Out of Africa: Juvenile Dispersal of Black-Shouldered Kites in the Emerging European Population.

Knowledge of animal dispersal patterns is of great importance for the conservation and maintenance of natural populations. We here analyze juvenile dispersal of the poorly studied Black-shouldered Kite ) monitored in southwestern Spain in an ongoing long-term study initiated in 2003. The European population of Black-shouldered kites is thought to be a recent one funded by colonizing African birds, as no kites have been found in the European fossil record, and the breeding population has progressively expanded to the North in the late 20th and 21st centuries.

Leucistic plumage as a result of progressive greying in a cryptic nocturnal bird.

Leucism, broadly defined as the lack of melanin pigmentation, occurs in many animal species. Most studies on leucism and other colour aberrations are based on opportunistic observations or small cross-sectional samples, thus limiting our ability to produce reliable results and test theoretical predictions. This study combines cross-sectional and longitudinal data collected in 2016-2020 from a population of red-necked nightjars (Caprimulgus ruficollis).

Taphonomic information from the modern vertebrate death assemblage of Doñana National Park, Spain.

Modern death assemblages provide insights about the early stages of fossilization and useful ecological information about the species inhabiting the ecosystem. We present the results of taphonomic monitoring of modern vertebrate carcasses and bones from Doñana National Park, a Mediterranean coastal ecosystem in Andalusia, Spain. Ten different habitats were surveyed.

Correlates of individual variation in the porphyrin-based fluorescence of red-necked nightjars (Caprimulgus ruficollis).

Many nocturnal animals, including invertebrates such as scorpions and a variety of vertebrate species, including toadlets, flying squirrels, owls, and nightjars, emit bright fluorescence under ultraviolet light. However, the ecological significance of this unique coloration so attached to nocturnality remains obscure. Here, we used an intensively studied population of migratory red-necked nightjars (Caprimulgus ruficollis) to investigate inter-individual variation in porphyrin-based pink fluorescence according to sex, age, body condition, time of the year, and the extent of white plumage patches known to be involved in sexual communication.

Cosmetic colouring by Bearded Vultures : still no evidence for an antibacterial function.

Bearded Vultures regularly visit ferruginous springs for cosmetic purposes to obtain their reddish plumage colouration. Different hypotheses have been proposed to explain this deliberate application of adventitious colouration: (1) to signal individual dominance status; (2) to exploit an anti-bacterial effect of iron oxides or ochre to reduce feather degradation by bacteria and, in parallel (3) to enable incubating birds to transfer this protection to their developing embryos to increase hatching success. Here, we re-evaluate the antibacterial hypothesis using three experimental approaches: (a) by applying feather-degrading bacteria to stained and unstained bearded vulture feathers; (b) by assessing the antibacterial activity of ochre; and (c) by comparing the breeding success of orange individuals with pale ones.

Unmanned aircraft systems as a new source of disturbance for wildlife: A systematic review.

The use of small Unmanned Aircraft Systems (UAS; also known as "drones") for professional and personal-leisure use is increasing enormously. UAS operate at low altitudes (<500 m) and in any terrain, thus they are susceptible to interact with local fauna, generating a new type of anthropogenic disturbance that has not been systematically evaluated. To address this gap, we performed a review of the existent literature about animals' responses to UAS flights and conducted a pooled analysis of the data to determine the probability and intensity of the disturbance, and to identify the factors influencing animals' reactions towards the small aircraft.

Tropical bat as mammalian model for skin carotenoid metabolism.

Animals cannot synthesize carotenoid pigments de novo, and must consume them in their diet. Most mammals, including humans, are indiscriminate accumulators of carotenoids but inefficiently distribute them to some tissues and organs, such as skin. This limits the potential capacity of these organisms to benefit from the antioxidant and immunostimulatory functions that carotenoids fulfill.

Decoration Increases the Conspicuousness of Raptor Nests.

Avian nests are frequently concealed or camouflaged, but a number of species builds noticeable nests or use conspicuous materials for nest decoration. In most cases, nest decoration has a role in mate choice or provides thermoregulatory or antiparasitic benefits. In territorial species however, decorations may serve additional or complementary functions, such as extended phenotypic signaling of nest-site occupancy and social status to potential intruders.

Unmanned Aircraft Systems complement biologging in spatial ecology studies.

The knowledge about the spatial ecology and distribution of organisms is important for both basic and applied science. Biologging is one of the most popular methods for obtaining information about spatial distribution of animals, but requires capturing the animals and is often limited by costs and data retrieval. Unmanned Aircraft Systems (UAS) have proven their efficacy for wildlife surveillance and habitat monitoring, but their potential contribution to the prediction of animal distribution patterns and abundance has not been thoroughly evaluated.

A rock engraving made by Neanderthals in Gibraltar.

The production of purposely made painted or engraved designs on cave walls--a means of recording and transmitting symbolic codes in a durable manner--is recognized as a major cognitive step in human evolution. Considered exclusive to modern humans, this behavior has been used to argue in favor of significant cognitive differences between our direct ancestors and contemporary archaic hominins, including the Neanderthals. Here we present the first known example of an abstract pattern engraved by Neanderthals, from Gorham's Cave in Gibraltar.

The earliest pigeon fanciers.

Feral Pigeons have colonised all corners of the Earth, having developed a close association with humans and their activities. The wild ancestor of the Feral Pigeon, the Rock Dove, is a species of rocky habitats, nesting typically on cliff ledges and at the entrance to large caves. This habit would have brought them into close contact with cave-dwelling humans, a relationship usually linked to the development of dwellings in the Neolithic.

