La Tour du Valat

Spatial sampling error remains a critical yet underappreciated challenge in abundance estimation, particularly when sampling processes are not explicitly accounted for. A persistent belief holds that increasing sample size compensates for sampling bias, while overlooking how spatial sampling processes — such as preferential or convenience sampling — shape these errors. Relying on the decomposition of sampling error into components driven by sample selectivity, incompleteness, and statistical population heterogeneity, we derive analytical results linking characteristics of the realized sample to properties of the underlying sampling process. Using simulated examples, we illustrate how five sampling processes — four archetypal (equal-propensity, preferential, spatial-spread, and road-based sampling) and one composite opportunistic process combining several of these mechanisms — influence the reliability of abundance estimates. Our results show how increasing sample size alone — a common reflex in monitoring — improves precision but fails to correct for bias caused by selective sampling. This is particularly relevant for citizen science, where massive datasets may yield precise yet systematically misleading inferences if spatial sampling processes are ignored. We advocate for a shift from a reliance on sample size toward the explicit characterization of sampling processes and the prioritization of probability-based sampling designs where feasible. By treating sampling error as a process-driven phenomenon, this work provides a contribution toward more rigorous and transparent ecological inference. The resulting framework is presented from a methodological perspective, specifically targeting quantitative ecologists, biometricians, and wildlife statisticians involved in designing studies, implementing monitoring programs, or analyzing citizen science data.

Wetlands are among the most threatened ecosystems worldwide, and their loss increasingly compromises landscape connectivity essential for persistence of waterbird populations. In the Mediterranean region, and particularly in northwestern Africa, conservation prioritisation has largely focused on sites supporting high bird numbers, while the role of wetlands in maintaining functional connectivity remains poorly understood. Here, we quantify wetland connectivity in Morocco using the black-headed gull (Chroicocephalus ridibundus) as a model migratory waterbird. We obtained high-resolution GPS tracking for 64 individuals breeding in south-western Iberia. We combined the tracks of the 19 individuals that moved to Morocco with network analyses, to identify key sites and habitat types that contribute to spatial connectivity. Tracked gulls relied on a heterogeneous network of 26 wetlands, including rivers, dams, lagoons and temporary wetlands. They also used anthropogenic habitats such as landfills and wastewater treatment plants. Network analyses revealed a sparsely connected but spatially structured system, with connectivity concentrated in three main geographical regions. Several unprotected wetlands, particularly rivers and reservoirs, showed high betweenness values revealing their importance for maintaining network integrity, comparable to those of existing Ramsar sites. Removal simulations highlighted the vulnerability of connectivity to the loss of a small number of key sites (nodes) in the wetland network. Furthermore, GPS data show that Moroccan wetlands are more important for black-headed gulls from July to September than expected from eBird data. Our results demonstrate how incorporating movement-based connectivity metrics can improve wetland conservation planning. Protecting functionally important wetlands is critical to safeguard waterbird connectivity, and hence ecosystem resilience, in northwestern Africa.

Triggered by global warming there is increasing interest in understanding why conspecific populations differentiate along latitudinal gradients. Although microbiomes may shape host traits and vary geographically, how hosts differentially assemble microbiomes across latitudes and how this shapes latitudinal patterns in host trait values has been understudied. This is especially true for organisms with complex life cycles, where metamorphosis may reset the microbiome. We examined microbiome composition along a latitudinal gradient and assessed the relative influence of host and environment in shaping the microbiome of the damselfly Ischnura elegans. We sampled bacterioplankton from high-latitude (southern Sweden) and low-latitude (southern France) ponds, along with larval gut and adult abdominal microbiomes from I. elegans inhabiting these ponds. Additionally, we conducted a reciprocal translocation experiment in which larvae with a strongly depleted gut microbiome were transferred between three high- and three low-latitude ponds, allowing microbiome reassembly from the local bacterioplankton, and quantified the growth rate of the larvae. We found latitudinal differences in bacterioplankton and host-associated microbiomes in adults and to a lesser extent in larvae, highlighting differences in microbiome composition across the latitudinal gradient and suggesting strong environmental effects on microbiome reassembly. Moreover, despite these differences, larvae and adults shared a small proportion of their microbiome (ca 15.83%). The reciprocal translocation experiment revealed that microbiome reassembly in microbiome-depleted larvae was primarily shaped by the local environment, rather than the host source population or latitude, underscoring the strong influence of environmental filtering in shaping microbiome composition. Moreover, phenotypic differences in larval growth rate between high- and low-latitude populations disappeared after the seven-day translocation, suggesting that local environmental conditions overruled any underlying genetic differentiation. By combining microbiome sampling across latitudes with a novel reciprocal translocation approach using microbiome-depleted larvae, our study provides key insights into how the environment shapes host–microbiome associations along geographic gradients.

Jean Jalbert est depuis plus de vingt ans aux commandes de la Tour du Valat, Institut de recherche pour la conservation des zones humides méditerranéennes, fondé en 1954 par Luc Hoffmann et qui se situe sur un domaine de près de 3 000 ha au coeur de la Camargue. Fort de 72 années d'expériences, l'Institut irradie aujourd'hui bien au-delà des pays méditerranéens et noue des partenariats avec de nombreuses régions dans le monde. Jean Jalbert a reçu L'OISEAU MAG et a bien voulu revenir sur son parcours personnel et les projets de l'Institut, les difficultés rencontrées et les espoirs.

Statut internuptial de la Pie-grièche méridionale Lanius meridionalis dans le Grand-Ouest. Les données relatives à la présence hivernale de la Pie-grièche méridionale dans le Grand Ouest de la France restent rares et majoritairement issues d’observations opportunistes. Nous analysons ici les données collectées dans les différentes bases naturalistes entre 2011 et 2025 afin de décrire la répartition géographique des individus, les facteurs influençant sa distribution, la phénologie internuptiale de l’espèce, la durée de présence des individus et l’évolution temporelle du nombre d’observations. Les résultats montrent une présence majoritairement concentrée entre septembre et mars, avec des durées de séjour variables selon le mois. Aucune tendance temporelle significative du nombre d’observations n’est mise en évidence. L’ensemble des analyses converge vers l’hypothèse d’une occupation internuptiale périphérique, rare mais récurrente, possiblement en déclin sur le court terme, dont les mécanismes et l’évolution potentielle méritent un suivi attentif.

Résultats des comptages concertés des oiseaux d’eau des Traicts du Croisic et des marais salants de Guérande (Loire-Atlantique) pendant la décennie 2014-2025. Comparaison avec la saison 2024-2025. Parmi les soixante-dix-sept espèces dénombrées en 2025 dans les Traicts du Croisic et les marais salants de Guérande, douze ont été sélectionnées et leurs résultats, de 2014 à 2025, sont présentés. La saison 2024-2025 est comparée à la moyenne de la décennie 2014-2024. L’évolution des principales espèces mi-janvier est analysée et discutée. Quatre espèces sont en forte augmentation (Tadorne de Belon, Canard souchet, Avocette élégante et Barge à queue noire), trois en faible déclin (Canard pilet, Grèbe à cou noir et Mouette mélanocéphale) et deux en déclin modéré (Canard siffleur et Courlis cendré). L'influence de ces données sur les résultats départementaux et métropolitains est étudiée. Huit espèces représentent plus de 30 à plus de 98 % des effectifs hivernants en Loire-Atlantique (Bernache cravant, Tadorne de Belon, Grèbe à cou noir, Huîtrier pie, Avocette élégante, Courlis cendré, Barge à queue noire et Chevalier gambette). Le site représente un intérêt national pour l’hivernage de la Barge à queue noire (plus de 19 %).

Les conditions météorologiques au cours de l’hiver affectent peu les variations d’abondance d’une communauté de rapaces en Bourgogne. Les effets des conditions météorologiques ont été étudiés sur les variations d’abondance d’une communauté de quatre espèces de rapaces au cours de l’hiver dans l’Auxois, en Bourgogne, entre 1988 et 2025 (38 ans). Seuls le Faucon crécerelle montre une diminution significative d’abondance au cours de l’hiver et le Milan royal une augmentation. Aucun effet de ces conditions n’a été mis en évidence excepté pour le milan dont les variations d’abondance sont corrélées négativement avec le nombre de jours de gel, de neige et le cumul de neige. Le climat dans l’Auxois n’est pas assez sévère pour générer un effet significatif sur l’abondance des rapaces dont les variations observées sont plutôt à rapporter au niveau des ressources alimentaires, à la mortalité ou à l’émigration. La réponse des espèces aux conditions météorologiques varie en fonction de leur masse et de leur comportement de chasse.

Le Martinet cafre Apus caffer. Récentes observations récurrentes en Tunisie. Le Martinet cafre, espèce afro-tropicale, étend actuellement son aire de distribution estivale vers le Nord du bassin méditerranéen. Des observations récentes en Tunisie attestent d’une présence récurrente, probablement en lien avec les nidifications récemment confirmées en Italie et en Corse. Cette expansion, possiblement favorisée par le changement climatique, fait de la Tunisie une zone de transit et une zone potentielle d’installation.

L’Aigle royal Aquila chrysaetos dans le Sahara Atlantique marocain, aux confins de l’ouest paléarctique. Au Maroc, l’Aigle royal est considéré comme sédentaire rare mais largement répandu dans les zones montagneuses. Si sa répartition et ses effectifs sont relativement bien connus dans la partie nord du pays, les informations dans l’extrême sud restaient fragmentaires. L’analyse bibliographique ainsi que des données récemment collectées dans les confins méridionaux du territoire marocain (Région Dakhla-Oued Ad Deheb) a permis de dresser un état des lieux sur cette espèce dans le Sahara Atlantique, aux confins Sud-Ouest du Paléarctique occidental. Le long de la bande littorale, les habitats favorables à la nidification de l’espèce (massifs montagneux) n’existent pas. Ces types d’habitats commencent à apparaître plus à l’intérieur des terres et la majorité des territoires se concentrent dans les massifs montagneux des zones du Tirs et de l’Adrar. Le chiffre d’une vingtaine de couples est proposé pour l’ensemble de cet immense territoire s’étendant sur 143 000 km2.

