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Molt is critical for birds as it replaces damaged feathers and worn plumage, enhancing flight performance, thermoregulation, and communication. In passerines, molt generally occurs on the breeding grounds during the postbreeding period once a year. However, some species of migrant passerines that breed in the Nearctic and Western Palearctic regions have evolved different molting strategies that involve molting on the overwintering grounds. Some species forego molt on the breeding grounds and instead complete their prebasic molt on the overwintering grounds. Other species molt some or all feathers a second time (prealternate molt) during the overwintering period. Using phylogenetic analyses, we explored the potential drivers of the evolution of winter molts in Nearctic and Western Palearctic breeding passerines. Our results indicate an association between longer photoperiods and the presence of prebasic and prealternate molts on the overwintering grounds for both Nearctic and Western Palearctic species. We also found a relationship between prealternate molt and generalist and water habitats for Western Palearctic species. Finally, the complete prealternate molt in Western Palearctic passerines was linked to longer days on the overwintering grounds and longer migration distance. Longer days may favor the evolution of winter prebasic molt by increasing the time window when birds can absorb essential nutrients for molt. Alternatively, for birds undertaking a prealternate molt at the end of the overwintering period, longer days may increase exposure to feather‐degrading ultra‐violet radiation, necessitating the replacement of feathers. Our study underlines the importance of the overwintering grounds in the critical process of molt for many passerines that breed in the Nearctic and Western Palearctic regions., Our study explored the potential drivers of the evolution of winter molts in Nearctic and Western Palearctic breeding passerines. Using phylogenic analysis, we tested whether photoperiod, migration distance, NDVI of the breeding and overwintering grounds, habitat, and diet were associated with species undergoing a winter prebasic molt or a prealternate molt. Our study suggests that the evolution of winter molt strategies in Nearctic and Western Palearctic migratory passerines was likely driven by multiple factors, but photoperiod, migration distance, and overwintering ground conditions are particularly important.

International audience; After spectacular population crashes in the 1960-70s, Peregrine Falcons Falco peregrinus recovered worldwide, and in the 2000s many study populations were back to normal. However, post-recovery trends have not been documented. We combined three long-term population studies covering the entire Jura mountains (16,304 km²) to examine spatio-temporal variation in population dynamics during 2000–2020 in 420 known nesting sites in five regions: Ain, Jura and Doubs in France, and Jura Sud and Jura Nord in Switzerland. Every year about 60% of all sites were surveyed at least once, and this proportion increased over time. We used Bayesian occupancy modeling to investigate site persistence and colonization probabilities and correct status and trend estimates for bias due to nonrandom site coverage. Based on the average of two models correcting for preferential sampling, we estimated that population size peaked in 2002 (Jura), 2005 (Doubs), 2007 (Ain, Jura Nord) and in 2007 for the Jura as a whole. Thereafter, the population declined significantly in four regions and in the Jura as a whole, with the strongest decline found in the Jura Nord ( –38%, CRI –34%/–41%) during 2007–2020. Thus, we found considerable spatial heterogeneity in post-recovery trends and widespread post-recovery declines. Reasons for the latter may include eagle owl predation, illegal persecution, and human disturbance. Our results illustrate how quickly positive population trends may be reversed, such that continuous long-term monitoring even for species seemingly "out of danger" remains invaluable. Our study also emphasizes the importance of correcting for both coverage bias in general and for preferential sampling in particular when assessing population trends in studies where not every territory can be surveyed in all years.

The analysis of feeding strategies in animals is one of the most important topics in foraging ecology. The individual’s foraging behavior depends on both the individual’s own actions and the behavior of other foragers. Here we analyse the effect of the sex and group size on the foraging behavior of immature Olrog’s Gull (Larus atlanticus Olrog, 1958), endemic to the Atlantic coast of southern South America and regionally listed a threatened species. Birds were captured, banded, sexed, and aged during the non-breeding season in Mar Chiquita coastal lagoon, Argentina. The foraging behavior was quantified by observations made on individuals of known identity, recording the size of foraging groups, as well as prey size and type. Foraging parameters estimated were foraging effort, capture rate, and foraging efficiency. Males spent more time in agonistic behavior and captured larger prey. With an increase in group size, the capture rate, the capture of small crabs by males, and the foraging effort were higher. The agonistic behaviors, size of consumed prey, and foraging effort were affected by individual identity. Our study pinpoints factors underlying variation in the foraging behavior of Olrog’s Gulls and illustrates the importance of modelling individual variation when analyzing foraging behavior.

The Brambling Fringilla montifringilla combines several special features of migration and wintering: differential migration according to age and sex groups, large differences in winter densities as a response to food availability, and flocking behaviour as a response to local mass fructification of the beech Fagus sp. resulting in roosts of several million birds. This study examines (a) whether Bramblings participating in mass concentrations originate from different, or additional, breeding grounds compared with birds present in normal winters, and (b) how differential migration according to age and sex groups combines with irruptive migration and with congregations in mass roosts, i.e., whether the benefits from mass concentrations differ between age and sex groups. Wing biometry (wing length, lengths of outer primaries, and wing pointedness) did not vary geographically, as shown by museum skins, and was therefore not helpful to reveal differences in origin between birds of mass concentrations and normal winters. The extent of the post-juvenile moult was smaller in mass concentration birds and suggests that slightly later-born juveniles, i.e., born further east or north, participate in mass concentrations. Ringing recoveries could not demonstrate a difference in breeding range origin of Bramblings which participate in mass concentrations versus Bramblings in normal winters in Switzerland. However, this may be due to insufficient recoveries of ringed birds. A rough estimate suggests that the number of Bramblings migrating SW on a broad front across Europe could be sufficient to form mass concentrations of up to 10 million birds which are halted by a large area of beech mast. Across Europe, the proportion of juvenile males decreased towards south (i.e., with increasing migration distance) in autumn migrants and wintering birds, while adult females showed the opposite pattern, and adult males and juvenile females were intermediate. Mass concentrations in Switzerland were composed of significantly more adults, especially adult males, and fewer juveniles, particularly juvenile females, while the sex–age composition outside mass concentrations was similar to normal winters. Adults and females likely benefit from wintering further south where snow is less likely to cover food of this ground-feeding finch. On the other hand, the costs of migration are probably substantial in terms of direct costs or indirectly in terms of reaching the breeding grounds, so that juvenile males prefer to winter closer to the breeding area than adults. Feeding in large flocks in beech mast areas incurs the high risk of being cut off from this food by snowfall. Adult males are apparently best adapted to this risk, and hence predominate in mass concentrations.

