Assessing Climate Change Vulnerability of Breeding Birds in Arctic ...

We chose to use the 2-m overlay in thevulnerability assessment as a plausiblefuture to capture the potentially importantimpacts of sea level rise for species withcoastally limited distributions. The 2-meterdata shifted the sea-level rise score from“neutral” to “slightly increasedvulnerability” for 7 of the 54 species.Sensitivity survey and expert solicitationWe asked individual species experts to scorethe sensitivity factors of the CCVI (13 of 23;see Fig 2.2.). Some factors have subcategories,and others require a geospatialoverlay to assess. Most species experts wereagency, academic, non-governmental, orprivate industry scientists with advanceddegrees that have spent multiple yearsstudying some aspect of their focal speciesand were familiar with the respective bodyof literature. We solicited responses from 83species experts of which 51 responded bycompleting sensitivity surveys and providinginformation on one measure of indirectclimate exposure – “human climatemitigation” (Appendix C). The sensitivitysurveys were based on those used in avulnerability assessment conducted in theState of Florida using the CCVI (Dubois etal. 2011).Experts were instructed to respond toquestions taken verbatim from the CCVIguidance document, provide citations andwritten justifications for their responses, andassign a “confidence level” to their responseusing a 1-5 scale. Sensitivity surveyresponses were entered into the CCVI andrun with the various climate exposure andother geospatial inputs to generatepreliminary climate change vulnerabilityresults for the 54 species.We presented preliminary results (notreported here) during a workshop inAnchorage, Alaska on December 7-9 th ,2011. The 31 participants represented amajority of the species’ experts whoreturned a sensitivity survey. It becameclear; both in reading survey responses andthrough discussions at the workshop, thatindividual experts interpreted somequestions differently. In addition, expertsexpressed some discomfort in answeringsensitivity questions that also required someunderstanding and/or speculation aboutclimate exposure and ecosystem responses.To address these issues, a sub-group ofsix avian experts (Appendix D) and WCSclimate change program staff revised theproblematic sensitivity factor questions afterthe workshop and re-evaluated the originalresponses of the larger expert group in lightof this agreed upon language andstandardized interpretation (Appendix F).The original responses and supportinginformation provided by species expertswere circulated to the sub-group and weasked all six experts to revise the originalresponses on their own. We then met as agroup to discuss any suggested changes tothe original scores and to explore anywithin-group differences in the revisedresponses. We did not strive to reachconsensus, but sought to ensure that relevantnuances in reasoning were recorded andquestion interpretation was consistent.Because the CCVI can accommodatemultiple scores for any one factor, all of there-evaluated responses were used togenerate the revised vulnerabilityassessment results.Visualizing species sensitivity and climatechange vulnerabilityWe illustrate similarities and differencesbetween the sensitivities and climate changevulnerabilities of the 54 bird species with aprinciple components analysis (PCA) basedon a variance-covariance matrix (because ofthe standard scale of the variables) andEuclidean distance measure using PASTsoftware (Hammer et al. 2001). While not anideal multivariate method for categorical16