Évolution à long terme des populations hivernantes de Bernache cravant à ventre sombre Branta bernicla bernicla de l’estuaire de la Gironde, le cas de la baie de Bonne-Anse. La Bernache cravant à ventre sombre est une petite oie nichant dans la presqu’île de Taïmyr en Sibérie et hivernant sur les côtes de l’Europe tempérée. En France, ces effectifs ont augmenté à partie des années 1970 suite à sa protection et à celle de ses habitats d’hivernage. Au Sud de sa distribution d’hivernage, les effectifs hivernants de Bernache cravant sont suivis depuis 1976 dans l’estuaire de la Gironde, et plus particulièrement dans la baie de Bonne Anse. Les résultats de ce suivi sont présentés et analysés en termes de phénologie, d’âge-ratio, d’évolution des effectifs et d’évolution de la distribution. L’évolution à long terme de la population hivernante de Bernaches cravant de l’estuaire de la Gironde est reliée à l’évolution des habitats (slikke et schorre), l’évolution de la disponibilité en ressources alimentaires et l’indice d’abondance des lemmings. Ces dernières années, l’augmentation des effectifs de bernaches dans la baie de Bonne Anse a entraîné la colonisation progressive d’autres sites en amont de l’estuaire de la Gironde en fonction des ressources alimentaires disponibles. La préservation de la Bernache cravant dans l’estuaire de la Gironde nécessite la prise en compte de l’évolution des habitats littoraux et la protection de ces habitats.

ABSTRACT.– Contribution to the diet of the Little Owl Athene noctua in the Tibesti Mountains/Chad in May 2025. The diet of Little Owls based on pellets collected in May 2025 in the Tibesti Mountains in Chad was studied. 89% of the food remains were of three species of gerbils, while the remaining parts were arthropods, particularly beetles (34,7%), spiders and Solifugae (10.7%). The share of gerbils seems to vary with precipitation. These are the first data regarding the diet of the Little Owl in Chad. RÉSUMÉ.– Contribution au régime alimentaire de la Chevêche d’Athéna Athene noctua dans les monts Tibesti (Tchad) en mai 2025. Le régime alimentaire de la Chouette chevêche a été étudié à partir des pelotes de réjection collectées en mai 2025 dans les monts Tibesti (Tchad). 89 % des restes alimentaires étaient composés de trois espèces de gerbilles, le reste étant constitué d’Arthropodes, notamment de Coléoptères (34,7 %), d’Araignées et de Solifuges (10,7 %). La proportion de gerbilles semble varier en fonction des précipitations. Ces données constituent les premières informations concernant le régime alimentaire de la Chouette chevêche au Tchad.

Actualisation du statut du Flamant nain Phoeniconaias minor en Afrique de l’Ouest. La population de Flamant nain d’Afrique de l’Ouest se situe à près de 5 000 km des effectifs importants d’Afrique de l’Est et y semble implantée depuis au moins la fin du XIXe siècle. Elle ne s’y reproduit cependant qu’occasionnellement. Cette population a augmenté depuis 2013 mais présente d’importantes fluctuations d’effectifs. Hors période de reproduction et de stationnement pré-reproducteur, l’effectif du delta du Sénégal se réduit et il est hautement probable que les oiseaux effectuent des déplacements vers des sites non dénombrés ou se mêlent aux oiseaux d’Afrique de l’Est. Le peu de cas réussis de reproduction en Mauritanie, alors que l’effectif augmente suggère que la population du delta du fleuve Sénégal est renforcé régulièrement par des oiseaux issus d’Afrique de l’Est.

Sous le terme de "flamant" se cache une famille homogène de six espèces qui dispose d'atouts considérables pour séduire: présence sur quatre continents, morphologie extravagante, couleur, taille, vie sociale, nids, manière de barboter, parades, déplacements. Son iconographie, fournie par de multiples sources (sites de musées, galeries d'art, professionnels de vente aux enchères, bibliotheques diverses, presse, banques d'images, etc.), révèle l'ampleur des liens tissés avec les hommes depuis des millénaires. Elle raconte à la fois une histoire naturelle, une histoire de l'art et, plus encore, la fascination des hommes pour cet oiseau devenu ujourd'hui objet de communication.

Defining reference states plays a key role in ecological restoration, guiding management strategies and serving as a benchmark for evaluating ecosystem recovery. However, the choice of reference states is never entirely objective and depends on the context, value-driven approaches, and other numerous criteria such as site history and geographical setting, ecological integrity, or stakeholder interests. To shed light on how reference states are defined, we analyzed 32 restoration projects covering both terrestrial and aquatic ecosystems, monitored between 1999 and 2023 by researchers from the INRAE Ecological Restoration Network (REI, https://restauration-ecologique.hub.inrae.fr ). Our results highlights shared trends in the criteria used to select reference states, while also revealing variable levels of agreement among projects, with notable differences between aquatic and terrestrial projects in terms of stakeholder involvement, selected metrics, and evaluation measures. This study represents a first step before launching a broader survey within the international community. The objective is to further explore the challenges associated with defining reference states, particularly in the context of accelerating global (notably climate) change, and the new EU Nature Restoration Law being implemented across Member States.

Afro-Palearctic migrant populations are declining in Europe, and non-breeding conditions in Africa have been shown to be important in determining the population size of long-distance migrants. Overwintering conditions and prenuptial migration may both influence population growth through direct effects on survival. However, studies examining the impact of environmental factors on species survival remain limited, as this requires data over several years. The Collared Pratincole Glareola pratincola is an insectivorous and strictly migratory wader that nests in grasslands and steppes in Europe and overwinters in savannas, mainly in the Sahel. In this study, we used a 13-year mark–recapture dataset collected at the breeding site in L'Albufera, Valencia (Spain), to estimate annual survival rates of Collared Pratincole. We found a high mean annual survival probability of 0.84 ± 0.01 se, though this varied from year to year. Wet years, as indicated by large maximum floods over the inner Niger delta, the Senegal river and delta, and the NDVI (a remotely sensed measure of vegetation based on primary production) in West Africa, positively affected the survival of the species, explaining respectively 49%, 50% and 62% of the survival temporal variation. Contrary to our prediction, unfavourable winds during prenuptial migration periods were not correlated with survival. Our study supports the hypothesis that drought conditions experienced by migratory birds in the Sahel (e.g. the Great Drought in 1969–1992) may have negatively impacted their populations.

Objectives We aimed to provide a long-term, comprehensive description of Peregrine Falcon Falco peregrinus diet composition and diversity on coastal Mediterranean islands, near a major urban area, at breeding and non-breeding seasons. Methods We identified prey species from 87 remain samples of F. peregrinus preys year-round collected on 6 islands near Marseille, France (1995-2024). Prey relative abundance, biomass, and diversity indices were calculated. Seasonal, spatial, and temporal variations in diversity indices and prey taxa abundances were assessed using Kruskal–Wallis tests and generalized linear models. Results We identified 4,483 prey individuals across 180 species (i.e., species richness), with birds

Calicophoron daubneyi is an emerging rumen fluke of ruminants whose prevalence and geographic range have increased markedly across Western Europe over recent decades. Despite its growing veterinary importance, population-level genetic studies of this trematode have been hampered by the absence of suitable multilocus markers, with previous work relying on mitochondrial or ribosomal sequences that provide limited resolution for epidemiological inference. In this study, we developed and validated the first panel of polymorphic microsatellite markers for C. daubneyi and applied them to assess genetic diversity, clonality, and population structure in natural populations from the eastern French Pyrenees. Using Illumina-based genomic sequencing, we isolated 16 candidate loci, of which 10 robust and polymorphic microsatellites were retained after stringent quality filtering. We used these markers to genotype 187 adult parasites collected from cattle originating from seven localities spanning a maximum pairwise distance of approximately 50 km. Analyses explicitly accounted for the strong clonal amplification characteristic of trematode life cycles. We observed high levels of genetic diversity and a pronounced but variable clonal signal among sites. After attempting to correct for clonality and null alleles, genetic differentiation among populations was low and no significant isolation by distance was detected, consistent with substantial genetic exchange occurring at the regional spatial scale examined. These findings suggest that definitive host movement contributes importantly in shaping parasite gene flow within this interconnected livestock system. By providing the first validated microsatellite toolkit and baseline population-genetic data for C. daubneyi, this study establishes a foundation for future molecular epidemiological investigations of transmission dynamics, host–parasite interactions, and parasite dispersal in European livestock systems.

Vultures are obligate scavengers that have long been regarded as a systematic entity. However, phylogenetic studies show that the scavenging lifestyle evolved in three distinct phylogenetic lineages of raptors [New World Vultures (Cathartidae), Bearded, Palm-nut, Egyptian Vultures (Gypaetinae) and Griffon and Cinereous Vultures (Aegypiinae)]. In particular, the Gypaetinae show a number of special traits (territoriality, bone eating, plant food, cosmetic use) that are absent in other vultures. Whilst New World vultures and Aegypiinae are obligate scavengers and correspond most closely to the functional phenotype “vulture”, the Gypaetinae form a specialised evolutionary lineage in which the utilisation of remains left over from “real meat-eating” vultures is a central theme. Here we review the morphology, breeding biology, behaviour and ecology of vultures in a phylogenetic perspective and map the traits on a phylogenetic tree. Analysing the evolution of traits in vultures and their molecular phylogeny, the 23 species are far from being a monophyletic group. Therefore, it makes no sense to place them in a common taxonomic group. Instead, as more or less specialised scavengers, they form an eco-functional group that has developed common characteristics through convergence due to the same specialisation. Our findings show that the three vulture clades, particularly the group of Bearded, Egyptian and Palm-nut Vultures (subfamily Gypaetinae), differ greatly in their genetics, biology and behaviour. The Gypaetinae, thus, occupy a special place amongst the vultures bridging the gap with typically predatory raptors.

Avian blood parasites are vector-transmitted protozoan parasites and common in wild birds. They cause acute and chronic infections at different life stages with potentially detrimental effects on host fitness. Transmission often happens during the nestling period, when biting dipterans have easy access to featherless skin. However, little is known about patterns of infection within and between broods. Therefore, we investigated prevalence of haemosporidians (Leucocytozoon, Plasmodium and Haemoproteus) in Jackdaw (Corvus monedula) nestlings over four non-consecutive years. Prevalence varied by year, averaged at 33.9%, with Leucocytozoon being the most prevalent genus. We found no links between infection and morphometry, nor with sex or hatching date, at the population level. However, at the brood level, among female nestlings, those with shorter tarsi were more likely to be infected than female siblings with longer tarsi. Infection probability was positively correlated with brood size at the brood level, but not at the individual level. Finally, more broods were partially infected than fully infected or uninfected. Thus, the observed patterns in prevalence were manifold, indicating that haemosporidian infections, caused by bites of vectors, are influenced by various factors in this host–vector-parasite system.

