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Dispersal propensity has been correlated with personality traits, conspecific density and predation risk in a variety of species. Thus, changes in the relative frequency of behavioural phenotypes or in the ecological pressures faced by individuals in contrasting habitats can have unexpected effects on their dispersal strategies. Here, using the burrowing owl Athene cunicularia as a study model, we test whether changes in the behavioural profile of individuals and changes in conspecific density and predation pressure associated with urban life influence their breeding dispersal decisions compared to rural conspecifics. Our results show that breeding dispersal behaviour differs between rural and urban individuals. Site fidelity was lower among rural than among urban birds, and primarily related to an individual's behaviours (fear of humans), which has been reported to reflect individual personality. In contrast, the main determinant of site fidelity among urban owls was conspecific density. After taking the decision of dispersing, urban owls moved shorter distances than rural ones, with females dispersing farther than males. Our results support a personality-dependent dispersal pattern that might vary with predation risk. However, as multiple individuals of two populations (one urban, one rural) were used for this research, differences can thus also be caused by other factors differing between the two populations. Further research is needed to properly understand the ecological and evolutionary consequences of changes in dispersal behaviours, especially in terms of population structuring and gene flow between urban and rural populations.

Determining the non-breeding distribution and activity patterns of migratory animals is essential to understand the trade-offs across breeding, moulting and migratory periods and to evaluate the differential levels of exposure of these animals to threats throughout the year. By taking advantage of the current miniaturization of geolocators, during the breeding season of 2019, we deployed geolocators on 10 European Storm Petrels Hydrobates pelagicus breeding on Benidorm Island, Western Mediterranean, to determine the distribution and activity patterns of this small seabird species. Of the eight individuals that were recaptured with usable geolocation data, all individuals migrated to the North Atlantic Ocean, ranging between the Canary Islands and south of Iceland. They possibly take advantage of the more productive waters in the North Atlantic areas explored during the non-breeding period compared with the Western Mediterranean areas explored during the breeding period. This migratory pattern contrasted with the partial migration described for individuals breeding in the Central Mediterranean. Tracked individuals were more synchronous in their prenuptial than in their postnuptial migratory phenology, probably due to a higher probability of breeding success related to earlier arrival to the breeding area. At-sea activity data indicated that individuals spent more time on the water at night (and especially on those nights around the new moon) during the first half of the non-breeding period (matching the dates of the moulting period of the species). Although birds may begin to moult their feathers while breeding, some seemed to overlap the moulting period with the postnuptial migration. Our results show that multi-colony studies are needed to understand the drivers of distinct migratory patterns at intra- and inter-population levels and how small migratory species trade-off the overlap of moult with other energetically demanding activities such as breeding or migrating., This work was supported by the Welcome Pack (2019) of the Universitat de Barcelona and by the Spanish Ministerio de Ciencia e Inovación (project reference: PID2020-117155GB-I00 funded by MCIN/AEI/ 10.13039/501100011033). A.S.-A. and R.R. were supported by postdoctoral Ramón y Cajal contracts of the Spanish Ministerio de Economía, Industria y Competitividad (MINECO; RYC-2017-22055 and RYC-2017-22796).

Variation in offspring sex ratios is a central topic in animal demography and population dynamics. Most studies have focused on bird species with marked sexual dimorphism and multiple-nestling broods, where the offspring sex ratio is often biased due to different individual or environmental variables. However, biases in offspring sex ratios have been far less investigated in monomorphic and single-egg laying species, and few studies have evaluated long-term and large-scale variations in the sex ratio of nestling vultures. Here, we explore individual and environmental factors potentially affecting the secondary sex ratio of the monomorphic griffon vulture Gyps fulvus. We used information collected at three breeding nuclei from central Spain over a 30-year period (1990–2020) to analyse the effects of nestling age, parental age, breeding phenology, conspecific density, population reproductive parameters, and spatial and temporal variability on nestling sex. Sex ratio did not differ from parity either at the population or the nuclei level. No significant between-year differences were detected, even under highly changing conditions of food availability associated with the mad-cow crisis. We found that tree nesting breeders tend to have more sons than daughters, but as this nesting behavior is rare and we consequently have a small sample size, this issue would require additional examination. Whereas further research is needed to assess the potential effect of breeder identity on nestling sex ratio, this study contributes to understanding the basic ecology and population dynamics of Griffon Vultures, a long-lived species with deferred maturity and low fecundity, whose minor deviations in the offspring sex ratio might imply major changes at the population level., Research was funded by the Spanish Ministry of Economy, Industry, and Competitiveness through projects CGL2007-61395, CGL2010-15726, CGL2013-42451-P and PID2019-109685GB-I00 of the Spanish Ministry of Science and Innovation. G.G.L. was supported by a FPU fellowship of the Spanish Ministry of Science, Innovation and Universities (FPU19/06511). A.S.A. was supported by a Ramón y Cajal fellowship of the Spanish Ministry of Science (RYC-2017-22796).

Este artículo contiene 11 páginas, 3 figuras, 2 tablas. Dataset: https://digital.csic.es/handle/10261/161183, Early life conditions, especially in long-lived organisms, can have both immediate and long-lasting effects in vital traits generating demographic structure across cohorts. Multiple non-exclusive hypotheses have been proposed to explore this question. For instance, the silver spoon, the viability selection or the predictive adaptive response hypothesis, predict that long lasting effects resulting from harsh early conditions could be negative, positive or vary with current environmental conditions, respectively. We use an 18-year capture–mark–recapture dataset on adult Audouin’s gulls Ichthyaetus audouinii to test for these different hypotheses while accounting for age, breeding experience and large-scale dispersal. Audouin’s gull cohorts experiencing harsh conditions during early life (i.e. nestling period and first winter) are known to experience lower first year survival. Here, we show that early life conditions also explained a large proportion (54%) of adult survival variation among cohorts. However, adulthood cohorts experiencing poor early life conditions had higher adult survival, in accordance with the viability selection hypothesis. Our results also show that apparent inexperienced breeders showed lower survival than experienced ones. Moreover, adult survival decreased with age. These results could suggest an increased cost of reproduction for deferred breeders, individual quality differences or survival senescence in this population. Overall, our study highlights the importance of early development, age and breeding experience as potential factors generating heterogeneity of survival between cohorts. Understanding the mechanisms driving responses to early life conditions at different life stages is fundamental to understanding the long-term dynamics of wild populations., This work was funded through projects RESET (CGL2017-85210-P) and IBISES (ref. CGL2013-42203-R). APP was supported by a predoctoral fellowship of the Ministry of Education (FPU-AP 2012-0869). ASA was supported by a postdoctoral contract co-funded by the Regional Government of the Balearic Islands and the European Social Fund (ref. PD/003/2016) and by a Ramon y Cajal fellowship from the Spanish Ministry of Innovation and Universities, the Agencia Estatal de Investigación and the European Social Found (RYC-2017-22796).

