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Petrels are particularly sensitive to predation by introduced species. Many populations have reduced their breeding ranges, currently mainly occupying predator-free sites. Breeding range reduction leads to interspecific competition for nesting sites, which can be detrimental to petrels. Here, we evaluate how the presence of introduced mammals (cats Felis catus and rats Rattus spp.) and potential competitors for nest sites (Cory’s shearwaters Calonectris borealis and feral rock pigeons Columba livia) shape the distribution, breeding density, and breeding performance of Bulwer’s petrel Bulweria bulwerii on Tenerife, the largest and most densely human populated of the Canary Islands. We estimated nest density, assessed the role of nest location and physical characteristics of nests on breeding success, and determined causes of breeding failure by introduced predators and competitors. Nest density was higher in predator-free colonies on marine rocks. Cat presence was the best predictor of nest density, but it was not correlated with either presence or abundance of competitors. Breeding success varied between years and colonies but was not related to nest characteristics. Pigeon competition for nests was the most frequent cause of breeding failure (7.3%), followed by rat predation (6.3%). We also compared petrel and pigeon nest cavities and found considerable overlap in the physical size of nest sites. Our study provides insights into an overlooked impact of the invasive rock pigeon: nest competition with small seabirds. We encourage more research on the effects of pigeons on nest density, as well as disease and pathogen transmission, and vegetation changes within seabird colonies., Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This study was funded by the project INTERREG MAC/4.6d/157 LuMinAves

Light pollution critically affects fledglings of burrow-nesting seabirds, leading to massive mortality events. The successful management of this pollutant depends upon a comprehensive understanding of the factors influencing visual sensitivity and corresponding behaviours towards light. Factors shaping the development of the visual system could account for variation in seabirds' vulnerability to light pollution. We investigated how Cory's shearwater chicks respond to selected contrasting artificial light stimuli. Chicks were subjected to blue and red light treatments, and repeatedly tested throughout the nestling period. We analysed behavioural responses (number, timing and orientation of reactions) to determine how age, exposure to experimental light stimuli and spectra influenced the onset of visually guided behaviours, thus inferring drivers of vulnerability to light pollution. Repetitive exposure to light significantly increased the number of reactions, and chicks predominantly displayed light avoidance behaviour. We did not find differences in the number of reactions, timing and orientation between blue and red light treatments. The responses did not differ across different age groups. These results provide empirical evidence for the contribution of the light available in the rearing environment to seabird visual development. They support the hypothesis that differential exposure to light during the growth period influences responses to artificial light, and that the state of visual development at fledging could be a main driver of the age bias observed during seabird fallout events. It is thus important to evaluate lighting schemes in both urban and natural areas, and determine the as yet unknown consequences that may be affecting the populations., Fundação para a Ciência e a Tecnologia SFRH/BD/143514/2019, 190823-3, UIDB/05634/2020, UIDP/05634/2020; Marius Jakulis Jason Foundation; Government of the Azores M1.1.A/FUNC.UI&D/003/2021-2024.

The globally widespread adoption of Artificial Light at Night (ALAN) began in the mid-20th century. Yet, it is only in the last decade that a renewed research focus has emerged into its impacts on ecological and biological processes in the marine environment that are guided by natural intensities, moon phase, natural light and dark cycles and daily light spectra alterations. The field has diversified rapidly from one restricted to impacts on a handful of vertebrates, to one in which impacts have been quantified across a broad array of marine and coastal habitats and species. Here, we review the current understanding of ALAN impacts in diverse marine ecosystems. The review presents the current state of knowledge across key marine and coastal ecosystems (sandy and rocky shores, coral reefs and pelagic) and taxa (birds and sea turtles), introducing how ALAN can mask seabird and sea turtle navigation, cause changes in animals predation patterns and failure of coral spawning synchronization, as well as inhibition of zooplankton Diel Vertical Migration. Mitigation measures are recommended, however, while strategies for mitigation were easily identified, barriers to implementation are poorly understood. Finally, we point out knowledge gaps that if addressed would aid in the prediction and mitigation of ALAN impacts in the marine realm.

The main factors afecting specifc road casualty rates are related to life-history traits, road features, and landscape variables. After road inauguration, roadkill rate and spatial and temporal patterns can change substantially due to changes in trafc intensity, avoidance behaviour or local population decline. Despite the Canary Islands constituting a biodiversity hotspot, Canarian ecosystems are highly threatened because of the high human density, and studies on anthropogenic sources of mortality of wildlife are scarce. Here, we counted roadkills during two annual cycles after the inauguration of an 8.8-kmroad section on Tenerife, the largest and most densely populated island of the Canaries. We counted 694 roadkills belonging to a minimum of 19 species of birds and six species of introduced mammals. Seasonal variation was apparent during both annual cycles, particularly for birds, being the majority of victims concentrated in May and June. Although trafc intensity increased since road inauguration, the number of roadkills decreased signifcantly in the second annual cycle. The reduction in road mortality in the second cycle could be related to some non-mutually exclusive factors such as population decline, road avoidance, or weather conditions. As road networks of the Canary Islands are still increasing, further studies quantifying road mortality impacts on Canarian ecosystems and threatened species are urgently needed to guarantee the management and conservation of its fragile wildlife, Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This study was fnanced out of the own pocket of the members of Grupo de Ornitología e Historia Natural de las islas Canarias (GOHNIC)