Avian haemosporidian parasites (Plasmodium, Haemoproteus, and Leucocytozoon) are widespread haemoparasites that can impact avian health and fitness. Feral Pigeons (Columba livia domestica) are abundant in urban environments, yet the diversity and prevalence of haemosporidians in this host remain poorly studied, particularly in Europe. This study assessed the prevalence, genetic diversity, and morphological characteristics of haemosporidian parasites in 40 Feral Pigeons sampled from two sites in Lisbon, Portugal. It represents the first application of an integrated molecular and microscopy approach to haemosporidian research in Portugal. All individuals were infected with Haemoproteus columbae, and four distinct lineages were detected (COLIV03, COQUI05, CXNEA02, HAECOL1), all corresponding to this morphospecies, representing new geographic records for Portugal. Moreover, all lineages (except HAECOL1) were reported for the first time in Europe. Morphological examination, together with phylogenetic analysis and low genetic divergence (0.21–0.64%) from reference lineages, supported the assignment of lineage CXNEA02 to H. columbae, establishing its vertebrate host and morphospecies for the first time. Parasitaemia ranged from 0.05% to 8.11%, spanning infection intensities from low (≤ 1%) to high (> 5%) levels, and showed only a weak association with host body condition. In contrast, the presence of double gametocyte infections (DGIs) emerged as a significant predictor of reduced body condition, independent of parasitaemia, indicating increased physiological costs to the host. Male–female DGIs were detected exclusively within the dominant lineage HAECOL1, suggesting a potential role of this infection pattern in transmission dynamics and contributing to the exceptionally high prevalence observed in this system. The combined use of PCR and microscopy enabled the identification of molecular and morphological false negatives, the linkage of genetic lineages with morphospecies, and the identification of biologically meaningful infection traits not detectable by molecular screening alone. These findings underscore the underexplored diversity of avian haemosporidians, even in highly abundant host species, and highlight the value of integrated methodological approaches for avian parasite ecology.

Avian malaria parasites and related haemosporidians include a highly diverse group of parasites infecting wild birds worldwide, with variable knowledge depending on bird taxa. Although comparatively less studied than terrestrial species, avian malaria infections in seabirds are generally rare, a pattern attributed to several non-mutually exclusive hypotheses, including limited exposure to vectors and differences in host life history traits. Here, we screened blood parasites by combining molecular detection and observation of blood smears in the highly endangered Bermuda Petrel (Cahow) Pterodroma cahow, sampled during the 2022 breeding season (January–April). In addition, we quantified the blood cell types to provide baseline information on the immunological status of this species. Furthermore, few blood samples of the White-tailed Tropicbird Phaethon lepturus catsbyii breeding in sympatry on the same archipelago were also analyzed for parasite presence. Our results support the absence of blood parasites of the genera Plasmodium, Haemoproteus, and Leucocytozoon as well as filaroid nematodes. The absence of blood parasite infections in both species may reflect low exposure to vectors in offshore marine and terrestrial environments, although other explanations, such as the absence of parasites able to infect these host species, are also possible. We found no significant differences in the relative abundance of monocytes among islets, although differences were observed, and a significantly higher total abundance of leucocytes in female Bermuda Petrels than males. Differential parasite exposure among islets and differential life history traits between sexes could account for these results. Negative records of parasite infections in wild birds, including endangered species, are essential for accurately characterizing global infection patterns and understanding host–parasite associations in avian communities.

Re-nesting within the same breeding season after clutch loss is very rarely observed in large raptors, including the endangered greater Spotted Eagle (Clanga clanga). Here, we describe the first well-documented and confirmed case of clutch replacement in this species, observed in 2024 in the Biebrza Basin (NE Poland). Using modern telemetry, camera trapping technologies, and individual marking, we tracked an adult female that abandoned her first clutch due to disturbance caused by a swarm of insects. After an energy-replenishing period of abundant foraging, the female re-nested with the same male had previously bred with and successfully raised a chick in a different nest. This unprecedented event in this species underscores how the combination of early clutch replacement, sufficient food resources, and nest availability can enable re-nesting, and how such conditions may be relevant for the conservation of this threatened species.

Pathogens can shape host ecology and evolution by influencing survival, reproduction, and the expression of sexually selected traits. Among avian pathogens, haemosporidian parasites (Plasmodium, Haemoproteus, and Leucocytozoon) are widespread and frequently assessed for their impacts on host–parasite interactions. Susceptibility to infection is expected to vary with host sex, age, temporal dynamics, genetic diversity, body condition, and sexually selected traits, yet empirical evidence from longitudinal studies in wild populations remains limited. Here, we studied haemosporidian infections in Blue-black Grassquits (Volatinia jacarina), a Neotropical passerine characterized by sexual dichromatism and conspicuous courtship displays in males. Across three breeding seasons in central Brazil, we sampled 98 males and 53 females, combining morphological, behavioral, and genetic data with molecular screening of parasites. Parasite lineages were identified and assigned to the genera Plasmodium and Leucocytozoon using phylogenetic inference. Some detected lineages extend the previously known geographic distributions of these parasites. Parasite occurrence did not differ between sexes or years. Longitudinal sampling revealed that, among individuals that acquired infections, some became PCR negative after an initial positive result, whereas others remained PCR positive across breeding seasons, indicating that infections are dynamic rather than uniformly chronic. Contrary to expectations, parasite occurrence did not correlate with body condition, molt progression, heterozygosity, display rate, or pairing success. These results indicate no detectable associations between parasite occurrence and the measured indices of body condition, ornamentation, display behavior, or pairing success. Our findings highlight the value of publishing longitudinal results, which temper assumptions of universally high parasite costs and thus foster a more nuanced understanding of host–parasite dynamics in natural populations.

Colourful plumages may bear high production and maintenance costs. The parasite hypothesis posits that visual signals work as honest indicators of heritable resistance to parasites. However, the value of structural and melanin-based colours as honest signals is still an open question awaiting evidence, especially in lekking species, for which sexual selection is supposedly more intense than in socially monogamous species. In this context, we sampled 24 adult male and 26 adult female Blue-capped Manakins (Lepidothrix coronata) from a population in central Amazonia to test the hypothesis that (i) plumage colour of male Blue-capped Manakins influences the attraction of female individuals; and (ii) the occurrence of haemosporidian parasites is associated with the plumage colouration patterns of Blue-capped Manakin. We estimated the frequency of female visits at individual perches of Blue-capped Manakin males through behavioural observations, measured colour spectra from eight plumage patches of male and female individuals, and examined whether these individuals were infected with haemosporidian parasites using molecular screening techniques. We found that variation in melanin-based pigment and structural colours amongst male Blue-capped Manakin was associated with female visits. However, variation in these colours did not correspond to the occurrence of haemosporidian parasites. In contrast to previous studies, we suggest that the structural and melanin-based colouration of male and female Blue-capped Manakin may not be costly enough to be used as an honest signal of susceptibility to haemosporidian parasites.

Avian haemosporidians are common vector-transmitted parasites that infect birds. Although avian haemosporidians have been studied extensively in songbirds, less is known about haemosporidian prevalence in raptors, particularly in the United States. We used molecular methods to test blood samples collected from raptors at five wildlife rehabilitation centers across the United States for avian haemosporidians. We identified parasites from the genera Haemoproteus, Leucocytozoon, and Plasmodium using a multiplex PCR and determined prevalence by raptor host species and site. Almost half of the raptors tested (47%) were infected with at least one parasite, with Plasmodium detected at the highest frequency (28%) followed by Haemoproteus (21%), and Leucocytozoon (12%). Prevalence of each parasite genus varied among host species. For example, Haemoproteus prevalence was higher in American Kestrels (Falco sparverius; 55%), Barred Owls (Strix varia; 58.2%), and Great-Horned Owls (Bubo virginianus; 43.8%) than in Bald Eagles (Haliaeetus leucocephalus; 0%) or Black Vultures (Coragyps atratus; 0%). Prevalence also varied among sites for all three parasite genera. However, we did not detect a species by site interaction effect for prevalence, suggesting that relative rates of parasite infection among raptor species are relatively constant across the region we investigated. This work adds to our understanding of raptor disease ecology at a regional geographic scale. Future analyses will focus on the diversity and distribution of parasite genetic lineages among these host species and sites.

In their seminal hypothesis, Hamilton and Zuk proposed parasites to drive host sexual selection and predicted infections to correlate with ornamentation. Since then, a plethora of studies has explored how parasite occurrence relates to host traits, though the underlying assumption that parasite infection parameters are host-specific traits has rarely been evaluated. We used a global database (MalAvi) on avian haemosporidian parasites to 1) derive parasite prevalence and diversity estimates, 2) quantify how host species-specific these two infection parameters are, 3) test if our parameter estimates correlate with historical values derived by light microscopy and bird brightness scores, and 4) discuss how our findings affect tests of species-level hypotheses like the Hamilton–Zuk hypothesis. We found only moderate repeatability in parasite prevalence and lineage diversity when estimated from independent study locations. Nevertheless, prevalence values assessed by PCR in MalAvi database studies significantly correlated with historical prevalence estimates assessed by microscopy. Compared to the historical microscopy-derived estimates, prevalence and diversity estimated from MalAvi were not significantly related to bird brightness scores. Based on our results, we conclude that other factors than those related to host species might shape most of the variation in haemosporidian infection parameters, a fact that should be considered when testing species-level hypotheses in an interspecific framework.

