Natural Heritage Element Occurrences

Title: Natural Heritage Element Occurrences
Abstract:: 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 digital Natural Heritage Element Occurrences data for research or planning projects that will contribute to better protection for the ecological features involved. The file enables the user to identify locations of rare and endangered species populations and occurrences of exemplary or unique natural ecosystems (terrestrial and palustrine) and special wildlife habitats. This file covers the state of North Carolina. Due to its dynamic nature, this data becomes outdated very quickly.
Supplemental_Information:: 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of information compiled from a broad range of sources including herbarium and museum collections, published and unpublished literature, and field surveys by volunteers, contracted workers, and staff.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 NC OneMap 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 DATA 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. 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 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 NC OneMap datalayer. 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 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. Beginning with the May 16, 2008 version quite a few low precision, county-level element occurrences were replaced with more precise locations. There was a large drop in acreage from the previous version, but loss of acreage in the NHEO layer should not be interpreted as loss of habitat. The relatively few low precision records in the coverage will dominate the acreage total, and any changes in these will obscure any acreage trends. The trend of replacing low precision records with higher precision will continue in future versions. That doesn't guarantee that the number of low precision records will continually go down, though, since NHP may start tracking a new species which has only poor data initially.
Revisions and updates to this layer include: 7.) NHEO layer updated May 16, 2008. 6.) NHEO layer updated February 1, 2008. Data are now stored in one dataset. Points and lines are buffered and put into this polygon dataset. 5.) NHEO layer updated November 27, 2007. 4.) NHEO layer updated February 27, 2007. 3.) NHEO layer updated August 16, 2006. 2.) NHEO layer updated December 2005. 1.) NHEO layer updated September 7, 2005. Data are now stored in three datasets: lines, polygons, and points.

Value	Definition
Very High ( >95% )	Greater than 95%.
High ( >80%, <=95% )	Between 80% and 95%.
Medium ( >20%, <=80% )	Between 20% and 80%.
Low ( >0%, <=20% )	Less than 20%.
Unknown	Percentage is unknown.
(Blank)	Occurrence is not ranked.

Value

Definition

Very High ( >95% )

Greater than 95%.

High ( >80%, <=95% )

Between 80% and 95%.

Medium ( >20%, <=80% )

Between 20% and 80%.

Low ( >0%, <=20% )

Less than 20%.

Unknown

Percentage is unknown.

(Blank)

Occurrence is not ranked.

Value	Definition
Extant	The occurrence is known to still exist.
Historic	Information for an occurrence is old or recent surveys failed to find it, but there is no evidence it is destroyed.
Destroyed	The occurrence is known to be destroyed.
Unranked	The occurrence is not ranked.

Value

Definition

Extant

The occurrence is known to still exist.

Historic

Information for an occurrence is old or recent surveys failed to find it, but there is no evidence it is destroyed.

Destroyed

The occurrence is known to be destroyed.

Unranked

The occurrence is not ranked.

Value	Definition
Vertebrate Animal	Includes mammals, birds, reptiles, amphibians, and fishes.
Invertebrate Animal	Includes mollusks,arachnids, crustaceans, and insects.
Vascular Plant	Includes dicots, monocots, gymnosperms, ferns, and fern allies.
Nonvascular Plant	Includes mosses, liverworts, hornworts, and lichens.
Natural Community	A distinct and reoccurring assemblage of populations of plants, animals, bacteria, and fungi naturally associated with each other and their physical environment.
Animal Assemblage	A concentration of animal species using the same site for a phase of their life cycle (feeding, reproduction, migration, hibernating, etc) e.g. bird colonies, bat or reptile lubernacula, concentrations of migrating shorebirds, multispecific spawning grounds, or multispecific mussel habitats.

Value

Definition

Vertebrate Animal

Includes mammals, birds, reptiles, amphibians, and fishes.

Invertebrate Animal

Includes mollusks,arachnids, crustaceans, and insects.

Vascular Plant

Includes dicots, monocots, gymnosperms, ferns, and fern allies.

Nonvascular Plant

Includes mosses, liverworts, hornworts, and lichens.

Natural Community

A distinct and reoccurring assemblage of populations of plants, animals, bacteria, and fungi naturally associated with each other and their physical environment.

Animal Assemblage

A concentration of animal species using the same site for a phase of their life cycle (feeding, reproduction, migration, hibernating, etc) e.g. bird colonies, bat or reptile lubernacula, concentrations of migrating shorebirds, multispecific spawning grounds, or multispecific mussel habitats.

Data format:	ESRI shapefile (*.shp)
Network links:	NC OneMap

Data format:

ESRI shapefile (*.shp)

Network links:

NC OneMap

Natural Heritage Element Occurrences

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