Significant demographic fluctuations can have major genetic consequences in wild populations. The lesser kestrel (Falco naumanni) has suffered both population declines and range fragmentation during the second half of the 20th century. In this study we analysed multilocus microsatellite data to assess the genetic structure of the species. Our analysis revealed significant genetic structuring of lesser kestrel populations, not only at the cross-continental scale, but also regionally within the Central and Eastern (CE) Mediterranean region. We detected signs of genetic bottlenecks in some of the peripheral populations coupled with small effective population sizes. Values of genetic differentiation among the largest populations were low, albeit significant, whereas the small peripheral CE Mediterranean populations showed higher levels of differentiation from all other populations. Gene flow levels were relatively low among the discontinuously distributed populations of the CE Mediterranean region. We argue that the observed spatial genetic structure can be attributed at some level to the past demographic decline experienced by the species. Finally, we identify management units in the region, and inform the design of conservation actions aimed at the increase of population sizes and dispersal rates among peripheral populations., We are grateful to Action for Wildlife and ANIMA rehabilitation centres, the Lesser Kestrel Recovery project team (LIFE11 NAT/BG/360), J. Hernandez-Pliego and G. Giglio for helping with sample collection. D. Vavylis, G. Vakis and E. Toli assisted with fieldwork. LIFE for the Lesser Kestrel project team (LIFE+ 11 NAT/GR/1011), and namely K. Vlachopoulos, S. Polymeros and A. This study was financially supported by a scholarship awarded to A.B. by the A.G. Leventis Foundation.

Procellariiformes are one of the most threatened groups of birds of the world so knowledge of nesting habitat and factors affecting breeding rates are vital issues for their conservation. Although Cory's Shearwater Calonectris borealis is a well-studied seabird species on the whole, information on the relationship between its breeding parameters and nest site characteristics is quite limited. To address this gap, during 2017-2019, we conducted a study on its breeding performance on Tenerife, the largest and the most densely populated island of the Canarian archipelago. We constructed generalized linear mixed models to evaluate the potential effects of nest features on breeding performance. Two variables explained breeding success: the distance from the nest to the nearest paved road, and the presence of pebbles at the entrance of the nest-burrow, which correlated negatively and positively with breeding success, respectively. The majority of failures occurred during the incubation period. Breeding failures were mainly related to egg abandonment and rat predation upon eggs or chicks. Effective measures mitigating human-instigated disturbance (e.g. control of dogs, rats and feral cat populations, and reducing light pollution), together with studies on factors affecting demographic parameters, are needed to guarantee the long-term conservation of Cory's Shearwater and other seabird species on the main Canary Islands.—Rodriguez, B., Siverio, F., Acosta, Y. & Rodriguez, A. (2022). Breeding success of Cory's Shearwater in relation to nest characteristics and predation by alien mammals. Ardeola, 69: XX-XX.

Due to their life-history traits, the petrels are particularly sensitive to predation by introduced species. Therefore, many populations have constricted their original breeding distribution range, currently only occupying predator-free sites. In this scenario, interspecific competition for nesting sites can be detrimental for the petrel’ conservation. Here, we evaluate how the presence of introduced mammals (cats Felis catus and rats Rattus spp.) and potential competitors for nest sites (Cory’s shearwaters Calonectris borealis and feral rock pigeons Columba livia) shape the distribution, breeding density, and breeding performance of the Bulwer’s petrel Bulweria bulwerii on Tenerife, the largest and most densely populated of the Canary Islands. We estimated nest density, assessed the role of nest location and nest characteristics on breeding success, and determined causes of breeding failure by exotic predators and competitors. Nest density was higher in predator-free colonies on marine rocks. Cat presence was the best predictor for nest density, while presence or abundance of competitors had no correlation to nest density. Breeding success varied between years and colonies, but was not related to nest characteristics. Of the unequivocally determined causes of breeding failure, pigeon competition for nests was the most frequent (7.3%), followed by rat predation (6.3%). We also compared petrel and pigeon nest cavities and found a considerable overlap in nesting niche. Our study provides insight on an overlooked impact of the invasive rock pigeon: nest competition with small seabirds. We encourage more research on the effects of pigeons on nest density, disease and pathogen transmission, and vegetation changes within petrel colonies.

Forest-dwelling raptors living on islands are more vulnerable than continental relatives due to their particular life history traits and habitat degradation. The Canary Islands’ forests have suffered severe transformations because of intense human exploitation since its colonization by the Europeans. In recent decades, forest managers have initiated actions to restore the original ecosystems. Consequently, gathering knowledge on the relationships between habitat and reproduction output of forest species is essential to develop long-term conservation actions. Here, we explore the suitability of exotic tree plantations as breeding habitat for an island endemic raptor, the Macaronesian sparrowhawk Accipiter nisus granti. We monitored territories distributed in three main forest types, two native (laurel forest and Canarian pinewood) and one composed of exotic trees. We assessed breeding density, characterized nesting habitat at macro-, micro-habitat and nest tree levels, and estimated breeding parameters in the three forests. We evaluated habitat selection and its potential relationship with breeding parameters, as well as nest structure survival in native versus exotic tree species. Density was higher in exotic forests and habitat features differed among forests at three spatial scales. Sparrowhawks used areas with high cover of exotic trees, with high trees, far away from human settlements and at low altitudes. All models testing for differences in breeding success and productivity among the forest types were not significant, but the percentage of successful pairs was slightly higher in exotic tree plantations than in native forests. Nest structures located in exotic trees showed a higher annual survival than those placed in native trees. Our results indicate that exotic plantations are a secure nesting habitat and therefore forestry practices, including those aiming to eradicate exotic trees, must be carefully planned to avoid nest destruction or disturbance in occupied forest patches