Vector-borne diseases (VBDs) have long been recognized as sensitive indicators of environmental conditions, and historical records reveal that associations between climate, landscape, wildlife, and disease have shaped human understanding of epidemics for centuries. In the context of accelerating global environmental change, this perspective has gained renewed relevance as climate warming, land-use transformation, and urbanization increasingly alter interactions among hosts, vectors, and pathogens. Birds and their haemosporidian parasites (Plasmodium, Haemoproteus, and Leucocytozoon) have emerged as powerful sentinel systems for detecting these changes because they are widely distributed, ecologically diverse, and supported by extensive long-term datasets. Here, I synthesize evidence demonstrating how avian malaria systems reveal climate- and landscape-driven shifts in parasite prevalence, transmission intensity, and geographic range across broad spatial and temporal scales. Long-term and large-scale studies show consistent associations between rising temperatures and increased haemosporidian transmission, including altitudinal and latitudinal range expansions into previously unsuitable environments. Complementary research highlights how habitat fragmentation, deforestation, agricultural intensification, and urbanization modify vector communities, host condition, immune function, and parasite assemblages in context-dependent ways. While these findings underscore the sensitivity of avian host–parasite systems to environmental change, they also reveal important limitations to extrapolation, including non-linear transmission dynamics, parasite- and host-specific responses, and the frequent lack of long-term vector data. I argue that birds and their haemosporidian parasites provide robust early-warning indicators of environmental change when interpreted within an integrative framework that accounts for ecological heterogeneity and socio-environmental context, strengthening their value for anticipating emerging VBD risks under ongoing global change.

Spanish Sparrows in the Western Palaearctic show different migration strategies that might affect haemosporidian parasitism. In a migratory Croatian population, haemosporidian prevalence averaged at 39.8%, with low parasitemia and low parasite diversity dominated by two Haemoproteus and one Plasmodium lineage. Comparative data from six host populations revealed higher net infection prevalence in resident (60%) compared to migratory populations (40%), wherein the strategy dependency was caused by the genus Plasmodium. Genus-specific prevalence of Haemoproteus or Leucocytozoon did not vary coherently with migration strategies. In total, 32 haplotypes have been recorded so far (16 Plasmodium, seven Haemoproteus, and nine Leucocytozoon lineages). Chronic infections were dominated by three lineages (h-PADOM05 in 34.1%, h-PADOM23 in 17.4%, and p-SGS1 in 12.6% of records), while 19 lineages were detected only once (78% of Leucocytozoon, 69% of Plasmodium and 14% of Haemoproteus lineages). Genetic parasite diversity did not show a consistent pattern with migration strategy, but haplotype diversity was high at local scales, i.e. in resident sparrows of Sardinia and migratory hosts in Bulgaria. Chao´s dissimilarity indices of 0.79–0.93 for resident and 0.72–0.91 for migratory populations pointed to a high degree of site-specificity in parasite compositions. Thus, migration can influence haemosporidian prevalence in Spanish Sparrows, but parasite diversity or lineage composition appears to be determined by conditions at population-specific sites of residency.

Haemosporidian parasites can alter host immune and physiological condition, yet their hematological effects may depend on habitat disturbance and seasonality. We investigated how haemosporidian infection relates to hematological parameters of common understory birds across a land use gradient in tropical montane cloud forests of central Veracruz, Mexico. During 2013–2014, we sampled six abundant passerines across five land use types (conserved forest, peri-urban forest, urban forest, shade coffee plantation, and cattle field). Infections were assessed by microscopy and PCR, and hematological parameters (differential leukocyte proportions, H/L ratio, total leukocytes, thrombocytes, and polychromatophils) were analyzed with generalized linear mixed models using total haemosporidian abundance (parasites per 10,000 erythrocytes) as the primary infection predictor; genus-specific analyses (Plasmodium vs Haemoproteus) were used as secondary complements where sample sizes allowed. Overall infection prevalence was 61%, and infection rate varied among host taxa and habitats. Total parasite abundance was frequently higher in disturbed habitats, particularly for Plasmodium, whereas Haemoproteus sometimes peaked in conserved or shade coffee plantations, indicating genus and host-specific patterns. Several hematological parameters varied across land use types and seasons, with both baseline habitat effects and context-dependent associations with parasite abundance. Sex-specific associations with parasite infection occurred for selected parameters (including eosinophils, polychromatophils, and thrombocytes), and the migratory Wilson’s Warbler showed habitat dependent responses. These results show that land use, seasonality, and host traits jointly shape hematological responses to haemosporidian infection in a disturbed cloud forest landscape, with outcomes contingent on parasite genus and host identity.

Migratory birds are among the most threatened animals globally. Environmental drivers of bird distributions outside the breeding grounds, particularly in the tropics, remain poorly known. We assessed the year-round habitat suitability for the Sociable Lapwing (Vanellus gregarius), a critically endangered, long-distance migratory bird that moves between Central, West, and South Asia. We combined annual bird occurrence data from a historical records database and satellite tracking, with environmental metrics from Landsat satellite imagery for the period 1990–2024. We trained a multi-temporal random forest model to predict species occurrence as an indicator of primary productivity, surface moisture, vegetation openness, and terrain ruggedness over 34 years. Across the range, the overall habitat suitability, i.e., the probability of occurrence predicted from species distribution model, increased through the annual cycle over the study period. On the breeding grounds, habitat suitability increased in the dry steppe and meadow steppe of Kazakhstan. At the stopover locations, irrigated cropland in the coastal areas, drylands, and deserts, as well as cultivated floodplains of larger rivers, were predicted to be of high suitability. Some of the largest gains in habitat occurred on the wintering grounds in western India and eastern Africa, where suitability increased in semi-arid mosaic landscapes comprising subsistence agriculture and savannas. Our results suggest that although the habitat suitability across the Sociable Lapwing range has increased over the past 3 decades, this has likely not contributed to an increase in Sociable Lapwing numbers, which continue to decline globally. Future research should, therefore, focus more on surveys outside breeding range including GPS tracking, and close monitoring of agricultural land-use change supported by satellite remote sensing.

Host relatedness has been hypothesized to cause similarities in parasite assemblages and prevalence; we investigate this hypothesis in the ecologically diverse Caucasus Mountain region. Three Phylloscopus species sampled between 1998 and 2014 were analyzed to determine infection rates and to investigate whether P. collybita had low infection rates when compared to two congeners (P. nitidus and P. sindianus), as has been suggested. Generalized linear models were utilized to determine whether any differences in infection rates were related to environmental differences among sampling locations. Phylloscopus collybita and P. nitidus had comparable infection rates across and within haemosporidian genera; however, P. sindianus had distinctly lower infection rates. Models indicated that these infection differences were the result of differences between avian host species, rather than being influenced by other factors (e.g., host characteristics or environment). Results suggest that the host-relatedness hypothesis does not apply to here. Low haemosporidian infections rates of P. sindianus could be attributed to a higher elevational distribution, which may reduce contact with vector populations. One novel lineage was recovered from a P. nitidus individual in Armenia. This novel Haemoproteus lineage is similar in haplotype to another previously identified lineage found infecting P. trochiloides in India.

Island ecosystems such as those in Madagascar host a highly endemic biodiversity which is strongly shaped by geology, habitat structure, altitude, and anthropogenic impact. These factors could further shape the prevalence and diversity of avian haemosporidian parasites (Haemoproteus, Plasmodium and Leucocytozoon). To assess how contrasting habitats affect shifting patterns in parasite prevalence and lineage richness, we examined samples from three widespread Malagasy bird species: Cinnyris sovimanga (Nectariniidae), Hypsipetes madagascariensis (Pycnonotidae), and Terpsiphone mutata (Monarchidae) across two ecologically distinct environments: the mid-altitude rainforest of Maromizaha (800–1200 m) and the oceanic island of Nosy Saba (at sea level). Of the 167 blood samples analysed, 50.9% were positive for haemosporidian parasites using molecular methods, whereas 56.3% of 119 blood smears were positive using morphological methods. In total, twenty-five distinct haemosporidian lineages were identified. The Maromizaha rainforest harboured a higher lineage diversity and prevalence of Haemoproteus and Leucocytozoon, consistent with its structurally complex habitat composition. In contrast, Nosy Saba Island harboured higher Plasmodium prevalence (95.4%), likely reflecting a greater abundance of mosquito vectors in a structurally simple habitat. Yet, Plasmodium lineage diversity was higher in Maromizaha, suggesting that vector abundance does not necessarily translate into vector diversity. These findings show a likely influence of habitat structure and vector ecology in shaping haemosporidian parasite infections. While humid, continuous forests support greater parasite diversity, degraded island habitats may favor dominance by generalist lineages. Future studies combining vector sampling with host–parasite data will be essential for understanding transmission dynamics across contrasting habitats, especially across Madagascar’s heterogeneous landscapes.

Avian malaria, caused by Plasmodium parasites, commonly persists as a chronic infection, yet reliable treatment protocols remain insufficiently evaluated. Assessing treatment efficacy is essential for improving disease management and understanding impacts on host health. We conducted a 2.5-year experimental study to assess the efficacy and safety of atovaquone-proguanil (Malarone®) against Plasmodium relictum (genetic lineage pSGS1) in canaries (Serinus canaria domestica). Seventy-six birds were assigned to four groups: experimentally infected and treated (E1), infected and untreated (E2), uninfected and treated (C1), and uninfected and untreated controls (C2). Following blood inoculation, birds in groups E1 and C1 received four treatment cycles over two months. Parasitemia was monitored by microscopy and PCR for 981 days, and survival, body mass, and biochemical parameters were assessed to evaluate long-term effects. We hypothesized that Malarone would clear blood stages, but that recrudescence might occur due to persistent exo-erythrocytic stages.Malarone treatment resulted in rapid elimination of parasitemia in E1 birds, with no relapses detected by microscopy or PCR during follow-up. In contrast, untreated infected birds exhibited persistent low-level and recurrent parasitemias. Survival did not differ among groups, and most physiological parameters remained within reference ranges. Transient increases in total protein and creatine kinase occurred only in untreated infected birds, indicating limited physiological impact of chronic infection and no detectable long-term toxicity of the treatment. Our results demonstrate complete and sustained clearance of P. relictum (pSGS1) following prolonged Malarone treatment. The absence of relapse suggests limited exo-erythrocytic persistence or effective suppression, supporting the safe and effective use of this drug for avian malaria.

