. Item ACRES added to .pat. Item MACROCD changed to
>MCSITECODE. Arc attribute table (.aat) was dropped.
>This layer was previously named Natural Areas, nanhp.
>3.) filename: nanhp1096 - October 21, 1996 update. Areas may have
>been added, deleted or attributes corrected.
>2.) filename: nanhp596 - May 20, 1996 release of Natural Areas for
>statewide North Carolina. This incorporated the previous data,
>edits, edition and expansion of the coverage area.
>1.) filename: ap24.nar793 Natural Areas for the APES region.
>The July 1993 file is the original
>version of this data and covers only the APES area minus Tyrrell
>and Dare counties.