The Lesser kestrel (Falco naumanni) evolved as a separate species in the Old-World kestrel radiation starting in the late Miocene. Given that the first cities were erected in the Holocene, this urban colonial raptor has only become a major town dweller recently in its evolutionary history. Today, more than 95% of lesser kestrel colonies in Spain and other Mediterranean countries are on buildings, and the remaining few are on rocky outcrops, that may have been the original nesting substrate for this cavity-nesting bird. Lesser kestrel fossils are well represented in cave sites, and their paleontological distribution, spanning from the Early Paleolithic to the Epipaleolithic, agrees well with its current breeding distribution. According to classical sources, such as the works of Columella and Pliny the Elder, and the presence of a skeletal remain in a Roman villa near Madrid, lesser kestrels may have nested in buildings and in urban settings for at least 2000e2500 years. However, there are no surviving colonies in structures older than 1400 years in Andalusia, nor in Spain. For a sample of 349 colonies on ancient buildings, a majority of the structures had been erected between the 15th and 17th centuries, this putting a time limit of about 300- 600 years to the existence of those seemingly immemorial colonies. For specific towns and buildings, written references for the presence of lesser kestrel colonies do not go back more than two centuries. In fact, the Cathedral of Sevilla may be the structure with the longest continuous occupation by lesser kestrels recorded up to present time, from 1834 to 2020. Lesser kestrels were possibly too common in human settlements in the past as to be noted as special. This may explain the scarcity of references to the species until the 19th century. In any case, the same lack of information affects the other major Eurasian urban birds, as no timeline exist for the urbanization process of any other bird species. We propose that lesser kestrels became urban breeders when both adequate cavities in buildings and cereal fields, where they capture their invertebrate prey, became available in their breeding range, several millennia ago. However, urban colonies, in contrast with the ones on stable geological substrates, have been forced to move from building to building when older ones became ruinous or were rebuilt, but new structures with suitable cavities became available throughout History.

Context Urbanization and artificial light at night (ALAN) are major drivers of local biodiversity losses causing community alterations, disruption of predator-prey interactions, and ultimately, promotion of cascading effects. However, some species can colonize urban environments. Objectives We explore the role of ALAN as a driver of the colonization of urban environments by a nocturnal avian predator, the burrowing owl Athene cunicularia. Methods We studied in a suburban locality in La Pampa, Argentina: (1) prey availability with pitfall traps under streetlights and control sites; (2) diet by analyzing pellets; (3) space use by deploying GPS data-loggers to breeding owls; (4) nesting habitat selection by comparing environmental variables at nest and random locations; and (5) productivity by correlating environmental variables with the number of fledglings. Results First, streetlights altered the invertebrate availability, attracting them to illuminated areas. Second, the owl diet was more similar to the invertebrate taxa trapped at pitfall traps under streetlights than that in control traps. Third, owl space use was determined by streetlights. Owls spent more time around light sources, particularly during the nighttime. Fourth, the most important habitat feature influencing the nesting habitat selection was the distance to streetlight. Owls selected areas close to streetlights for nesting. Finally, productivity was not explained by any of our habitat variables. Conclusions We demonstrate that ALAN alters the availability of invertebrates and plays a role in the diet, space use, and occupation of urban burrowing owls. Streetlights increase foraging efficiency for owls due to the clumping of prey attracted to lights. This predator-prey relationship might be only supported in suburban environments where low urbanization levels let burrowing owls nest in bare ground areas, and invertebrates are attracted to ALAN from surrounding wilder areas.

Wildlife watching is an emerging ecotourism activity around the world. In Australia and NewZealand,nightviewingoflittlepenguinsattractshundredsofthousandsofvisitorsperyear.Aspenguinsstartcomingashoreaftersunset,artificiallightingisessentialtoallowvisitorstoviewtheminthedark.Thisalterationofthenightscapewarrantsinvestigationforanypotentialeffectsof artificial lighting on penguin behavior. We experimentally tested how penguins respond todifferentlightwavelengths(colors)andintensitiestoexamineeffectsonthecolonyattendancebehaviorattwositesonPhillipIsland,Australia.Atonesite,nocturnalartificialilluminationhasbeenusedforpenguinviewingfordecades,whereasattheothersite,theonlylightisfromthenaturalnightsky.Lightintensitydidnotaffectcolonyattendancebehaviorsofpenguinsatthearti-ficiallylitsite,probablyduetopenguinhabituationtolights.Atthenotpreviouslylitsite,penguinspreferredlitpathsoverdarkpathstoreachtheirnests.Thus,artificiallightmightenhancepen-guinvisionatnightandconsequentlyitmightreducepredationriskandenergeticcostsofloco-motionthroughobstacleandpathdetection.Althoughpenguinsarefaithfultotheirpath,theycanbedrawntoartificiallightsatsmallspatialscale,solightpollutioncouldattractpenguinstounde-sirablelitareas.Whenartificiallightingisrequired,werecommendkeepinglightingasdimandtime-restrictedaspossibletomitigateanynegativeeffectsonthebehaviorofpenguinsandtheirnaturalhabitat

