The sizes of species’ geographic ranges

Gaston, K.J. and Fuller, R. (2009) The sizes of species’ geographic ranges. Journal of Applied Ecology, 46 1: 1-9. doi:10.1111/j.1365-2664.2008.01596.x

Author Gaston, K.J.
Fuller, R.
Title The sizes of species’ geographic ranges
Journal name Journal of Applied Ecology   Check publisher's open access policy
ISSN 0021-8901
Publication date 2009-02
Year available 2008
Sub-type Article (original research)
DOI 10.1111/j.1365-2664.2008.01596.x
Volume 46
Issue 1
Start page 1
End page 9
Total pages 9
Editor Kerby, G.
Place of publication United Kingdom
Publisher Wiley-Blackwell Publishing
Language eng
Subject C1
050202 Conservation and Biodiversity
960899 Flora, Fauna and Biodiversity of Environments not elsewhere classified
Abstract 1. Geographic range size and how it changes through time is one of the fundamental ecological and evolutionary characteristics of a species, and a strong predictor of extinction risk. However, the measurement of range size remains a substantial challenge. Indeed, there is significant confusion in the literature as to how this should be done, particularly in the context of the distinction between the fundamentally different concepts of extent of occurrence (EOO) and area of occupancy (AOO), and the use of these quantities, including in assessments of the threat status of species. 2. Here we review the different approaches to determining the geographic distributions of species, the measurement of their range sizes, the relationships between the two, and other difficulties posed by range size measurement (especially those of range discontinuities when measuring EOO, and spatial scale when measuring AOO). 3. We argue that it is important to (i) distinguish the estimation of the distribution of a species from the measurement of its geographic range size; (ii) treat measures of EOO and AOO as serving different purposes, rather than regarding them as more or less accurate ways of measuring range size; and (iii) measure EOO including discontinuities in habitat or occupancy. 4. Synthesis and applications. With the availability and collation of extensive data sets on species occurrences, a rapidly increasing number of studies are investigating geographic range size, and particularly how various measures of range size predict macroecological patterns and inform assessments of the conservation status of species and areas. The distinction between EOO and AOO is becoming blurred in many contexts, but most particularly in that of threatened species assessments for Red Listing. Continued progress in these fields demands greater clarity in the meaning and derivation of measures of geographic range size. The two principal measures serve different purposes, and should not be regarded as alternatives that simply differ in accuracy.
Keyword area of occupancy
extent of occurrence
geographic distribution
range limits
Red List
Q-Index Code C1
Q-Index Status Provisional Code

Document type: Journal Article
Sub-type: Article (original research)
Collections: AEDA Publications
Spatial Ecology Lab Publications
School of Biological Sciences Publications
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Citation counts: TR Web of Science Citation Count  Cited 142 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 156 times in Scopus Article | Citations
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Created: Wed, 06 Jan 2010, 13:18:19 EST by Hayley Ware on behalf of School of Biological Sciences