Metadata
Description of CNDDB fields

(In alphabetical order)

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

 


Accuracy   (Occurrence field)

Accuracy refers to the precision or accuracy level of a given spatial feature.  Accuracy represents spatial uncertainty in a relative way on a scale of one to ten (from most accurate to least accurate).  Non-specific polygons and circles of increasing size indicate progressively less precise source data.  Larger circles do NOT represent larger occupied areas, but rather greater uncertainty of the EO's exact location.

Accuracy Level Description
1 Specific bounded area with an 80 meter radius.  Per Heritage methodology, this is considered a point.
2 Specific bounded area (non-circular)
3 Non-specific bounded area
4 Non-specific, circular feature with a 150 meter radius (1/10 mile)
5 Non-specific, circular feature with a 300 meter radius (1/5 mile)
6 Non-specific, circular feature with a 600 meter radius (2/5 mile)
7 Non-specific, circular feature with a 1000 meter radius (3/5 mile)
8 Non-specific, circular feature with a 1300 meter radius (4/5 mile)
9 Non-specific, circular feature with a 1600 meter radius (1 mile)
10 Non-specific, circular feature with a 8000 meter radius (5 miles)

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California Rare Plant Rank   (Element field)

The California Rare Plant Rank status applies to plants only.  The California Rare Plant Ranks are a ranking system originally developed by the California Native Plant Society (CNPS) to better define and categorize rarity in California's flora.  These ranks were previously known as the CNPS lists but were renamed to the California Rare Plant Ranks to better reflect the joint effort among the CNPS, the CNDDB, and a wide range of botanical experts, who work together to assign a rarity ranking.  All plants tracked by the CNDDB are assigned to a California Rare Plant Rank category.  These categories are:

CA Rare Plant Rank Description
1A Plants presumed extinct in California and rare/extinct elsewhere
1B.1 Plants rare, threatened, or endangered in California and elsewhere; seriously threatened in California
1B.2 Plants rare, threatened, or endangered in California and elsewhere; fairly threatened in California
1B.3 Plants rare, threatened, or endangered in California and elsewhere; not very threatened in California
2A Plants presumed extirpated in California, but more common elsewhere
2B.1 Plants rare, threatened, or endangered in California, but more common elsewhere; seriously threatened in California
2B.2 Plants rare, threatened, or endangered in California, but more common elsewhere; fairly threatened in California
2B.3 Plants rare, threatened, or endangered in California, but more common elsewhere; not very threatened in California
3.1 Plants about which we need more information; seriously threatened in California
3.2 Plants about which we need more information; fairly threatened in California
3.3 Plants about which we need more information; not very threatened in California
4.1 Plants of limited distribution; seriously threatened in California
4.2 Plants of limited distribution; fairly threatened in California
4.3 Plants of limited distribution; not very threatened in California

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Common Name   (Element field)

The Common Name of an element, recognized at the state level.  The Common Name value for natural communities is the same as that for Scientific Name.

 

County   (Occurrence field)

The County, or counties, that the element occurrence falls in. Some occurrences straddle the border of California, so this field may also contain the states of Arizona, Nevada and Oregon, as well as Mexico and the Pacific Ocean.

 

Date Element Last Seen   (Occurrence field)

According to submitted information, the most recent date that an observer actually saw the element at this site.  Format: YYYYMMDD.  Dates with XX to XXXXXXXX values depict undetermined or unknown values or dates.

 

Date Site Last Seen   (Occurrence field)

The most recent date that an observer visited the site, according to information available to the CNDDB staff.  Format: YYYYMMDD.  Dates with XX to XXXXXXXX values depict undetermined or unknown values or dates.

 

Detailed Location   (Occurrence field)

Detailed Location comments provide additional information about the location/distribution of an element occurrence; best read after Location.

 

Ecological Comments   (Occurrence field)

Ecological Comments on conditions at the mapped location.  This can include information on associated species, the physical characteristics of the site, etc.

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Element Code   (Element field)

The Element Code is a ten-character code assigned to each element by NatureServe for data management purposes.  These codes are common to all Natural Heritage Programs and Conservation Data Centers both within and outside of the United States and allow efficient inter-jurisdictional communication.  An outline of the upper levels of classifications is presented below.  Complete coding information is contained in the Natural Heritage Program Operations Manual, TNC, Arlington, Virginia, April 1982, revised June 1988.