Artificial lights at night cause high mortality of seabirds, one of the most endangered groups of birds globally. Fledglings of burrow-nesting seabirds, and to a lesser extent adults, are attracted to and then grounded (i.e., forced to land) by lights when they fly at night. We reviewed the current state of knowledge of seabird attraction to light to identify information gaps and propose measures to address the problem. Although species in families such as Alcidae and Anatidae can be grounded by artificial light, the most affected seabirds are petrels and shearwaters (Procellariiformes). At least 56 species of Procellariiformes, more than one-third of them (24) threatened, are subject to grounding by lights. Seabirds grounded by lights have been found worldwide, mainly on oceanic islands but also at some continental locations. Petrel breeding grounds confined to formerly uninhabited islands are particularly at risk from light pollution due to tourism and urban sprawl. Where it is impractical to ban external lights, rescue programs of grounded birds offer the most immediate and employed mitigation to reduce the rate of light-induced mortality and save thousands of birds every year. These programs also provide useful information for seabird management. However, these data are typically fragmentary, biased, and uncertain and can lead to inaccurate impact estimates and poor understanding of the phenomenon of seabird attraction to lights. We believe the most urgently needed actions to mitigate and understand light-induced mortality of seabirds are estimation of mortality and effects on populations; determination of threshold light levels and safe distances from light sources; documentation of the fate of rescued birds; improvement of rescue campaigns, particularly in terms of increasing recovery rates and level of care; and research on seabird-friendly lights to reduce attraction.

One of the most critical phases in the life of petrels (Procellariiformes) is at fledging when young birds pass from parental dependence on land to an independent life at sea. To mitigate mortality at this time, rescue programs are implemented near breeding sites around the world, especially for birds grounded by artificial lights. We evaluated the plumage and body condition of short-tailed shearwater (Ardenna tenuirostris) fledglings captured at colonies just before departure in comparison to fledglings washed up on beaches and to fledglings attracted by artificial light along roads. We measured abundance of down, body mass, and body condition index as the standardized residuals of a regression of body mass on size, and employed linear models to test differences on body mass and body condition between locations. Beach-washed birds were underweight and in poor condition, suggesting their future survival probabilities at sea were low. Birds rescued on roads as a consequence of light attraction had lower body weights and condition indices than fledglings captured at the colony. However, more than 50% of light-attracted birds had attained similar weights to those of adults, suggesting they have higher probabilities of survival than beach-washed birds. Water-logged birds being washed onto beaches is a natural process, but birds grounded by lighting along roads is an increasing anthropogenic threat that requires management. Thus, management and conservation efforts should be directed to protect birds in the colonies and reduce light-induced mortality, ideally through the strategic reduction of light sources and lateral light spillage. When resources for conservation are limited, rescue programs should focus on rescuing birds from roads rather than beach-washed birds, which have a lower probability of survival. © 2017 The Wildlife Society.

The specific spatial distribution and habitat association—strongly influenced by environmental factors or competitive interactions—are major issues in ecology and conservation. We located and georeferenced nesting sites of five cliff-nesting raptors (Egyptian vulture Neophron percnopterus [a locally extinct species], common buzzard Buteo buteo, osprey Pandion haliaetus, common kestrel Falco tinnunculus, Barbary falcon Falco peregrinus pelegrinoides), and common raven Corvus corax on one of the most biodiverse hotspot within the Canary Islands (Teno, Tenerife). We used generalized linear models to evaluate the factors affecting abundance, richness, and intra- and interspecific interactions. Raptor abundance increased with slope, shrub-covered area, and habitat diversity, and decreased with altitude, and forested and grassed areas. Richness increased with slope and decreased with altitude. Threatened species (osprey, Barbary falcon, and raven) occupied cliffs farther away from houses and roads, and more rugged areas than the non-threatened species. The models suggested that the probability of cliff occupation by buzzards, falcons, and ravens depended only on inter-specific interactions. Buzzard occupation increased with the distance to the nearest raven and kestrel nests, whereas falcons and ravens seek proximity to each other. Teno holds between 75% and 100% of the insular breeding populations of the most endangered species (osprey and raven), indicating the high conservation value of this area. Our study suggests that the preservation of rugged terrains and areas of low human pressure are key factors for raptor conservation and provide basic knowledge on the community structure and habitat associations to develop appropriated management actions for these fragile island populations

