Assessing the Threat Status of Ecological Communities
- 16 March 2009
- journal article
- review article
- Published by Wiley in Conservation Biology
- Vol. 23 (2), 259-274
- https://doi.org/10.1111/j.1523-1739.2008.01158.x
Abstract
Conservationists are increasingly interested in determining the threat status of ecological communities as a key part of their planning efforts. Such assessments are difficult because of conceptual challenges and a lack of generally accepted criteria. We reviewed 12 protocols for assessing the threat status of communities and identified conceptual and operational issues associated with developing a rigorous, transparent, and universal set of criteria for assessing communities, analogous to the International Union for Conservation of Nature (IUCN) Red List standards for species. We examined how each protocol defines a community and its extinction and how each applies 3 overarching criteria: decline in geographic distribution, restricted geographic distribution, and changes to ecological function. The protocols vary widely in threshold values used to assess declines and distribution size and the time frames used to assess declines, leading to inconsistent assessments of threat status. Few of the protocols specify a scale for measuring distribution size, although assessment outcomes are highly sensitive to scale. Protocols that apply different thresholds for species versus communities tend to require greater declines and more restricted distributions for communities than species to be listed in equivalent threat categories. Eleven of the protocols include a reduction in ecological function as a criterion, but almost all assess it qualitatively rather than quantitatively. We argue that criteria should be explicit and repeatable in their concepts, parameters, and scale, applicable to a broad range of communities, and address synergies between types of threats. Such criteria should focus on distribution size, declines in distribution, and changes to key ecological functions, with the latter based on workable proxies for assessing the severity, scope, and immediacy of degradation. Threat categories should be delimited by thresholds that are assessed at standard scales and are logically consistent with the viability of component species and important ecological functionsKeywords
This publication has 33 references indexed in Scilit:
- The interpretation, assessment and conservation of ecological communitiesEcological Management & Restoration, 2009
- Quantification of Extinction Risk: IUCN's System for Classifying Threatened SpeciesConservation Biology, 2008
- Getting the biodiversity intactness index right: the importance of habitat degradation dataGlobal Change Biology, 2006
- Post‐fire recovery of ant communities in Submediterranean Pinus nigra forestsEcography, 2005
- The habitat hectares approach to vegetation assessment: An evaluation and suggestions for improvementEcological Management & Restoration, 2004
- Scale Dependency of Rarity, Extinction Risk, and Conservation PriorityConservation Biology, 2003
- Disturbances and structural development of natural forest ecosystems with silvicultural implications, using Douglas-fir forests as an exampleForest Ecology and Management, 2002
- Sensitivity analyses of decision rules in World Conservation Union (IUCN) Red List criteria using Australian plantsBiological Conservation, 2000
- Ecosystems as conservation targetsTrends in Ecology & Evolution, 1996
- Continuum Concept, Ordination Methods, and Niche TheoryAnnual Review of Ecology and Systematics, 1985