Determinants and short-term physiological consequences of PHA immune response in lesser kestrel nestlings.

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) nestlings in semi-captivity conditions and with a homogeneous diet composition. We conducted a repeated measures analyses of a set of blood parameters (carotenoids, triglycerides, β-hydroxybutyrate, cholesterol, uric acid, urea, total proteins, and total antioxidant capacity), metabolic (resting metabolic rate), genotypic (MHC class II B heterozygosity), and biometric (body mass) variables.

Birds of a feather: Neanderthal exploitation of raptors and corvids.

The hypothesis that Neanderthals exploited birds for the use of their feathers or claws as personal ornaments in symbolic behaviour is revolutionary as it assigns unprecedented cognitive abilities to these hominins. This inference, however, is based on modest faunal samples and thus may not represent a regular or systematic behaviour. Here we address this issue by looking for evidence of such behaviour across a large temporal and geographical framework.

Specific appetite for carotenoids in a colorful bird.

Background: Since carotenoids have physiological functions necessary for maintaining health, individuals should be selected to actively seek and develop a specific appetite for these compounds.

Methodology/principal Findings: Great tits Parus major in a diet choice experiment, both in captivity and the field, preferred carotenoid-enriched diets to control diets. The food items did not differ in any other aspects measured besides carotenoid content.

The effect of developmental stage on eggshell thickness variation in endangered falcons.

We compared eggshell thickness of hatched eggs with that of non-developed eggs in endangered falcon taxa to explore the effect of embryo development on eggshell thinning. To our knowledge, this has never been examined before in falcons, despite the fact that eggshell thinning due to pollutants and environmental contamination is often considered the most common cause of egg failure in falcons. Because of the endangered nature of these birds, and the difficulty in gaining access to the nests and their eggs, there is a large gap in our knowledge regarding eggshell thickness variation and the factors affecting it.

Increase in membrane thickness during development compensates for eggshell thinning due to calcium uptake by the embryo in falcons.

We compared membrane thickness of fully developed eggs with those of non-developed eggs in different endangered falcon taxa. To our knowledge, membrane thickness variation during development has never been examined before in falcons or any other wild bird. Yet, the egg membrane constitutes an important protective barrier for the developing embryo.

The liver but not the skin is the site for conversion of a red carotenoid in a passerine bird.

Carotenoids may provide numerous health benefits and are also responsible for the integumentary coloration of many bird species. Despite their importance, many aspects of their metabolism are still poorly known, and even basic issues such as the anatomical sites of conversion remain controversial. Recent studies suggest that the transformation of carotenoid pigments takes place directly in the follicles during feather growth, even though the liver has been previously recognised as a storing organ for these pigments with a certain potential for conversion.

Determinants of eggshell strength in endangered raptors.

We compared eggshell strength in a group of falcon taxa including the peregrine falcon (Falco peregrinus peregrinus), the red shaheen falcon (F. peregrinus babylonicus), the saker falcon (F. cherrug), the gyr falcon (F.

Repeated sequence homogenization between the control and pseudo-control regions in the mitochondrial genomes of the subfamily Aquilinae.

In birds, the noncoding control region (CR) and its flanking genes are the only parts of the mitochondrial (mt) genome that have been modified by intragenomic rearrangements. In raptors, two noncoding regions are present: the CR has shifted to a new position with respect to the "ancestral avian gene order," whereas the pseudo-control region (PsiCR) is located at the original genomic position of the CR. As possible mechanisms for this rearrangement, duplication and transposition have been considered.

Bovine tuberculosis in Doñana Biosphere Reserve: the role of wild ungulates as disease reservoirs in the last Iberian lynx strongholds.

Doñana National Park (DNP) in southern Spain is a UNESCO Biosphere Reserve where commercial hunting and wildlife artificial feeding do not take place and traditional cattle husbandry still exists. Herein, we hypothesized that Mycobacterium bovis infection prevalence in wild ungulates will depend on host ecology and that variation in prevalence will reflect variation in the interaction between hosts and environmental risk factors. Cattle bTB reactor rates increased in DNP despite compulsory testing and culling of infected animals.

Melanin-based color variation in the Bearded Vulture suggests a thermoregulatory function.

We document a case of intraspecific variation in plumage colouration in Bearded Vultures that may have arisen as a functional response to climate conditions. Two subspecies, Gypaetus barbatus barbatus (Eurasia and North Africa populations) and Gypaetus barbatus meridionalis (Eastern and Southern Africa), have been described on the basis of plumage colour differences. The plumage of G.

Function and occurrence of facial flushing in birds.

So far overlooked as a pigment involved in visual communication, the haemoglobin contained in the blood of all birds is responsible for the red flushing colours in bare skin areas of some species. Our aim has been twofold: (1) to study sub-epidermical adaptations for blood circulation in two flushing species: the crested caracara (Polyborus plancus) and the hooded vulture (Necrosyrtes monachus), and (2) to provide the first compilation of avian species with flushing skin. The bare facial skin of both the caracara and the hooded vulture contains a highly vascularised tissue under the epidermis that may be filled with blood and would thus produce red skin colours.

Hailstorms as a cause of mass mortality of Swainson's hawks in their wintering grounds.

We describe a mass mortality event of wintering Swainson's hawks (SH, Buteo swainsoni) in central Argentina during November 2003. One hundred thirteen SH were found dead as a consequence of a single hailstorm. In addition, 14 hawks with severe injuries were recovered alive, but only 10 of these survived 1 wk later.