First character Meaning
A Vertebrate animal
C Community (as in Natural Community or plant community)
I Invertebrate animal
N Non-vascular plant
P Vascular plant
O Other (State trees, etc.; not used in CNDDB)
G Geologic (not used in CNDDB)

Vertebrate Animals (bytes 1, 2, 3):

AAA Amphibians (byte 3 is a placeholder, always = A)
AB* Birds
  • P: Passerine (perching) Birds
  • N: Non-passerine Birds
AF* Fish (byte 3 is Class: A, B, C as shown below)
  • A: Lampreys and hagfish
  • B: Sharks and rays
  • C: Bony fishes
AMA Mammals (byte 3 is a placeholder, always = A)
ARA Reptiles (byte 3 is a placeholder, always = A)

Communities (bytes 1, 2):

CA Aquatic Inland Water Communities
CE Aquatic Estuarine Communities
CL Aquatic Palustrine Communities
CM Aquatic Marine Communities
CR Aquatic Riverine Communities
CT Terrestrial Communities

Invertebrate Animals (bytes 1, 2, 3, 4, 5):

IA*** Annelids (worms; followed by three-letter acronym of Class name):
  • HIR: Hirudinea
  • OLI: Oligochaeta
  • POL: Polychaeta
IC*** Crustaceans (followed by three-letter acronym of Subclass name):
  • BRA: Branchiopoda (fairy shrimp)
  • CEP: Cephalocarida
  • COP: Copepoda
  • OST: Ostracoda
  • CIR: Cirripedia (barnacles)
  • MAL: Malacostraca (crabs, lobsters, shrimp, krill, amphipods, etc.)
ID*** Cnidarians (Coelenterata; followed by three-letter acronym of Class name):
  • ANT: Anthozoa
  • HYD: Hydrozoa
  • SCY: Scyphozoa
IDCTE Ctenophores (comb jellies)
IEECH Echinoderms (starfish, sea urchins, sand dollars, sea cucumbers, etc.)
IGLOP Lophophorates
II*** Insects (followed by three-letter acronym of Order name):
  • ANO, DER, EMB, HEM, MAL, PSO, THY, ZOR (true bugs)
  • CLL, EPH, PRO, THS (mayflies)
  • COL, NEU (beetles)
  • DIP (flies)
  • HOM (aphids)
  • HYM (bees, wasps, ants)
  • ISO, PLE (stoneflies)
  • LEP, MEC, STR (butterflies & moths)
  • ODO (dragonflies)
  • ORT (grasshoppers)
  • SIP (fleas)
IK*** Aschelminths (followed by three-letter acronym of Phylum name):
  • ACA: Acanthocephala
  • GAS: Gastrotricha
  • KIN: Kinorhyncha
  • NEM: Nematoda
IL*** Chelicerates (followed by three-letter acronym of Class name):
  • ARA: Arachnida (spiders)
  • MER: Merostomata
IM*** Mollusks (followed by three-letter acronym of Class name):
  • BIV: Bivalvia
  • CEP: Cephalopoda
  • GAS: Gastropoda
  • MON: Monoplacophora
  • POL: Polyplacophora
  • SCA: Scaphopoda
INNEM Nemerteans (ribbon worms)
IP*** Platyhelminthes (flatworms; followed by three-letter acronym of Class name):
  • CES: Cestoda
  • TRE: Trematoda
  • TUR: Turbellaria
IRPRT Lesser Protosomes
ITUNI Uniramian arthropods (except insects)
IWDEU Lesser Deuterosomes
IZPLA Placozoa
IZPRT Protozoa
IZSPN Porifera (sponges)

Non-vascular plants and other kingdoms (bytes 1, 2, 3, 4, 5):

NAALG Algae
NB*** Bryophytes (followed by three-letter acronym of Order name):
  • ANT: Anthoceratae (hornworts)
  • HEP: Hepaticae (liverworts)
  • MUS: Musci (mosses)
NFFUN Fungi
NL*** Lichens (followed by three-letter acronym of Order name):
  • LEC: Lecanorales (for example)

Vascular Plants (bytes 3, 4, 5 are acronyms of Family name.  Example: PDAST = Asteraceae, the Sunflower Family):

PD Dicots (broadleaved plants)
PG Gymnosperms (conifers and others)
PM Monocots (grasses, palms, and others)
PP Pteridophytes (ferns)

Bytes 4 through 10 are sequential codes as assigned in TNC-designated publications, contact NatureServe for specifics:

Byte 4 Taxonomic Order
Byte 5 Taxonomic Family
Bytes 6 & 7 Taxonomic Genus
Bytes 8 & 9 Taxonomic Species
Byte 10 Taxonomic Subspecies

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Elevation   (Occurrence field)

The general Elevation, in feet, where the element occurrence is located.  This field remains blank for many "non-specific" occurrences when the exact placement of the centrum is somewhat arbitrary.

