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of information compiled from a broad range of sources including herbarium and museum collections, published and unpublished literature, and field surveys by volunteers, contracted workers, and staff.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 data.
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 information. 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.
DATA CURRENCY 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 CGIA database.
ADDITIONAL INFORMATION 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.
These data are intended for research or planning projects that will contribute to better protection for the ecological features involved. Due to its dynamic nature, this data becomes outdated very quickly. The Natural Heritage Program must be contacted before each use of the 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. Acknowledgement of products derived from this data set should cite the following: The source of the Significant Natural Heritage Areas data is the North Carolina Corporate Geographic Database. Earlier versions of this data set may exist. The user must be sure to use the appropriate data set for the time period of interest. While efforts have been made to ensure that these data are accurate and reliable within the state of the art, CGIA cannot assume liability for any damages or misrepresentation caused by any inaccuracies in the data or as a result of changes to the data caused by system transfers.