What is Gap Analysis?What is Gap Analysis?Gap analysis is a scientific method for identifying the degree to which native animal species and natural communities are represented in our present-day mix of conservation lands. Those species and communities not adequately represented in the existing network of conservation lands constitute conservation "gaps." The purpose of the Gap Analysis Program (GAP) is to provide broad geographic information on the status of ordinary species (those not threatened with extinction or naturally rare) and their habitats in order to provide land managers, planners, scientists, and policy makers with the information they need to make better-informed decisions.
To achieve this, GAP is the first state- and national-level effort to complete the following:
Vegetation is mapped from satellite imagery and other records using the National Vegetation Classification System (FGDC 1996). Native animal species ranges are mapped by using museum and agency specimen collection records in conjunction with known general ranges and the animal's affiliation with the previously mapped vegetation types and other physical characteristics. These data are combined and displayed with a computerized geographic information system (GIS) at a cartographic scale of 1:100,000. Maps of vegetation types, individual species, or selected suites of species (depending on one's interest) are overlain on maps of land ownership and land management, showing where land-based conservation efforts can be focused to achieve the conservation of selected elements of biodiversity most efficiently, preventing both conservation crises and land-use surprises.
The Gap Analysis Program is sponsored and coordinated by the Biological Resources Division of the U.S. Geological Survey. Additional support at the national level has been provided by the Department of Defense and the Environmental Protection Agency. The program has a close working relationship with the National Mapping Division of the U.S. Geological Survey and with The Nature Conservancy.
Mapping and analysis is conducted by GAP projects within each state. Additional analyses are conducted for large multi state regions in partnership with state governments, federal agencies and other cooperators. Presently, GAP is made up of over 445 contributing organizations in 44 states. Contributors include business, universities, state and federal agencies, tribes, and non government organizations.
Because GAP provides a standardized method and format, the data can be edge-matched with adjacent states as the state projects are completed. The importance of having data which is consistent across state boundaries is in revealing, for the first time, actual patterns of biodiversity at scales relevant to both the magnitude of present-day changes and the multiple levels of biological organization - from species and natural communities to large landscapes.
One result is the generation of large amounts of information on land cover and zoological geography, and the demand for these data from all sectors is strong. Initial digital products, which are already available for the eleven Western states, Arkansas, Connecticut, Massachusetts, and Rhode Island, are being used for many different purposes by businesses, county planners, state agencies, schools, research institutions, nonprofit organizations, and federal agencies.
These data are disseminated by the state projects and over the Internet World Wide Web as well as in professional journals. Publication and distribution of the data on read-only-memory compact disks (CD-ROMs) is being developed.
Last Modified August 13, 1997.