 

EOndx   (Occurrence field)

The Element Occurrence Index (EOndx) is a unique integer key for each element occurrence (EO) record.

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Federal Listing Status   (Element field)

The United States legal status under the Federal Endangered Species Act (ESA).

Listing Status Description
Endangered The classification provided to an animal or plant in danger of extinction within the foreseeable future throughout all or a significant portion of its range.
Threatened The classification provided to an animal or plant which is likely to become an Endangered species within the foreseeable future throughout all or a significant portion of its range.
Proposed Endangered The classification provided to an animal or plant that is proposed for federal listing as Endangered in the Federal Register under Section 4 of the Endangered Species Act.
Proposed Threatened The classification provided to an animal or plant that is proposed for federal listing as Threatened in the Federal Register under Section 4 of the Endangered Species Act.
Candidate The classification provided to an animal or plant that has been studied by the United States Fish and Wildlife Service, and the Service has concluded that it should be proposed for addition to the Federal Endangered and Threatened species list.
None The plant or animal has no federal status.
Delisted The plant or animal was previously listed as Endangered or Threatened, but is no longer listed on the Federal Endangered and Threatened species list.

(Please see the Federal Register for the current legal definitions of Federal status.)

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General Comments   (Occurrence field)

General Comments about an element occurrence that didn't fit physically or topically in the other comments fields.

 

General Habitat   (Element field)

General Habitat information for a particular element.

 

Global Rank   (Element field)

The Global Rank is a reflection of the overall condition and imperilment of an element throughout its global range.  Both the Global and State ranks represent a letter+number score that reflects a combination of Rarity, Threat and Trend factors, with weighting being heaviest on the rarity factors.  The Global Ranks are assigned by NatureServe in coordination with the appropriate state program(s) where the element occurs.

Global Rank Definition
GX Presumed Extinct (species) — Not located despite intensive searches and virtually no likelihood of rediscovery.

Extinct (ecological communities and systems) — Eliminated throughout its range, with no restoration potential due to extinction of dominant or characteristic taxa and/or elimination of the sites and ecological processes on which the type depends.
GH Possibly Extinct — Known from only historical occurrences but still some hope of rediscovery.  There is evidence that the species may be extinct or the ecosystem may be eliminated throughout its range, but not enough to state this with certainty.  Examples of such evidence include 1) that a species has not been documented in approximately 20–40 years despite some searching or some evidence of significant habitat loss or degradation; 2) that a species or ecosystem has been searched for unsuccessfully, but not thoroughly enough to presume that it is extinct or eliminated throughout its range.
G1 Critically Imperiled — At very high risk of extinction due to extreme rarity (often 5 or fewer populations), very steep declines, or other factors.
G2 Imperiled — At high risk of extinction due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors.
G3 Vulnerable — At moderate risk of extinction or elimination due to a restricted range, relatively few populations (often 80 or fewer), recent and widespread declines, or other factors.
G4 Apparently Secure — Uncommon but not rare; some cause for long-term concern due to declines or other factors.
G5 Secure — Common; widespread and abundant.
GNR Unranked — Global rank not yet assessed.
GU Unrankable — Currently unrankable due to a lack of information or due to substantially conflicting information about status or trends.
G#G# Range Rank — A numeric range rank (e.g., G2G3) is used to indicate the range of uncertainty about the exact status of a taxon or community.
G#T# Infraspecific Taxon — The status of infraspecific taxa (subspecies or varieties) are indicated by a "T-rank" following the species' Global Rank.  Rules for assigning T-ranks follow the same principles as those for Global Ranks.  However, a T-rank cannot imply the subspecies or variety is more abundant than the species.  With the subspecies, the G-rank reflects the condition of the entire species, whereas the T-rank reflects the global situation of just the subspecies or variety.
? Qualifier: Inexact Numeric Rank — A question mark represents a rank qualifier, denoting an inexact or uncertain numeric rank.
Q Qualifier: Questionable Taxonomy — The distinctiveness of this entity as a taxon or community at the current level is questionable; resolution of this uncertainty may result in change from a species to a subspecies or hybrid, or inclusion of this taxon or type in another taxon or type, with the resulting taxon having a lower-priority (numerically higher) conservation status rank.
C Qualifier: Captive or Cultivated Only — The taxon or community at present is presumed or possibly extinct or eliminated in the wild across its entire native range but is extant in cultivation, in captivity, as a naturalized population (or populations) outside its native range, or as a reintroduced population or ecosystem restoration, not yet established.