Long-lived avian scavengers are threatened worldwide and thus, are common targets of conservation plans. However, scientific evidence of both the factors limiting populations and effectiveness of management actions are greatly needed in order to develop more efficient and successful conservation strategies. We assessed the effectiveness of conservation actions applied within a LIFE-Nature project aimed at improving the long-term survival of the critically endangered Canarian Egyptian vulture: including education campaigns for public awareness and control of illegal poisoning and the modification of power lines to reduce the risk of accidents. We formulated a multievent capture–mark–recapture model to obtain estimates of survival for juvenile, subadult and adult birds accounting for probabilities of resight, recovery and losses of metal and colour rings. Models supported a substantial enhancement in survival for subadult and adult birds and a moderate improvement for juveniles after the implementation of LIFE actions. Ring loss probabilities became notably high in the middle to long term. Poisoning events became very rare after LIFE was implemented, suggesting a positive effect of environmental education and awareness campaigns. Entanglements and collisions in power lines were also efficiently mitigated. Instead, electrocutions became the most identified cause of death in the post-LIFE stage. Synthesis and applications. Our results highlight the improvement of survival in a threatened island vulture population after the implementation of a European LIFE conservation project. On small islands, with small human populations and few stakeholders, education and awareness campaigns can be especially effective for biodiversity conservation. We also demonstrate the need to complement conservation programmes with long-term monitoring, which is essential to evaluate the effectiveness of actions, especially for long-lived species.

Dispersal propensity has been correlated with personality traits, conspecific density and predation risk in a variety of species. Thus, changes in the relative frequency of behavioural phenotypes or in the ecological pressures faced by individuals in contrasting habitats can have unexpected effects on their dispersal strategies. Here, using the burrowing owl Athene cunicularia as a study model, we test whether changes in the behavioural profile of individuals and changes in conspecific density and predation pressure associated with urban life influence their breeding dispersal decisions compared to rural conspecifics. Our results show that breeding dispersal behaviour differs between rural and urban individuals. Site fidelity was lower among rural than among urban birds, and primarily related to an individual’s behaviours (fear of humans), which has been reported to reflect individual personality. In contrast, the main determinant of site fidelity among urban owls was conspecific density. After taking the decision of dispersing, urban owls moved shorter distances than rural ones, with females dispersing farther than males. Our results support a personality-dependent dispersal pattern that might vary with predation risk. However, as multiple individuals of two populations (one urban, one rural) were used for this research, differences can thus also be caused by other factors differing between the two populations. Further research is needed to properly understand the ecological and evolutionary consequences of changes in dispersal behaviours, especially in terms of population structuring and gene flow between urban and rural populations.

Discards from fisheries are the most important predictable anthropogenic food subsidies (PAFS) that are being incorporated into marine ecosystems. Changes on their availability and predictability can help us to understand the role that food availability (i.e. an important indicator of the carrying capacity) plays at different ecological levels, from individual fitness to community dynamic and ecosystem functioning. For several reasons, seabirds are an excellent model for evaluating the ecological effects arising from a lack of discards: 1) they are one of the most important discard scavengers, 2) they are easy to monitor and 3) they are apical predators are globally distributed, which makes them suitable health indicators of ecosystems. Here we review the existing information on seabird-discard interactions to identify the main knowledge gaps and propose new challenges for improving our understanding of the general role of food availability. We conclude that the new policies on the ban of fishery discards that are being progressively implemented in the European Union, Norway, Chile and New Zealand offer a suitable experimental scenario for improving our understanding of how a large decrease in the carrying capacity may alter demographic parameters such as survival, dispersal and reproduction, the resilience of populations against perturbations and the role of individual specialization in the foraging process., Los descartes pesqueros constituyen el recurso antropogénico predecible (PAFS) más importante que está siendo incorporado en los ecosistemas marinos. Cambios en su disponibilidad y predictibilidad pueden ayudar a entender mejor el papel ecológico de la disponibilidad de alimento (i.e. un importante indicador de la capacidad de carga) a diferentes niveles, desde la eficacia biológica individual hasta la dinámica de poblaciones o el funcionamiento de los ecosistemas. Las aves marinas constituyen un modelo excelente para estudiar los efectos ecológicos derivados de la falta de descartes por diversas razones: las aves marinas: 1) se encuentran entre los principales carroñeros de descartes, 2) son fáciles de monitorear y 3) son depredadores apicales globalmente distribuidos, lo cual las convierte en buenas indicadoras de la salud del ecosistema. En el presente estudio revisamos la información existente sobre las interacciones ecológicas entre las aves marinas y los descartes de la pesca, con el fin de identificar los principales vacíos de conocimiento y plantear retos futuros de cara a mejorar nuestra comprensión sobre el papel ecológico que tiene la disponibilidad de alimento. Concluimos que las políticas actuales en materia de prohibición de descartes que están siendo implementadas en la Unión Europea, Noruega, Chile o Nueva Zelanda, ofrecen un escenario ideal para mejorar nuestra comprensión sobre cómo una reducción de la capacidad de carga puede alterar parámetros demográficos tales como la supervivencia, la dispersión y la reproducción, la resiliencia de las poblaciones frente a perturbaciones y el papel de la especialización individual en el proceso de forrajeo.

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In some vertebrate species, family units are typically formed when sexually mature individuals delay dispersal and independent breeding to remain as subordinates in a breeding group. This behaviour has been intensively studied in gregarious species but has also been described in non-social species where ecological and evolutionary drivers are less known. Here, we explore factors that favour delayed dispersal and family living and potential benefts associated with this strategy in a non-social, monogamous species (the burrowing owl, Athene cunicularia) occupying urban and rural habitats. Our results show that family units arise when frst-year individuals, mainly males, delay their dispersal to stay in their natal nests with their parents. This delayed dispersal, while still uncommon, was more prevalent in urban (7%) than in rural (3%) habitats, and in areas with high conspecifc density and productivity. Birds delaying dispersal contributed to the genetic pool of the ofspring in 25% of the families analysed, but did not increase the productivity of the nests where they remained. However, their presence was related to an improvement in the body condition of chicks, which was ultimately linked to a slightly positive efect in ofspring future survival probabilities. Finally, delayed dispersers were recruited as breeders in high-quality urban territories and closer to their natal nests than individuals dispersing during their frst year of life. Thus, our results suggest that delaying dispersal may be mainly related to opportunities to inheriting a good quality territory, especially for males. Our study contributes to understanding the role played by habitat quality in promoting delayed dispersal and family living, not only in social but also non-social species, highlighting its impact in the ecology and evolution of animal populations