The taxonomy of Procellariiformes, particularly petrels and shearwaters, is still unresolved. The Manx shearwater Puffinus puffinus is one of the best studied seabirds worldwide. Most of the information known on this seabird is focused on the northern core populations where the species is abundant. However, the species shows a high number of peripheral populations, which are extremely small and difficult to study in comparison to central populations. Using an integrative approach, we provided significant evidence of phenological, morphological, acoustic, plumage colour, and genetic differentiation of the Canarian Manx shearwaters (the most southern population) from the northern breeding colonies, which is compatible with a long period of isolation. Birds from the Canary Islands breed around 2‐3 months earlier, are smaller and lighter, and show darker underwing plumage than those from northern populations. In addition, Canarian call features are different from the northern populations. Finally, genetic analyses of the mitochondrial control region indicate an incipient genetic differentiation of Canarian Manx shearwaters from the other breeding populations. The Canarian population holds a small number of breeding colonies and it is declining, so accurate taxonomic recognition critically affects conservation efforts. For all the aforementioned reasons, we propose to rank the Canarian breeding population as a new taxon by presenting the formal description of a new subspecies Puffinus puffinus canariensis ssp. nova.

Grouping is a widespread form of predator defence, with individuals in groups often performing evasive collective movements in response to attack by predators. Individuals in these groups use behavioural rules to coordinate their movements, with visual cues about neighbours’ positions and orientations often informing movement decisions. Although the exact visual cues individuals use to coordinate their movements with neighbours have not yet been decoded, some studies have suggested that stripes, lines, or other body patterns may act as conspicuous conveyors of movement information that could promote coordinated group movement, or promote dazzle camouflage, thereby confusing predators. We used phylogenetic logistic regressions to test whether the contrasting achromatic stripes present in four different taxa vulnerable to predation, including species within two orders of birds (Anseriformes and Charadriiformes), a suborder of Artiodactyla (the ruminants), and several orders of marine fishes (predominantly Perciformes) were associated with group living. Contrasting patterns were significantly more prevalent in social species, and tended to be absent in solitary species or species less vulnerable to predation. We suggest that stripes taking the form of light-coloured lines on dark backgrounds, or vice vers a , provide a widespread mechanism across taxa that either serves to inform conspecifics of neighbours' movements, or to confuse predators, when moving in groups. Because detection and processing of patterns and of motion in the visual channel is essentially colour-blind, diverse animal taxa with widely different vision systems (including mono-, di-, tri-, and tetrachromats) appear to have converged on a similar use of achromatic patterns, as would be expected given signal-detection theory. This hypothesis would explain the convergent evolution of conspicuous achromatic patterns as an antipredator mechanism in numerous vertebrate species.

Despite the increase of literature on seabird plastic ingestion in recent years, few studies have assessed how plastic loads vary according to different sampling methods. Most studies use necropsies of seabirds with a natural cause of death, e.g. beached or predated, to determine plastic loads and monitor marine debris. Sampling naturally dead seabirds may be biased as they have perished because of their intrinsic factors, e.g. poor body condition, high parasite loads, sickness or predation, affecting estimates of plastic loads. However, seabirds killed accidentally may be more representative of the population. Here, we used the short-tailed shearwater Ardenna tenuirostris to test different sampling methods: naturally beached fledglings and accidentally road-killed fledglings after being attracted and grounded by artificial lights. We compared plastic load, body condition, and feeding strategies (through using feathers’ δ13C and δ15N isotope niche) between beached and road-killed fledglings. Beached birds showed higher plastic loads, poorer body condition and reduced isotopic variability, suggesting that this group is not a representative subsample of the whole cohort of the fledgling population. Our results might have implications for long-term monitoring programs of seabird plastic ingestion. Monitoring plastic debris through beached birds could overestimate plastic ingestion by the entire population. We encourage the establishment of refined monitoring programs using fledglings grounded by light pollution if available. These samples focus on known cohorts from the same population. The fledgling plastic loads are transferred from parents during parental feeding, accumulating during the chick-rearing period. Thus, these fledglings provide a higher and valuable temporal resolution, which is more useful and informative than unknown life history of beached birds.

Capsule Flowers of an invasive plant species are more visited by native birds than flowers of ornithophilous endemic plants. Aims To describe the bird guild and its behaviour visiting the century plant Agave americana in an insular environment and to determine which factors are affecting visitation rates. Methods We noted number and species of birds visiting inflorescences on Tenerife, Canary Islands. We used multimodel inference of generalized linear models to analyse the factors affecting the number of visits and the visitor species richness. Results Eighty-one per cent of inflorescences were visited by eight native bird species. All species fed on nectar and only the Atlantic Canary fed also on pollen. Foraging behaviour varied among species. Visitation rate increased with density and diversity of birds and flower characteristics and decreased through the day. The number of species visiting the inflorescences increased with diversity and density of birds in the surroundings and decreased through the day. Conclusion The native bird community uses the invasive century plant as a feeding resource at a higher rate than it uses endemic ornithophilous plants. This could have negative effects for the pollination of endemic plants, but positive effects for birds