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Habitats   (Element field)

The Habitats that are associated with a particular element.

 

Last Updated Date   (Occurrence field)

The Last Updated Date is when the text or spatial information for this element occurrence (EO) was last updated.

 

Latitude   (Occurrence field)

The Latitude of the element occurrence centrum.  Note that, if the spatial feature consists of multiple polygons, the intersection point of the latitude/longitude coordinates may not represent the geographic center of all the polygons since that point may not fall within any of those polygons.  In that case, the coordinates are adjusted by staff to fall within one of the occurrence polygons near the geographic center of all of them.

 

Location   (Occurrence field)

A description of the Location of the element occurrence.

 

Longitude   (Occurrence field)

The Longitude of the element occurrence centrum.  Note that, if the spatial feature consists of multiple polygons, the intersection point of the latitude/longitude coordinates may not represent the geographic center of all the polygons since that point may not fall within any of those polygons.  In that case, the coordinates are adjusted by staff to fall within one of the occurrence polygons near the geographic center of all of them.

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Mapndx   (Occurrence field)

The Map Index (Mapndx) uniquely identifies a geographic location.  This location may consist of a multi-parted polygon in a single complex, all found within the defined separation distance for that element.  More than one element occurrence may be at a given Mapndx, creating a situation known as a "multiple."  For this reason, the Mapndx is NOT unique for each element occurrence record; the Element Occurrence Index uniquely identifies each of these records.

 

Micro Habitat   (Element field)

Where known, a description of the Micro-habitat with which the element is associated.

 

Occurrence Number   (Occurrence field)

The Occurrence Number uniquely identifies a particular instance of an element.  Occurrence numbers are assigned sequentially as element occurrences are mapped.  The first instance mapped for an element is number 1; the eighteenth location is number 18, etc.  There may be gaps in the number sequence as occurrences are combined.  Taken together, Element Code and Occurrence Number uniquely identify an element occurrence.

 

Occurrence Rank   (Occurrence field)

An element's Occurrence Rank is a ranking of the quality of the habitat and the condition of the population at that location.  The possible values for Occurrence Rank are:

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Occurrence Type   (Occurrence field)

The Occurrence Type indicates the origin of the element occurrence.  The possible values for Occurrence Type are:

 

Other Status   (Element field)

The Other Status field provides additional status listings for an element, including the Department of Fish and Wildlife's Fully Protected and Species of Special Concern designations.

Organization Status Listing
AFS - American Fisheries Society
EN – Endangered
TH – Threatened
VU – Vulnerable
BLM - Bureau of Land Management S – Sensitive
CDF - California Department of Forestry & Fire Protection S – Sensitive
CDFW - California Department of Fish & Wildlife
FP - Fully Protected
SSC - Species of Special Concern
WL - Watch List
IUCN - International Union for the Conservation of Nature
CD - Conservation Dependent
CR - Critically Endangered
DD - Data Deficient
EN - Endangered
EW - Extinct in the Wild
EX – Extinct
LC - Least Concern
NE - Not Evaluated
NT - Near Threatened
VU - Vulnerable
MMC - Marine Mammal Commission SSC - Species of Special Concern
NABCI - North American Bird Conservation Initiative
RWL - Red Watch List
YWL - Yellow Watch List
NMFS - National Marine Fisheries Service SC - Species of Concern
SB - Seed Banked
BerrySB - Berry Seed Bank
CRES - San Diego Zoo CRES Native Gene Seed Bank
KewBG - Kew Royal Botanic Gardens
RSABG - Rancho Santa Ana Botanic Garden
SBBG - Santa Barbara Botanic Garden
UCBBG - UC Berkeley Botanical Garden
USDA - US Dept of Agriculture
USFS - United States Forest Service S – Sensitive
USFWS - United States Fish & Wildlife Service BCC - Birds of Conservation Concern
WBWG - Western Bat Working Group
H - High Priority
MH - Medium-High Priority
M - Medium Priority
LM - Low-Medium Priority
XERCES - Xerces Society
CI - Critically Imperiled
IM – Imperiled
VU - Vulnerable
DD - Data Deficient

