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Translocations to restore populations of endangered species are an important conservation tool, but a reliable diagnosis is needed to assess their success. We used capture-recapture modeling to analyze the adult apparent survival of released and resident tortoises in two translocation projects in Spain monitored for 14 and 29 years. We tested if long-term survival rates differ between released and resident individuals, if survival was lower during the phase of establishment (i.e. release cost), how long acclimation lasts and if increased density due to releases affects survival. We found lower survival of released tortoises during the phase of establishment (1 to 3 years) when residents were already present. After establishment, survival was very high and unaffected by density-dependence. Body condition before release was similar between recaptured and dead/missing tortoises, and did not predict establishment survival. Stochastic population viability analysis showed that success when releasing small numbers of individuals strongly depends upon adult long-term survival. Release of small second batches of tortoises was not sensitive to a growing population, regardless of its release timing. Our results highlight long-term survival as crucial in translocation projects of long-lived species, invalidating short-term (first year) survival assessment, when survival release cost does not match long-term survival. A release cost of different duration should be included in model estimation before modeling predictions. Releasing tortoises (for welfare of captive individuals or for mitigating human negative impacts) in an already established population is not recommended under most circumstances. Acclimation cost is followed by survival approaching wild counterparts. If this milestone is not achieved, the project needs to be carefully assessed to adopt other management options or should be stopped altogether., The regional governments of Catalonia and the Balearic Islands (Generalitat of Catalonia and the Govern de les Illes Balears) and Organismo Autónomo de Parques Nacionales (Ministerio Agricultura, Alimentación y Medio Ambiente, Gobierno de España) authorized our scientific work. Field work in the Ebro Delta and Minorca was partially funded by the Ebro Delta Natural Park, the Generalitat de Catalunya, the Institut Menorquí d'Estudis (IME), the Consell Insular de Menorca and the Spanish Ministry of Science and Technology (CICYT CGL2004-0473/BOS). AB is especially grateful to the Ebro Delta Natural Park staff that recognizes the importance of long-term monitoring programs. We are grateful to Evarist Coll from the GOB Menorca for kindly providing the released tortoises data. We thank several field workers who helped collect the data, especially Marta Massana, for their valuable assistance during several years, and Sam Pons and family for their friendly help and warm hospitality at Minorca. We are grateful to the two anonymous reviewers for improving the manuscript. We are also grateful to Elizabeth Rochon and Jacqueline Donoyan for improving the English on early draft.

Synthesis of the knowledge about Gull-billed Tern Gelochelidon nilotica diet in the Mediterranean area This work analyses diet composition and trophic diversity of the Gull-billed Tern in 11 colonies in the Mediterranean basin based on published papers and original data from the Ebro Delta (NE Spain). Spearman correlation and correspondence analysis were used to assess the relationship between diet characteristics (trophic diversity and composition) and geographic localization of colonies. Insects were predominant in the diet of the Gull-billed Tern in the Ebro Delta (77.6%), as well as for most of the populations studied (mean of 59.4 % by population). Within insects, coleopterans and orthopterans were the most consumed. For the populations preferring aquatic prey (two localities), crustaceans were the most consumed prey. Vertebrates were less abundant in number (median of 8.5 % by population) and within this group, amphibians were predominant. We did not find any similarity in the diet depending on the geographic proximity of the populations nor any relationship between latitude of population and trophic diversity (reciprocal of index of Simpson 1/H). Finally, in the Mediterranean basin the diet of the Gull-billed Tern is basically formed by insects caught in terrestrial habitats., Ce travail analyse le régime alimentaire de la Sterne hansel dans 11 colonies localisées en région Méditerranéenne à partir de travaux publiés et de données originales du delta de l’Èbre (NE Espagne). Nous avons utilisé le coefficient de corrélation de Spearman et l’analyse factorielle des correspondances pour déterminer s’il y a des relations entre le régime alimentaire (diversité trophique et composition) et la localisation géographique des colonies. Les insectes constituent la proie prédominante dans le régime alimentaire de la Sterne hansel du delta de l’Èbre (77,6 %) ainsi que dans la plupart des colonies (moyenne de 59,4 % par colonie). Parmi les insectes, les Coléoptères et les Orthoptères sont les plus consommés. Dans les populations où les proies aquatiques abondent (deux colonies), les crustacés sont les proies prédominantes. Les vertébrés sont numériquement peu abondants (médiane 8,5 % par colonie), les amphibiens étant les plus nombreux dans ce groupe. Les colonies les plus proches ne présentent pas une plus grande similarité dans le régime alimentaire et on ne trouve pas de relation entre la latitude des colonies et leur diversité trophique (inverse de l’indice de Simpson 1/H). Finalement, en région Méditerranéenne, le régime alimentaire de la Sterne hansel est constitué principalement d’insectes capturés dans les milieux terrestres., Bertolero Albert,Rivaes Sofia. Synthèse des connaissances sur le régime alimentaire de la Sterne hansel Gelochelidon nilotica en région méditerranéenne. In: Revue d'Écologie (La Terre et La Vie), tome 70, n°1, 2015. pp. 83-90.