Plants, unlike animals, are organisms with a sessile adult stage, and consequently they need external vectors for moving their propagules (mainly seeds) away from mother plants. The movement of seeds is a central process in the life cycle of plants called seed dispersal (Howe and Smallwood 1982). This process determines the spatial pattern of seed deposition, over which post-dispersal processes such as predation, germination, or seedling survival will act (Nathan and Muller-Landau 2000). Seed dispersal will therefore influence significantly the probability that a single seed becomes an adult individual of the plant population. The advantages of moving away from source plants are multiple. From a demographic point of view, seed dispersal enables to escape seeds to high mortality in the vicinity of maternal plants, where the probability of predation or pathogen infection increases exponentially (Janzen 1970; Connell 1971). In addition, dispersal facilitates the arrival of seeds to suitable microhabitats for germination and survival of seedlings, the colonization of new habitats, and the range expansion of plant populations (Howe and Smallwood 1982). From a genetic point of view, together with pollination, seed dispersal shapes patterns of gene flow within and among plant populations, influencing the characteristics and the cohesiveness of genetic pools at local and regional scales (Loveless and Hamrick 1984). Thus, as whole, seed dispersal will influence the demogenetic features of plant populations, conditioning the regeneration dynamics and the adaptability and resilience of plant populations in changing landscapes.

The loss of largest-bodied individuals within species of frugivorous animals is one of the major consequences of defaunation. The gradual disappearance of large-bodied frugivores is expected to entail a parallel deterioration in seed dispersal functionality if the remaining smaller-sized individuals are not so effective as seed dispersers. While the multiple impacts of the extinction of large bodied species have been relatively well studied, the impact of intraspecific downsizing (i.e. the extinction of large individuals within species) on seed dispersal has rarely been evaluated. Here we experimentally assessed the impact of body-size reduction in the frugivorous lizard Gallotia galloti (Lacertidae), an endemic species of the Canary Islands, on the seed germination patterns of two fleshy-fruited plant species (Rubia fruticosa and Withania aristata). Seed germination curves and the proportions of germinated seeds were compared for both plant species after being defecated by large-sized individuals and small-sized individuals. The data show that seeds of W. aristata defecated by larger-sized lizards germinated faster and in a higher percentage than those defecated by small-sized lizards, while no differences were found for R. fruticosa seeds. Our results suggest that disappearance of the largest individuals of frugivorous species may impair recruitment of some plant species by worsening seed germination. They also warn us of a potential cryptic loss of seed dispersal functionality on defaunated ecosystems, even when frugivorous species remain abundant

We studied the post-fledging movement of two sibling (male and female) juvenile Barbary Falcons (Falco peregrinus pelegrinoides) hatched in Lanzarote (Canary Islands) in 2011 using satellite tracking. Birds were tracked from fledging in May to the end of November, when the signals of both transmitters were lost. During the first 45 d following fledging, both birds behaved similarly and made some flights 3000 km from the nest, probably using a ship as a perch. Because Barbary Falcon populations of the Canary Islands are listed as >threatened> due to anthropogenic threats (e.g. collisions with human-made structures, illegal shooting, nest-robbing; and hybridization with escaped falconry falcons) and little is known about their post-fledging dispersal movements, more studies of such life-history characteristics, using ringing and remote sensing, are urgently needed to develop management actions for their conservation.

Atropellos mortales de aves en Aragón, España La expansión de la red viaria y el aumento del tráfico de vehículos se han convertido en una amenaza importante para los vertebrados en el último siglo. Algunas estimaciones sitúan entre 2 y 9 millones de individuos afectados anualmente en Europa, con variaciones entre países. En España existen pocos estudios a escala nacional y autonómica. En este estudio se ha utilizado la base de datos del Centro de Recuperación de Fauna Silvestre de La Alfranca para determinar la localización, temporalidad e incidencia de los atropellos de avifauna que se producen en la comunidad autónoma de Aragón. Se han detectado 643 atropellos mortales de aves silvestres (71 especies) entre los años 2012 y 2014. Nueve de estas especies presentan una incidencia de atropellos alta; cuatro, una incidencia moderada, y 57, una incidencia baja. La especie con la mayor incidencia fue el buitre leonado (120 individuos). La distribución espacial de los atropellos fue heterogénea y julio, agosto y septiembre fueron los meses con mayor incidencia. Se identificaron 41 áreas de incidencia alta de atropellos, usando el índice de atropellos mortales por kilómetro (RI): 28 en la provincia de Zaragoza, 9 en la de Huesca y 4 en la de Teruel. Se proponen una serie de estrategias de gestión con el fin de reducir esta amenaza para las aves silvestres., The increase in road networks and vehicular traffic has posed a major threat to vertebrates over the last century. Although it is difficult to determine the annual number of avian–vehicle collisions, 2 to 9 million roadkills have been estimated for Europe, with numbers varying from country to country. Few studies have been conducted at a national or regional level in Spain. In this study we used data from La Alfranca Wildlife Rehabilitation Centre database to determine location, season and incidence of avian–vehicle collisions in the autonomous county of Aragon (Spain). A total of 643 wild birds representing 71 species were killed on roads between 2012 and 2014. Nine of these species have a high incidence of avian–vehicle collisions, four a moderate incidence, and 57 a low incidence. The species with the highest incidence was the griffon vulture (120 individuals). Spatial distribution of avian–vehicle collisions was heterogeneous, and the incidence was highest in July, August and September. We identified 41 reas of high roadkill occurrence, using a number of roadkills per km index (RI): 28 in the province of Zaragoza, 9 in Huesca and 4 in Teruel. Management strategies are proposed to reduce this threat on wild birds.