 

Owner/Manager   (Occurrence field)

The type of ownership or management of the site: private, public (U.S. Forest Service, Bureau of Land Management, etc.), conservation organization, etc., if known.  A site may have multiple owners and/or managers

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PLSS   (Occurrence field)

The Public Land Survey System (PLSS) is a way of subdividing and describing land in the United States.  The PLSS consists of a series of separate surveys, which begin at an initial point.  The north-south line that runs through the initial point is a true meridian and is called the Principal Meridian.  The east-west line that runs through the initial point is called a baseline.  This system typically divides land into 6-mile-square townships, which are further subdivided into 36 one-mile-square sections.  Sections can be further subdivided into quarter sections.  Townships are surveyed north, south, east, and west from the initial point formed by the intersection of the meridian and the baseline.  Each township is identified with a township and range designation.  Township designations indicate the location north or south of the baseline, and range designations indicate the location east or west of the meridian.

For element occurrences, the PLSS coordinate indicates where the center of the occurrence is most likely located.  The meridian is indicated in parentheses, and is either "M," "H," or "S."  These letters correspond to the Mt. Diablo, Humboldt, or San Bernardino meridians, respectively.

 

Presence   (Occurrence field)

Presence refers to the condition of the occurrence at the site when it was last observed.  The possible values for Presence are:

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Quad   (Occurrence field)

The USGS 7.5 minute quadrangle (Quad) map, or maps, containing the element occurrence.  The USGS quad code consists of one degree blocks sub-divided into sixty-four 7.5 minute maps.  The one degree block is referenced by the latitude and longitude of its southeast corner (e.g., 38121).  Individual maps within the block are referenced by an alpha-numeric code.  This code originates at the same southeast corner as the one degree block and runs numerically east to west, and alphabetically south to north.  This creates a grid allowing maps to be coded by the intersection of these axes (e.g., B5).  A complete map code would be 38121B5. The CNDDB quad code converts this value to an integer by replacing the alpha character with a numeric equivalent (A = 1, B = 2, C = 3, D = 4, E = 5, F = 6, G = 7, H = 8).

 

Returned Occurrences   (Element field)

The number of occurrences for a particular element returned for the current query.

 

Scientific Name   (Element field)

The Scientific (Latin) Name of a plant or animal or the name of a Natural Community recognized at the state level.

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State Listing Status   (Element field)

The State of California legal status.

Listing Status Description
Endangered The classification provided to a native species or subspecies of a bird, mammal, fish, amphibian, reptile, or plant which is in serious danger of becoming extinct throughout all, or a significant portion, of its range due to one or more causes, including loss of habitat, change in habitat, overexploitation, predation, competition, or disease.
Threatened The classification provided to a native species or subspecies of a bird, mammal, fish, amphibian, reptile, or plant that, although not presently threatened with extinction, is likely to become an endangered species in the foreseeable future in the absence of special protection and management efforts.
Rare The classification provided to a native plant species, subspecies, or variety when, although not presently threatened with extinction, it is in such small numbers throughout its range that it may become endangered if its present environment worsens.  This designation stems from the Native Plant Protection Act of 1977.
None The plant or animal has no state status.
Delisted The plant or animal was previously listed as Endangered, Threatened or Rare but is no longer listed by the State of California.
Candidate Endangered The classification provided to a native species or subspecies of a bird, mammal, fish, amphibian, reptile, or plant that the Fish and Game Commission has formally noticed as being under review by the Department of Fish and Wildlife for addition to the list of endangered species, or a species for which the commission has published a notice of proposed regulation to add the species to the list of endangered species.
Candidate Threatened The classification provided to a native species or subspecies of a bird, mammal, fish, amphibian, reptile, or plant that the Fish and Game Commission has formally noticed as being under review by the Department of Fish and Wildlife for addition to the list of threatened species, or a species for which the commission has published a notice of proposed regulation to add the species to the list of threatened species.