Este artículo contiene 10 páginas, 4 figuras, 1 tabla., Stochasticity in food availability influences vital rates such as survival and fertility. Life-history theory predicts that in longlived organisms, survival should be buffered against environmental stochasticity showing little temporal variability. Furthermore, to optimize survival prospects, many animal species perform migrations to wintering areas where food availability is larger. Species with large latitudinal distribution ranges may show populations that migrate and others that are resident, and they may co-occur in winter. One example of these species is the predatory raptor buzzard Buteo buteo. Here, we test whether temporal variability in the density of five small mammal species of prey inhabiting different habitats (shrubland and forests) influences local annual survival of buzzards in a wintering area depending on their age and residency status (residents versus wintering individuals). We found that prey density explained a considerable amount of annual changes in local survival, which was higher for older and resident birds. This difference in local survival likely corresponded to philopatry to the wintering area, which was larger for residents and increased when prey density was larger. The total density of prey inhabiting open shrublands was the variable explaining more variance in temporal variability of local survival, even though the study area is mostly occupied by woodlands. Temporal population dynamics of the different small mammals inhabiting shrublands were not synchronous, which suggests that buzzards preyed opportunistically on the most abundant prey each winter. Generalist predation may buffer the impact of resource unpredictability for pulsed and asynchronous prey dynamics, typical of small mammals in winter., Funding Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Regional conservation agencies (Diputació de Barcelona, Dept. de Territori i Sostenibilitat -Generalitat de Catalunya) provided financial support to SEMICE. JG funded on his own all fieldwork research on buzzards. ASA was supported by a Ramón y Cajal fellowship of the Spanish Ministry of Science (RYC-2017-22796).

Events of non-natural mortality in human-dominated landscapes are especially challenging for populations of large vertebrates with K strategies. Among birds, vultures are one of the most threatened groups experiencing sharp population declines due to non-natural mortality. Factors causing non-natural mortality are usually studied separately. However, the potential use of an integrated index able to predict large-scale mortality risks of avian scavengers could be especially useful for planning conservation strategies. Here, we used the Human Footprint index to examine the impact of landscape anthropization on the survival rates of 66 GPS-tagged adult Eurasian griffon vultures (Gyps fulvus) in two Spanish regions. Foraging in more anthropized areas resulted in a significantly higher individual mortality risk mainly due to collisions with vehicles, poisonings, electrocutions and fatalities with wind turbines. Mean yearly survival rates were estimated at 0.817 ± 0.043 SE and 0.968 ± 0.018 SE for individuals from the more and less anthropized regions, respectively. Additional research should investigate whether some vulture populations could be acting as sinks unnoticed due to metapopulation dynamics. From a broader point of view, our study shows that a straightforward Human Footprint was a useful index to predict the survival of top scavengers and can be highly applicable to planning large-scale conservation measures., This research was funded by the Project RNM-1925 (Junta de Andalucía), the Project CGL2015-66966-C2-1-2-R (Spanish Ministry of Economy and Competitiveness and EU/ERDF) and the Project RTI2018-099609-B-C21 (Spanish Ministry of Economy and Competitiveness and EU/ERDF). “Roads Less Travelled” project (DiversEarth, Trashumancia y Naturaleza and Yolda Initiative) also contributed to this research. EA was supported by La Caixa-Severo Ochoa International PhD Program 2015. ASA and ACA by a post-doctoral contract Viçent Mut (PD/003/2016 and PD/039/2017, respectiely) co-funded by the Govern Balear and European Social Funds. ASA was also supported by a Spanish Ramón y Cajal contract (RYC-2017-22796) funded by the Ministerio de Ciencia, Innovación y Universidades, the Agencia Estatal de Investigación and the European Social Found. JMPG was supported by a Juan de la Cierva research contract (FJCI-2015-25632).

Mate searching is a key component of sexual reproduction that can have important implications for population viability, especially for the mate‐finding Allee effect. Interannual sperm storage by females may be an adaptation that potentially attenuates mate limitation, but the demographic consequences of this functional trait have not been studied. Our goal is to assess the effect of female sperm storage durability on the strength of the mate‐finding Allee effect and the viability of populations subject to low population density and habitat alteration. We used an individual‐based simulation model that incorporates realistic representations of the demographic and spatial processes of our model species, the spur‐thighed tortoise (Testudo graeca). This allowed for a detailed assessment of reproductive rates, population growth rates, and extinction probabilities. We also studied the relationship between the number of reproductive males and the reproductive rates for scenarios combining different levels of sperm storage durability, initial population density, and landscape alteration. Our results showed that simulated populations parameterized with the field‐observed demographic rates collapsed for short sperm storage durability, but were viable for a durability of one year or longer. In contrast, the simulated populations with a low initial density were only viable in human‐altered landscapes for sperm storage durability of 4 years. We find that sperm storage is an effective mechanism that can reduce the strength of the mate‐finding Allee effect and contribute to the persistence of low‐density populations. Our study highlights the key role of sperm storage in the dynamics of species with limited movement ability to facilitate reproduction in patchy landscapes or during population expansion. This study represents the first quantification of the effect of sperm storage durability on population dynamics in different landscapes and population scenarios., We find that sperm storage is an effective mechanism that can reduce the strength of the mate‐finding Allee effect and contribute to the persistence of low‐density populations, especially in altered landscapes. Our study represents the first quantification of the effect of sperm storage durability on population dynamics in different landscapes and population scenarios.

A common complication in invasive pest management is that the infectious state of the host can be wrongly assessed, leading to biases in the estimation of the prevalence of the pest and on the efficacy of mitigation actions. We designed a multievent model that accommodates uncertainty on host state to investigate the dynamics of the infestation of Phoenix canariensis by the invasive Rhynchophorus ferrugineus. Since 2011, the council of Palma city (Mallorca Island, Spain) applied preventive, curative and destructive treatments to public Phoenix palms. A year later awareness campaigns focused on every palm owner in an attempt to control the plague. We estimated the probability of infestation and assessed the efficiency of mitigation measures, awareness campaigns and palm-dependent covariates. Our results show that infestation probabilities were higher for palms infested in the previous year than for healthy palms and it decreased substantially over time as a results of mitigation measures and awareness campaigns. Palms surrounded by treated palms had a lower probability of being infested than palms surrounded by untreated palms, i.e. private palms before awareness campaigns implementation. Our results highlight the key role of awareness campaigns and public participation for invasive species control., A.S.A. was supported by a ‘Vicenç Mut’ contract co-funded by the Regional Government of the Balearic Islands and the European Social Fund (PD/003/2016) and a Ramón y Cajal contract (RYC-2017- 22796) funded by the Ministerio de Ciencia, Innovación y Universidades, the Agencia Estatal de Investigación and the European Social Found (“El Fondo Social Europeo invierte en tu futuro”).

