For
Plants
Plant distribution data in NatureServe Explorer are based on a variety of sources. With few exceptions, the state and province distribution records of species with conservation status information (i.e., subnational ranks) are based on information received from the respective natural heritage member program. For vascular plants, most other state and province records, especially for more common species, are based on distribution information shown in various prepublication drafts of the Synthesis of the North American Flora (Kartesz, 1999); some revisions to those records may be required to conform with the future versions of that publication. A small number of distribution records are added from other sources, such as the U.S. Fish and Wildlife Service, the Canadian Museum of Nature, and botanical literature reviewed by NatureServe botanists.
Vascular
Plant Reference:
Kartesz
JT. 1999. A synonymized checklist and atlas with
biological attributes for the vascular flora of
the United States, Canada, and Greenland. In:
Kartesz JT, Meacham CA. Synthesis of the North
American Flora, Version 1.0. Chapel Hill: North
Carolina Botanical Garden.
For
Vertebrates and Invertebrates
Animal distribution data in NatureServe Explorer are derived from many sources. For
vertebrates and certain well-studied groups of invertebrates, the primary sources are scientific literature, web sites, experts, and information from local data centers. Many of the same sources used for taxonomy and nomenclature are consulted for distribution information. In turn, much of the published information is based on museum specimen records and, especially for birds, reliably documented observation records. Review of the available literature and other sources is done by NatureServe zoologists and by other experts contracted to develop this information, who supplement their literature research with personal knowledge. Over time, state and province distribution lists are refined as local data centers obtain new records for species not previously recognized in their jurisdictions and transfer this new information to the NatureServe's central databases during the annual data exchange process. For invertebrates in less well-studied groups, the state and province data in the central databases come from local natural heritage zoologists who derive their knowledge from the sources mentioned above, especially local experts and museum collections.
County and Watershed Distribution (based on available natural heritage records)
County and watershed distribution data are available for plants and animals listed under the U.S. Endangered Species Act, including those already listed as threatened or endangered and those that are candidates or have been proposed for listing. In addition, distribution data are available for species tracked by the natural heritage network with an emphasis on those species with a NatureServe global conservation status of critically imperiled (G1 or T1) and imperiled (G2 or T2). Data on ecological communities are not currently available at these scales.
See below
for important caveats about the completeness of these
county and watershed distributions.
The county and watershed distribution data based on natural heritage records presented on this site include all U.S. states except NH and MA. In addition, county and watershed data based on natural heritage records for animals of AK and for most animals of WA are not available. The data are based on Element Occurrence (EO) records, precise locality data that are developed and maintained by individual state natural heritage programs¹. The focus of these programs is on collecting data for imperiled species, therefore data is most complete for plants and animals that are imperiled (G1 or G2) and incomplete or non-existent for plants and animals with a NatureServe global conservation status of at-risk or apparently or demonstrably secure (G3 or T3, G4 or T4, G5 or T5). Data for selected species may include information based on historical records. If your search returns no records, then the participating programs have no data available at this website. However, natural heritage biologists have extensive knowledge of plants and animals within their respective jurisdictions; for additional information please contact the appropriate natural heritage program or NatureServe.
In addition to watershed distribution data based on natural heritage records, this site presents maps based on a variety of information sources. See: U.S. Distribution by Watershed for more information. We are always looking to improve the overall quality of our databases. If you have information on a current occurrence of a G1/T1 or G2/T2 ranked plant or animal for a particular county or watershed not indicated on this report, please contact the appropriate Natural Heritage Program (http://www.natureserve.org/visitLocal/index.jsp).