For many decades, the spectral composition of lighting was determined by the type of lamp, which also influenced potential effects of outdoor lights on species and ecosystems. Light-emitting diode (LED) lamps have dramatically increased the range of spectral profiles of light that is economically viable for outdoor lighting. Because of the array of choices, it is necessary to develop methods to predict the effects of different spectral profiles without conducting field studies, especially because older lighting systems are being replaced rapidly. We describe an approach to predict responses of exemplar organisms and groups to lamps of different spectral output by calculating an index based on action spectra from behavioral or visual characteristics of organisms and lamp spectral irradiance. We calculate relative response indices for a range of lamp types and light sources and develop an index that identifies lamps that minimize predicted effects as measured by ecological, physiological, and astronomical indices. Using these assessment metrics, filtered yellow-green and amber LEDs are predicted to have lower effects on wildlife than high pressure sodium lamps, while blue-rich lighting (e.g., K ≥ 2200) would have greater effects. The approach can be updated with new information about behavioral or visual responses of organisms and used to test new lighting products based on spectrum. Together with control of intensity, direction, and duration, the approach can be used to predict and then minimize the adverse effects of lighting and can be tailored to individual species or taxonomic groups.

The use of artificial light at night and its ecological consequences are increasing around the world. Light pollution can lead to massive mortality episodes for nocturnally active petrels, one of the most threatened avian groups. Some fledglings can be attracted or disoriented by artificial light on their first flights. Studies testing the effect of artificial light characteristics on attractiveness to seabirds have not provided conclusive results and there is some urgency as some endangered petrel species experience high light-induced mortality. We designed a field experiment to test the effect of three common outdoor lighting systems with different light spectra (high pressure sodium, metal halide and light emitting diode) on the number and the body condition of grounded fledglings of the short-tailed shearwater Ardenna tenuirostris. A total of 235 birds was grounded during 99 experimental hours (33 h for each treatment). 47% of birds was grounded when metal halide lights were on, while light emitting diode and high pressure sodium lights showed lower percentages of attraction (29% and 24%). Metal halide multiplied the mortality risk by a factor of 1.6 and 1.9 respectively in comparison with light emitting diode and high pressure sodium lights. No differences in body condition were detected among the birds grounded by the different lighting systems. We recommend the adoption of high pressure sodium lights (or with similar spectra) into petrel-friendly lighting designs together with other light mitigation measures such as light attenuation, lateral shielding to reduce spill and appropriate orientation.

Individual immune responses are likely affected by genetic, physiological, and environmental determinants. We studied the determinants and short-term consequences of Phytohaemagglutinin (PHA) induced immune response, a commonly used immune challenge eliciting both innate and acquired immunity, on lesser kestrel (Falco naumanni)nestlingsinsemi-captivity conditions and with a homogeneous diet composition. We conducted a repeated measures analyses of a set of blood parameters(carotenoids,triglycerides,b-hydroxybutyrate,cholesterol,uricacid,urea,totalproteins,and totalantioxidantcapacity),metabolic(restingmetabolicrate),genotypic(MHCclassIIBheterozygosity), and biometric (body mass) variables. PHA challenge did not affect the studied physiological parameters on a short-term basis (

Peregrine Falcons (Falco peregrinus) on the Canary Islands are considered to be of the Barbary Falcon subspecies (F. p. pelegrinoides). Here we report on lost falconry birds present among the wild population of resident falcons, and provide rough approximations of their abundance for Tenerife, the largest island of the Canaries. We observed lost falconry birds breeding with natural wild falcons, with at least one mixed pair producing fledglings. Only 54.1% of the breeding adults that we studied on the island showed typical Barbary Falcon plumage. Some nest sites were systematically poached, affecting the overall productivity of the population. Our findings suggest that the original Canarian Barbary Falcon population could be suffering from genetic mixing due to the presence of individuals originating from outside the population and from illegal harvest of nestlings. We recommend that local authorities continue to assess the degree of genetic admixture that occurs in this population, modify the current falconry regulations, implement management actions to prevent new escapes, eradicate exotic raptors, and put a stop to illegal nestling harvests.

The evolution of bird plumage colouration may be explained by a wide range of selective pressures, includ- ing both defensive and advertising needs. However, the relationship between plumage colouration and body size has never been investigated in detail. Here we hypothesize that body size represents a constraint for the evolution of plumage colour heterogeneity because the relative number of body feathers was suggested to increase as body size decreases, and in the case of carotenoid-based colourations because the concentrations of circulating carotenoids decrease with increasing body size. Here we test these predictions on a dataset comprising measurements of male plumage colour heterogeneity using a model of avian visual perception in 111 species from 55 families of birds. A test of the correlation between number of feathers and body size in 92 species of birds showed a positive, instead of nega- tive as previously suggested, association between these variables. As predicted, there was a negative relationship between plumage colour heterogeneity (measured as colour span, a measure of the contrast among colour patches) and body size after controlling for the effects of phylogeny, sexual dichromatism, colour vision type and habitat, and we suggest that the negative allometry shown by carotenoid levels may be the mechanism responsible for this negative relationship. Plumage colour heterogeneity was lower in species inhabiting open environments than in more vegetat- ed habitats. Our results offer a general explanation for interspecific variation in bird colour heterogeneity through an association with body size.

