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NatureServe and our Network scientists document and map the locations of species and ecosystems using a standard set of methods. This allows us to identify the places that, if conserved and appropriately managed, can contribute to the species’ long-term survival. Intrepid scientists in the NatureServe Network have spent countless hours in the field, where they have collectively found, documented, and mapped over a million places that support rare and imperiled species and ecosystems.

Arrowleaf Balsamroot (Balsamorhiza sagittata) NatureServe Global Status: Secure (G5). Photo by Kari Cieszkiewicz, USFS.

Element Occurrences

In order to get the best information for conservation, NatureServe and our Network scientists use Element Occurrences to track populations of species. An Element Occurrence is an area of land and/or water in which a species or natural community is (or was) present. Element Occurrences therefore have practical value for supporting biodiversity. Because they are defined on the basis of biological information, Element Occurrences may cross jurisdictional boundaries.

Element Occurrence Data Standard

The Element Occurrence (EO) data standard is the product of a collaboration among NatureServe Network scientists to improve the consistency and accuracy of EO data throughout the Network. It sets out a standardized vocabulary and definitions and establishes guidelines for the collection and management of EO attribute data as well as their spatial representation on maps. The standards help ensure that locations defined as EOs have practical conservation value and that EO records can be compiled across jurisdictions to contribute to a rangewide picture of conservation status.


Knowledge of where species and communities exist on the ground and the viability of their populations or stands is essential for assessing risk of extirpation or extinction and for planning conservation actions. The EO data standard provides a common foundation on which zoologists, botanists, and ecologists can build discipline-specific guidance for surveying, assessing, and mapping locations of high-priority “elements of biodiversity.” It has been integrated into software tools used throughout the NatureServe Network in order to facilitate consistent data development.

Features & Benefits

The EO concept is the linchpin of the work of the NatureServe Network. EOs typically represent populations and ecosystems that, if conserved, can contribute to the survival or persistence of the element. EO methodology provides a consistent approach to data management, including defining, delineating, ranking, and mapping EOs. The EO Data Standard was developed to encourage a comprehensive and uniform approach to EO data management, helping ensure consistency and comparability of data among programs.

The data standard is the outcome of the EO Design Project that began in 1996 and involved experts in conservation biology and GIS. Following extensive review by Network personnel, the EO data standard was published in 2002. The recommendations in the data standard were incorporated into NatureServe’s Biotics 4 data management system, introduced to the Network in 2003. In 2010, a team of NatureServe Network staff refined and improved the part of the standard devoted to spatial feature development. The result is a set of changes based on recommendations from users of the methodology that are designed to streamline the spatial workflow. Biotics 5 incorporates these updates by automating several steps in the EO mapping process.

Topics addressed in the data standard include:


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Oregon Ensatina
Oregon Ensatina (Ensatina eschscholtzii oregonensis) NatureServe Global Status: Secure (G5). Photo by Natalie McNear.

Biodiversity Observation Data Standard

As pressures on biodiversity increase, there is an increasing need for rapid and more comprehensive biodiversity assessments and an increasing volume of observation data available from citizen science and other data collection efforts across the globe. To meet this need NatureServe developed a standard for collecting and compiling biodiversity observation data across the Network and from external sources.

The Biodiversity Observation Data Standard addresses two key objectives:

  1. It provides a comprehensive set of fields that are relevant to most Network programs and meet individual program needs for collection and management of observation data.
  2. It identifies subset of core biodiversity observation data fields that can be used to aggregate data in support of key Network-wide products:
  • Spatial biodiversity distribution products (including element occurrences, range maps, hexagon grid-observations, and habitat suitability models)
  • Conservation status assessments
  • Quality/condition assessments of at-risk species and ecosystems.

The Biodiversity Observation Data Standard contains a comprehensive list of 166 fields for use by Network programs to collect and manage biodiversity observation data. Fields that are directly equivalent to Darwin Core are noted. The Standard identifies the subset of fields required to create a basic observation, a larger subset that will support the generation of core network products and additional fields that are needed to import observation data from external sources.


