Talk:Gap analysis (conservation)

Gap Analysis Program (GAP)
''This is my first Wikipedia entry, but here's an entry for the US National Gap Analysis Program (GAP). Please discuss and add to and correct as needed as part of the new Gap analysis (wildlife conservation) page.''

Gap Analysis is a GIScience application that has become a major tool in conservation planning since the 1980s. The original methods (Scott et al. 1993, Jennings 2000) include: mapping land cover type (usually vegetation); modeling species distributions based on predicted habitat suitability and subsequent field verification; and determining land stewardship and management status. ‘Gaps’ in the conservation network occur where areas of high species diversity or rare ecosystem type are not well-represented within protected areas.

1 U.S. National Gap Analysis Program (GAP)

The gap analysis methodology was formalized in 1987 by the USGS National Gap Analysis Program (GAP), providing a scientific, spatial analysis of the potential effects of habitat fragmentation on species viability. By 2003, the National GAP, a collaboration of hundreds multiple federal and state government agencies, universities, non-profit organizations, conservation groups, tribes, and businesses, had systematically analyzed the conservation networks of each of 48 conterminous United States. The stated goal of the National GAP is “keeping common species common” because it is assumed that protecting species is both easier and less expensive before they are threatened with extinction. The resulting extensive scientific dataset of land management/ownership, vegetation cover and terrestrial vertebrate distribution is mapped at the landscape scale (1:100,000), which permits regional analysis beyond state boundaries and has resulted in applications of gap analysis beyond the scope of the National GAP. Maps and data are available for free download at the USGS/NBII website:.

2 Critiques and Limitations of Gap Analysis

2.1 Threat Indicators, Scale Dependence & the ‘Modifiable Areal Unit Problem’

Indicators of human threats, such as population growth, land use, and road density have been proposed to enhance gap analysis and further prioritize which ‘gaps’ are most immediately threatened. However, because species responses to threats vary, gap analysis can only portray potential threats. Indicators of conservation value, such as species richness, have no inherent spatial scale. Thus, the optimal scale range for the minimum mapping unit (MMU) is determined on a case-by-case basis, compromising scientific credibility with data availability and cost effectiveness. Scale dependence of the MMU as a variant of the ‘Modifiable Areal Unit Problem’, or MAUP (Stoms 1994). The larger the MMU, the more species it will contain, either over-generalizing species richness by using large units or increasing statistical uncertainty for habitat distributions by using small units. Scale dependence introduces statistical error in spatial analysis.

2.2 Mapping Uncertainty

Predicted species habitat distributions in GAP data contain numerous errors of commission (attributing presence where a species is absent) and errors of omission (attributing absence where a species is present) resulting in large composite error when map layers are combined. Despite this fact, species distribution maps produced by gap analysis rarely incorporate error into the visual representation. In gap analysis applications, it can result in dramatically different conservation recommendations (Flather et al 1997). In addition, residual multiscale sampling effects can be identified using a statistical covariation measure, such as sensitivity analysis.

2.3 The ‘shifting baseline syndrome’

The baseline for all National GAP projects is determined by the satellite data used to determine the vegetation cover that predicts species habitat distribution, which already includes a large percentage of anthropogenic land uses. First, because historic species distribution is not known, gap analysis results are a mere fraction of any species original habitat. Also, the static nature of gap analysis currently is not able to show the dynamic response capacity of species to change or species viability over time (Jennings 2000). Shifting baselines require that gap analysis incorporates a case-by-case consideration of management goals and definitions of conservation success.

Literature Cited

Flather, Curtis H., Kenneth R. Wilson, Denis J. Dean, and William C. McComb. (1997). “Identifying gaps in conservation networks: of indicators and uncertainty in geographic-based analyses.” Ecological Applications. 7(2): 531-542.

Jennings, Michael J. (2000). “Gap analysis: concepts, methods, and recent results.” Landscape Ecology. 15: 5-20.

Scott, J. Michael, Davis, F., Csuti, B., Noss R., Butterfield, B., Groves, C., Anderson, H., Caicco, S., D’Erchia, F., Edwards, T.C., Jr., Ulliman, J., Wright, G. 1993. “Gap analysis: a geographic approach to biodiversity protection. Wildlife Monographs. 123:1-41.

Stoms, David M. 1994. “Scale dependence of species richness maps.” Professional Geographer. 46(3): 346-358.

USGS website. . Last accessed December 3, 2006.Rey alejo 17:46, 6 December 2006 (UTC)
 * Comment: Sounds good. You also have academic references included, which is laudable. Perhaps something could be added in the initial paragraph that explains what gap analysis is used for these days in wildife conservation beyond the original methods described by Scott et al. and Jennings. Referring to a general ecology or conservation biology textbook might provide ideas with this regard (e.g., Groom et al.'s Principles of Conservation Biology (3rd ed.), Sunderland, MA: Sinauer, pp. 518-521). It might also be a good idea to bear in mind that the reader will be uninitiated in ecology/conservation biology, and so technical explanations may have to give way to clear and easy-to-understand narrative. An article for gap analysis (conservation) exists. Perhaps you can integrate your writing there. Cheers, AppleJuggler 06:42, 11 December 2006 (UTC)
 * I have added the text into the article at Gap analysis (conservation). Thanks @Rey alejo for writing this! Hanif Al Husaini (talk) 09:47, 16 April 2022 (UTC)

Wiki Education assignment: Landscape Restoration
— Assignment last updated by Danimilkweed (talk) 17:59, 30 April 2024 (UTC)