Incubation behaviour is essential for understanding the reproductive success in birds. For example, the orientation of the bird is important for reducing incubation costs associated with wind or sun, but on the other hand can be modified by the perceived risk of predation. We studied the body position of incubating White Stork Ciconia ciconia in eastern Poland using a small unmanned aerial vehicle (drone). The head and body orientation of the incubating storks was non-random and modified by natural factors, mainly wind direction and speed, but also by the presence of an apex predator, the White-tailed Eagle Haliaeetus albicilla. However, head orientation during incubation in nests located on electricity poles was also modified by the presence of the power lines, probably due to disturbance in the magnetic field detected by birds. Surprisingly, although the positioning of incubating birds (mainly females) is very important for the detection of predators and for reducing energy costs, these have not previously been studied. New technologies, such as drones, make it possible to collect new, extensive information on the incubation behaviour of birds.

SummaryTree characteristics, microhabitat, and human presence were measured around nest trees (n= 92) and non-nest trees (n= 92) to identify the best predictors of the European Turtle-doveStreptopelia turturnest occurrence in date palm plantations of the Biskra region (Algeria). Nest occurrence was (i) positively influenced by the height of trees and that of the herbaceous layer, and (ii) quadratically affected by diameter at breast height (DBH), the cover of trees, the cover of the herbaceous vegetation, and the distance to the edge of date palm plantation. Variation partitioning analysis revealed that the pure effect of tree physical characteristics (tree height and DBH) was robust in explaining the occurrence of Turtle Dove nests (adj.R2= 0.52,P= 0.001). For an efficient management of this Saharan population, special attention should be paid in the short term to keeping high date palm trees while ensuring, in the medium and long term, the presence of different-sized palm tree classes at each exploitation. There is no doubt that date palm plantations of Biskra are of paramount importance because they offer good opportunities for consolidating and improving the knowledge on this threatened species and other species at the Sahara edge.

SummaryThe Great Bustard Otis tarda is a globally threatened species with populations inhabiting the steppe zones of Turkey. In recent decades, its populations in Turkey have suffered severe declines in range and size. Although the remaining populations are in urgent need of protection, there has been no national-scale study on the species since 2009, and huge information gaps remain concerning its range, abundance, and movements in the country. Here, we combined data from five years of fieldwork together with all available sight and literature records to present up-to-date estimates of distribution and population size in Turkey, to better understand its movement patterns, to reveal its recent and historical population changes, and to assess its national extinction risk and threats. We find that the species’ breeding population has shrunk by 20–29% over the last five years, and there are only 559–780 breeding Great Bustards in Turkey distributed in two discrete subpopulations. Comparison with historical records shows that the species’ range has shrunk by at least 60% since the beginning of the 20th century. We suggest possible migratory routes within and through Turkey and that Turkey might have a higher regional importance for the species than previously thought. Illegal hunting, agricultural intensification, shift to irrigated crops, overgrazing, collision with powerlines, and disturbance are the most severe threats to the species in Turkey. Our national Red List assessment yields an Endangered categorisation. Further studies are needed to understand the metapopulation structure and movements of the species and to conserve its remaining populations in Turkey.

The growth of a nestling during the first few weeks after hatching is crucial for its further life and is sensitive to the conditions experienced during this period. Among species exhibiting Sexual Size Dimorphism (SSD), one of the most important factors influencing growth parameters is the sex of the hatchlings. In this study, we tested whether sex and other factors (hatching date, egg volume, brood size and sex ratio in the brood) were related to sex on growth parameters in Whiskered Tern (Chlidonias hybrida) chicks. In this species, males are 3%–10% larger than females when adult. At hatching, only the total head length was greater in males than females, but values close to fledging were greater for most of the measured parameters (3%—tarsus, 4%—total head length, 13%—body mass). Moreover, the maximum body mass growth rate was higher in males but females entered the rapid growth phase somewhat earlier and achieved the final total head length sooner. Nestling growth was also significantly correlated with brood size and hatching date, though mostly negatively (e.g. lower tarsus and total head length asymptote, lower maximum growth rate and growth rate constant of total head length in bigger and later clutches). The occurrence of SSD during the nestling period and higher maximum growth rate of body mass in males indicates that the costs of raising sons may be higher than of raising daughters. However, we did not find evidence of either sex-biased nestling mortality or skewed sex ratio.

Introduction. Ethiopia is one of the most avifauna rich countries in Africa. Avifaunal surveys are required to inform conservation decisions and enhance land management for biodiversity. Avifaunal surveys from Ethiopia are lacking. This study examines species composition, relative abundance, and habitat association of avian fauna in Zegie Peninsula forest patches and associated wetlands from surveys carried out from August 2018 to March 2019, covering both the wet and dry seasons. Data Collection. Forest, shrub, lakeshore, and wetland habitats were identified as ecologically relevant habitats in the study area for data collection. Data were collected using point count and line transect methods, for 24 days in total for both seasons in the morning and afternoon. Results. A total of 96 species of birds were identified during the whole study period. Out of the total, 40 species were observed during the wet season, 13 during dry and 43 species in both seasons. There was significant variation of species distribution among habitats. During the wet season, the highest species diversity was recorded in the wetland habitat followed by forest habitat. During the dry season, avian diversity was the highest in the lakeshore followed by wetlands. The highest evenness was observed in the shrubland during both the wet and dry seasons. During the wet season, the highest species similarity was recorded between wetland and lakeshore habitats, and during the dry season, the highest species similarity was recorded between forest and shrub habitats. Based on encounter rate data, 64 (66.66%) of the avian species were uncommon. Conclusions. Compared to previous studies conducted in the study area, species diversity was lower. This might be due to various anthropogenic activities such as deforestation of trees for timber and cutting trees for firewood. Therefore, awareness creation should be given to the local community to reduce habitat destruction due to various human-induced factors.

The California Endangered Species Act (CESA) is one of the most important legal tools available to the Fish and Game Commission and Department of Fish and Wildlife to protect the State’s wildlife resources. The listing process, together with the prohibitions in section 2080 of the Fish and Game Code, are the law’s regulatory teeth. At the same time, because any interested person can petition to list a species, the listing process invites citizen participation in the regulatory scheme. Listing decisions can be the difference between persistence and extinction of a species. They can also cause severe economic disruption and, for this reason, should in our view be made with due deliberation and based on the best available scientific information. Here we describe the complex roadmap that petitions must navigate and that is intended to assure that only native species that need protection get it.

SummaryAlong with many long-distance migrant passerine species in the East Asian-Australasian Flyway, the migratory Brown Shrike Lanius cristatus superciliosus has been sharply declining throughout its breeding range. Its breeding range in Japan shrank by 90.9% between the 1910s and 2010s. In contrast, the closely related but resident Bull-headed Shrike L. bucephalus bucephalus has been gradually declining but is still a common resident in Japan. To better understand the drastic decline of Brown Shrike, we compared the pairing success during three consecutive breeding seasons of these two species. About 60–70% of Brown Shrike males were unpaired, which was much higher than the percentage of unpaired male Bull-headed Shrike (c.0–20%). Brown Shrike males arriving later did not pair because the population’s sex proportion is heavily biased toward males. One of the factors of male-biased population of Brown Shrike may be female-biased mortality in wintering sites, or on the migratory journey, and tracking studies will be required to test this.