Thebreeding foraging andpost-breedingdispersal movementsof five satellite-tagged Bulwer’s Petrels fromthe Canary Islands were recorded. Foraging trips lasted 5.6 days in average (n=3), while the meandistance covered was1261km,andforaging areas were located over the continental slope andthe adjacent pelagic waters, around 1200–2000 mdepth and up to 350 kmfromthe colony. After the chick-rearing period, birds dispersed southwestwards to the tropical waters of the central Atlantic

Every year and across the world, thousands of fledglings of different petrel species crash into human structures because they are disorientated by artificial lights during their first flights. As this phenomenon is rather predictable, rescue campaigns are organized to help birds to reach the ocean, but unfortunately, a low proportion gets hurt or dies. Despite the huge number of affected individuals, and the fact that the problem was detected a long time ago, little is known on this source of mortality. We have studied the factors (i.e. body condition, plumage development, fledging date and sex) influencing the mortality of Cory's Shearwater Calonectris diomedea fledglings stranded inland due to light pollution in Tenerife (Canary Islands) during two consecutive breeding seasons (2009 and 2010). Late fledglings showed lower values of a body condition index than early ones. No sex biases were detected, neither considering stranded birds overall, nor for recovery dates or in the body condition of rescued fledglings. Our results indicate that late birds stranded by lights showing abundant down are more susceptible to fatal collisions and that the lights do not selectively kill birds with lower body condition indices. An enhancement of veterinary care should be done during the last part of the fledging period when more fatal collisions occur, especially focused on fledglings with abundant down. More research to determine why some individuals end up disoriented around artificial lights and others do not is urgently needed to minimize or prevent fallouts.

Territory spacing and breeding rates of an insular population (north-western Tenerife, Canary Islands) of Barbary Falcon Falco peregrinus pelegrinoides was studied from 1993 to 2008. The population increased constantly since the outset, from two pairs in 1993 to 12 in 2008. Mean density was 5.48 pairs per 100 km² and mean nearest neighbour distance was 3 119 m. The regularity of the spatial distribution pattern of the nests, observed in most years, may be maintained in the future despite the expectation that new pairs may occupy still-vacant territories. Considering the 79 breeding attempts analysed, the mean number of fledged young per territorial pair was 1.92, per laying pair was 2.0 (n = 76), and per successful pair was 2.24 (n = 68). No significant variations were observed between the annual mean number of fledged young per laying pair, nor between the number of fledged young of pairs according to density in a 5 km radius. All fledglings (brood size one to four) left the nest in the month of May. In order to avoid affecting breeding success, sporting activities practised in the breeding areas must be correctly managed by the appropriate authorities

The secretive breeding behaviour of petrels makes monitoring their breeding populations challenging. To assess population trends of Cory’s Shearwater Calonectris diomedea, Bulwer’s Petrel Bulweria bulwerii and Macaronesian Shearwater Puffinus baroli in Tenerife from 1990 to 2010, we used data from rescue campaigns that aim to reduce the mortality of fledgling petrels attracted to artificial lights as proxies for trends in breeding population size. Despite increases in human population size and light pollution, the number of rescued fledglings of Cory’s Shearwater and Bulwer’s Petrel increased and remained stable, respectively, whereas numbers of rescued Macaronesian Shearwaters sharply declined. In the absence of more accurate population estimates, these results suggest a worrying decline in the Macaronesian Shearwater’s breeding population.

Gathering knowledge about the migratory routes and wintering areas of threatened populations is fundamental for their successful conservation. Here, we used a non-invasive approach that relies on major histocompatibility complex (MHC) polymorphism to infer the breeding origin of a long-distance migratory bird, the lesser kestrel Falco naumanni, in its most important wintering quarters in the Sub-Saharan Africa (Senegal and South Africa). Private alleles support a strong connectivity between wintering Senegalese and western European breeding populations. On the other hand, birds wintering in South Africa were genetically differentiated with respect to western European breeding populations and might therefore gather individuals from the eastern distribution range. This study demonstrates that, at least at wide continental scales, MHC genes can be powerful intrinsic markers to study migration and migration connectivity, thus adding value to its role in conservation and management.

We studied the causes of raptor admissions to the only wildlife rehabilitation center on the largest island of the Canarian Archipelago (Tenerife) over ten years (1998–2007). A total of 2611 birds of prey, belonging to nine falconiform diurnal raptor and four strigiform species, were admitted. The Eurasian Kestrel (Falco tinnunculus) and the Long-eared Owl (Asio otus) were the species most commonly admitted and jointly made up 85.6% of admissions. The most frequent causes of admission to the wildlife rehabilitation center were collisions (with cars, high-voltage electric transmission towers, etc.; 42.2%), starvation (5.1%) and entanglement in glue traps intended for rodents (4.7%). Poisoning and shooting were recorded for 2.4 and 1.5% of the birds admitted, respectively. Only collisions increased during the study period. A total of 1010 birds (44.4% of the total) were released to the wild following rehabilitation. We recommend more financial support for rehabilitation centers to develop detailed ...