Currentness
The
dates these data were acquired vary for each area
participating; they are:
Participating Jurisdiction |
Date Data Acquired |
Alabama |
April 2006 |
Alaska |
December 2005 |
Arizona |
December 2005 |
Arkansas |
August 2004 |
| California |
April 2006 |
Colorado |
December 2005 |
Connecticut |
June 2006 |
Delaware |
May 2004 |
Florida |
April 2006 |
Georgia |
January 2007 |
Hawaii |
November 2005 |
Idaho |
January 2006 |
Illinois |
May 2006 |
Indiana |
October 2007 |
Iowa |
September 2006 |
Kansas |
May 2005 |
Kentucky |
September 2006 |
| Louisiana |
June 2006 |
Maine |
August 2007 |
Maryland |
September 2006 |
Massachusetts |
Data not available |
Michigan |
May 2006 |
Minnesota |
July 2007 |
Mississippi |
September 2006 |
Missouri |
September 2006 |
Montana |
July 2007 |
Navajo Nation |
October 2006 |
Nebraska |
June 2006 |
| Nevada |
February 2006 |
New Hampshire |
Data not available |
New Jersey |
July 2004 |
New Mexico |
May 2006 |
New York |
June 2006 |
North Carolina |
September 2005 |
North Dakota |
May 2006 |
Ohio |
June 2006 |
Oklahoma |
December 2005 |
Oregon |
January 2006 |
Pennsylvania |
September 2006 |
Rhode Island |
June 2006 |
South Carolina |
August 2007 |
South Dakota |
August 2007 |
Tennessee |
December 2006 |
Texas |
March 2006 |
Utah |
May 2006 |
Vermont |
November 2006 |
Virginia |
August 2007 |
Washington |
March 2006 |
West Virginia |
December 2006 |
Wisconsin |
June 2006 |
Wyoming |
September 2007 |
U.S. Distribution by Watershed (based on multiple information sources)
For most native, freshwater U.S. fishes, watershed distribution maps are available. These maps are based on a variety of information sources and are generally more complete than what is available via the NatureServe Explorer watershed search which currently searches based on natural heritage element occurrence records. The distribution data presented here are an initial attempt to present the complete current and historic distributions by small watershed (USGS 8-digit cataloging unit) of all native freshwater fishes of the United States, exclusive of Alaska and Hawaii. These data derive in part from precise location data (element occurrences) compiled by state natural heritage programs for 307 vulnerable or imperiled fish species. The natural heritage-derived locational data were supplemented with information from the scientific literature and from species experts to compile the most complete distributional information possible for these species at the level of USGS 8-digit cataloging unit. Analyses of these data were first presented in the report Rivers
of Life: Critical Watersheds for Protecting Freshwater
Biodiversity (1998). The analyses were also
published in amended form in Precious
Heritage: The Status of Biodiversity in the United
States. Subsequently, funding from the Regina Bauer Frankenberg Foundation for Animal Welfare and from The Nature Conservancy allowed us to expand the database to include all native freshwater fishes of the conterminous United States and to include historic-only as well as current watersheds of occurrence. The data were thus compiled over a period of several years (1997 to 2003).
These data are dynamic with new records frequently being added and old records being revised as new information is received. As a result, the information on this website should not be considered a definitive statement on the presence or absence of freshwater fishes in any given watershed, nor should be used as a substitute for on-site surveys required for environmental assessments.
In any data set such as this there will be errors of omission as well as errors of commission. We ask users of these data to let us know about such errors so that the data can be improved over time for the future benefit of all users. Comments can be submitted through the Contact Us button above or by email to Bruce Young, Director, Species Science. Please cite the data source for any omissions or changes in status (e.g., current to historic-only). We hope that these data will be a useful tool for aquatic research and analyses and for conservation planning.
¹ An element occurrence is NatureServe's basic unit of record for documenting and delimiting the presence and extent of a species or natural community on the landscape. EOs are defined as an area of land and/or water where a species or ecological community is, or was, present, and which has practical conservation value. Element occurrences for species commonly reflect populations or subpopulations. (For additional details about element occurrences, see natural heritage methodology.)
Distributions for Ecological Communities
National and Subnational Distribution
U.S. state, Canadian province and ecoregional distribution information is an inherent part of the development of both parts of the International Ecological Classification Standard: the International Vegetation Classification, and the International Terrestrial Ecological System Classification. NatureServe ecology staff and other experts review distributional data and assign communities to additional states, provinces, and ecoregions based on their knowledge of the local flora, analyses of vegetation data, and consideration of more qualitative information on vegetation patterns. However, absence of a state, province, or ecoregion from the distributional data cannot be interpreted as a definitive statement that the community does not occur there.
Ecoregions
The Nature Conservancy Ecoregions
The Nature Conservancy (TNC) developed a map of "ecoregions" to organize its conservation prioritization work. TNC first delineated ecoregions for the United States in the late 1990s (adapted from Bailey et al.1994), and has now delineated ecoregions for all of North America. For the rest of the world, TNC has adopted World Wildlife Fund (WWF) ecoregions. For more information, see "Conservation By Design". TNC is currently in the process of delineating marine ecoregions for the Western Hemishpere, but NatureServe has not currently attributed any ecological units to the marine ecoregions.
For the United States, plant associations, vegetation alliances and ecological systems have all been attributed to TNC's ecoregions by TNC and NatureServe ecology staff. These data are reviewed and refined continually as vegetation mapping and conservation planning efforts proceed. For Latin America (including Mexico) and the Caribbean, ecological systems have been attributed to the WWF ecoregions, as adopted by TNC. These data will be available in the future on InfoNatura.