The Asian tiger mosquito, Aedes albopictus (Diptera: Culicidae), is a highly invasive species and a vector of several viruses of serious concern to public health. Investigating the habitat selection of this species at small to medium scales is essential to the planning of effective prevention and control campaigns. The present group considered detailed data for this species' presence/absence collected at 228 sites on Mallorca Island (Spain) in autumn 2015, 3 years after the first detection of the species on the island. Site occupancy models accounting for false negative detections and imperfect monitoring were used to evaluate the relationships between mosquito presence and habitat variables. In the study area, mosquito presence was negatively associated with altitude, probably as a result of greater human presence at low altitudes near the coast. Moreover, the presence of Ae. albopictus was positively associated with swimming pools as a result of associated gardens, plants and sources of fresh water. These two variables were combined to predict the presence of the species across the entire island.

The nominate race of the greater crested tern Thalasseus bergii breeds only along the coast of the Benguela region (west coast) of southern Africa, where its population is increasing, in contrast t...

Este artículo contiene 7 páginas, 3 figuras., Predators are an important ecological and evolutionary force shaping prey population dynamics. Ecologists have extensively assessed the lethal effects of invasive predators on prey populations. However, the role of non-lethal effects, such as physiological stress or behavioural responses like dispersal, has been comparatively overlooked and their potential population effects remain obscure. Over the last 23 years, we developed a mark-recapture program for the Audouin’s gull and an intensive carnivore monitoring program to assess how the appearance and invasion of the study site by carnivores affects population dynamics. We evaluate changes in turnover of discrete breeding patches within the colony, age structure and breeding performance. Once carnivores entered the colony, the number of occupied patches increased, indicating a higher patch turnover. Breeders responded by moving to areas less accessible to carnivores. More importantly, the presence of carnivores caused differential (and density-independent) breeding dispersal: experienced, better-performing breeders were more likely to leave the colony than younger breeders. This differential dispersal modified the age structure and reduced the reproductive performance of the population. Our results confirm the importance experience in the study of populations. The role of differential dispersal for animal population dynamics might be more important than previously thought, especially under scenarios of global change., RESET (ref.CGL2017-85210-P), FPU (ref. FPU2012-000869), IBISES (ref. CGL2013-42203-R) and MINOW (ref. H2020- 634495). ASA and MG are supported by a postdoctoral contract co-funded by the Regional Government of the Balearic Islands and the European Social Fund (ref. PD/003/2016 and PD/023/2015).

Este artículo contiene 14 páginas, 5 tablas, 5 figuras, 2 apéndices., Life-history traits of migratory seabirds are influenced by changing conditions at breeding and wintering grounds. Climatic conditions and predation are known to impact populations’ survival rates, but few studies examine their effect simultaneously. We used multievent capture–recapture models to assess mortality due to environmental conditions and predation in breeding European storm petrels (Hydrobates pelagicus) in two allopatric colonies (Mediterranean and Atlantic). Predatory mortality at the colonies showed annual variation, being around 0.05 in certain years. Mortality at sea differed between the two oceanic basins, and was lower in the Mediterranean colony [0.11, 95% CI (0.09, 0.14)] when compared to the Atlantic colony [0.18, 95% CI (0.15, 0.22)]. The Western Mediterranean Oscillation index (WeMOi) explained 57% of the temporal variability in mortality of Mediterranean breeders. In comparison, 43% of the temporal variability in mortality of Atlantic breeders was explained by the winter St Helena index (wHIX) and El Niño-Southern Oscillation index (wENSO). Our results suggest that Mediterranean breeders remain in this basin for wintering where they may face lower migratory costs and more favourable environmental conditions. In contrast, Atlantic breeders’ mortality may be due to higher cost of migration, changing upwelling conditions in the Benguela current and heavy storms over their migratory route during La Niña events. This study underlines the importance of modelling separately different causes of mortality when testing the effects of climatic covariates., The study on Enez Kreiz was conducted with financial support of the Conseil Départemental du Finistère, the DREAL Bretagne—Ministry of environment, the MPAs Agency—Iroise National Marine Park and the Conseil Régional de Bretagne. Furthermore, we are indebted to Environmental Monitoring Service of Benidorm Island (Natural Park Serra Gelada-Generalitat Valenciana).

Survival is a key parameter in species' management and conservation. Most methods for estimating survival require time series data, large sample sizes and, overall, costly monitoring efforts. Inverse modeling approaches can be less data hungry, however they are underused in conservation sciences. Here we present an inverse modeling approach for estimating relative survival rates of long-lived species that is mathematically straightforward and evaluate its performance under constraints common in conservation studies related to small sample sizes. Specifically, we (i) estimated the relative survival rates in a Testudo graeca population based on one-year monitoring, (ii) assessed the impact of sample size on the accuracy, and (iii) tested alternative hypotheses on the impact of fire on the survival rates. We then compared the results of our approach with capture-recapture (CRC) estimates based on long-term monitoring. Our approach (153 individuals within a single year) yielded estimates of survival rates overlapping those of CRC estimates (11 years of data and 1009 individuals) for adults and subadults, but not for juveniles. Simulation experiments showed that our method provides robust estimates if sample size is above 100 individuals. The best models describing the impact of fire on survival identified by our approach predicts a decrease in survival especially in hatchlings and juvenile individuals, similar to CRC estimates. Our work proves that inverse modeling can decrease the cost for estimating demographic rates, especially for long-lived species and as such, its use should be encouraged in conservation and management sciences., The Spanish Ministry of Science and European Regional Development Fund funded this work through Projects CGL2012-33536 and CGL2015-64144-R; MINECIO/FEDER). RCRC was supported by the Regional Government of the Community of Valencia (ACIF/2010/ 133). ASA was supported by a Ramón y Cajal contract (RYC-2017-22796) co-funded by the Spanish Ministry of Science, the Agencia Estatal de Investigación and the European Social Fund. KvB was supported by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - Projektnummer 316099922 - TRR 212.

