• Energy Research

We identified hotspots of terrestrial vertebrate species diversity in Europe and adjacent islands. Moreover, we assessed the extent to which by the end of the 21st century such hotspots will be exposed to average monthly temperature and precipitation patterns which can be regarded as extreme if compared to the climate experienced during 1950-2000. In particular, we considered the entire European sub-continent plus Turkey and a total of 1149 species of terrestrial vertebrates. For each species, we developed species-specific expert-based distribution models (validated against field data) which we used to calculate species richness maps for mammals, breeding birds, amphibians, and reptiles. Considering four global circulation model outputs and three emission scenarios, we generated an index of risk of exposure to extreme climates, and we used a bivariate local Moran’s I to identify the areas with a significant association between hotspots of diversity and high risk of exposure to extreme climates. Our results outline that the Mediterranean basin represents both an important hotspot for biodiversity and especially for threatened species for all taxa. In particular, the Iberian and Italian peninsulas host particularly high species richness as measured over all groups, while the eastern Mediterranean basin is particularly rich in amphibians and reptiles; the islands (both Macaronesian and Mediterranean) host the highest richness of threatened species for all taxa occurs. Our results suggest that the main hotspots of biodiversity for terrestrial vertebrates may be extensively influenced by the climate change projected to occur over the coming decades, especially in the Mediterranean bioregion, posing serious concerns for biodiversity conservation. PLoS ONE, 8 (9) ISSN:1932-6203

Pour faire face à la crise mondiale actuelle de la biodiversité, les gouvernements ont fixé des objectifs stratégiques et adopté des indicateurs pour suivre les progrès vers leur réalisation. La projection des impacts probables sur la biodiversité de différentes décisions politiques permet aux décideurs de comprendre si et comment ces objectifs peuvent être atteints. Nous avons projeté les tendances de deux indicateurs largement utilisés de l'abondance de la population : l'abondance moyenne géométrique, équivalente à l'indice de la planète vivante et le risque d'extinction (l'indice de la liste rouge) dans différents scénarios de changement climatique et d'utilisation des terres. En les testant sur des espèces terrestres de carnivores et d'ongulés, nous avons constaté que les deux indicateurs diminuent régulièrement et que, d'ici 2050, dans un scénario de statu quo, l'abondance moyenne géométrique des populations diminue de 18 à 35 %, tandis que le risque d'extinction augmente pour 8 à 23 % des espèces, en fonction des hypothèses sur les réponses des espèces au changement climatique. BAU ne parviendra donc pas à atteindre l'objectif 12 de la Convention sur la diversité biologique consistant à améliorer l'état de conservation des espèces menacées connues. Un scénario de développement durable alternatif réduit à la fois le risque d'extinction et les pertes de population par rapport au BAU et pourrait entraîner une augmentation de la population. Notre approche des réponses des espèces modèles aux changements mondiaux met l'accent sur les scénarios directement au niveau des espèces, prenant ainsi en compte une dimension supplémentaire de la biodiversité et ouvrant la voie à l'inclusion de fondations écologiques plus solides dans les futures évaluations des scénarios de biodiversité. Para abordar la actual crisis mundial de biodiversidad, los gobiernos han establecido objetivos estratégicos y han adoptado indicadores para monitorear el progreso hacia su logro. La proyección de los posibles impactos en la biodiversidad de las diferentes decisiones políticas permite a los responsables de la toma de decisiones comprender si se pueden cumplir estos objetivos y cómo. Proyectamos tendencias en dos indicadores ampliamente utilizados de abundancia poblacional, la Abundancia Media Geométrica, equivalente al Índice de Planeta Vivo y el riesgo de extinción (el Índice de la Lista Roja) bajo diferentes escenarios de cambio climático y de uso de la tierra. Probando estos en especies de carnívoros y ungulados terrestres, encontramos que ambos indicadores disminuyen constantemente y, para 2050, en un escenario de negocios como de costumbre (BAU), la abundancia de la población media geométrica disminuye en un 18–35%, mientras que el riesgo de extinción aumenta para el 8–23% de las especies, dependiendo de los supuestos sobre las respuestas de las especies al cambio climático. Por lo tanto, BAU no cumplirá con la meta 12 del Convenio sobre la Diversidad Biológica de mejorar el estado de conservación de las especies amenazadas conocidas. Un escenario alternativo de desarrollo sostenible reduce tanto el riesgo de extinción como las pérdidas de población en comparación con BAU y podría conducir a un aumento de la población. Nuestro enfoque para modelar las respuestas de las especies a los cambios globales lleva el enfoque de los escenarios directamente al nivel de las especies, teniendo en cuenta así una dimensión adicional de la biodiversidad y allanando el camino para incluir fundamentos ecológicos más sólidos en futuras evaluaciones de escenarios de biodiversidad. To address the ongoing global biodiversity crisis, governments have set strategic objectives and have adopted indicators to monitor progress toward their achievement. Projecting the likely impacts on biodiversity of different policy decisions allows decision makers to understand if and how these targets can be met. We projected trends in two widely used indicators of population abundance Geometric Mean Abundance, equivalent to the Living Planet Index and extinction risk (the Red List Index) under different climate and land-use change scenarios. Testing these on terrestrial carnivore and ungulate species, we found that both indicators decline steadily, and by 2050, under a Business-as-usual (BAU) scenario, geometric mean population abundance declines by 18–35% while extinction risk increases for 8–23% of the species, depending on assumptions about species responses to climate change. BAU will therefore fail Convention on Biological Diversity target 12 of improving the conservation status of known threatened species. An alternative sustainable development scenario reduces both extinction risk and population losses compared with BAU and could lead to population increases. Our approach to model species responses to global changes brings the focus of scenarios directly to the species level, thus taking into account an additional dimension of biodiversity and paving the way for including stronger ecological foundations into future biodiversity scenario assessments. ولمعالجة أزمة التنوع البيولوجي العالمية المستمرة، وضعت الحكومات أهدافاً استراتيجية واعتمدت مؤشرات لرصد التقدم المحرز نحو تحقيقها. إن توقع التأثيرات المحتملة على التنوع البيولوجي لقرارات السياسة المختلفة يسمح لصانعي القرار بفهم ما إذا كان يمكن تحقيق هذه الأهداف وكيفية تحقيقها. توقعنا اتجاهات في مؤشرين يستخدمان على نطاق واسع لوفرة السكان متوسط الوفرة الهندسية، أي ما يعادل مؤشر الكوكب الحي ومخاطر الانقراض (مؤشر القائمة الحمراء) في ظل سيناريوهات مختلفة لتغير المناخ واستخدام الأراضي. عند اختبارها على الأنواع آكلة اللحوم البرية وذوات الحوافر، وجدنا أن كلا المؤشرين ينخفضان بشكل مطرد، وبحلول عام 2050، في ظل سيناريو العمل كالمعتاد (BAU)، ينخفض متوسط وفرة السكان الهندسي بنسبة 18-35 ٪ بينما تزداد مخاطر الانقراض لـ 8-23 ٪ من الأنواع، اعتمادًا على الافتراضات حول استجابات الأنواع لتغير المناخ. وبالتالي، ستفشل جامعة البلقاء التطبيقية في تحقيق الهدف 12 من اتفاقية التنوع البيولوجي المتمثل في تحسين حالة حفظ الأنواع المعروفة المهددة بالانقراض. يقلل سيناريو التنمية المستدامة البديلة من خطر الانقراض والخسائر السكانية مقارنةً بوحدات العمل الاعتيادية ويمكن أن يؤدي إلى زيادة عدد السكان. إن نهجنا في استجابات الأنواع النموذجية للتغيرات العالمية يجلب تركيز السيناريوهات مباشرة إلى مستوى الأنواع، وبالتالي يأخذ في الاعتبار بُعدًا إضافيًا للتنوع البيولوجي ويمهد الطريق لإدراج أسس بيئية أقوى في تقييمات سيناريوهات التنوع البيولوجي المستقبلية.

