A Quantitative Climate-Match Score for Risk-Assessment Screening of Reptile and Amphibian Introductions

Centre for Invasion Biology (CIB), Department of Botany & Zoology, Stellenbosch University, Matieland, Stellenbosch, Western Cape 7602, South Africa.
Environmental Management (Impact Factor: 1.72). 08/2009; 44(3):590-607. DOI: 10.1007/s00267-009-9311-y
Source: PubMed


Assessing climatic suitability provides a good preliminary estimate of the invasive potential of a species to inform risk assessment. We examined two approaches for bioclimatic modeling for 67 reptile and amphibian species introduced to California and Florida. First, we modeled the worldwide distribution of the biomes found in the introduced range to highlight similar areas worldwide from which invaders might arise. Second, we modeled potentially suitable environments for species based on climatic factors in their native ranges, using three sources of distribution data. Performance of the three datasets and both approaches were compared for each species. Climate match was positively correlated with species establishment success (maximum predicted suitability in the introduced range was more strongly correlated with establishment success than mean suitability). Data assembled from the Global Amphibian Assessment through NatureServe provided the most accurate models for amphibians, while ecoregion data compiled by the World Wide Fund for Nature yielded models which described reptile climatic suitability better than available point-locality data. We present three methods of assigning a climate-match score for use in risk assessment using both the mean and maximum climatic suitabilities. Managers may choose to use different methods depending on the stringency of the assessment and the available data, facilitating higher resolution and accuracy for herpetofaunal risk assessment. Climate-matching has inherent limitations and other factors pertaining to ecological interactions and life-history traits must also be considered for thorough risk assessment.

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Available from: Nicola Jane Van Wilgen
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    • "The models of Pyron et al. (2008), Rodda et al. (2009), and Van Wilgen et al. (2009) "
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    • "Overall, our findings suggest that the factors promoting establishment success among alien reptiles and amphibians are not necessarily the same as those promoting spread. For example, previous studies have found that climate match (Bomford et al. 2009; van Wilgen et al. 2009; Fujisaki et al. 2010; van Wilgen & Richardson 2012), native geographic range size (Allen et al. 2013; but see counter-example in Bomford et al. 2009) and introduction pathway (Rago et al. 2012) predict the probability of successful establishment, but these factors generally had negligible effects on spread rates in our analyses. Earlier studies of herpetofauna (Allen et al. 2013), mammals (Forsyth et al. 2004) and birds (Duncan et al. 2001) found that smaller species colonise larger geographic ranges. "
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    • "Cooper et al., 2008; Finer et al., 2008; van Wilgen et al., 2009; Lawler et al., 2010; Becker & Zamudio, 2011; Sandel et al., 2011; Hof et al., 2012), including analyses performed on fine spatial scales (e.g. Finer et al., 2008; van Wilgen et al., 2009; Becker & Zamudio, 2011). The maps may be affected by multiple sources of error, such as incomplete information on some species or in some areas, limited spatial resolution, and errors when digitizing the distribution ranges, which may influence the output of analyses based on these maps (Hurlbert & Jetz, 2007; Foody, 2011; Rocchini et al., 2011; Cant u-Salazar & Gaston, 2013). "
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