There is a growing need to understand how species respond to habitat changes and the potential key role played by natal dispersal in population dynamics, structure and gene flow. However, few studies have explored differences in this process between conspecifics living in natural habitats and those inhabiting landscapes highly transformed by humans, such as cities. Here, we investigate how individual traits and social characteristics can influence the natal dispersal decisions of burrowing owls (Athene cunicularia) living in urban and rural areas, as well as the consequences in terms of reproductive success and apparent survival. We found short dispersal movements among individuals, with differences between urban and rural birds (i.e., the former covering shorter distances than the latter), maybe because of the higher conspecific density of urban compared to rural areas. Moreover, we found that urban and rural females as well as bold individuals (i.e., individuals with shorter flight initiation distance) exhibited longer dispersal distances than their counterparts. These dispersal decisions have effects on individual fitness. Individuals traveling longer distances increased their reproductive prospects (productivity during the first breeding attempt, and long term productivity). However, the apparent survival of females decreased when they dispersed farther from their natal territory. Although further research is needed to properly understand the ecological and evolutionary consequences of dispersal patterns in transformed habitats, our results provide information about the drivers and the consequences of the restricted natal movements of this species, which may explain its population structuring through restricted gene flow between and within urban and rural areas.

Ticks can negatively affect their host by direct effects as blood feeding causing anaemia or discomfort, or by pathogen transmission. Consequently, ticks can have an important role in the population dynamics of their hosts. However, specific studies on the demographic effects of tick infestation on seabirds are still scarce. Seabird ticks have also the potential to be responsible for the circulation of little known tick-borne agents, which could have implications for non-seabird species. Here, we report the results of investigations on potential associations between soft tick Ornithodoros maritimus load and reproductive parameters of storm petrels Hydrobates pelagicus breeding in a large colony in a cave of Espartar Island, in the Balearic archipelago. We also investigated by molecular analyses the potential viral and bacterial pathogens associated with O. maritimus ticks present at the colony. Lower nestling survival was recorded in the most infested area, deep in the cave, compared to the area near the entrance. The parasite load was negatively associated with the body condition of the nestlings. One pool of ticks tested positive for West Nile virus and 4 pools tested positive for a Borrelia species which was determined by targeted nested PCR to have a 99% sequence identity with B. turicatae, a relapsing fever Borrelia. Overall, these results show that further investigations are needed to better understand the ecology and epidemiology of the interactions between ticks, pathogens and Procellariiform species., This Project was partially funded by the Govern Balear (Acciones Especiales, AAEE031/2017) and the Spanish Ministry of Innovation and Universities (RESET, ref: CGL2017-85210-P). ASA was funded by the Spanish Ministry of Innovation and Universities Innovation and Universities, the Agencia Estatal de Investigación and the European Social Found (RYC-2017- 22796).

Bird migration studies have been given added impetus recently thanks to the miniaturisation of tracking devices. However, tracking methodologies have remained impractical for the smallest pelagic species and so important gaps in knowledge still exist. In the case of the European Storm-petrel Hydrobates pelagicus, while Atlantic populations are thought to overwinter along the south-western African coast, the winter quarters of Mediterranean birds remain more enigmatic. We performed stable isotope analysis (SIA) of C and N on P1, S8 and P10 feathers from 33 adult birds captured in three Atlantic colonies and 156 adult birds in seven western Mediterranean colonies to infer their wintering areas. In addition, we collated all observational field data, both from peer-reviewed publications and the wider literature, to complement our inferences from SIA. Within the Atlantic, isotopic profiles of feathers moulted at the breeding grounds (P1) differed between birds captured at northern Atlantic and Canary Islands colonies, but were similar for feathers moulted in winter quarters (S8 and P10), indicating low migratory connectivity. Isotopic values of feathers from western Mediterranean birds differed from those of Atlantic birds and showed Mediterranean values for all feathers, indicating that the former overwinter in Mediterranean waters. Variance in the isotopic values was greater in winter than in breeding season feathers, suggesting that birds disperse over larger areas in winter. Isotopic values of feathers moulted during the non-breeding period could match a post-breeding movement towards the southern and eastern Mediterranean. This inference matches the distribution of the few winter reports, which are mainly concentrated in the south-central Mediterranean, mostly in the Tunisian Platform. Our results suggest that this region is the principal wintering area of Mediterranean Storm-petrels.-Martínez, C., Roscales, J.L., Sanz-Aguilar, A. & González-Solís, J. (2019). Inferring the wintering distribution of the Mediterranean populations of European Storm-petrels Hydrobates pelagicus melitensis from stable isotope analysis and observational field data., Financial support was provided by the Ministerio de Ciencia e Innovación (CGL2009-11278/BOS), Ministerio de Economía y Competitividad (CGL2013-42585-P and CGL2013-42203-R), Conselleria d’Agricultura, Medi Ambient i Territori des Illes Balears and Fondos FEDER.

Demographic parameters in wild populations are expected to be shaped by individual covariates and environmental variability. Thus, the understanding of the effects of age and/or environmental conditions on variability in vital rates is of special importance in ecological and evolutionary studies. Early age-related improvements in survival and reproduction and later declines due to senescence are expected, above all in long-lived species. Survival in these species is predicted to be a more conservative parameter than reproduction, thereby giving rise to less temporal variability. We studied age-dependent patterns of survival and breeding success in a long-lived seabird, the Mediterranean Storm Petrel Hydrobates pelagicus melitensis, and the additive influence of individual heterogeneity and environmental climatic variables using 22 years of individual-based data (1993–2014). The North Atlantic Oscillation index (NAO) and sea surface temperature (SST) were selected as proxies of environmental conditions in both breeding and wintering areas. Our results show that vital rates improved with age for both survival and breeding success. A slow effect of senescence at older ages was detected for breeding success, whereas models did not disentangle the occurrence or the absence of actuarial senescence. Reproduction was also influenced by the age of first observed reproduction: at the same age, more experienced birds that recruited earlier had a higher breeding success than less experienced ones. Breeding success (but not survival) also showed great temporal variability in accordance with theoretical predictions. Neither the NAO nor the SST explained this variability, probably because petrels feed on lower trophic levels than most pelagic seabirds and other physical features such as river runoffs and winds may be involved, as well as other environmental stressors such as predation by sympatric gulls.