International audience; Estimating the genetic variation and demographic trends of species in decline is of major concern in conservation genetics. This study contributes to understanding how historical and anthropogenic factors shape the distribution of current genetic diversity in one of the most endangered reptiles in Western Europe, the Hermann's tortoise Testudo hermanni hermanni. We used 17 microsatellite loci, chosen from a pyrosequencing library specifically developed for the subspecies to genotype eight populations distributed over about 30 sample localities covering almost the entire geographic distribution of the sub-species. The population genetic results reflect a very strong genetic structure and identify three major clusters among the Hermann's tortoise in the occidental Mediterranean basin: a continental cluster (Albera in Spain, Var in France and continental Italy), an insular cluster (Corsica, Sardinia and Sicily) and a cluster of mixed lineage (Minorca). Each of the eight studied populations is characterized by only one lineage except for Minorca, in which two lineages were identified. In contrast to what most empirical studies predict, the genetic diversity of the Hermann's tortoise is greater on islands than on the continent. Islands can therefore be considered as genetic sanctuaries with high conservation potential for this species, particularly in Corsica. Historical demographic patterns inferred with a generalized stepwise-mutation model (GSM) using maximum likelihood showed significant past demographic changes in only two of the eight sampled populations: a demographic bottleneck was detected in the Albera population (Spain) and a demographic expansion in Corsica (France). In contrast to what was argued in previous studies, these results indicate that the Hermann's tortoise lineage found in Corsica is autochthonous. The origin of both lineages found in Minorca remains speculative. Lastly, our study identifies the six most relevant management units (sensu Moritz, 1994) for conservation purposes on the basis that they represent a significant part of the evolutionary legacy of the species. Some conservation recommendations were proposed, in particular for the most threatened population in Albera.

Este artículo contiene 7 páginas, 3 figuras, 1 tabla., Studying colonisation is crucial to understand metapopulations, evolutionary ecology and species resilience to global change. Unfortunately, few empirical data are available because field monitoring that includes empty patches at large spatiotemporal scales is required. We examine the colonisation dynamics of a long-lived seabird over 34 years in the western Mediterranean by comparing population and individual data from both source colony and the newly-formed colonies. Since social information is not available, we hypothesize that colonisation should follow particular dispersal dynamics and personal information must be crucial in decision making. We test if adverse breeding conditions trigger colonisation events, if personal information plays a role in colonisation and if colonisers experience greater fitness. Our results show a temporal mismatch between colonisation events and both density-dependence and perturbations at the source colony, probably because colonisers needed a longer prospecting period to compensate for the lack of public information. Colonisers were mostly experienced individuals gaining higher breeding success in the new colony. Our results highlight the demographic value that experienced individuals can have on metapopulation dynamics of social longlived organisms., FPU (ref. FPU2012-000869), IBISES (ref. CGL2013- 42203-R) and MINOW (ref. H2020-634495)

Many chelonians have colourful dots, patches and stripes throughout their body that are made up, at least in part, of carotenoids. Therefore, turtles are very suitable models to study the evolution and functionality of carotenoid-based colouration. Recent studies suggested a close link between colouration and immune system in these taxa. However, more research is needed to understand the role of these colourful stripes and patches in turtle visual signalling. The purpose of this study was to explore the relationship between growth rate and colouration in European pond turtles. In particular, we wanted to answer the question of whether there is a trade-off between growth and colour expression. We also aimed to explore the effect of body size and age on colour variation. Turtles from a reintroduction-breeding program were recaptured, weighed and measured over an 8-year period to estimate their growth rates and age. We also measured with a spectrometer the reflectance of colour patches in two different body parts: shell and forelimb. We found that turtles with a faster growth rate had brighter limb stripes independently of their age. On the other hand, shell colouration was related to body size with larger turtles having brighter shell stripes and higher values of carotenoid chroma. Our results suggest that fast-growers may afford to express intense colourful limb stripes likely due to their higher intake of carotenoids that would modulate both growth and colour expression. However, shell colouration was related to body size probably due to ontogenetic differences in the diet, as juveniles are strictly carnivorous while adults are omnivorous. Alternatively, shell colouration might be involved in crypsis as the shell is visually exposed to predators.