The Egyptian Vulture (Neophron percnopterus) is an endangered species with a globally declining population. Information on the current habitat distribution and potential suitable habitat for this ecologically important species will provide invaluable insight into conservation planning and the species’ future status as climate changes. This is specifically important for areas where there are little or no reported data on the status of the Egyptian Vulture. We used 13 years nest-site records (n = 69) together with relevant environmental variables to understand the known distribution and predict potential habitat distribution of the Egyptian Vulture in the Kurdistan Region of Iraq. A machine learning model, maximum entropy, was used to generate various model options, from which the best model was selected based on the Akaike information criterion (AICc) statistical indicators. The model showed reasonably good discriminative ability using both True Skill Statistics TSS = 0.722 and Area under the Curve (AUC) = 0.825 metrics. The Egyptian Vultures in Iraq mainly breed in territories at elevations between 1000 and 3300 m above sea level. This suggests that the species shows preference to areas distant from human settlements likely due to decreased disturbance and that the species may rely on alternative/complementary food sources (e.g. wild goat and boar). The total area of the study site is approximately 51,069 km2, out of which around 25% (12,767 km2) is predicted as suitable breeding habitat for the Egyptian Vulture. The output of this study provides useful baseline information for conservation actions and plans.

High diversity, complex topography and geological factors make the Neotropics an interesting region for the study of avian diversification. Phylogeography, in conjunction with ecological niche modeling, offers an interesting complementary approach to identify the tempo and mode of diversification in different species. In this work, we analyzed the genetic structure of Habia fuscicauda based on multilocus analyses using mtDNA (ND2 and ND4) and nuDNA (ACOI-I9 and ODC) sequences. Additionally, we transferred the optimal conditions for current distribution to the Mid-Holocene, Last Glacial Maximum and the Last Inter-Glacial in order to evaluate the shift in species distribution and compare with the genetic data. Our results indicate that H. fuscicauda comprises two clades: one with genetic correspondence to south-east Mexico to the Nicaragua Depression and the other from the south of the Nicaragua Depression to Central Panama. Within these clades, we identified genetic differentiation between populations across the Isthmus of Tehuantepec, Costa Rica—associated with the Talamanca Cordillera—and Central Panama. The two principal clades showed contrasting demographic histories, with the northern clade showing demographic changes and the southern clade demographic stasis. The ecological niche models identified areas as refugia for the northern clade fin Central America and for the southern clade in the Talamanca Cordillera and Central Panama, supporting the hypothesis that these clades were isolated from each other during the climate shifts of the Pleistocene.

The harriers (Accipitridae: Circus) represent a unique group of raptorial birds due to their hunting behaviour and their facial ruff and prominent facial disc. During previous studies it was suggested that harrier species may have other convergent features shared with owls like asymmetric or enlarged ear openings related to sensitive hearing capabilities. In this study, cranial asymmetry was done using SAGE (Symmetry and Asymmetry of Geometric Data) software. 32 skulls of 3 species (Western Marsh Harrier (Circus aeruginosus) n=8, Montagu’s Harrier (Circus pygargus) n=10, Hen Harrier (Circus cyaneus) n=14) were photographed, digitized and assigned with 2D landmarks with TpsDig software. The variables were analysed based on Generalized Procrustes analysis. The morphometric data showed cranial asymmetry of harriers. This asymmetry should rather be explained by foraging strategies as the results are corresponding to the exceptionally good hearing of these species among diurnal raptors.

The authors compared the first phalanx of the second wing-finger of 93 species belong to 9 order (Gaviiformes – 2 species, Podicipediformes – 4 species, Pelecaniformes – 4 species, Ardeiformes – 12 species, Anseriformes – 27 species, Gruiformes – 4 species, Ralliformes – 6 species, Charadriiformes – 25 species and Galliformes – 9 species). The importance of studying this bone lies in the fact that, although it has diagnosable characteristics, it was practically neglected by osteologists and paleontologists. Thus, fossil materials can be identified through them, as well as those from owl pellets. The comparison was made possible by the comparative avian skeleton collection of the Hungarian Natural History Museum. The text is supplemented by 10 figures and 1 table.

The diet of the Red-footed Falcon (Falco vespertinus) was studied at Akrotiri Peninsula, Cyprus, in October 2008, during the autumn migration. Based on 180 pellets collected that represented 3,066 prey items, the diet consisted exclusively of invertebrates, nearly all preys were insects. Winged ants (Hymenoptera, Formicidae) formed 94% of the diet by number of specimens and 76% of biomass. Beetles (Coleoptera), mainly Carabidae and Scarabaeidae, made up 5% of the prey numbers but 22.5% of biomass. The other preys were made up by small numbers of earwigs (Dermaptera), true bugs (Hemiptera) and snails (Gastropoda).

We documented the foraging activities of woodpeckers on selected trees in an established conservation-oriented management study in five oak-dominated forests in Hungary. We examined the tree species preference of woodpeckers as a group and the impact of specific tree characteristics on the habitat use of woodpeckers. We estimated the percentage of visible foraging signs on the trunks and upper limbs of selected trees through the winter and early spring of 2019–2020. Based on the Jacobs’ index, woodpeckers preferred oak species for foraging and most foraging signs were on limbs rather than trunks. Foraging signs on trunks were more frequent on those of larger diameters and greater heights. It was also found that the lower the tree, the greater the effect of its diameter on the occurrence of signs.

Background In this study we examined the habitat preferences of three diurnal raptors in relation to human access. We aimed to identify the selection of breeding habitat by the Golden Eagle (Aquila chrysaetos), the Long-legged Buzzard (Buteo rufinus), and the Peregrine Falcon (Falco peregrinus) in response to site accessibility by humans, and in turn, the response of these species to human presence. Methods Data about the nest locations were collected. Analyses and maps were created using ArcGIS. The “least cost path” was defined using the Cost Path tool. Results The lowest values of the Cost Path were established for Long-legged Buzzard and the highest values were estimated for Golden Eagle. Intermediate Cost Path values for Peregrine Falcon were found. Conclusions The Long-legged Buzzard could be considered as the most tolerant to human presence in its breeding territories. The Golden Eagle have the lowest degree of tolerance and the Peregrine Falcon is ranked in an intermediate position compared to the other two species, but closer to Golden Eagle.

