Climate change may have minor impact on zooplankton functional diversity in the Mediterranean Sea

Aim To assess the impact of climate change on the functional diversity of marine zooplankton communities. Location The Mediterranean Sea. Methods We used the functional traits and geographic distributions of 106 copepod species to estimate the zooplankton functional diversity of Mediterranean surface assemblages for the 1965–1994 and 2069–2098 periods. Multiple environmental niche models were trained at the global scale to project the species habitat suitability in the Mediterranean Sea and assess their sensitivity to climate change predicted by several scenarios. Simultaneously, the species traits were used to compute a functional dendrogram from which we identified seven functional groups and estimated functional diversity through Faith's index. We compared the measured functional diversity to the one originated from null models to test if changes in functional diversity were solely driven by changes in species richness. Results All but three of the 106 species presented range contractions of varying intensity. A relatively low decrease of species richness (−7.42 on average) is predicted for 97% of the basin, with higher losses in the eastern regions. Relative sensitivity to climate change is not clustered in functional space and does not significantly vary across the seven copepod functional groups defined. Changes in functional diversity follow the same pattern and are not different from those that can be expected from changes in richness alone. Main conclusions Climate change is not expected to alter copepod functional traits distribution in the Mediterranean Sea, as the most and the least sensitive species are functionally redundant. Such redundancy should buffer the loss of ecosystem functions in Mediterranean zooplankton assemblages induced by climate change. Because the most negatively impacted species are affiliated to temperate regimes and share Atlantic biogeographic origins, our results are in line with the hypothesis of increasingly more tropical Mediterranean communities

Functional biogeography of oceanic islands and the scaling of functional diversity in the Azores

Analyses of species-diversity patterns of remote islands have been crucial to the development of biogeographic theory, yet little is known about corresponding patterns in functional traits on islands and how, for example, they may be affected by the introduction of exotic species. We collated trait data for spiders and beetles and used a functional diversity index (FRic) to test for nonrandomness in the contribution of endemic, other native (also combined as indigenous), and exotic species to functional-trait space across the nine islands of the Azores. In general, for both taxa and for each distributional category, functional diversity increases with species richness, which, in turn scales with island area. Null simulations support the hypothesis that each distributional group contributes to functional diversity in proportion to their species richness. Exotic spiders have added novel trait space to a greater degree than have exotic beetles, likely indicating greater impact of the reduction of immigration filters and/or differential historical losses of indigenous species. Analyses of species occurring in native-forest remnants provide limited indications of the operation of habitat filtering of exotics for three islands, but only for beetles. Although the general linear (not saturating) pattern of trait-space increase with richness of exotics suggests an ongoing process of functional enrichment and accommodation, further work is urgently needed to determine how estimates of extinction debt of indigenous species should be adjusted in the light of these findings

The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats

The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yet—undescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well

Representing taxonomic, phylogenetic and functional diversity: New challenges for Mediterranean marine-protected areas

François Guilhaumon [et al.]Aim: To assess gaps in the representation of taxonomic, phylogenetic and functional diversity among coastal fishes in Mediterranean marine-protected areas (MPAs).Location: Mediterranean SeaMethods: We first assessed gaps in the taxonomic representation of the 340 coastal fish species in Mediterranean MPAs, with representation targets (the species range proportion to be covered by MPAs) set to be inversely proportional to species’ range sizes. We then asked whether MPAs favoured representation of phylogenetically and functionally more distinct species or whether there was a tendency to favour less distinctive ones. We finally evaluated the overall conservation effectiveness of the MPAs using a metric that integrates species’ phylogenetic and functional relationships and targets achievement. The effectiveness of the MPA system at protecting biodiversity was assessed by comparison of its achievements against a null model obtained by siting current MPAs at random over the study area.Results: Among the coastal fish species analysed, 16 species were not covered by any MPA. All the remaining species only partially achieved the pre-defined representation target. The current MPA system missed fewer species than expected from siting MPAs at random. However, c. 70% of the species did not achieve better protection in the current MPAs than expected from siting MPAs at random. Functional and evolutionary distinctiveness were weakly correlated with target achievement. The observed coverage of taxonomic, phylogenetic and functional diversity was not different or lower than expected from siting MPAs at random.Main conclusions: The Mediterranean MPA system falls short in meeting conservation targets for coastal fish taxonomic diversity, phylogenetic diversity and functional diversity. Mediterranean MPAs do not encompass more biodiversity than expected by chance. This study reveals multiple ongoing challenges and calls for regional collaboration for the extension of the Mediterranean system of MPAs to meet international commitments and reduce the ongoing loss of marine biodiversity.M.B.A. also acknowledges the Integrated Program of IC&DT Call No. 1/SAESCTN/ALENT-07-0224-FEDER-001755, the Spanish Research Council (CSIC) and the Danish NSF for support of his research.Peer reviewe