In wild animal populations, the prevalence of vector-borne parasites can be a serious threat if derived in disease, but extreme environments can act as natural refuges by restricting the presence of vectors and, consequently, reducing the transmission of vector-borne parasites. The Andean Condor (Vultur gryphus), a key scavenger of ecological significance and flagship conservation status, inhabits high-altitude regions where abiotic factors may limit parasite transmission. Little is known about the prevalence of blood parasites in this species. In this study, we examined the presence of haemosporidian parasites (Plasmodium, Haemoproteus, and Leucocytozoon) in Andean Condors from both wild healthy and rehabilitating, and captive populations in Argentina. Blood samples were analyzed by blood smears examination and by using nested-PCR protocols targeting cyt b from parasite DNA. Of the 33 condors sampled, only two individuals tested positive for Plasmodium (Lineage ZEMAC01 and PADOM09), a wild adult male from Tucuman and a wild juvenile male from San Luis, sampled on the day of admission at Buenos Aires Zoo. These results may reflect the environmental conditions associated with high-altitude ecosystems, where low temperatures and other abiotic factors can limit the presence of vectors responsible for transmitting blood parasites. The detection of Plasmodium in wild condors raises concerns about potential pathogen introduction into recovery centers via admitted individuals, emphasizing the need for biosecurity protocols to prevent the spread of potential harmful pathogens in captive populations of endangered species. Given the increasing threats posed to this species, continuous monitoring of both wild and captive populations is recommended to detect emerging health risks and support effective conservation strategies.

After expanding their range from the Netherlands to Germany, introduced Egyptian Geese (Alopochen aegyptiaca, Tadornini) started to breed in Germany in 1981. Egyptian Geese are well-adapted to an aquatic lifestyle, which brings them into close contact with some of the vectors of avian malaria, such as biting insects in the order Diptera. As research on avian malaria in Anseriformes remains scarce in Europe, the prevalence and diversity of haemosporidians in Egyptian Geese were analyzed in 62 blood samples taken from 14 adult and 48 juvenile birds in Stuttgart, southwestern Germany. Blood was collected during the annual capture of family groups. The samples were tested for Plasmodium, Haemoproteus and Leucocytozoon using the nested PCR protocol developed by Hellgren et al. (2004). Surprisingly, none of the sampled geese tested positive for haemosporidian parasites, despite infections being observed in Egyptian Geese in their native range.

During an infection, the genetic composition of the pathogen population in the host might range from clonal to genetically diverse, depending on the genetic variation of the inoculum, mutation events, genetic drift, and host selection during the course of the infection. Variation in the genetic diversity of avian malaria parasites, both within and between individual hosts, is not well documented. To shed light on this, we used avian malaria to investigate how changes in the predominant haplotype varied between infection events and also within single infections over time. This was done by experimentally inoculating nine birds with the blood of one bird infected with Plasmodium relictum (lineage SGS1), and sequencing 1.03 Mb (13%) of the parasite exome before and after peak infection. In each infected bird, different haplotypes became established and changed in relative frequency over time. Several birds did not effectively suppress parasitemia, and we identified exclusive non-synonymous SNPs in gene families with functions related to immune evasion and host cell invasion in those infections, suggesting that some haplotypes might be harder for some individual hosts to suppress than others. We speculate that these haplotypes existed at low relative frequencies in the donor bird, but only increased in frequency (i.e., became runaway haplotypes) in a subset of susceptible host individuals. Alternatively, those SNPs might represent novel mutations that appeared independently in only a subset of host individuals. Deeper sequencing of the initial inoculum and the infections in all host individuals would be required to distinguish between these two hypotheses.

This study tested a hypothesis regarding behavioral coordination in breeding behavior of Streaked Shearwater Calonectris leucomelas: the “chick development hypothesis,” which posits that coordination enhances chick growth via improved provisioning. As an additional supportive hypothesis, we examined whether highly coordinated pairs may exhibit longer nest stay durations, which contributes to the maintenance of coordination. Using an automated recording system, we quantified coordination with the φ−coefficient and assessed its relationship with reproductive performance through provisioning and nest attendance metrics. We found that higher parental coordination was associated with fewer extended nest absences, potentially reducing periods of prolonged chick fasting; however, while provisioning rate significantly enhanced chick growth, coordination itself did not directly affect chick growth rate. Notably, coordinated pairs exhibited significantly longer nest stay durations, supporting the supportive hypothesis. These results clarify that behavioral coordination is associated with both longer parental nest stays and fewer extended absences, demonstrating that its supplementary effects extend beyond direct relationships to chick growth.

Migratory birds are exposed to a diverse fauna of parasites and vectors throughout their annual cycle, which can potentially facilitate disease transmission across wide geographic ranges. However, few studies have examined how these pathogenic organisms affect the immune profiles and body condition of avian hosts while they are refueling at stopover sites. Here, we used molecular barcoding and microscopic examination to detect, quantify, and identify haemosporidian parasites in Chilean Elaenias (Elaenia chilensis) during their migration stopover in the Serra do Mar, Brazil. We then evaluated whether haemosporidian infections were associated with immunological condition (heterophil, lymphocyte, and H/L ratios), body condition, and fat storage. Among the 79 adult Chilean Elaenias captured, 26 were infected with haemosporidian parasites. However, most individuals carried extremely low parasite burdens during migration. Contrary to our expectations, haemosporidian infection did not affect body condition or fat storage in migrating Chilean Elaenias, regardless of host sex. Likewise, the absence of a relationship between immunological parameters and parasite presence suggests that haemosporidian parasitism does not significantly impact the immune response of these migrating birds. Moreover, the condition of chronically infected and uninfected Chilean Elaenias did not differ, suggesting that these parasites may not constrain host arrival at the stopover site in Serra do Mar.

Goose farming is gaining importance due to the economic value of meat and by-products; however, despite frequent reports of Plasmodium spp. infections in waterfowls, data on systemic biochemical responses in domestic geese remain limited. This study investigated biochemical alterations associated with natural Plasmodium spp. infection in Anser anser domesticus, focusing on acute phase proteins (APPs), thiol–disulfide homeostasis (TDH), and serum protein profiles. Blood samples were collected from geese with Plasmodium infection defined by combined microscopic examination and PCR (n = 35) and from uninfected geese (n = 20) Serum levels of APPs [Serum amyloid A (SAA), haptoglobin (Hp), total sialic acid (TSA)], TDH parameters [Native thiol (NT), total thiol (TT), disulfide (DS)], and serum proteins (total protein, albumin, globulin) were analyzed. Plasmodium-infected geese showed significantly higher levels of APPs than uninfected geese, indicating a strong acute phase response. Meanwhile, thiol components (TT, NT, DS) were significantly lower in Plasmodium-infected geese, reflecting infection-associated oxidative stress. However, redox ratios remained stable, suggesting preserved redox balance through compensatory antioxidant mechanisms. No significant differences were observed in serum protein concentrations. Correlation analysis revealed that Hp positively correlated with DS and negatively with NT/TT%, highlighting an interaction between inflammation and oxidative imbalance. Principal component analysis (PCA) showed that multivariate differentiation between infected and uninfected geese was mainly associated with protein-related and thiol-based redox parameters. In conclusion, Plasmodium infection triggers a distinct inflammatory and oxidative response in domestic geese, without affecting total serum protein levels. The combined use of APPs and TDH markers provides a promising non-invasive approach for monitoring infection-related physiological responses in avian malaria, supporting their potential utility in veterinary practice.

Host–parasite interactions can shape avian population dynamics, and blood parasites can serve as useful markers of host movements across transmission landscapes. Eleonora’s Falcons (Falco eleonorae) occupy multiple biomes annually and, owing to their long-distance migration and unusual late-season breeding, may encounter diverse haemosporidian parasites. Until now, the haemosporidian assemblage of eastern populations had not been analyzed by DNA studies. We examined 321 individuals from two islands in southern Greece hosting a substantial number of breeding pairs in the country (Antikythera: 2017–2024, Paximada: 1991–2001) using nested-PCR amplification and Sanger sequencing to identify haemosporidian infections. Overall haemosporidian prevalence was 15%, with 11 distinct lineages detected. Infection probability did not differ by sex, color morph, or season or sampling period. Nestlings were not infected, supporting the absence of local transmission in the species’ exposed marine cliff-breeding habitat. Several lineages (e.g., pLK05, pLK06, hBUBIBI01, hBUTBUT04, and lCIAE02) matched those previously reported from western populations, suggesting shared transmission areas along shared stopover sites and/or wintering grounds in Africa. Other lineages—such as Haemoproteus tinnunculi hFALSUB01 and the Leucocytozoon lineage lBNOW04—are newly documented in Eleonora’s Falcons and appear more common in eastern populations, indicating acquisition in regions used predominantly during the pre-breeding period. Rare singletons (pRTSR1, pACCTAC01, pSYBOR10, and hPADOM03) may represent spill-over or low-intensity infections acquired at Mediterranean or African sites. Our findings show higher lineage diversity than documented in Spain and highlight how information on haemosporidian assemblages and population-specific transmission areas can complement each other and refine our understanding of host–parasite connectivity across continents.

Collecting GPS positions on bird movements requires secure and efficient attachment methods that maintain animal welfare. For seabirds, one of the most threatened bird groups globally, non-permanent attachment methods are often preferred in short-term studies due to their lower risk of injury, feather damage, or long-term behavioral disruption. However, most available non-permanent solutions, such as tape or temporary adhesives, fail to stay attached for extended periods, often resulting in device loss within days or weeks. Here, we present a novel 3D-printed clamp design for attaching small solar-powered GPS devices to seabirds. The clamp and device were attached to the bird's feathers using only glue, with the clamp specifically designed to interlock with the device. This interlocking mechanism effectively sandwiches the feathers between the clamp and the device, ensuring a secure connection through the use of glue. The clamps were designed to maximize solar panel exposure and minimize premature detachment. We deployed 86 GPS devices on six seabird species across seven locations in Norway from 2023 to 2024, using device-specific clamp variants for attachment to mantle or tail feathers. Devices remained attached for an average of 39 days on mantle feathers (77 birds) and 77 days on tail feathers (four birds), providing sufficient deployment durations to monitor key life stages, such as incubation and chick-rearing. The weight of the clamp structure ranged from 0.5 to 3.2 g, depending on the variant, and emphasis was placed on keeping the total attachment weight as low as possible. The clamps were low-cost, easy to produce using standard 3D printers, and allowed adjustments during application. Our method offers a practical alternative to conventional glue or tape mounts, enabling longer device retention, optimal solar charging, and improved data recovery without resorting to permanent attachment methods such as harnesses. It is particularly well suited for short-term tracking applications over a few weeks to months, such as studying foraging behavior, molt timing, or seasonal movements. Overall, the clamp-based attachment system offers a practical and reliable method for short-term seabird tracking, improving data quality while minimizing impact on the birds.