(See Fish and Game code, sections 1901, 2062, 2067, and 2068 for legal definitions of California State status.)

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State Rank   (Element field)

The State Rank is a reflection of the condition and imperilment of an element throughout its range within the state.  Both the Global and State ranks represent a letter+number score that reflects a combination of Rarity, Threat and Trend factors, weighted more heavily on the rarity factors.  The State Ranks are assigned by California heritage biologists using standard natural heritage methodology.

State Rank Description
SX Presumed Extirpated — Species or community is believed to be extirpated from the state.  Not located despite intensive searches of historical sites and other appropriate habitat, and virtually no likelihood that it will be rediscovered.
SH Possibly Extirpated (Historical) — Species or community occurred historically in the state, and there is some possibility that it may be rediscovered. All sites are historical; the element has not been seen for at least 20 years, but suitable habitat still exists.
S1 Critically Imperiled — Critically imperiled in the state because of extreme rarity (often 5 or fewer occurrences) or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state.
S2 Imperiled — Imperiled in the state because of rarity due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors making it very vulnerable to extirpation from the nation or state.
S3 Vulnerable — Vulnerable in the state due to a restricted range, relatively few populations (often 80 or fewer), recent and widespread declines, or other factors making it vulnerable to extirpation.
S4 Apparently Secure — Uncommon but not rare; some cause for long-term concern due to declines or other factors.
S5 Secure — Common, widespread, and abundant in the state.
SNR Unranked — State conservation status not yet assessed.
SU Unrankable — Currently unrankable due to a lack of information or due to substantially conflicting information about status or trends.
S#S# Range Rank — A numeric range rank (e.g., S2S3) is used to indicate any range of uncertainty about the status of the species or community.
? Qualifier: Inexact or Uncertain — A question mark represents a rank qualifier, denoting an inexact or uncertain numeric rank.

Note: Older ranks, which need to be updated, may still contain a decimal "threat" rank of .1, .2, or .3, where .1 indicates very threatened status, .2 indicates moderate threat, and .3 indicates few or no current known threats.

 

Suppressed (Sensitive)   (Occurrence field)

When an element occurrence is labeled "Suppressed," all location-specific data are restricted/suppressed.  Data are considered "Sensitive" and their location information is consequently suppressed by the CNDDB for a number of possible reasons, including:

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Taxonomic Group   (Element field)

The general Taxonomic Group that an element falls within.  The following groups are currently used by the CNDDB:

Animals Invertebrates Arachnids
Crustaceans
Insects
Mollusks
Vertebrates Amphibians
Birds
Fish
Mammals
Reptiles
Community Aquatic Estuarine
Inland Waters
Marine
Palustrine
Riverine
Terrestrial Alpine
Dune
Forest
Herbaceous
Marsh
Riparian
Scrub
Woodland
Plants Nonvascular Bryophytes
Lichens
Vascular Dicots
Ferns
Gymnosperms
Monocots
Fungi

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Threat Comments   (Occurrence field)

Comments about threats to this element at this location.

 

Threat List   (Occurrence field)

A list of specific threats to this element at this location.  These threats receive a code which makes them easier to categorize and search in CNDDB programs such as RareFind.  Currently recognized threats are:

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Total Occurrences   (Element field)

The current total number of occurrences for a particular element.  Note that, depending upon how it was constructed, a RareFind query might not return all occurrences for an element.

 

Trend   (Occurrence field)

Trend is a general measure of the population at this location.  The possible values for Trend are:

 

UTM   (Occurrence field)

The Universal Transverse Mercator (UTM) coordinate system is a grid-based method of specifying locations on the surface of the Earth.  This system divides the surface of the Earth between 80°S and 84°N latitude into 60 zones, each 6° of longitude in width and centered over a meridian of longitude.  The point of origin of each UTM zone is the intersection of the equator and the zone's central meridian, with the central meridian of each zone set at 500,000 meters East.  Zone numbering increases in an easterly direction.

A UTM coordinate consists of the UTM zone, and the easting and northing coordinate pair.  The easting is the projected distance of the position eastward from the central meridian of the zone, while the northing is the projected distance of the point north from the equator.  Eastings and northings are measured in meters.

For element occurrences, the UTM coordinate indicates where the center of the occurrence is most likely located.

 


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