In evolutionary and ecological studies, demographic parameters are commonly derived from detailed information collected on a limited number of individuals or in a confined sector of the breeding area. This partial monitoring is expected to underestimate survival and recruitment processes because individuals marked in a monitored location may move to or recruit in an unobservable site. We formulate a multi-event capture-recapture model using E-SURGE software which incorporates additional information on breeding dispersal and the proportion of monitored sites to obtain unbiased estimates of survival and recruitment rates. Using simulated data, we assessed the biases in recruitment, survival and population growth rate when monitoring 10-90% of the whole population in a short- and a long-lived species with low breeding dispersal. Finally, we illustrate the approach using real data from a long-term monitoring program of a colony of Scopoli's shearwaters Calonectris diomedea. We found that demographic parameters estimated without considering the proportion of the area monitored were generally underestimated. These biases caused a substantial error in the estimated population growth rate, especially when a low proportion of breeding individuals were monitored. The proposed capture-recapture model successfully corrected for partial monitoring and provided robust demographic estimates. Synthesis and applications. In many cases, animal breeding populations can only be monitored partially. Consequently, recruitment and immature survival are underestimated, but the extent of these biases depends on the proportion of the area that remains undetected and the degree of breeding dispersal. We present a new method to obtain robust and unbiased measures of survival and recruitment processes from capture-recapture data. The method can be applied to any monitored population regardless of the type of nests (e.g. artificial or natural) or breeding system (e.g. colonial or territorial animals), and it only relies on an estimate of the proportion of the monitored area. The unbiased estimates obtained by this method can be used to improve the reliability of predictions of demographic population models for species' conservation and management., Research funds were provided by the Spanish Ministries of Science, Economy and Competitiveness (refs. BOS2003-01960, CGL2006-04325/BOS, CGL2009-08298, CGL2013-42203-R, JCI-2011-09085)

Identifying important foraging areas is fundamental to detecting the demographic drivers of a species and ultimately to plan conservation measures. For some species, such as small pelagic seabirds, foraging grounds are difficult to locate and remain largely unknown. We used miniaturised GPS devices (∼0.95g) to study foraging movements of Mediterranean Storm-petrels Hydrobates pelagicus melitensis during the incubation period. A total of 43 individuals at Benidorm colony (southwestern Mediterranean Sea) were tracked during a single foraging trip. We first assessed potential negative effects of the tracking devices. We recorded 22 complete foraging trips and measured home-range, foraging areas and the degree of overlap among individuals. We used first passage time analyses (FPT) to differentiate foraging/resting from flying/travelling activities and to infer potential foraging areas. All tracked birds returned to the colony. On average, individual body weight slightly decreased after foraging trips, suggesting a small immediate negative effect of the device. Tracked birds had high breeding success (0.71). Foraging trips lasted between 1 and 4.5 days with the total distance travelled ranging between 303.14 and 1,726.53km. The visited areas covered the whole south-western part of the Mediterranean Sea. Tracked individuals shared more than 50% of their home-range areas. Foraging areas were located further from the colony than previously thought (from 240 to 469km away) on deep sea areas of the Alboran Sea and Cartagena Canyons. Further studies are needed to locate foraging grounds during other life-cycle periods and to evaluate repeatability yearly, in order to determine the important marine areas for the species.—Rotger, A., Sola, A., Tavecchia, G. & Sanz-Aguilar, A. (2021). Foraging far from home: GPS-tracking of Mediterranean Storm-petrels Hydrobates pelagicus melitensis reveals long-distance foraging movements. Ardeola, 68: 3-16., Funds were provided by the project CNME19/0301/39 from the Generalitat Valenciana and the project CGL2017-85210-P from the Spanish Minister of Science, Innovation and Universities. ASA was supported by a “Ramon y Cajal” fellowship (RYC-2017-22796) and GT was supported by I. Hendriks.

Technological advances such as camera traps, and citizen science, coupled with advanced quantitative approaches, can help fill existing knowledge gaps and aid effective conservation. We combine citizen and camera trap observations to estimate survival of the Endangered lappet-faced vulture, assess the relative contribution of data from camera traps and citizens, as well as impact of loss of individual marks (wing tags), on survival estimates. We used data from 762 lappet-faced vultures wing tagged as nestlings during 2006–2017 in western Namibia. Observations of wing tagged individuals were provided by citizens or via camera traps. We formulated a multievent capture-mark-recapture model to estimate survival while accounting for probabilities of resighting by citizens and/or camera traps, recovery of dead individuals, and loss of the wing tag. Survival was relatively high for juveniles (0.79), and increased with age to 0.95. Citizen observations of live and dead birds were low in number. However, when combined with camera trap resightings of live individuals, citizen observations increased the precision of survival estimates of birds older than one year compared to using data from either sources separately. Wing tag loss was high after 5–6 years of tag age. If neglected, tag loss can result in severe underestimation of survival of the older age classes. Overall, we show that filling ecological knowledge gaps is possible through the efficient use of data provided by different sources, and by applying state-of the art approaches that minimise potential biases, such as those due to tag loss., AS thanks Academy of Finland (grant n. 307909). VMP was funded by Academy of Finland (278759) and the Finnish Cultural Foundation. ASA was supported by a Ramón y Cajal contract (RYC-2017-22796) funded by the Spanish Ministerio de Ciencia, Innovación y Universidades, the Agencia Estatal de Investigación and the European Social Fund.

Many species only show sexual dimorphism at the age of maturity, such that juveniles typically resemble females. Under these circumstances, estimating accurate age-specific demographic parameters is challenging. Here, we propose a multievent model parameterization able to estimate age-dependent survival using capture–recapture data with uncertainty in age and sex assignment of individuals. We illustrate this modeling approach with capture–recapture data from the ring-necked parakeet Psittacula krameri. We analyzed capture, recapture, and resighting data (439 recaptures/resightings) of 156 ring-necked parakeets tagged with neck collars in Barcelona city from 2003 to 2016 to estimate the juvenile and adult survival rate. Our models successfully estimated the survival probabilities of the different age classes considered. Survival probability was similar between adults (0.83, 95% CI = 0.77–0.87) and juveniles during their second (0.79, 95% CI = 0.58–0.87) and third winter (0.83, 95% CI = 0.65–0.88). The youngest juveniles (1st winter) showed a slightly lower survival (0.57, 95% CI = 0.37–0.79). Among adults, females showed a slightly higher survival than males (0.87, 95% CI = 0.78–0.93; and 0.80, 95% CI = 0.73–0.86, respectively). These high survival figures predict high population persistence in this species and urge management policies. The analysis also stresses the usefulness of multievent models to estimate juvenile survival when age cannot be fully ascertained., The present study was funded by CGL‐2016‐79568‐C3‐3‐P research project to JCS from the Spanish Research Council (Ministry of Economics and Competitiveness). ASA was supported by a postdoctoral contract cofunded by the Regional Government of the Balearic Islands and the European Social Fund (ref. PD/003/2016). Rings were provided by the Catalan Ringing Office (ICO). We also wish to acknowledge the support provided by COST European Cooperation in Science and Technology Actions ES1304 “ParrotNet” for the development of this manuscript.