Biodiversidade e Alterações Climáticas na Península Ibérica/ Biodiversidad y Alteraciones Climáticas en la Península Ibérica

Varias fueron las personas que contribuyeron, directa o indirectamente, para la realización de este proyecto. Debemos agradecimientos, en particular, a Ángel Felicísimo y Carlos Villaba (por el procesamiento de los datos climáticos actuales), Margarita del Dedo Garcimartín por el apoyo técnico y de gestión de la base de datos fotográfica del proyecto, Maria Triviño (por la gestion de las bases de datos biológicas en la fase inicial del proyecto), Rui Raimundio (por las traducciones), Alexandre Diniz Filho e Thiago Rangel (por la colaboración en el proyecto BIOIMPACTO , que fue el origen de la producción del software BIOENSEMBLES usado para modelar las distribuciones de las especies), Alejandro Rozenfeld (por la programación de BIO-GIS, usado para hacer algunos de los mapas que se presentan). Igualmente debemos agradecer al Ministerio de Medio Ambiente, Medio Rural y Marino y en particular a la Dirección General de Medio Natural y Política Forestal por la información biológica y la cartografía aportadas. Así mismo a la Oficina Española de Cambio Climático y a la Agencia Espanola de Meteorología por el apoyo y los datos aportados para este proyecto. También agradecer al Instituto para a Conservacão da Natureza e Biodiversidade, la Unidad Biogeográfica de Alentejo de la Universidad de Évora y al Instituto de Meteorología portugués por la información climática y de distribución de especies aportada. La revisión del presente libro, contó, además con la colaboración de diversas personas. En este contexto agradecemos a Márcia Barbosa por la revisión preliminar de los mapas de distribución. Por las revisiones finales del manuscrito a José Carlos Brito (anfíbios y reptiles), Martin Melo (aves), Pedro Beja (mamiferos) y Ângela Lomba (texto).Peer Reviewe

Functional diversity of fish in estuaries at a global extent

Biodiversity is currently viewed as a framework encompassing multiple facets of the variety of life, including taxonomic and functional aspects. Species richness and composition of fish assemblages in estuaries is defined by global to local processes acting on community colonization. The present study further investigates how biodiversity of fish assemblages varies among estuaries globally, by simultaneously analysing taxonomic and functional richness and diversity of assemblages. A comprehensive worldwide database was compiled on the fish assemblage composition and environmental characteristics of estuaries. In addition, functional attributes of the fish species were characterized such as body size, habitat use and trophic ecology. We investigated the relationship between taxonomic and functional aspects of biodiversity, i.e. the match or mismatch between the two. We also explored how functional diversity of fish assemblages varied among estuaries globally and related to environmental features of estuaries, i.e. historic and contemporary, global and local constraints. The results are explored in the context of ecosystem functioning and resilience, and outcomes relevant to assist in prioritizing conservation efforts are highlighted

Species-area relationships as a tool for the conservation of benthic invertebrates in Italian coastal lagoons