United States Forest Service Ecoregions
The U.S.D.A. Forest Service has developed a hierarchical framework, the National Hierarchical Framework of Ecological Units (as described by Cleland et al. 1997), which provides a systematic method for classifying and mapping areas of the earth based on co-occurring ecological factors at different geographic scales. NatureServe has attributed ecological communities in the U.S. to three of these ecoregion levels: Province, Section, and Subsection, with varying degrees of comprehensiveness across the country.
All western* U.S. plant associations and alliances are comprehensively attributed to Sections using Bailey et al. (1994), except in the interior Pacific northwest where the Section boundaries used are those developed by the U.S. Forest Service during the Interior Columbia Basin Ecosystem Management Project. Eastern* U.S. alliances and associations are attributed to Sections and Subsections using Keys et al. (1995): the data are comprehensive for alliances and on a more case-by-case basis for associations, with generally greater completeness for more globally rare associations. This map shows the combined Bailey et al. (1994) and Keys et al. (1995) NatureServe used, as well as the Section boundaries used in the interior Pacific Northwest.
For Ecological Systems, western U.S. systems have been attributed to the USFS Ecomap regions as described by Cleland et al. (2005). The eastern U.S. ecological systems will be attributed during late 2006 and 2007.
*Keys et al. (1995) provide the spatial framework and labeling of the USFS Ecoregional units for the area east of the "dry line." This generally corresponds to 97 degrees West longitude (or roughly just west of a line extending through Fargo, North Dakota, south through Corpus Christi, Texas), and includes Divisions 210, M210, 220, M220, 230, M230, 250 of the Humid Temperate Domain (200) and all of the Humid Tropical Domain (400). For areas west of the dry line, Bailey et al. (1994) provide the spatial framework for Divisions 240, M240, 260, M260 of the Humid Temperate Domain (200) of the west coast of the United States and all of the Dry Domain (300).
Bailey, R. G., P. E. Avers, T. King, and W. H. McNab, editors. 1994. Ecoregions and subregions of the United States (map). U.S. Geological Survey, Washington, DC. Scale 1:7,500,000 colored. Accompanied by a supplementary table of map unit descriptions compiled and edited by W. H. McNab and R. G. Bailey. Prepared for the USDA Forest Service.
Keys, J. E., Jr., C. A. Carpenter, S. L. Hooks, F. G. Koenig, W. H. McNab, W. E. Russell, and M-L. Smith. 1995. Ecological units of the eastern United States - first approximation (map and booklet of map unit tables). Presentation scale 1:3,500,000, colored. USDA Forest Service, Atlanta, GA.
Cleland, D. T., J.A. Freeouf, J. E. Keys, G. J. Nowacki, C. A. Carpenter, and W. H. McNab. 2005. Ecological subregions: Sections and subsections for the conterminous United States. Presentation scale 1:3,500,000, colored. USDA Forest Service, Washington, DC. Also available on CD-ROM consisting of GIS coverage in ArcINFO format.
MRLC - NLCD Map Zones
The Multi-Resolution Land Characteristics (MRLC) Consortium is a group of federal agencies who first joined together in 1993 to purchase Landsat 5 imagery for the conterminous U.S. and to develop a land cover dataset called the National Land Cover Dataset. In 1999, a second-generation MRLC consortium was formed to purchase three dates of Landsat 7 imagery for the entire United States (MRLC 2001) and to coordinate the production of a comprehensive land cover database for the nation called the National Land Cover Database (NLCD 2001). “Mapping zones” were developed for use by consortium members and any other partners, as described by Homer et al. (No date).
Under contract to the Interagency LANDFIRE project, NatureServe ecology staff have attributed Ecological Systems to MRLC Map Zones in the coterminous western U.S. from New Mexico north to Montana and west. These distributional data are being continually revised as review comments are provided to NatureServe by LANDFIRE partners and other partners. For the eastern U.S., ecological systems will be attributed to map zones during the remainder of 2006 and 2007.
Ecological Divisions
Ecological Divisions are sub-continental landscapes reflecting both climate and biogeographic history. Continent-scaled climatic variation, reflecting variable humidity and seasonality (e.g. Mediterranean vs. dry continental vs. humid oceanic) are reflected in these units, as are broad patterns in phytogeography (e.g. Takhtajan 1986. The division lines were modified by using ecoregions established by The Nature Conservancy and World Wildlife Fund throughout the Western Hemisphere. All ecological systems are attributed to one or more ecological divisions, and the names of the systems include the divisional ‘center of distribution’ as detailed in Comer et al. (2003).
Takhtajan, A. 1986. Floristic Regions of the World. Transl. by T.J. Crovello and ed. by A. Cronquist. University of California Press, Berkeley.