Reproductive timing in many taxa plays a key role in determining breeding productivity , and is often sensitive to climatic conditions . Current climate change may alter the timing of breeding at different rates across trophic levels, potentially resulting in temporal mismatch between the resource requirements of predators and their prey . This is of particular concern for highertrophic-level organisms, whose longer generation times confer a lower rate of evolutionary rescue than primary producers or consumers. However, the disconnection between studies of ecological change in marine systems makes it difficult to detect general changes in the timing of reproduction5 . Here, we use a comprehensive meta-analysis of 209 phenological time series from 145 breeding populations to show that, on average, seabird populations worldwide have not adjusted their breeding seasons over time (−0.020 days yr−1 ) or in response to sea surface temperature (SST) (−0.272 days °C−1 ) between 1952 and 2015. However, marked between-year variation in timing observed in resident species and some Pelecaniformes and Suliformes (cormorants, gannets and boobies) may imply that timing, in some cases, is affected by unmeasured environmental conditions. This limited temperature-mediated plasticity of reproductive timing in seabirds potentially makes these top predators highly vulnerable to future mismatch with lower-trophic-level resources Fil: Keogan, Katharine. University of Edinburgh; Reino Unido Fil: Daunt, Francis. Centre for Ecology & Hydrology; Reino Unido Fil: Wanless, Sarah. Centre for Ecology & Hydrology; Reino Unido Fil: Phillips, Richard A.. British Antarctic Survey; Reino Unido Fil: Walling, Craig A.. University of Edinburgh; Reino Unido Fil: Agnew, Philippa. Oamaru Blue Penguin Colony; . Oamaru Blue Penguin Colony; Nueva Zelanda Fil: Ainley, David G.. HT Harvey and Associates; Estados Unidos Fil: Anker-Nilssen, Tycho. Norwegian Institute For Nature Research; Noruega Fil: Ballard, Grant. Point Blue Conservation Science; Estados Unidos Fil: Barrett, Robert T.. Uit The Arctic University Of Norway; Noruega Fil: Barton, Kerry J.. Landcare Research; Nueva Zelanda Fil: Bech, Claus. Norges Teknisk-naturvitenskapelige Universitet; Noruega Fil: Becker, Peter. Institut Fur Vogelforschung "vogelwarte Helgoland"; Alemania Fil: Berglund, Per-Arvid. University of Agricultural Sciences. Institute of Marine Research, Department of Aquatic Resources; Suecia Fil: Bollache, Loïc. Universite de Bourgogne; Francia Fil: Bond, Alexander L.. Memorial University Of Newfoundland; Canadá Fil: Bouwhuis, Sandra. Institut Fur Vogelforschung "vogelwarte Helgoland"; Alemania Fil: Bradley, Russell W.. Point Blue Conservation Science; Estados Unidos Fil: Burr, Zofia M.. The University Centre In Svalbard; Noruega Fil: Camphuysen, Kees. University of Utrecht; Países Bajos Fil: Catry, Paulo. Ispa - Instituto Universitário; Portugal Fil: Chiaradia, Andre. Monash University; Australia. Phillip Island Nature Park; Australia Fil: Christensen-Dalsgaard, Signe. Norwegian Institute for Nature Research; Noruega Fil: Cuthbert, Richard. Royal Society For The Protection Of Birds; Reino Unido Fil: Dehnhard, Nina. Universiteit Antwerp; Bélgica Fil: Descamps, Sébastien. Norwegian Polar Institute; Noruega Fil: Diamond, Tony. University Of New Brunswick; Canadá Fil: Divoky, George. Friends of Cooper Island; Estados Unidos Fil: Drummond, Hugh. Universidad Nacional Autónoma de México; México Fil: Dugger, Katie M.. United States Geological Survey; Estados Unidos Fil: Dunn, Michael J.. British Antarctic Survey; Reino Unido Fil: Emmerson, Louise. Australian Antarctic Division; Australia Fil: Erikstad, Kjell Einar. Norwegian Polar Institute; Noruega Fil: Fort, Jérôme. Université de la Rochelle; Francia Fil: Fraser, William. Polar Oceans Research Group; Estados Unidos Fil: Genovart, Meritxell. Consejo Superior de Investigaciones Cientificas. Instituto Mediterraneo de Estudios Avanzados; España Fil: Gilg, Olivier. Universite de Bourgogne; Francia. Groupe de Recherches En Ecologie Arctique; Fil: González-Solís, Jacob. Universidad de Barcelona; España Fil: Granadeiro, José Pedro. Universidade de Lisboa; Portugal Fil: Grémillet, David. University Of Cape Town; Sudáfrica Fil: Hansen, Jannik. University Aarhus; Dinamarca Fil: Hanssen, Sveinn A.. Norwegian Institute For Nature Research; Noruega Fil: Harris, Mike. Centre for Ecology & Hydrology; Reino Unido Fil: Hedd, April. Environment Canada; Canadá Fil: Hinke, Jefferson. National Oceanic And Atmospheric Administration; Estados Unidos Fil: Igual, José Manuel. Consejo Superior de Investigaciones Cientificas. Instituto Mediterraneo de Estudios Avanzados; España Fil: Jahncke, Jaime. Point Blue Conservation Science; Estados Unidos Fil: Jones, Ian. Memorial University Of Newfoundland; Canadá Fil: Kappes, Peter J.. Oregon Cooperative Fish And Wildlife Research Unit; Estados Unidos Fil: Lang, Johannes. Groupe de Recherche en Ecologie Arctique; Francia Fil: Langset, Magdalene. Norwegian Institute For Nature Research; Noruega Fil: Lescroël, Amélie. Géosciences Montpellier; Francia Fil: Lorentsen, Svein-Håkon. Norwegian Institute For Nature Research; Noruega Fil: Lyver, Phil O'B.. Landcare Research; Nueva Zelanda Fil: Mallory, Mark. Acadia University; Canadá Fil: Moe, Børge. Norwegian Institute For Nature Research; Noruega Fil: Montevecchi, William A.. Memorial University Of Newfoundland; Canadá Fil: Monticelli, David. University Of Coimbra, Marine And Environmental Sciences Center; Portugal Fil: Mostello, Carolyn. Massachusetts Division Of Fisheries And Wildlife; Estados Unidos Fil: Newell, Mark. Centre for Ecology & Hydrology; Reino Unido Fil: Nicholson, Lisa. Halfmoon Biosciences; Australia Fil: Nisbet, Ian. I. C. T. Nisbet & Company; Estados Unidos Fil: Olsson, Olof. Stockholms Universitet; Suecia Fil: Oro, Daniel. Consejo Superior de Investigaciones Cientificas. Instituto Mediterraneo de Estudios Avanzados; España Fil: Pattison, Vivian. Laskeek Bay Conservation Society; Canadá Fil: Poisbleau, Maud. Universiteit Antwerp; Bélgica Fil: Pyk, Tanya. Deakin University; Australia Fil: Quintana, Flavio Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Ramos, Jaime A.. University Of Coimbra, Marine And Environmental Sciences Center; Portugal Fil: Ramos, Raül. Universidad de Barcelona; España Fil: Reiertsen, Tone Kirstin. Norwegian Polar Institute; Noruega Fil: Rodríguez, Cristina. Universidad Nacional Autónoma de México; México Fil: Ryan, Peter. University Of Cape Town; Sudáfrica Fil: Sanz-Aguilar, Ana. Consejo Superior de Investigaciones Cientificas. Instituto Mediterraneo de Estudios Avanzados; España Fil: Schmidt, Niels M.. University Aarhus; Dinamarca Fil: Shannon, Paula. National Audubon Society Seabird Restoration Program; Estados Unidos Fil: Sittler, Benoit. Groupe de Recherche en Ecologie Arctique; Francia Fil: Southwell, Colin. Australian Antarctic Division; Australia Fil: Surman, Christopher. Halfmoon Biosciences; Australia Fil: Svagelj, Walter Sergio. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina Fil: Trivelpiece, Wayne. Bolinas; Estados Unidos Fil: Warzybok, Pete. Point Blue Conservation Science; Estados Unidos Fil: Watanuki, Yutaka. Hokkaido University; Japón Fil: Weimerskirch, Henri. Centre National de la Recherche Scientifique; Francia Fil: Wilson, Peter R.. Landcare Research; Nueva Zelanda Fil: Wood, Andrew G.. British Antarctic Survey; Reino Unido Fil: Phillimore, Albert B.. University of Edinburgh; Reino Unido Fil: Lewis, Sue. University of Edinburgh; Reino Unido