The ongoing global biodiversity loss is a major challenge of our time. It affects all groups of organisms, but is particularly well documented in birds. The Citril Finch Carduelis citrinella, one of the few bird species endemic to Europe, is one example currently suffering from substantial population declines. We here set out to document its population development over the past 14 years (records in 2011 and 2025) in a part of the Bavarian Alps and to identify the environmental factors being crucial for the occurrence of the species. In our study area around Garmisch-Partenkirchen, the Citril Finch has declined by about 48% between 2011 and 2025. Currently occupied territories, as compared to former territories or control sites, were characterised by a richer supply of flowers, particularly of the Asteraceae family, higher numbers of solitary trees, and a concentration on south-facing slopes. Moreover, areas with stable rather than declining populations showed a shorter distance to the nearest water source, a higher proportion of Mountain Pine, and a longer distance to forest edges. These findings indicate negative impacts of reduced grazing intensity and climate change (drought periods). Our results highlight that preserving the Citril Finch’s alpine habitats depends strongly on traditional, low-intensity farming and appropriate pasture care to maintain the necessary flower-rich, open to semi-open habitats with solitary trees. Providing supplementary water sources would help to counteract the increasing water shortage caused by climate change. Given the documented population decline, targeted conservation measures in the Bavarian Alps, the species’ stronghold in Germany, are urgently needed.

An assessment of the utility of deploying trail cameras to describe the timing of breeding and habitat selection by Corncrakes. To estimate the hatching dates of broods of Corncrake chicks, and the timing of occurrence of juvenile birds, and to compare the intensity of use of two distinct habitats. Trail cameras deployed in and adjacent to agricultural grassland managed for silage production and livestock grazing captured images of Corncrakes. Young of the year were aged using plumage characteristics. Hatching dates and the timing of breeding were compared with expectations from a previous simulation modelling study based on radio-tracking, and observations of broods during mowing. Intensity of use (calculated as the number of days on which images were obtained per day of camera deployment) was compared between previously-mowed, initially short, habitat and taller early cover habitat. Timing of breeding indicated by the camera study was broadly similar to that expected from previous studies using other methods. The intensity of use of early cover habitat by young of the year remained higher throughout summer than that of initially short habitat, even though the latter increased in height substantially during the breeding season. Trail cameras have considerable potential for studies of the timing of breeding and habitat selection by Corncrakes, whose chicks and females are difficult to mark with tracking tags, and whose secretive habits make searching for nests and broods and other direct visual monitoring methods impractical. This approach could be applied to other species with secretive habits. The design of camera surveys, including ours, would benefit from improved stratified sampling and optimisation of camera densities in different habitats. Preliminary results suggest that Corncrake conservation would benefit from increasing the proportion of land that is managed to produce tall, early cover vegetation, rather than grassland mowed for silage.

Systematic recording of marine mammal strandings provides useful data on species occurrence, distribution, abundance, and threats, especially in regions with limited information like southern Iran. This study reports on strandings data collected by the Iran National Stranding Network across four coastal provinces bordering on the Persian Gulf and Oman Sea over the ten-year period from 2010 to 2020. A total of 167 stranding events involving 177 individuals were documented, comprising 14 marine mammal species: 11 odontocetes, two mysticetes and a dugong. The most commonly stranded species was the Indo-Pacific finless porpoise (Neophocaena phocaenoides) (n = 38), followed by Indo-Pacific bottlenose dolphins (Tursiops aduncus) (n = 23), and Indian Ocean humpback dolphins (Sousa plumbea) (n = 23). The greatest number of strandings occurred in the Hormozgan (47%) and Bushehr (37%) provinces, which have the longest coastlines. Stranding reports were nearly twice as frequent during the colder boreal winter (October–March) than the warmer spring and summer months (April–September). Over 65% of the records with enough information to allow analysis (n = 104/167) bore signs of fisheries interactions. Given the challenges of conducting boat-based research in Iran, stranding data are invaluable for understanding marine mammal populations, and expanding the stranding network is crucial for conservation efforts.

The Water Rail breeding population at the Tay Reedbeds, eastern Scotland, is partially migratory. To investigate the migratory and breeding behaviours of Water Rails in Scotland’s Tay Reedbeds. Light-level geolocators were used to estimate migration timing, identify non-breeding locations and infer breeding behaviour of nine individuals from ten recovered geolocators over a six-year period. Five breeding birds remained resident year-round, two migrated to Ireland for the winter (including one individual tagged in two years that migrated in both), and two additional birds arrived from north-east Europe to winter in the Tay Reedbeds. Based on incubation periods of ≥19 days as an indicator of success, ten of 15 incubation attempts (67%) were successful. Among the ten bird-years (n = nine individuals, with one bird monitored across two years), 50% of breeding birds were single-brooded, 10% were double-brooded, 20% made a second breeding attempt after a failure, 10% made two failed attempts before a successful one, and 10% made a single unsuccessful attempt. The results indicate that the breeding population of Water Rails in Britain, previously considered resident, is partially migratory. Light-level geolocators can provide valuable insights into breeding ecology, particularly for species where direct observation is challenging.

Long-term monitoring of marine organisms remains scarce in the Mediterranean Sea, particularly in the eastern Mediterranean basin, resulting in limited knowledge of temporal variation in batoid diversity and population characteristics. To address this gap, seasonal sampling was conducted using a commercial trawling vessel at 10 m and 20 m between the years 2012–2024. Over this 13-year period, a total of 1226 individuals belonging to 10 batoid species were examined. Dasyatis pastinaca (37%) and Gymnura altavela (30%) were the dominant species while Torpedo nobiliana was represented with only 8 (0.7%) individuals. Overall, approximately two thirds of all male and female individuals were captured at 10 m and 20 m, whereas species of the family Myliobatidae were more frequently recorded at 20 m. In general, species diversity did not differ consistently between the two depth contours, as species absent from one depth in a given year could be recorded at the other depth or in subsequent years. These findings provide one of the few long-term accounts of batoid assemblages in the eastern Mediterranean and offer new baseline information on the diversity and population characteristics of batoids in Iskenderun Bay, a coastal system undergoing continuous environmental change.

The invasiveness risk of 15 non-native freshwater fish species established in the lower Tigris Basin (south-west Iran) was evaluated for Shadegan International Wetland and associated catchments of the rivers Jarrahi and Karun by integrating risk screening with species distribution modelling. Risk identification under both current and projected climate conditions indicated that most species pose elevated invasion risk, with 13 species ranked as high risk and two as medium risk under the Basic Risk Assessment, and 11 as high risk, three as medium risk, and one as low risk after incorporating climate change effects. The highest scoring species were redbelly tilapia Coptodon zillii, blue tilapia Oreochromis aureus, and Nile tilapia O. niloticus, each with outcome scores exceeding 40 under both screening components. Distribution models for these species showed good predictive performance and indicated broad climatic suitability across the lower basin, with projections based on non-native occurrences suggesting a substantially wider potential distribution than projections based on native range data. Collectively, these findings indicate a high likelihood of continued spread and ecological impact within this internationally important wetland system and support the need for coordinated transboundary management to strengthen monitoring, early detection, rapid response, and strategic control of potentially invasive species.

Upper Teesdale in northern England supported 1,764 pairs of Eurasian Curlews (95% CL: 1,486–2,145), representing approximately 3% of the UK population; successful breeding and repeat counts indicated recent stable numbers. To estimate breeding numbers by extrapolating from habitat-specific densities, nesting success (including three other wader species) from camera traps and population status from repeat counts. Birds were surveyed using transect-based methods in six habitat types within 114 1 km × 1 km grid squares. Linear densities estimated from transects in each habitat were converted into areal densities by comparing transect results with those from block surveys within the same grid squares. Habitat-specific densities were multiplied by habitat availability in the study area to give habitat-specific totals, which were summed to estimate total population size. Clutch survival was monitored using camera traps. Population status was assessed from repeat surveys approximately 10 years apart. All but one surveyed square supported Eurasian Curlews, with densities highest in rough grazing and grass-moor habitats at mid-elevations. Twice as many Eurasian Curlews occurred on blanket bog managed by burning and cutting than on unmanaged bog. Abundance from whole-square searches (block surveys) was 29% higher than from transect surveys in the same squares. Summed habitat-specific totals gave 1,764 pairs. Estimated clutch survival of Eurasian Curlews was 0.51, averaging 0.71 for four wader species combined. The most frequent clutch predators detected were Eurasian Badgers Meles meles, Stoats Mustela erminea and Sheep Ovis aries. Eurasian Curlews fledged 1.0 chick per pair, double the number needed to sustain numbers. Repeat surveys indicated that breeding numbers were stable in recent years at both scales. High densities and high breeding success of Eurasian Curlews occurred within connected open-ground upland habitats within designated protected landscapes, where licensed culling of predators and management of blanket bog by gamekeepers to produce Red Grouse Lagopus scotica for recreational shooting, together with wildlife-friendly farming, were widely practised.

The present study aimed to evaluate the ecological niche characteristics, habitat preferences and potential lineage differentiation of Anatololacerta ibrahimi occurring west of the Göksu River and Anatololacerta danfordi distributed east of the river. By integrating ecological niche modelling, niche overlap analyses and habitat connectivity assessments, ecological niche models based on bioclimatic variables yielded high predictive performance, with area under the curve (AUC) values of 0.960 (TSS = 0.952) for A. ibrahimi and 0.986 (TSS = 0.979) for A. danfordi. Similarly, models incorporating topographic predictors showed very high accuracy, with AUC values of 0.992 (TSS = 0.985) and 0.977 (TSS = 0.976), respectively. Niche overlap analyses revealed limited overlap in environmental space, suggesting structured environmental segregation between taxa. Connectivity analyses further indicated that potential ecological corridors between the distributions of A. ibrahimi and A. danfordi exhibit low passage quality and potentially limit dispersal between suitable habitat patches across the Göksu River region. Ecological differentiation between the two lineages was primarily associated with seasonal vegetation dynamics, with A. ibrahimi linked to winter–spring productivity (January, February, June NDVI), whereas A. danfordi showed stronger associations with peak summer productivity (July NDVI). Collectively, these results provide ecological evidence consistent with niche differentiation playing a role in the divergence of these taxa.

