An extensive tabular database is maintained by the Natural
Heritage Program. Other data that can be accessed include
element occurrence identification number.
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 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unpublished literature, and field surveys by volunteers,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
LIMITATIONS OF POINT LOCATION DATA
The point locations contained in the CGIA database represent occurrences
of species or communities which cover varying areas,
and their boundaries may or may not be known. The points
represent the centroid of the area covered, to the extent
that it is known. Some occurrences may extend several
miles from their centers.
The element occurrence database contains data from a variety
of sources, which vary in the quality of their locational
information. Some centroid points may be as much as several
miles off, though most are closer and many are exact to within
one or two seconds of latitude or longitude.
The precision of record is indicated in the Natural Heritage
Program databases. Because of uncertainty about the precision
and accuracy of source data, and because the aerial extent of
occurrences is not indicated on CGIA maps, occurrences 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
element occurrence, on the nature of the species or community,
and on the nature of the action being considered. Interpretation
of potential effects should be done only by biologists familiar
with the element, 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 majority of the
state has never been systematically surveyed for rare species
or natural communities. In addition, negative surveys are
seldom reported to the Natural Heritage Program and are not
recorded. The database reflects only locations where an element
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 element location 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.
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 rare species and community locations
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 CGIA database. Records are kept in the database until
the destruction of an occurrence is confirmed. Thus, some of
the records are likely to represent locations where an element
has not been seen in many years and may no longer be present.
Additional information about databases, elements of natural
diversity, and user services is available from the Natural
Heritage Program. The basic data are "public records" and
are available for inspection on request for reasonable purposes.
>system filename: nheo file size - 1.59MB
>Revisions and updates to this layer include:
>28.) filename: nheo0104 - NHEO layer updated February 19, 2004
>Total number of points = 23,291
>27.) filename: nheo1003 - NHEO layer updated October 28, 2003.
>Total number of points = 22,995.
>26.) filename: nheo0102 - NHEO layer updated January 28, 2002.
>Total number of points = 21,454.
>25.) filename: nheo1101 - NHEO layer updated November 8, 2001.
>Total number of points = 21,428. THIS VERSION WAS NOT
>RELEASED to the DATABASE, ONLY ARCHIVED.
>24.) filename: nheo101 - NHEO layer updated Jan 17, 2001.
>Total number of points = 21,115.
>23.) filename: nheo700 - NHEO layer updated July 20, 2000.
>Total number of points = 20,830.
>22.) filename: nheo300 - NHEO layer updated March 6, 2000.
>Total number of points = 20,170.
>21.) filename: nheo1199 - NHEO layer updated November 2, 1999.
>Total number of points = 19,416.
>20.) filename: nheo599 - NHEO layer updated May 21, 1999.
>Total number of points = 19,067.
>19.) filename: nheo299 - NHEO layer updated Feb. 23, 1999.
>Total number of points = 18,802.
>18.) filename: nheo1098 Total number of points in October, 1998
>update - 17,370.
>17.) filename: nheo898.
>Total number of points in August, 1998 file = 17,202.
>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
>16.) filename: nheo398. Total number of points in
>March 20, 1998 file = 16,978.
>15.) filename: nheo298. Total number of points in
>February 20, 1998 file = 15,767.
>14.) filename: nheo297. Total number of points in
>February 4, 1997 file = 16,512.
>13.) filename: nheo1096. Total number of points in
>October 21, 1996 file = 16,635.
>12.) filename: nheo496 Total number of points in
>April 9, 1996 file = 15,088.
>11.) filename: nheo196 Total number of points in January 23,
>1996 file = 14,850.
>10.) filename: nheo995 (previously named nc.nheo995)
>Total number of points in September 26, 1995 file = 14,329.
>The items "SPROT" and "GISID" were added to the PAT.
>9.) filename: nheo595 (previously named nc.nheo595)
>Total number of points in May 11, 1995 file = 13,871.
>8.) filename: nheo1094 (previously named nc.nheo1094)
>Total number of points in October 18, 1994 file = 12,826.
>7.) filename: nheo594 (previously named nc.nheo594)
>Total number of points in May 26, 1994 file = 12,046.
>6.) filename: nheo294 (previously named nc.nheo294)
>Total number of points in February 18, 1994 file = 11,665.
>5.) filename: nheo1193 (previously named nc.nheo1193)
>Total number of points in
>November 1993 file = 10,785 (Decline in number of points is
>due to the deletion of the points which did not have recorded
>Lat/Long values or is due to species reclassification. If
>there is a question about a specific site location, contact
>the Natural Heritage Program.)
>4.) filename: nheo893 (previoulsy named nc.nheo893)
>Total number of points in August 1993 file = 12,252.
>3.) filename: nheo493 (previously named nc.nhp493)
>Total number of points in April 1993 file = 10,005.
>2.) filename: nheo192 (previously named nc.nhp192)
>Total number of points in January 31, 1992 file = 9,546.
>1.) filename: The first file was release in 1990 and was
>superseded by the 1/13/92 version. This file was not archived.
>Total number of points in 1990 file = 7,366 (unverified).