OHBM2017 Symposium on multimodal functional cartography: from connectivity to cognition

Major landscape transformations have occurred in the northern Mediterranean over the last decades, including urbanization, agricultural intensification and land abandonment, which, in turn, increase the risk of the propagation of fire. We used repeated-count surveys conducted at 369 sites in France and Spain to jointly model the effects of environmental covariates on the abundance, occupancy and detection of Hermann’s tortoise, a long-lived and endangered species, using a novel zero-inflated approach. We also employed a large dataset of presence-only data collected in Provence to model environmental influences on occurrence probability using maximum entropy models. In both France and Spain, sites that experienced wildfires over the last 50 years hosted 31% fewer individuals than unburned sites. In Provence, higher wildfire frequency decreased this species’ occurrence probability, from 50% when 0–1 fire had occurred over the last 50 years, to 7% in areas that had burned at least 3 times. We also showed that abundance required a long recovery time (more than 25 years) after wildfires. In Provence, the highest occurrence probability for this species was found in patchy landscapes and scrub and/or herbaceous vegetation. The lowest species occurrence was found in extensive artificial areas, vineyards and arable lands. These results suggest a high risk of population extinction in the future if these types of habitats continue to expand in plains and coastal areas to the detriment of scrublands. Higher wildfire frequency predicted by climate change scenarios in the Mediterranean is also likely to increase the risk of extinction for some populations.

The network organization of the human brain varies across individuals, changes with development and aging, and differs in disease. Discovering the major dimensions along which this variability is displayed remains a central goal of both neuroscience and clinical medicine. Such efforts can be usefully framed within the context of the brain's modular network organization, which can be assessed quantitatively using powerful computational techniques and extended for the purposes of multi-scale analysis, dimensionality reduction, and biomarker generation. Though the concept of modularity and its utility in describing brain network organization is clear, principled methods for comparing multi-scale communities across individuals and time are surprisingly lacking. Here, we present a method that uses multi-layer networks to simultaneously discover the modular structure of many subjects at once. This method builds upon the well-known multi-layer modularity maximization technique, and provides a viable and principled tool for studying differences in network communities across individuals and within individuals across time. We test this method on two datasets and identify consistent patterns of inter-subject community variability, demonstrating that this variability – which would be undetectable using past approaches – is associated with measures of cognitive performance. In general, the multi-layer, multi-subject framework proposed here represents an advancement over current approaches by straighforwardly mapping community assignments across subjects and holds promise for future investigations of inter-subject community variation in clinical populations or as a result of task constraints.

Assessing population trends is a basic prerequisite to carrying out adequate conservation strategies. Selecting an appropriate method to monitor animal populations can be challenging, particularly for low-detection species such as reptiles. This study compares 3 detection-corrected abundance methods (capture–recapture, distance sampling, and N-mixture) used to assess population size of the threatened Hermann's tortoise. We used a single dataset of 432 adult tortoise observations collected at 118 sampling sites in the Plaine des Maures, southeastern France. We also used a dataset of 520 tortoise observations based on radiotelemetry data collected from 10 adult females to estimate and model the availability (g0) needed for distance sampling. We evaluated bias for N-mixture and capture–recapture, by using simulations based on different values of detection probabilities. Finally, we conducted a power analysis to estimate the ability of the 3 methods to detect changes in Hermann's tortoise abundances. The abundance estimations we obtained using distance sampling and N-mixture models were respectively 1.75 and 2.19 times less than those obtained using the capture–recapture method. Our results indicated that g0 was influenced by temperature variations and can differ for the same temperature on different days. Simulations showed that the N-mixture models provide unstable estimations for species with detection probabilities

Conditions during early life, including maternal cohort effects, can influence the future fitness of individuals. This may be particularly true for longdistance migrating birds, because, apart from conditions experienced by cohorts during rearing, conditions during early life in regions far from breeding grounds may also influence their population dynamics. Very little is known about the fitness consequences of those conditions experienced by juveniles after independence, especially in wild populations and for longlived birds. We used multi-event capture-recapture-recovery models and a unique 26-year dataset for the Audouin’s gull (Larus audouinii) to assess for the first time whether survival was influenced by early conditions, both during the rearing period (i.e. a maternal cohort effect potentially affected by density dependence) and the first winter (i.e. a cohort effect driven by climate when birds disperse to wintering grounds). Our results show that juvenile survivalwas highly sensitive to early-life conditions and that survival decreased with stronger density dependence and harsh climate. The two consecutive cohort effects were of similar magnitude and they may represent a selection filter. Thus, early-life conditions had a strong impact on survival, and neglecting this complexity may hinder our understanding on how populations of long-lived animals fluctuate and respond to perturbations.

The aim of this study was to determine the impact of priority and emerging Persistent Organic Pollutants (POPs) in gull eggs from two species, the scavenger Larus michahellis and the protected species, Larus audouinii. These two species share habitat in the Natural Park of the Ebro delta (Catalonia, Spain). Compounds studied are included or under consideration in the Stockholm Convention and comprise polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), organochlorinated compounds (OCs), perfluorinated compounds (PFCs) and short chain chlorinated paraffins (SCCPs). Four methods based in selective extraction and gas or liquid chromatography coupled to mass spectrometry were used and quality parameters are provided. OC pesticides and marker PCBs were the most abundant chemical families detected in eggs from the two species, followed by PFCs, PBDEs (especially BDE 209) and SCCPs. Dioxin-like PCBs and PCDD/Fs were also detected in all samples. The overall widespread presence of POPs is discussed in terms of feeding habits, bird ecology and anthropogenic pressures in the protected Ebro delta breeding area.