Invasive species face new environmental conditions in their areas of introduction. A correct timing of reproduction is crucial for the successful adjustment of individuals to their environments, yet the temporal aspects of the niche are a neglected subject in the study of biological invasions. When introduced, exotic species could successfully invade new habitats by making use of ecological opportunities, e.g. empty temporal Eltonian niches. Specifically, they may achieve this via conservatism of their native reproductive phenology and/or via plasticity in their reproductive timing. Here we compare the reproductive phenology of a marshland passerine community composed of five successfully established tropical exotic species and twelve coexisting Mediterranean native species along four consecutive years. Both groups showed large differences in their phenology, with exotics reproducing along more months and later in the year than natives. One exotic species even breeds only in late summer and early autumn, when virtually all natives have ceased breeding and when overall bird abundance as well as primary production in cultivated areas (rice fields) were highest. Nonetheless, estimates of population sizes and juvenile survival rates in the study area suggest that late breeding is not maladaptive but instead highly successful. The striking difference in reproductive timing suggests that the exotics may be taking advantage of a vacant Eltonian temporal niche, possibly generated by high resource availability in human-transformed habitats (rice fields and other croplands) in the study area. This study highlights the need to also consider the temporal aspects of the niche when studying invasions.

Large body-sized avian scavengers, including the Egyptian vulture (Neophron percnopterus), are globally threatened due to human-related mortality so guidelines quantifying the efficacy of different management approaches are urgently needed. We used 14. years of territory and individual-based data on a small and geographically isolated Spanish population to estimate survival, recruitment and breeding success. We then forecasted their population viability under current vital rates and under management scenarios that mitigated the main sources of non-natural mortality at breeding grounds (fatalities from wind farms and illegal poisoning). Mean breeding success was 0.68 (SD. = 0.17) under current conditions. Annual probabilities of survival were 0.72 (SE. = 0.06) for fledglings and 2. yr old non-breeders, 0.73 (SE. = 0.04) for non-breeders older than 2. yrs old and 0.93 (SE. = 0.04) for breeders. Probabilities of recruitment were 0 for birds aged 1-4, 0.10 (SE. = 0.06) for birds aged 5 and 0.19 (SE. = 0.09) for older birds. Population viability analyses estimated an annual decline of 3-4% of the breeding population under current conditions. Our results indicate that only by combining different management actions in the breeding area, especially by removing the most important causes of human-related mortality (poisoning and collisions on wind farms), will the population grow and persist in the long term. Reinforcement with captive breeding may also have positive effects but only in combination with the reduction in causes of non-natural mortality. These results, although obtained for a focal species, may be applicable to other endangered populations of long-lived avian scavengers inhabiting southern Europe.

Large terrestrial long-lived birds (including raptors) are typically sedentary on islands, even when they are migratory on the mainland. Density-dependent variation in the age at first breeding has been described as responsible for the long-term persistence of long-lived bird populations on islands. However, sedentary island populations may also benefit from higher survival rates derived from the absence of migration costs, especially for young individuals. Thus, sedentary island populations can mimic a natural experiment to study migration costs. We estimated the age-dependent survival of two sedentary raptors on the island of Menorca (Egyptian vultures Neophron percnopterus and red kites Milvus milvus) and compared these estimates with those reported for other migratory and sedentary populations. In Menorca, Egyptian vultures, but not red kites, showed low levels of human-related mortality resulting in extremely high survival probabilities, probably due to different diet choices and behavioral patterns. Juvenile Egyptian vultures and red kites in the studied population had lower survival probabilities than adults. This difference, however, was smaller than those reported for mainland migrant populations, which showed a lower juvenile survival rate. In fact, between-population comparisons suggested that survival of the young in migrant populations may be triggered by mortality factors in wintering areas. In contrast, adult survival may respond to mortality factors in breeding areas. Our results suggest that raptor species that become sedentary on islands may benefit from higher pre-breeder survival prospects in comparison with their mainland migrant counterparts. This fact, in combination with an earlier age at first reproduction, may facilitate their persistence.

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)

In long-lived species, the age-, stage- and/or sex-dependent patterns of survival and reproduction determine the evolution of life history strategies, the shape of the reproductive value, and ultimately population dynamics. We evaluate the combined effects of age and sex in recruitment, breeder survival and breeding success of the globally endangered Egyptian vulture (Neophron percnopterus), using 31- years of exhaustive data on marked individuals in Spain. Mean age of first reproduction was 7-yrs for both sexes, but females showed an earlier median and a larger variance than males. We found an agerelated improvement in breeding success at the population level responding to the selective appearance and disappearance of phenotypes of different quality but unrelated to within-individual aging effects. Old males (≥8 yrs) showed a higher survival than both young males (≤7 yrs) and females, these later in turn not showing aging effects. Evolutionary trade-offs between age of recruitment and fitness (probably related to costs of territory acquisition and defense) as well as human-related mortality may explain these findings. Sex- and age-related differences in foraging strategies and susceptibility to toxics could be behind the relatively low survival of females and young males, adding a new concern for the conservation of this endangered species