Based on 356 observations of Woodcock nestings published in the Hungarian hunting and ornithological literature between 1846 and 2019, which also includes published and unpublished personal observations, it can be stated that the nesting dates of Woodcock in Hungary are scattered over a large interval. 47.3% of all nestings registered with exact dates (n=93) happen in April. The second peak of breeding in June does not stand out significantly. Based on the data of the clutches (n=65) reported with known number of eggs, as well as the clutches (n=14) – probably with full number of eggs – found in the Hungarian egg collections, the average number of eggs per clutch was 3.8. Based on the observational data of the Woodcock families (n=36) observed during the study period, the number of chicks per hen was 3.6, of which the hens were able to raise an average of 2.8 chicks up to a flying age.

In a study of acoustic communication at seven nest cavities of Eurasian Wrynecks, sound recordings were made of ninety-one separate bursts of tapping. From Hungary in the east, and France in the west, tapping was heard both from inside cavities and at their entrances. Analysis of the tapping rhythms indicated two forms corresponding to different observed behaviour. They were never loud and were used exclusively in communication between breeding pairs. No functional significance was found in the only two brief examples of tapping fast enough to be described structurally as drumming.

Simulated social facilitation techniques (e.g. decoys and call playbacks) are commonly used to attract seabirds to restored and artificially created nesting habitats. However, a lack of social stimuli and conspecific cueing at these habitats may limit the use of these sites, at least in the short term. Therefore, testing the effectiveness of simulated audio-visual cues for attracting gregarious birds is important for conservation planning. In this study, we (1) assessed whether call playback and decoys were associated with an increased likelihood of Australian fairy terns Sternula nereis nereis visiting potentially suitable nesting habitats; (2) tested their behavioral response to different cues; and (3) documented whether social facilitation had the potential to encourage colony establishment. A full cross-over study design consisting of all possible pairings of decoy and call playback treatments (control [no attractants], decoys, call playback, both decoys and playback), allocated as part of a random block design, was undertaken at 2 sites. Linear modeling suggested that call playback was important in explaining the time spent aerial prospecting as well as the maximum number of fairy terns aerial prospecting, although this only appeared to be the case for 1 of the 2 sites. Decoys, on the other hand, did not appear to have any effect on time spent aerial prospecting. The results from this study suggest that audio cues have the potential to encourage site selection by increasing social stimuli, but attractants may be required over several breeding seasons before colonies are established.

During fieldworks in 2019, a pair of Red-rumped Swallows (Cecropis daurica) were seen building their nest (June) and one of them brooding (August). The pair was still present in the area by the end of September, while all other swallows left this breeding area. In June 2020, the nest entrance was destroyed and the nest was occupied by a pair of Passer sp. Another nest of C. daurica was found in an abandoned building but was completely destroyed. This observation is the first record concerning an attempt and failure of nesting of the species in Tunisia. The nesting area of the Red-rumped Swallow is extended to the Mediterranean in southern Europe and to northwest Africa. The nesting sites are described, and the extension of the nesting area is discussed in this work.

Inference studies from body mass during the non-breeding season are rare in seabirds due to methodological difficulties to sample individuals. Here, we used 12 years of data collected from 2000 to 2019 on about 6800 birds mist-netted at La Somone, Senegal along the East Atlantic Flyway to examine the role of intrinsic and environmental factors in explaining body mass variation in both Common Sterna hirundo and Roseate S. dougallii Terns. Most captured terns were subadults and adults aged three years and older, although ca. 22% of trapped Common Terns were immatures aged one–two years. Mean body mass values of Common and Roseate Terns were substantially lower than published values reported from European breeding sites. In both species, females were, on average, lighter than males, and in the Common Tern, immatures were also lighter than older individuals. Based on the subset of recoveries of birds initially marked at birth in Europe, we found significant differences in body mass according to natal origin in Common Terns but not in Roseate Terns. The variations reported for the former species were mainly attributed to size, with lighter and smaller individuals originating from the British Isles, intermediate individuals from western/central Europe, and heavier and larger birds from Fennoscandian countries. Capture date, used as a proxy measure of timing of migration, showed a strong covariation with body mass in both species. In fact, as the spring season progressed, mist-netted birds became progressively heavier, irrespective of age and natal origin. This suggests that earlier and lighter migrants may have opted for a more protracted migration duration involving more frequent and/or longer refueling periods. Conversely, late migrants needed greater body reserves to achieve the return journey to the colonies within a shorter period to arrive on time for the breeding season. Global climate phenomena such as the North Atlantic and Southern Oscillation indices did not explain inter-annual variations in body mass during the course of this study. Overall, our results suggest that, during the non-breeding season, body mass in these two long-distance migratory species is mainly shaped by intrinsic factors and inter-individual variation in migration strategy.

We thank the A.P. Leventis Conservation Foundation for supporting this work. Female song is widespread across bird species yet rarely reported. Here, we report the first observations and description of female song in the Cyprus Wheatear Oenanthe cypriaca and compare it to male song through the breeding season. Twenty-five percent of colour-ringed females were observed singing at least once, predominantly in April, compared to 71% of males that continued singing through the breeding period. We suggest that female song may have multiple functions in this species, but it may be especially important in territorial defence and mate acquisition. Publisher PDF

A field study was carried out for the first time in Kashmir Valley to investigate the population status and distribution of Ibisbill. The initial reconnaissance surveys conducted across Kashmir Valley, indicated that the Lidder River in district Anantnag and Sindh River in district Ganderbal harbor populations of Ibisbill. During the intensive study carried out in the river Sindh from September 2017 to August 2018, the mean population size was maximum (36±8.63) at Stretch I and minimum (3±1.35) at stretch II. The seasonal population of Ibisbill was maximum (25.66±18.44) in the autumn and minimum (10±9.35) in the winter. The present study indicated that river Sindh provides an ideal habitat for Ibisbill, and was most widely used by the bird. We recommend further intensive research studies on the lesser known aspects of ecology and biology of this enigmatic species for long term conservation planning in the region.

There is sparse and contradictory information concerning the migratory status and non-breeding range of the endangered Jankowski’s Bunting Emberiza jankowskii, precluding the possible development of conservation measures dedicated to protecting habitats occupied across the full-annual cycle. To unravel the migratory strategy and identify the non-breeding grounds of Jankowski’s Bunting, we collected feathers on breeding birds in Inner Mongolia, analysed their deuterium concentrations (δ2Hf) and produced probabilistic geographic assignments to origin to assess where these feathers were likely grown. We compared results from this exercise to current knowledge of the breeding and non-breeding range to evaluate likely moult origins thereby informing migratory connectivity in this species. Winter moulted feathers were not grown in the same isotopic environment than summer-grown feathers, attesting some non-breeding dispersive movements, and geographic assignments favour the hypothesis of a short-distance dispersion during the non-breeding season.

