Widespread extinction is a predicted ecological consequence of global warming. Extinction risk under climate change scenarios is a function of distribution breadth. Focusing on trees and birds of the eastern United States, we used joint climate and environment models to examine fit and climate change vulnerability as a function of distribution breadth. We found that extinction vulnerability increases with decreasing distribution size. We also found that model fit decreases with decreasing distribution size, resulting in high prediction uncertainty among narrowly distributed species. High prediction uncertainty creates a conservation dilemma in that excluding these species under-predicts extinction risk and favors mistaken inaction on global warming. By contrast, including narrow endemics results in over-predicting extinction risk and promotes mistaken inaction on behalf of individual species prematurely considered doomed to extinction.

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We investigated the concordance of taxonomic richness patterns and their environmental correlates for assemblages of benthic macroinvertebrates, riparian birds, sedimentary diatoms, fish, planktonic crustaceans, and planktonic rotifers in 186 northeastern U.S. lakes. Taxon counts were standardized with respect to sampling effort using rarefaction. The degree of concordance among assemblage richness measures was low, but this was at least partly attributable to measurement precision. Aspects of lake morphology (area, depth) superseded other environmental features (climate, human development, water chemistry, nearshore physical habitat) as correlates of assemblage richness and were the strongest source of concordance. The benthic macroinvertebrates, birds, fish, and zooplankton all showed positive associations between richness and lake area. The diatoms showed negligible associations between richness and area and negative associations between richness and depth. Associations with human development were much weaker than with lake morphology and varied from positive (fish, planktonic crustaceans) to negative (diatoms). We conclude that taxonomic richness alone may be of ambiguous value as an indicator of biological integrity in lakes and that its natural drivers must be controlled for prior to assessing anthropogenic effects. Résumé : Nous avons étudié la concordance de profils de diversité taxonomique avec leurs corrélats environnementaux chez des groupements de macroinvertébrés benthiques, d'oiseaux de rivage, de diatomées sédimentaires, de poissons et de crustacés et de rotifères planctoniques dans 186 lacs du nord-est des États-Unis. Nous avons normalisé les dénombrements des taxons en fonction de l'effort d'échantillonnage en appliquant le principe de raréfaction. Le degré de concordance entre les mesures de diversité des groupements était faible, mais cela était au moins en partie attribuable à la précision des mesures. Certains aspects de la morphologie des lacs (superficie, profondeur) étaient mieux corrélés à la diversité des groupements que d'autres caractéristiques environnementales (climat, développements anthropiques, chimie de l'eau, habitat riverain) et étaient les plus fortes sources de concordance. Nous avons observé des corrélations positives entre la diversité et la superficie des lacs chez les macroinvertébrés benthiques, les oiseaux, les poissons et le zooplankton. Il y avait des corrélations négligeables entre la diversité et la superficie et des corrélations négatives entre la diversité et la profondeur chez les diatomées. Les corrélations avec les développements anthropiques étaient beaucoup plus faibles qu'avec la morphologie des lacs et variaient de positives (poissons, crustacés planctoniques) à négatives (diatomées). Nous concluons que la seule diversité taxonomique peut constituer un indicateur ambigu de l'intégrité biologique des lacs et que les facteurs naturels qui la déterminent doivent être connus avant que soient évalués les effets anthropiques.

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Recovery efforts for threatened and endangered species often must be initiated with incomplete data. The outcomes of such efforts are difficult to predict, which makes monitoring the progress of recovery efforts an integral part of the recovery process. We evaluated the role of monitoring in recovery plans for 181 species listed as threatened and endangered under the U.S. Endangered Species Act. We considered both the extent to which monitoring tasks were proposed as part of the recovery effort and the extent to which the tasks proposed were actually implemented. In general, tasks devoted to tracking the species' population trend were more likely to be proposed and implemented than were other monitoring activities (e.g., those devoted to the species' demographics, its habitat requirements, or the impact of predators, competitors, and exotics). We found that the extent and nature of the monitoring proposed and implemented appeared to reflect taxonomic biases that exist throughout the recovery process and were little influenced either by the level of understanding of the species' biology or by the recovery priority assigned to the species. In particular, monitoring efforts did not adequately address the specific threats affecting species. Proposals for, and implementation of, monitoring progress toward recovery goals were independent of the type of criteria defined in the plans (e.g., population level and habitat extent), although population‐related criteria were disproportionately common. Based on these findings, we caution against an overemphasis on focal species monitoring, especially when such an emphasis leads to the reduction or exclusion of other types of monitoring. We also recommend that species‐specific attributes factor more prominently in the development of monitoring to avoid monitoring action that is otherwise unnecessary.