The Saudi Arabian Red Sea coast supports coastal communities that depend heavily on fisheries as a major source of protein, making it important to clarify the genetic connectivity of key exploited species for effective management. In this study, an initial evaluation of the population structure of Scomberomorus commerson – a species of ecological and economic significance – was conducted using mitochondrial DNA markers, including cytochrome b (cyt b) and cytochrome oxidase I (COI). Pectoral fin tissues were obtained from fish sold in markets distributed across the central and southern portions of the Saudi Red Sea coast. A 571-bp fragment of the mtDNA cyt b locus was sequenced from 90 individuals, yielding 12 haplotypes and 10 variable positions, with average haplotype and nucleotide diversities of 0.4677 and 0.0008, respectively. The 635-bp COI segment recovered six haplotypes and six segregating sites, with a corresponding mean haplotype diversity of 0.758 and a nucleotide diversity of 0.0024. These results are consistent with high genetic connectivity among sampled locations along the central and southern Saudi Red Sea coast. Phylogenetic analyses further indicated that the Saudi Red Sea samples formed a cohesive genetic group relative to reference sequences from outside the region. The results from mismatch distribution and neutrality tests were consistent with recent demographic expansion. Overall, the study underscores the importance of coordinated regional management, including mtDNA-based genetic monitoring and broader ecological assessment, to support the long-term sustainability of S. commerson in the Red Sea.

In the present study, the families Embolemidae and Sclerogibbidae are recorded for the first time in the fauna of Saudi Arabia. They are represented by six species: Embolemus harteni Olmi (Embolemidae), Sclerogibba berlandi Benoit, S. magrettii (Kieffer), S. rossi Olmi, S. talpiformis Benoit, and S. vagabunda (Bridwell) (Sclerogibbidae). Furthermore, two species are newly recorded from Egypt (S. rossi), and Jordan (S. magrettii). Illustrated diagnoses are provided for each of the species studied, along with a faunistic list. An identification key to the Saudi Arabian Embolemus and Sclerogibba species is also provided, along with distribution maps of the species of both genera in the Arabian Peninsula.

The landscape mosaic and increased heterogeneity resulting from a severe forest disturbance (windstorm followed by bark beetle outbreak) in Northern Italy increased suitable habitat for the European Nightjar, primarily due to the newly established shrub cover. In 2024, we investigated the occupancy pattern of the European Nightjar in a forest area in Trentino (Italy) damaged by the Vaia windstorm in 2018 and by a subsequent bark beetle infestation (mainly the Eight-toothed Spruce Bark Beetle Ips typographus). We conducted point count surveys at 52 points across the 200 ha study area, encompassing a range of different types of environments, including intact forest, pre-existing clearings and windthrows caused by the Vaia storm. We found a positive effect of shrub coverage on European Nightjar occupancy probability, while other storm-related features, e.g. roots and bare ground, had a positive (yet weak) influence. European Nightjars seemed to benefit from the mosaic of landscape features and increased environmental heterogeneity that have emerged in this post-windstorm forest area, which was previously dominated by closed-canopy conifer trees. Future management of the study area and similar sites should consider the ecological opportunities arising from disturbance, and the importance of preserving part of the new clearings with dead wood legacies, in order to build a more resilient and biodiverse forest ecosystem.

Human activity on a river significantly influenced the behaviour of urban Eurasian Coots outside the breeding season, as the birds spent more time swimming in response to boat traffic. Urbanization is associated with a range of environmental changes that influence animal behaviour. Urban animals respond to anthropogenic disturbances in various ways; however, their first visible response is typically behavioural, resembling antipredator reactions such as fleeing. I assessed the effects of human activities and environmental variables on multiple behavioural traits in Eurasian Coots wintering in the centre of a densely populated city (Belgrade, Serbia). Using multivariate models, I examined the effects of anthropogenic disturbance, air temperature, wind speed, time of day and flock size on several categories of Eurasian Coot behaviour simultaneously. Focal birds devoted different proportions of time to different activities, depending on anthropogenic disturbance, air temperature, wind speed, time of day and flock size. Exposure to boat traffic increased the time that Eurasian Coots spent swimming. Feeding activity declined around midday and was negatively associated with wind speed; self-maintenance behaviour increased with rising air temperature, while swimming activity decreased with flock size. This study provides evidence that anthropogenic disturbance negatively affected the behaviour of urban Eurasian Coots, which spent more time swimming at the expense of fitness-enhancing activities, such as feeding and preening.

This first detailed investigation into the diet of Little Terns along the North Atlantic coast of Morocco, focusing on the tidal zone of Mansouria over six years, highlights the species’ dietary composition during chick-feeding at an important nesting site. To assess the diet composition and foraging behaviour of Little Terns in the tidal habitat near its breeding site on the Mansouria coast, in Morocco, with a focus on prey diversity and changes the prey species delivered to chicks over time. Fieldwork was conducted over six breeding seasons (2009–2014) in a 38-ha estuarine area (2 km long, 0.3 km wide) near the Moroccan cities of Mohammedia and Bouznika. Data collection included direct visual observations, photographic documentation of foraging behaviour and analysis of prey remains found near nests. From a total of 105 prey items identified, Little Tern chick diet predominantly consisted of fish (n = 93, 88.6%) and arthropods (n = 12, 11.4%). Key fish species identified were European Pilchards (Sardina pilchardus; n = 33, 31.4%), gobies (mainly Gobius niger; n = 20, 19.0%), White Seabreams (Diplodus sargus; n = 16, 15.5%) and sand smelts (Atherina spp; n = 13, 12.4%). Chicks were initially fed small fish, with prey size increasing as the chicks grew. This study provides an initial assessment of Little Tern chick diet in Moroccan coastal waters. While limited to low-tide observations, the findings emphasize the significance of the Mansouria tidal zone as a critical feeding habitat, supporting calls for its conservation.

Non-native ant species constitute an important component of global biological invasions. Globally, approximately 520 ant species are known to have spread beyond their native ranges, of which more than 300 are established. In Türkiye, 17 non-native ant species have previously been reported. Here, we reassess the status of non-native ants based on material collected between 2016 and 2025 by the authors and citizen scientists, together with a critical evaluation of published records. We report Pheidole parva and Crematogaster scutellaris as newly recorded non-native species for Türkiye, and provide the first locality data for Tetramorium bicarinatum and Hypoponera punctatissima. Conversely, seven species previously listed for the Turkish ant fauna – Linepithema humile, Camponotus compressus, C. maculatus, C. variegatus, Nylanderia vividula, Pheidole megacephala, and Strumigenys membranifera Emery – are excluded due to the lack of recent, verifiable records. In addition, Monomorium subopacum and Hypoponera eduardi are here regarded as native to the Turkish ant fauna. As a result, the number of confirmed non-native ant species in Türkiye is updated to 10.

Knowledge of the distribution and reproductive habitats of the Lusitanian cownose ray (Rhinoptera marginata) in the northeastern Mediterranean remains limited, and potential nursery areas for the species have not yet been clearly identified. This study reports new records of pregnant females and newborn individuals and reviews available occurrence data to evaluate whether İskenderun and Mersin Bays may function as potential nursery habitats. Opportunistic records obtained from fisheries and observational sources were compiled together with newly documented captures from the northeastern Mediterranean coast of Türkiye, and spatial and seasonal patterns were examined. The combined dataset provides additional insight into the seasonal occurrence of pregnant females and near-term embryos in the region. Recurrent records from İskenderun and Mersin Bays suggest that these coastal areas may represent a potential nursery habitat. Environmental conditions, including muddy shelf sediments enriched by riverine inputs, may provide suitable feeding grounds for both adults and juveniles. However, demersal fishing grounds overlap with these areas, potentially exposing vulnerable life stages to fishing pressure. Although the available data are largely opportunistic, the findings highlight the ecological importance of the region and the need to conserve breeding populations in the northeastern Mediterranean.

Over time, the total number of bird species and individuals recorded on bird surveys decreased for older observers, whereas they increased for young observers. We hypothesized that observer age and sex influence long-term bird survey results, with older observers recording progressively fewer birds, and with women performing better than men. We also assumed that the habitat in which the surveys are conducted plays a role in these effects. We used data from 99 sites and a 20-year period of the Austrian Common Bird Monitoring Scheme. We calculated the total number of species and individuals recorded at each site and year. We fitted linear models for each individual site and for both variables, with count year as an independent variable. We then used the resulting slope values in linear mixed-effects models, with observer age, observer sex, habitat and start year as explanatory variables. Finally, we excluded birds with high-pitched songs from the dataset and re-ran the models. Observer age significantly influenced the linear regressions’ slopes of the total number of species and individuals. Young observers produced slight increases, while older observers produced slight decreases. Female observers tended to show increases up to a greater age than males, but this result was not significant, probably due to the small sample size for females. Habitat had no significant influence. When excluding birds with high-pitched songs, the effect sizes approximately halved for both dependent variables. We found proof of observer effects in the analysed data. In relation to age, we concluded that there is an optimum curve, with middle-aged observers causing neither positive nor negative bias in long-term counts. We discuss how learning effects, hearing impairment, other ageing effects or sex-related differences could influence our results. Lastly, we address several options for dealing with observer effects.

The genus Villa Lioy, 1864 (Bombyliidae: Villini) is a species-rich genus in the Palaearctic Region and is represented in Iran by eighteen species. A new species, Villa gymnancylax sp. nov., is described from central Iran. Diagnostic morphological characters, including male and female genitalia, are illustrated. The new species was reared from a pyralid moth host. The pupal exuviae of the new species are also described and illustrated. http://www.zoobank.org/urn:lsid:zoobank.org:pub:524D5193-EDC1-47C0-B19B-F22610711A68

Apostenus turcicus sp. n. is described based on male and female specimens collected from the eastern Mediterranean region of Türkiye. The number of known Apostenus species in Türkiye has now risen to two, with A. fuscus being the other species. The new species can be easily distinguished from other known congeners by its male palp with a tegular apophysis and its epigyne with a posteriorly located spermatheca. http://www.zoobank.org/urn:lsid:zoobank.org:pub: 9330070C-B153-4C70-818B-E5BB29D12B4B.