Timing is critical for species that migrate seasonally, as timing mismatches can lead to reduced reproductive success and population declines. We investigated the effect of breeding latitude on the migration timing of a long-distance migratory songbird (Purple Martin, Progne subis subis) by using light-level geolocators deployed across breeding sites between 26° and 53° latitude (n = 329). We used nesting data (1st egg dates; n = 28,165) to explore latitudinal patterns in the timing of breeding. Using generalized linear mixed models (GLMMs) we found that breeding latitude was highly associated with timing around the calendar, explaining population-level timing across both spring and fall migration. Populations breeding at more northern latitudes migrated later in fall (mean days/degree latitude = 2), in spring (mean days/degree latitude = 3), and nested later (days/degree latitude = 3) than populations breeding at more southern latitudes. Generalized additive mixed models (GAMMs) revealed significant non-linearity between breeding latitude and spring and fall migration timing, and the timing of nesting. In spring, the most northern breeders (> 40 degrees N) were more synchronous in their timing, departing their nonbreeding sites and arriving earlier at their breeding sites relative to their breeding latitude. These most northern breeders also had similar nest timing and fall migration departure timing. Breeding latitude was also associated with seasonal partitioning of migratory and sedentary periods. The most northern breeders spent 10% more time on fall migration, 2% more at wintering grounds, 1% more on spring migration, and 13% less time at their breeding sites. Our results support the notion that selection for timing at breeding latitudes can have year-round effects on the timing of seasonal events in long-distance migratory songbirds. Future studies should examine whether these timing patterns associated with latitude limit phenotypic responses to climate change.

Foraging behavior of Brown Rats (Rattus norvegicus) is commonly thought to be guided by olfactory cues. Here we tested the hypothesis that foraging Brown Rats eavesdrop on bird vocalizations to locate prey. We recorded calls of nestling Starlings (Sturnus vulgaris) with microphones sensitive in the sonic and ultrasonic range, respectively, and compiled clear begging calls into a single sound file (2-min long) which included the entire recorded sound range (0–100 kHz; Audio File 1). Sound analyses revealed a fundamental two-tone modulated sound centered around 3 kHz, a first and second harmonic at, respectively, 9 and 16 kHz, and bands of ultrasonic frequency components at 20, 25, and 37 kHz. We subjected Audio File 1 to low- and highpass-filtering, thereby producing a sonic-range only file (

The relationship between mistletoes and their host trees constitutes one of the unique host–parasite interactions in ecosystems. Most West African studies have reported on the parasitic nature of the relationship between Tapinanthus dodoneifolius mistletoes and Parkia biglobosa trees. However, there is little on bird species’ use and subsequent dispersal of the mistletoe on P. biglobosa, and consequently, we investigated aspects of this relationship in the present study. We conducted our study in Amurum Forest Reserve, located in the central part of Nigeria, from May to September 2017. The study area consists of a mosaic of savanna, gallery forest, and rocky outcrops. Of the bird community in this area, the yellow-fronted Tinkerbird Pogoniulus chrysoconus had the highest number of visits to T. dodoneifolius fruits, while the Senegal Eremomela Eremomela pusilla spent the most time foraging on the fruits. Four sunbird species were recorded feeding on T. dodoneifolius flowers for nectar; all but the Copper Sunbird Cinnyris cupreus were observed opening the flowers of T. dodoneifolius. Other bird species were recorded foraging on insects on T. dodoneifolius, and some simply perching on twigs or pecking on mistletoe fruits. This was a mutualistic relationship between the respective bird species and the mistletoe. This indirectly benefitted the parasitised host by attracting potential pollinators, seed dispersers, and insectivores for the host, hence, improving the rate of visitation to the host. These patterns of visitation behaviours highlighted the ecological importance of T. dodoneifolius within the reserve, particularly in enhancing the survival of other taxa within the reserve. Findings from this study contribute to developing more-nuanced conservation strategies for mixed high savannah habitat types across the tropics.

Obligate avian brood parasites depend on hosts for parental care, which in turn suffer fitness losses as a result of parasitism. Mechanisms by which brood parasitic cowbirds (Molothrus spp.) reduce host breeding success include the puncture (M. rufoaxillaris and M. bonariensis) or removal (M. ater) of the eggs of the host. Our working hypothesis is that the host eggs’ mechanical strength and their size and shape in species with higher frequency of parasitism covaries with the cowbird’s strategy to reduce host clutch size. Our results, obtained through phylogenetic analyses based on egg 2D geometric morphometry and eggshell mechanical and ultrastructural measurements, suggest that egg-puncturer behaviour has led to an increase in the strength of the host’s eggshell, which might make them more difficult to be pierced. We also characterized larger, more rounded and asymmetrical eggs in frequent hosts of M. ater, which might be more difficult to be removed. These interspecific host egg and shell traits were also positively affected by the frequency of parasitism, indicating that species-specific patterns of parasitic costs select for respective anti-parasitic defences in hosts.

SynopsisBirds with delayed plumage maturation exhibit a drab predefinitive plumage, often despite gonad maturation, before developing the definitive plumage associated with increased reproductive success. Manakins are a diverse clade of neotropical lekking birds with extreme sexual dichromatism, radical sexual displays, and a unique diversity in the predefinitive plumages of males across species. Here, we provide the first full review of the natural history of manakin predefinitive plumages as the basis for qualitatively addressing the six major hypotheses about the production and function of predefinitive plumages. We find little evidence to support the possibilities that manakin predefinitive plumages are directly constrained by inflexible molt schedules, resource limitations to definitive coloration, or hormonal ties to reproductive behaviors. There is little evidence that could support a crypsis function, although direct experimentation is needed, and mimicry is refuted except for one unusual species in which predefinitive males sire young. Instead, evidence from a handful of well-studied species suggests that predefinitive plumages help young males explicitly signal their social status, and thereby gain entry to the social hierarchies which dictate future reproductive success. Our conclusions are especially influenced by the unique fact that males of at least 11 species throughout the family exhibit multiple predefinitive plumage stages with distinctively male patches. For each hypothesis, we highlight ways in which a better knowledge of female and young male birds offers critical opportunities for the use of manakins as a model clade.

Antibody mimetics may be used for various biomedical applications, especially those for which conventional antibodies are ineffective. In this study, we developed a smaller molecular chicken IgY mimetic peptide (IgY-peptide) based on the complementarity-determining regions (CDRs) of the anti-canine parvovirus (CPV) IgY-scFv prepared previously. The mimetic peptide showed no cross-reactivity with canine distemper virus (CDV) and canine coronavirus (CCV) and showed excellent protective properties for Crandell-Rees Feline Kidney (CRFK) cells against CPV. This study is the first attempt to develop a mimetic IgY-peptide and demonstrates the ease and feasibility in generating such a novel antibody-like functional molecule for biomedical purposes.