Over the recent decades, the preservation of coastal and estuarine waters has been recognised as a priority at national and international levels. At the European scale, the Water Framework Directive (WFD) was established with the aim to achieve a good ecological status of all significant water bodies by the year 2015. Among the descriptors used to define the ecological status of water bodies, taxonomic diversity (usually species richness) is a widespread metric employed across taxa and habitats. However, species richness is known to increase with area at a decelerating rate, producing the species area relationship (SAR). Thus, removing the effect of area (even in case of low magnitude), is mandatory before comparing species richness between sites. Here we tested recently developed multi-model SARs as a standardisation tool for comparing benthic species richness (annelids, arthropods, molluscs and total species richness) in 18 Italian coastal lagoons with a surface area ranging from 0.19 to 552 km(2), i.e. three orders of magnitude. However, the sampling effort was often incompletely described and certainly heterogeneous among the studies retrieved from the database. Therefore, we used the number of studies as a proxy for the sampling effort in each lagoon and estimated species richness from observed values using non-parametric occurrence-based estimators. We further corrected for bias that might be induced by sampling efforts being unrepresentative for the surface area of different lagoons. After applying these corrections, we estimated that c. 25-30% of species richness could be explained by surface area. We investigated the spatial congruence of species richness patterns across taxa and showed that molluscs could serve as a potential surrogate for total macro-invertebrate species richness. We further found that the intensity of conservation focus and the gradient of ecological status are decoupled in Italian coastal lagoons. More generally, our study pave the way for the use of flexible tools for the comparison of species richness across water bodies in the context of the WFD

Slow growth of the overexploited milk shark Rhizoprionodon acutus affects its sustainability in West Africa

Age and growth of Rhizoprionodon acutus were estimated from vertebrae age bands. From December 2009 to November 2010, 423 R. acutus between 37 and 112 cm total length (L-T) were sampled along the Senegalese coast. Marginal increment ratio was used to check annual band deposition. Three growth models were adjusted to the length at age and compared using Akaike's information criterion. The Gompertz growth model with estimated size at birth appeared to be the best and resulted in growth parameters of L = 13955 (L-T) and K = 017 year(-1) for females and L = 12652 (L-T) and K = 018 year(-1) for males. The largest female and male examined were 8 and 9 years old, but the majority was between 1 and 3 years old. Ages at maturity estimated were 58 and 48 years for females and males, respectively. These results suggest that R. acutus is a slow-growing species, which render the species particularly vulnerable to heavy fishery exploitation. The growth parameters estimated in this study are crucial for stock assessments and for demographic analyses to evaluate the sustainability of commercial harvests

The island species–area relationship: biology and statistics

Copyright © 2011 Blackwell Publishing Ltd.AIM: We conducted the most extensive quantitative analysis yet undertaken of the form taken by the island species–area relationship (ISAR), among 20 models, to determine: (1) the best-fit model, (2) the best-fit model family, (3) the best-fit ISAR shape (and presence of an asymptote), (4) system properties that may explain ISAR form, and (5) parameter values and interpretation of the logarithmic implementation of the power model. LOCATION: World-wide. METHODS: We amassed 601 data sets from terrestrial islands and employed an information-theoretic framework to test for the best-fit ISAR model, family, and shape, and for the presence/absence of an asymptote. Two main criteria were applied: generality (the proportion of cases for which the model provided an adequate fit) and efficiency (the overall probability of a model, when adequate, being the best at explaining ISARs; evaluated using the mean overall AICc weight). Multivariate analyses were used to explore the potential of island system properties to explain trends in ISAR form, and to describe variation in the parameters of the logarithmic power model. RESULTS: Adequate fits were obtained for 465 data sets. The simpler models performed best, with the power model ranked first. Similar results were obtained at model family level. The ISAR form is most commonly convex upwards, without an asymptote. Island system traits had low descriptive power in relation to variation in ISAR form. However, the z and c parameters of the logarithmic power model show significant pattern in relation to island system type and taxon. MAIN CONCLUSIONS: Over most scales of space, ISARs are best represented by the power model and other simple models. More complex, sigmoid models may be applicable when the spatial range exceeds three orders of magnitude. With respect to the log power model, z-values are indicative of the process(es) establishing species richness and composition patterns, while c-values are indicative of the realized carrying capacity of the system per unit area. Variation in ISAR form is biologically meaningful, but the signal is noisy, as multiple processes constrain the ecological space available within island systems and the relative importance of these processes varies with the spatial scale of the system

marxan: Initialise zenodo

This R package contains decision support tools for reserve selection using Marxan