As a result of the identification of Charophyceae members collected during field studies on Gediz Basin management and sustainability, the genus Tolypella was observed for the first time in Türkiye. Samples collected from the temporary inland saline and brackish waters section of the periodic wetlands located within the Gediz Delta are among the primary macrophytes of their system. The general morphological description of the species T. salina, the determination of the EUNIS habitat class, vegetation types and ecology, the classification of the temporary waterland where the species lives, and its distribution worldwide are included in our detailed research. Furthermore, factors threatening the habitat and existence of the T. salina species have been detailed due to its 'EN' category status on the IUCN Red List. Although the Ramsar protection status of the region where the species was identified and the intensive conservation activities of private civil society organizations in the area are promising, the shift in rainfall patterns due to the global climate crisis is negatively affecting the species' diaspora formation. Therefore, it is of great importance to reveal the life history of T. salina, measure the population size and the species' actual distribution area, and determine the population genetics. With the addition of the genus Tolypella, the current number of Charophyceae in Türkiye has reached 3 genera and 20 taxa.

De nouvelles données (répartition, biologie et genitalia) sont présentées pour quatre espèces de Lépidoptères observées en Camargue (France, Bouches-du-Rhône) : Xenopathia novaki (Rebel, 1891) [Blastobasidae], Monochroa moyses Uffen, 1991 [Gelechiidae, Anomologini], Synanthedon theryi Le Cerf, 1916 et Bembecia ichneumoniformis ([Denis & Schiffermüller], 1775) [Sesiidae].

Eristalinus megacephalus (Rossi, 1794) a été observée pour la première fois en Camargue (delta du Rhône, France) en 2015, où elle y est désormais très abondante. Cette note rassemble des observations et expérimentations sur l’écologie de l’espèce, en particulier de la ponte à l’imago. La ponte a été observée dans une prairie inondée, avec oviposition directement dans de la bouse de vache. La durée d’incubation observée est de trois jours et les imagos ont émergé entre 20 et 40 jours après la ponte. La durée de développement larvaire ne semble pas être influencée par la présence ou l’absence d’immersion du substrat.

Cet article décrit l’observation, réalisée le 8 juillet 2025 dans la réserve naturelle nationale de Camargue, d’une Couleuvre vipérine s’attaquant à une anguille européenne. La connaissance actuelle fait état d’un seul cas similaire de prédation, recensé en France jusqu’à présent. Trois cas similaires avaient été signalés en Espagne.

L’article relate la découverte de restes d’une Tortue mauresque (Testudo graeca) dans des pelotes de réjection d’un Grand-duc ascalaphe dans la région de Khangat Ksat (Sahara Atlantique marocain), à 160 km au sud de la limite connue de son aire de répartition. Cette observation, effectuée en mars 2026 lors d’une mission naturaliste, suggère l’existence d’une population marginale relicte de cette espèce, favorisée par un micro-écosystème local riche en biodiversité (gazelles, renards, reptiles, etc.) et des conditions écologiques favorables, malgré la désertification. Le site, isolé et peu fréquenté, exclut une introduction humaine. Les auteurs émettent l’hypothèse que cette zone agit comme un refuge écologique pour des espèces non sahariennes, comme le Caméléon commun ou le Fouette-queue du Maroc, observés à proximité. Cette découverte ouvre des perspectives pour des recherches approfondies sur la résistance de certaines espèces face aux changements climatiques. [résumé rédigé à l'aide d'une IAG]

L’article présente un inventaire préliminaire des micromammifères dans la région de Khangat Ksat (Province de Smara, Maroc), réalisé en mars 2026 lors d’une mission naturaliste. Sept espèces de rongeurs ont été identifiées, dont certaines comme la Gerbille naine d’Égypte, la Gerbille pygmée, le Rat de sable diurne et le Mérione à queue rouge, dont la présence étend ou comble des lacunes dans leurs aires de répartition connues. Les méthodes utilisées incluent des pièges Sherman, des observations directes et l’analyse de pelotes de réjection d’un Grand-duc ascalaphe. Cette étude révèle que Khangat Ksat constitue une nouvelle station écologique pour ces espèces, confirmant son rôle comme zone de biodiversité dans le Sahara Atlantique marocain.

Cet article décrit la colonie de hérons arboricoles installée depuis 2004 dans un bois de tamaris inondé au nord-est de la Réserve naturelle régionale du Scamandre, en Petite Camargue gardoise. Après 950 couples dès sa première année, elle a atteint un pic exceptionnel en 2005 avec plus de 3 800 couples de six espèces (majoritairement des Hérons garde-bœufs et des Aigrettes garzettes), ce qui en fait la plus grande colonie de hérons arboricoles jamais dénombrée en France, représentant alors environ 40 à 50 % des effectifs camarguais de plusieurs espèces. En 2006, la colonie s'est maintenue avec environ 3 100 couples, marquée par la nidification réussie de 14 couples d'Ibis falcinelles, une première après dix ans sans reproduction de cette espèce. Les auteurs notent que sa croissance très rapide a probablement drainé les effectifs d'autres colonies environnantes, mais que son avenir reste incertain, car en Camargue aucune colonie dépassant 1 000 couples n'a duré plus de six ans.[résumé rédigé à l'aide d'une IAG]

Sur le littoral picard (Pas-de-Calais et Somme), le Cygne chanteur demeure un hivernant exceptionnel tandis que le Cygne de Bewick est devenu régulier en très petit nombre lors de cette saison. Les deux espèces fréquentent deux grands types de biotopes : grands plans d’eau (surtout comme remise nocturne) et les milieux (notamment pour l’alimentation). Cette activité présente un rythme bimodal comme chez d’autres espèces aviennes qu’il s’agisse en particulier d’anatidés et de passereaux. Le Cygne chanteur consacre moins de temps à l’alimentation que le Cygne de Bewick probablement en raison d’une consommation d’aliments plus énergétiques. Chez cette dernière espèce, les jeunes consacrent davantage de temps à l’alimentation que les adultes.

La distance de fuite (Df), la distance jusqu'à laquelle un animal sauvage peut être approché avant qu'il ne s'enfuie, est un paramètre largement utilisé dans l'étude des relations prédateurs-proies. Je l'ai mesurée chez le Tarier pâtre, un petit passereau insectivore et migrateur, et ai déterminé quels facteurs pouvaient l'affecter lors d'une approche humaine. La Df moyenne du Tarier pâtre est de 31 m et ne diffère pas entre mâles et femelles. Elle diminue lors d'approches successives entrecoupées d'une courte pause, témoignant d'une habituation. Df est d'autant plus courte que l'oiseau est haut perché, diminuant de 2 m pour une élévation de 1 m de la hauteur de perchage. Plus l'oiseau approché est proche d'un refuge, plus Df est faible. La décision de s'enfuir dépend donc du niveau de sécurité que procurent à l'oiseau hauteur de perchage et proximité d'un refuge. Df est aussi d'autant plus courte que l'oiseau est attaché à son territoire, ce dont témoignent les cris d'alarme émis quand on approche à proximité de son nid ou de ses petits. Df varie aussi nettement entre les individus, certains d'entre eux, plus audacieux, retardant le moment de s'enfuir. La distance sur laquelle l'oiseau s'envole après avoir fui est elle aussi d'autant plus courte que simultanément un refuge est proche et le niveau des alarmes élevé. En accord avec les théories actuelles, mes résultats montrent que chez le Tarier pâtre la décision de s'enfuir lors de l'approche d'un prédateur est modulée par de nombreux facteurs et qu'elle prend en compte simultanément les risques liés à l'approche et les coûts liés à la fuite.

Pour maintenir un bon état sanitaire du nid, certaines espèces d’oiseaux en expulsent les œufs non éclos (Guigueno et al., 2009). D’un point de vue évolutif, ce comportement est considéré comme précurseur de l’expulsion des œufs « étrangers » pour limiter le parasitisme du nid (Li et al., 2021). Elle n’est pas rare chez l’Hirondelle rustique Hirundo rustica (Yang et al., 2014 ; Yang et al., 2022), peu fréquente chez l’Hirondelle de l’Amour Cecropis daurica (Yang et al., 2014), mais jamais notée chez son vicariant occidental, l’Hirondelle rousseline C. rufula (de Lope Rebollo, 1980). Au cours de plusieurs contrôles de la reproduction de l’Hirondelle rousseline en Corse sur la période 2023-2025, nous avons constaté dans un site des disparitions d’œufs exceptionnelles dont nous avons cherché la cause.

Cet article décrit finement l’histoire naturelle de la Perdrix grise de plaine en période de ponte à partir d’un suivi GPS localisant 16 femelles tous les quarts d’heure entre le lever et le coucher du soleil avec une précision de 5 mètres. Cette description concerne 9 nids qualifiés de « certains » car le stade de couvaison de la ponte a pu être atteint (8 femelles, 115 pontes d’œuf décrites), complétée des données de 9 autres nids qualifiés de « probables » car le stade de couvaison n’a pas été atteint (9 femelles, 111 pontes d’œuf). Le calcul de la distance de chaque localisation GPS des femelles à leur site de nid a permis de caractériser leur rythme d’activité durant la période de ponte : les horaires de ponte des œufs (91 % entre 10 heures et 18 heures, horaire soit variant selon le rang de l’œuf dans la séquence soit très régulier), le profil de ponte (longueur des séquences (1-3 œufs, parfois 4-5, rarement 10-15 ; durée et fréquence des pauses), le temps passé au nid pour pondre un œuf (moins de 2 heures, plus de 3 heures dans de rares cas), l’intervalle entre la ponte de deux œufs successifs (généralement 1 ou 2 jour(s), rarement 3 ou 4 jours). Ces estimations concordent avec les données de la littérature, obtenues en nature comme en captivité. Pour autant cette étude apporte des informations inédites sur cette espèce en nature : elle estime la durée de constitution de pontes, elle décrit les profils de ponte des œufs, elle apporte un complément finement chiffré quant à la variabilité intra- et inter-individuelle du rythme d’activité des perdrix et analyse les facteurs d’influence, et elle décrit les trajectoires des femelles relativement à la position de leur nid.