Purpose: To describe early symptoms of chronic radiation syndrome (CRS) which is of utmost importance for diagnosing this rare radiation pathology in man. Material and methods: The paper presents the findings of retrospective analysis of early clinical manifestations of chronic radiation syndrome (CRS) based on the data of a long-term medical follow up of the residents of the Techa riverside communities. Mean doses of postnatal exposure to red bone marrow in patients with CRS calculated with TRDS-2016D were 698.8±18.2 mGy, maximum doses were 3 603.9 mGy. Results: Clinical picture of the CRS at the early stage was characterized by a set of non-specific changes including hematological, immune, neurological, and endocrine ones, as well as impairment of functions of a number of internal organs. The above-mentioned CRS symptoms developed in a certain sequence and depended on dose rate and absorbed dose to the organs. Prior to the development of a full-scale CRS clinical picture patients had a decrease in olfactory and taste thresholds, in vibration sensitivity, and changes in systemic immunity. Impairment of hematopoiesis, nervous and endocrine systems were also noted even at the early stage of CRS. Initial CRS changes were moderate and transient. The analysis of early CRS symptoms allows assuming that early CRS stage is a dysregulation pathology that is caused initially by radiation-induced disorders of immunohematopoiesis, nervous and endocrine systems. Visceral changes at the early CRS stage are secondary and functional. If exposure is terminated, they are reversible. However, if exposure continues at doses high enough to cause morphological changes in organs and tissues (dystrophy, fibrosis, hypoplasia, etc.), CRS course worsens and becomes irreversible. Conclusion: It was demonstrated that CRS diagnosis at the early stage is very complicated. The key issue is to analyze the relationship of specific CRS symptoms development and dose rate and absorbed organ doses.

Dispersal constitutes one of the main processes that shape population genetic structure and dynamics. Combining a capture-mark-resighting methodology and molecular genetics analyses, we studied the natal dispersal behaviour of House Wrens (Troglodytes aedon bonariae) inhabiting a naturally fragmented habitat in south temperate Argentina. Based on data collected over 12 breeding seasons (2005–2016), we tested if males and females differ in natal dispersal behaviour at different spatial scales. At local scale (within study sites), both resighting of banded individuals and genetic analysis showed that females dispersed greater distances than males. At a broader spatial scale (between study sites) resighting of banded individuals could not verify that females were the dispersing sex since long-distance dispersal was rare. However, genetic analyses revealed paradoxical evidence: while the females of populations separated by more than 5 km showed slight but significant genotypic differences among them, males showed genetic differences at a greater distance (> 16 km). Given that genetic analyses can provide evidence of both historical and present-day dispersal the observed genetic differentiation does not necessarily imply that the sex dispersal pattern is reversed at a regional scale. We propose that females have a higher probability of acquiring a partner/territory at closer distances due existing male-biased population sex ratio caused but higher female mortality. Also, although males are less likely to disperse, when they do, they must travel greater distances to find a suitable territory or mate. Such movements would prevent the occurrence of genetic differences among male populations.

SummaryThe carrasco is a dense, shrubby vegetation type that covers the higher parts of table-top mountains in north-eastern Brazil. The vegetation of this phytophysiognomy is often considered to have biogeographical and ecological affinities with the cerrado of Central Brazil, but the biogeographical affinities of its avifauna remain unclear. In recent years, deforestation due to local economic activities has been particularly severe in some carrasco-dominated landscapes. In 2013, we initiated avian surveys at the Fazenda Pau D‘Arco, a privately owned property located on top of the Araripe Plateau, to evaluate the effects of a legal forest management program on the avifauna. Here, we present the results of four years of avian inventories to: i) characterize a well-preserved patch of carrasco vegetation; ii) assess avian biogeographical affinities of this vegetation type; iii) identify associations between managed/unmanaged areas and bird species; and iv) provide baseline data for future avian monitoring studies. Using different survey methods, we provide a list of 148 bird species, including several dry-forest specialists and caatinga endemics. Biogeographically, the avifauna of the carrasco represents a subsample of the Caatinga dry forest, lacking cerrado elements. Forest management significantly affected the distribution of several bird species in the study area. We found that 1/5 of the species (24) recorded during our standardized surveys were significantly associated with either unmanaged (14 species) or managed (10 species) areas. Species such as the Ceará Leaftosser Sclerurus cearensis, a globally vulnerable species, have only been detected in non-managed areas and therefore can be negatively affected by the management program. We also present data on 16 avian taxa with ecological and conservation concerns. By presenting a fairly complete and documented list of the avifauna, we characterize the carrasco avifauna and offer the tools to evaluate the effects of forest management on this poorly known vegetation type.

Okinawa Island, Japan, is a globally important biodiversity hotspot. Three endemic bird species, Okinawa rail (Hypotaenidia okinawae), Okinawa woodpecker (Dendrocopos noguchii), and Okinawa robin (Larvivora namiyei), are found only in the Yambaru region of the northern part of Okinawa Island. In order to conserve endemic species, it is important to determine the effect of alien species on endemic species. We conducted playback surveys four times every three years from 2007 to 2016 to evaluate the recent distribution of these three forest-dwelling bird species during the breeding season. Then, the association between the numbers of detections of these three species with the invasive mongoose density and the hardwood forest area was evaluated with a generalized additive mixed model (GAMM). The results showed that the distribution areas of these bird species have been recovering since the 2007 within the small Indian mongoose (Urva auropunctata) controlled area. The GAMM results showed that these bird species were abundant in areas with fewer small Indian mongooses and larger areas of hardwood forests. Thus, the mongoose had a negative impact not only on the flightless rails but also on the woodpeckers and the robins. In recent years, most of the old-growth forests have been designated as protected forests, and large-scale logging is no longer taking place in Yambaru. Eradication of the mongoose is particularly important for the conservation of these three endemic bird species.

In migratory birds, constraints due to breeding are relaxed during the non-breeding season and thus, social behaviours and spatial associations are potentially more directly coupled to food resources and habitats. Use of space and territorial behaviour has rarely been studied in Afro-Palearctic migrants. Variation in strategies could exist among species within the same habitat because of differences in foraging, diet and microhabitat. We compare use of space and association with conspecifics in Common Chiffchaffs Phylloscopus collybita and Subalpine Warblers Sylvia cantillans at a non-breeding site in northern Senegal using radio telemetry and playback experiments. Home ranges of Chiffchaffs were larger and overlapped more than those of Subalpine Warblers. Though Chiffchaffs were often close together, we found no signs of spatial association among individuals in either species. Chiffchaffs showed no clear pattern of territorial response to conspecific song; whereas, playback elicited a territorial response in most Subalpine Warblers. Our results suggest species-specific differences in use of space that might reflect differences in foraging ecology and microhabitat.