SignificanceDespite the critical threat of habitat fragmentation, global patterns of fragmentation and its relationship to extinction risk have not been quantified for any major taxon. We developed high-resolution models that provide a global assessment of the degree of habitat fragmentation impacting the world’s terrestrial mammals. Results demonstrate that mammals with more fragmentation are at greater risk of extinction, even after accounting for the effects of key macroecological predictors, such as body size and geographic range size. Species with higher fragmentation had smaller ranges and a lower proportion of high-suitability habitat within their range, and most high-suitability habitat occurred outside of protected areas, further elevating extinction risk. Quantification of habitat fragmentation will help guide strategic priorities for global mammal conservation.

Assessing Biodiversity Declines Understanding human impact on biodiversity depends on sound quantitative projection. Pereira et al. (p. 1496 , published online 26 October) review quantitative scenarios that have been developed for four main areas of concern: species extinctions, species abundances and community structure, habitat loss and degradation, and shifts in the distribution of species and biomes. Declines in biodiversity are projected for the whole of the 21st century in all scenarios, but with a wide range of variation. Hoffmann et al. (p. 1503 , published online 26 October) draw on the results of five decades' worth of data collection, managed by the International Union for Conservation of Nature Species Survival Commission. A comprehensive synthesis of the conservation status of the world's vertebrates, based on an analysis of 25,780 species (approximately half of total vertebrate diversity), is presented: Approximately 20% of all vertebrate species are at risk of extinction in the wild, and 11% of threatened birds and 17% of threatened mammals have moved closer to extinction over time. Despite these trends, overall declines would have been significantly worse in the absence of conservation actions.

The daily energy requirements of animals are determined by a combination of physical and physiological factors, but food availability may challenge the capacity to meet nutritional needs. Western gorillas (Gorilla gorilla) are an interesting model for investigating this topic because they are folivore-frugivores that adjust their diet and activities to seasonal variation in fruit availability. Observations of one habituated group of western gorillas in Bai-Hokou, Central African Republic (December 2004-December 2005) were used to examine seasonal variation in diet quality and nutritional intake. We tested if during the high fruit season the food consumed by western gorillas was higher in quality (higher in energy, sugar, fat but lower in fibre and antifeedants) than during the low fruit season. Food consumed during the high fruit season was higher in digestible energy, but not any other macronutrients. Second, we investigated whether the gorillas increased their daily intake of carbohydrates, metabolizable energy (KCal/g OM), or other nutrients during the high fruit season. Intake of dry matter, fibers, fat, protein and the majority of minerals and phenols decreased with increased frugivory and there was some indication of seasonal variation in intake of energy (KCal/g OM), tannins, protein/fiber ratio, and iron. Intake of non-structural carbohydrates and sugars was not influenced by fruit availability. Gorillas are probably able to extract large quantities of energy via fermentation since they rely on proteinaceous leaves during the low fruit season. Macronutrients and micronutrients, but not digestible energy, may be limited for them during times of low fruit availability because they are hind-gut fermenters. We discuss the advantages of seasonal frugivores having large dietary breath and flexibility, significant characteristics to consider in the conservation strategies of endangered species.