The Biodiversity Observation Data Standard places NatureServe and the Network in a better position to place the most current, complete, and consistent biodiversity data into the hands of researchers and decision makers. It will facilitate the use of observations collected by sources such as GBIF and GeoBON, other partner organizations, as well as citizen scientist efforts like eBird, and iNaturalist. It will also standardize and leverage Network data by facilitating the creation of a wide range of products beyond that of Element Occurrences, including inputs to habitat suitability models, gridded occurrence or hotspot maps, and species and ecosystem conservation status and condition assessments.

Features & Benefits

The standard is designed to a) effectively manage observation data at the individual program level, b) support the key network products, and c) maximize compatibility with Darwin Core to aid the use of data from other sources. A series of apps, tools, and protocols based on the standard have been developed to facilitate the collection and aggregation of observation data and the creation of key products.

Photo by Sam Sheline.

Field Inventory

With thousands of rare plants, animals, and ecosystems to track, NatureServe and the Network have designed efficient survey programs to provide the critical information needed by decision-makers.

The NatureServe Network needs reliable field data for the many thousands of endangered species and ecosystems that comprise our natural world. Our information databank is continually expanding, as new threats emerge. NatureServe has developed consistent methods, databases, and tools for conducting biodiversity inventories to maximize the benefits derived from field survey data. Our methods rely on recent developments in remote sensing and geographic information systems (GIS), hand-held databases, and standardized field forms that greatly enhance methods to screen and inventory large landscapes for biodiversity features. Our carefully selected list of species and ecosystem targets ensures that we focus on the elements of biodiversity most in need of protection, management, or study.


Agencies, businesses, and organizations that seek to conserve or study biodiversity want to either avoid or minimize impacts to endangered species and ecosystems or to help maintain and restore them. To achieve their aims, they require up-to-date information on the locations and conditions of these elements. NatureServe and its member programs can provide accurate, up-to-date information, or are positioned to conduct needed surveys as quickly as possible. Our methods are designed to allow us to track and monitor species and ecosystems over time, in order to detect changes in locations, abundance and condition.

Features & Benefits

NatureServe's member programs—a hemisphere-wide Network of natural heritage programs and conservation data centers—conduct expert local biodiversity inventories and analyze the results within a national and international context. The 800-plus staff from across the Network include some of the most knowledgeable biologists and ecologists in their respective fields and are renowned as local and regional experts.

Each year, the programs conduct field surveys for rare plants and animals and other species of conservation concern and for exemplary and endangered ecosystems. Program staff perform viability assessments for species and populations and ecological integrity assessments for ecosystems. Inventory results dating back to the 1970s are tracked in sophisticated biodiversity databases. Places of special significance are targeted on a project-by-project basis. The results can be reported in a variety of forms-in database files, maps, GIS layers, and published papers. Our field survey information is recorded in state, provincial, and central databases and is available by request.

Natural heritage biologists discover hundreds of new populations of at-risk species annually, adding to our knowledge of our natural world. Often, natural heritage inventories can determine that a species is not as rare as previously thought, thus helping to guide effective allocation of scarce conservation resources. These field data can also be used to build and improve species distribution models, thereby leading to predictions of where new populations may be found.

NatureServe ecologists use a variety of sophisticated tools including remote sensing and geographic information systems (GIS), hand-held databases, and standardized field forms to classify, map and conduct field surveys on a wide variety of ecosystems. Detailed vegetation plot data are recorded that describe the component species, soils, hydrology and disturbance factors present on a site, and these data provide valuable information for ongoing improvements to ecosystem classification and mapping. These data are collected and stored in a variety of databases, and ultimately used to document the natural and historic range of variability of ecosystems, their integrity, and landscape patterns. Maps at the local, county, subnational, national and international levels are becoming increasingly available. With this information in hand, ecologists are better positioned to provide the critical data needed for conservation status and ecological integrity assessments, and contribute to conservation planning.