Songbird vocalizations serve diverse functions including territory defence against neighbouring conspecific animals. In tropical and south-temperate regions, it is commonplace for both female and male songbirds to sing solo songs and coordinated vocal duets to defend their territories. The Area de Conservacion Guanacaste in Costa Rica is the site of an ambitious conservation effort to protect and regrow tropical dry forests; it consists of a mosaic of regenerating and mature forest patches, presenting a special opportunity to study the effect of different numbers of neighbours on male and female wrens living in these fragmented forests. We analyzed recordings of Rufous-and-white Wrens (Thryophilus rufalbus) over a 17-year period, focusing on vocal behaviour and variation in the number of territorial neighbours within the fragmented landscape in the conservation area, and on diel and seasonal variation in female and male song. We hypothesized that the number of conspecific neighbours would influence vocal behaviours, including female and male solo song rate, duet responsiveness rate, repertoire use, and song-switching rate. For females, we found that wrens change song-types more often in areas with more neighbours, whereas the other aspects of female vocal behaviour did not vary with the number of neighbours. For males, we found no aspect of vocal behaviour that varied with the number of neighbours. For both sexes, we found variation in vocal behaviours with time of day and time of year, in keeping with previous research. Our results underscore the idea that we must explore female and male birds independently, because the sexes may respond differently to external factors. We did not find strong links between wren vocal behaviour and variation in the number of neighbours, yet we encourage further behavioural studies on vocal behaviour of birds with varying numbers of neighbours in fragmented landscapes.

Globally, but especially in Africa, increasing human populations and anthropogenic land-use change are generally affecting diversity negatively. Urban environments in southern Africa typically comp...

Anthropogenic food availability is influenced by short-term fluctuations in human presence, especially in core urban areas. Few studies have explored responses to such day-to-week fluctuations, specifically on body mass and body condition of urban birds. Here, we investigated non-breeding body mass maintenance and body condition in Red-winged Starlings Onychognathus morio resident at the University of Cape Town, Western Cape, South Africa, in relation to the proportion of impervious surfaces within their home ranges (‘built-up index’). We hypothesised that the built-up index correlates with the starlings’ ability to maintain mass, which is mediated by anthropogenic food availability. In a community science project focused on the university campus, we estimated home range sizes and combined these data with systematic behavioural observations (focals), transects to estimate anthropogenic food availability and repeated body mass measurements. Individual starlings with more built-up home ranges were heavier; they were also heavier and in better body condition on high human presence days (weekdays in term time). We found no relationship between the amount of anthropogenic food available or the proportion of anthropogenic food consumed and built-up index, nor between the times spent foraging or foraging efficiency and built-up index. However, anthropogenic food availability was higher on high human presence days when starlings also consumed more anthropogenic food and tended to spend less time foraging, compared with low human presence days (weekends and vacation). There is growing concern that anthropogenic food could have negative consequences during the breeding season, when parents might be provisioning ‘junk food’ to their offspring. This study provides additional understanding of urban impacts on avian species and the role of anthropogenic food.

Among the broad diversity of songbird vocalisations, song can serve a wide range of different functions depending on the species and context. In many species, aggressive motivation has often been linked with the use of fast repeated series of elements typically referred to as trills. However, only a few studies explored the role of this specific component in species with a large repertoire and high song complexity. Here, we investigate the potential role of trills in the territorial vocal response of males Thrush Nightingale (Luscinia luscinia), a species with complex songs characterised by the frequent use and diversity of their trills. We performed playback experiments simulating territorial intrusion to test if trills signal aggressive motivation in this species. If so, we expected tested males to respond by changing their trill rate or frequency of trill use in songs, and/or using different trill types than before the stimulation. Contrary to our expectation, males did not modify their trill rate or differed in trill type use before, during or after playback. There was a tendency for decrease in trill duration and the number of elements in the trills during the playback stimulation, reflecting to some extent the overall use of shorter songs by males during that stage of the experiment. Altogether, our study does not support the role of trills as motivation signals for territory defence in Thrush Nightingales, but advocates for more research on their potential roles in signalling other information.

Among the approximately 40 species of mammals described in Historia naturalis Brasiliae by Willem Piso and Georg Marcgrave, the identity of the monkey “cagui major” has been one of the most controversial. Authors have identified Marcgrave's “cagui major” as a tamarin, a saki monkey, a squirrel monkey, a titi monkey and even as an Old-World monkey. Based on a watercolour, probably related to the original illustration that served as basis for the “cagui major” woodcut, we confirm that it depicts a titi monkey ( Callicebus). By comparing the pelage characteristics shown in the drawing and some measurements and pelage characteristics described in Historia naturalis Brasiliae, we confirm that the species depicted was Callicebus melanochir that occurs today in southern Bahia and northeastern Minas Gerais states, outside the range of the Dutch possessions in Brazil.

Background Large woodpecker species with stable territories, specialized diets and narrow habitat choices, such as the Magellanic Woodpecker (Campephilus magellanicus), are expected to adjust their movements based on the distribution of available resources within territories. Thus, Magellanic Woodpeckers should concentrate foraging activity in areas of higher quality, a behavior consistent with the area-restricted search (ARS) behavior. Although previous studies have deepened the understanding of how Magellanic woodpeckers select habitats, the assessment of ARS behavior would contribute to the identification of feeding areas important for their conservation and habitats hindering their movement. Methods We addressed the independent effects of tree senescence, forest succession, stand composition and open habitats on the adoption of area-restricted search (ARS) behavior in Magellanic Woodpeckers in a heterogeneous landscape dominated by southern beech forest in southern South America. Using GPS relocations from 24 woodpeckers, we estimated the First-Passage Time (FPT), a measure of the time individuals remain in a given area, with longer FPT values indicating the adoption of an ARS behavior. We determined the effects of habitat variables on FPT using a methodological framework based on Linear Mixed Effect models and a randomization procedure intended to reduce spatial autocorrelation arising from consecutive circles whose areas tend to be overlapped along trajectories. Results Averaged model coefficients showed that woodpeckers spent less time in sites dominated by the Antarctic beech (Nothofagus antarctica) and partially covered by open habitats. Conversely, FPT increased in stands and home ranges where tree senescence was higher. Conclusions The adoption of the ARS behavior in Magellanic Woodpecker is explained by forest composition, avoidance of open habitats and tree senescence. Our results suggest the conservation of Magellanic Woodpeckers in heterogeneous landscapes involve retention of senescent trees and restoring open areas in order to reduce edge habitat.

The plumage of birds plays an essential role in thermal insulation and influences the heat tolerance of birds. These plumage functions are mainly determined by the number and the density of feathers, but it is unclear how feather density responds to environmental changes in wild populations. In urban birds, both high temperature and limited food could generate changes in plumage traits. To investigate the effect of urbanization, we compared the number of feathers in nestlings between urban and forest Great Tits Parus major using a novel non-invasive method. We showed that urban nestlings have fewer feathers than forest nestlings at 6-9 days old. Although the density of feathers was slightly higher in urban nestlings, this was the result of the smaller size of their feather tracts. We suggest that the reduced feather number may be the result of either adaptation to higher urban temperatures, constrained feather development due to limited optimal nestling-food sources in urban environments, or both. Concentrating body feathers in a reduced tract area may also help birds to adapt to higher urban temperatures because this can increase the relative size of bare body surfaces which may facilitate heat dissipation. We suggest several possibilities for future studies that would help to disentangle the underlying mechanisms responsible for the observed patterns.

When environmental conditions change, species usually face three options: adaptation, range shifts, or extinction. In the wake of climate change, it is generally believed that range shifts are the norm in mobile species such as birds, resulting in poleward range shifts. The European Bee-eater is a predominantly Mediterranean species which has expanded its range to higher latitudes over the last decades. Germany in particular has seen a surge in breeding pairs and foundation of new colonies. However, while many experts suggest climate warming as the main driver behind this range expansion, an explicit quantification remains open. Here, we use an ensemble modelling approach to study the recent climatic niche suitability of the European Bee-eater across Europe with a special focus on Germany and project its predicted Palaearctic breeding distribution onto the year 2050 using two global circulation models and two representative concentration pathways. Models were able to predict the current European range of the species with some underestimated areas in Central and Eastern Europe, depending on the selected model. We found a strong relationship between climatic suitable areas and estimated population sizes across European countries that is reflected in most algorithms. In particular, the German population size is in line with climate suitability in the country suggesting a strong climate–population relationship and a high degree of niche filling. Most future predictions point to an ongoing northward expansion of the species while areas in Southern Europe and the Maghreb area remain largely suitable. The strong climate–population relationship makes the European Bee-eater an appropriate indicator species for climate change. Yet the high variability of modelling algorithms also call for caution of using these techniques without careful inspection.

High human population growth and rapid urbanisation, particularly in Africa, have led to an increased interest in the impacts of this land-use change on bird communities. The African Bird Atlas Pro...

The European honey buzzard Pernis apivorus is a summer visitor in Europe, wintering mostly in West-central Africa. Previous studies concerning timing of autumn migration in relation to sex groups provided contrasting results. In particular, a field survey made in southern Sweden did not report differences in timing, while a satellite study via GPS tracking on six adults, three males, and three females, revealed that the latter departed earlier. The aim of this 4-year study is to further investigate the timing of autumn migration in this species carrying out observations at the Strait of Messina, a bottleneck located along the Central Mediterranean flyway, between August 10th and September 30th 2016–2019. Adult European honey buzzards concentrated the passage between late August early September, with females passing on average 5 days earlier than males. It is suggested that a different role of sexes concerning exhibition of territorial displays during the late breeding season, would explain differences between sex groups in timing of both moult and autumn migration.

L’étude de la décomposition des carcasses de vertébrés est généralement réalisée lorsque les insectes nécrophages sont actifs ; au printemps, en été et en automne. Mais que se passe-t-il si un animal meurt quelques jours avant l’arrivée des températures froides et de la neige ? Pour répondre à cette question de façon préliminaire, une carcasse de porcelet (30 kg) a été installée dans un boisé de feuillus de novembre 2012 à mai 2013. Pour documenter le processus de décomposition, la carcasse a été photographiée et les insectes échantillonnés à intervalles réguliers. Les résultats démontrent que les températures froides ont perturbé les étapes de décomposition normalement observées (corps frais, gonflé, putréfié, post-putréfié et sec/restes) lors des saisons plus chaudes. En outre, en raison de fluctuations climatiques, seules deux (corps frais/congelé et corps putréfié) des trois premières étapes ont été observées. Les stades post-putréfié et sec n’ont pas été documentés puisque l’expérience a pris fin très tôt au printemps. En novembre, seules 6 espèces de diptères appartenant à 5 familles ont été observées en très petits nombres. Enfin, les redoux des mois de mars et avril ont permis de capturer des coléoptères (8 espèces de 4 familles) et des diptères (21 espèces de 11 familles), dont des Heleomyzidae qui ont été parmi les premiers à visiter la carcasse., Vertebrate carcass decomposition studies are typically conducted in spring, summer or autumn, when necrophagous insects are most active. But what happens if an animal dies just before the onset of colder weather and the arrival of snow? To provide preliminary answers, a domestic piglet carcass weighing 30 kg was installed in a deciduous woodland in November 2012 and studied until May 2013. The carcass was photographed and examined for insects at regular intervals. The decomposition stages normally observed during warmer seasons (i.e., fresh, bloated, active decay, advanced decay and dry/remains) were disrupted by the cold. Furthermore, because of the weather conditions, only the fresh/frozen and active decay stages of the usual first three stages of physical decay were observed. The advanced decay and dry/remains stages were not documented because the experiment ended before these occurred. In November, small numbers of 6 species of Diptera belonging to 5 families were collected from the carcass. Warmer weather in March and April increased insect activity and 8 species of Coleoptera belonging to 4 families and 21 species of Diptera belonging to 11 families were recorded, with members of the Heleomyzidae being among the first to visit the carcass.

Site fidelity after successful nesting and site shift after nest predation (win–stay, lose–shift) is a well-documented adaptation to spatially heterogeneous and temporally auto-correlated predation risk. However, site shift even after a successful nesting (win–shift) may become a better tactic than site fidelity (win–stay), if a successful nest site becomes more risky until the next nesting opportunity, and if new low-risk nest sites regularly appear. Correspondingly, selecting a new non-used nest site may become a better tactic than selecting one previously used successfully by a conspecific. I studied this dynamic by focusing on nest cavities that may be available for many years, and using nest boxes to allow an experimental design. At localities where Boreal Owls (Aegolius funereus) had nested successfully, a dyad of nest boxes was made available each year, one box in the original nest tree and one in a new tree for the season, each containing either old nest material from the successful nesting or new wood shavings. Boreal owls were more likely to select the box in the new tree when more years had elapsed since the successful nesting and since a box was installed in the original nest tree, independent of box content. The pattern of selection differed between young and old individuals for males, but not females. Young males based their selection of nest tree mainly on box content, while old males based it on time elapsed since the successful nesting in the original nest tree and how long a box had been present there. The probability of depredation of Boreal Owl nests by Pine Marten (Martes martes) has previously been found to increase with cavity age and number of nesting seasons elapsed since the previous successful nesting. This pattern of nest predation thus predicted the pattern of nest site selection found.