Asio Otus Research Articles

Prevalence and Antimicrobial Resistance of Campylobacter jejuni and Campylobacter coli in Wild Birds from a Wildlife Rescue Centre.

Simple SummaryWildlife may be zoonotic carriers of pathogens. The aim of this paper was to investigate the presence of Campylobacter (C.) jejuni and C. coli, which are responsible for enteric syndromes and sometimes extraintestinal diseases in humans, in wild birds housed at a wildlife rescue centre. Sensitivity to antibiotics was also investigated in the detected strains. Two hundred and nine birds belonging to 33 different species were considered in the study. Campylobacter was found in 52 birds (24.88%), mainly in omnivorous species. In terms of housing conditions, the infection rate was higher in birds housed in indoor (57.14%) than in outdoor aviaries (31.74%). Interestingly, Campylobacter was not detected in some species whose mean temperature body was below 40 °C or higher than 42.2 °C. All detected strains were C. jejuni except for three C. coli that were identified in Long-eared Owls. The most commonly found antibiotic resistance was against drugs such as trimethoprim/sulfamethoxazole, ciprofloxacin and enrofloxacin. Multi-drug resistance against two or more antibiotics was also detected. The findings of the study highlight the relevance of increasing biosecurity measures at the wildlife rescue centres to reduce health risks to staff involved in wildlife management.Climate change, excessive exploitation of agricultural land which reduces natural habitats, wildlife shooting, and the use of pesticides all cause difficulties for wildlife, with considerable numbers of animals being brought to wildlife rescue centres. Although the efforts of staff involved in wildlife management at these centres usually focus on therapeutic treatments to reintroduce them into the wild, the monitoring of pathogens that may be transmitted to humans is of relevance. Campylobacter (C.) jejuni and C. coli are frequently carried by animals without inducing clinical signs and are responsible for enteric disorders and more rarely extra-intestinal disease in humans. Farm species and poultry, in particular, are the main reservoirs of C. jejuni and C. coli, but wild animals may also be carriers. The aim of this paper was to investigate the presence of C. jejuni and C. coli in wild birds housed at a wildlife rescue centre and to evaluate the sensitivity of the detected strains to antibiotics. Campylobacter was found in 52 out of 209 (24.88%) birds from 33 different species. C. jejuni was more prevalent, while C. coli was only detected in three Long-eared Owls (Asio otus). The incidence of the infection was particularly high (72.22%) among omnivorous species. Infection rates were higher in birds housed indoors (57.14%) than outdoors (31.74%). Moreover, Campylobacter was not detected in species whose mean temperature body is below 40 °C or higher than 42.2 °C. The most common antibiotic resistance in the tested strains was against trimethoprim/sulfamethoxazole, ciprofloxacin and enrofloxacin. In addition, multi-drug resistance was also found. The results highlight the need to increase biosecurity measures at rescue centres so as to reduce health-related risks to workers involved in wildlife management.

Habitat-Patch Occupancy of Western Screech-Owls in Suburban Southern California

Many predators can adapt to human-altered habitats, but varying responses to human activity mean that the findings of studies of a species in one region may not apply even to related species at other locations. The Eastern Screech-Owl (Megascops asio) has been extensively studied in suburban environments, but comparatively little research has investigated to what extent the closely related Western Screech-Owl (M. kennicottii) persists in developed areas. I studied Western Screech-Owl occupancy in the town of Alpine in the foothills of San Diego County, California, finding the species at the majority of sites sampled, more likely in larger wooded patches and in those adjacent to undeveloped chaparral. The distance to and size of nearby wooded patches did not statistically influence occupancy. This study confirmed that the Western Screech-Owl can persist in suburban residential areas as does its eastern relative. Ensuring that patches of woodland remain larger than the minimum modeled threshold for the Western Screech-Owl’s occupancy, 4.2 ha, will be important for its persistence in the suburban sprawl of Alpine.

Taphonomical and palaeoenvironmental analyses of the microvertebrate fossil material from the Late Pleistocene cave of Kalamakia (Mani peninsula), Greece

ABSTRACT The present study focuses on the microvertebrate fossil material retrieved from the three fossiliferous units of Kalamakia cave dating from ca. 90–25 kya BP, to identify the accumulation agents of the assemblage and the processes that affected it post-depositionally. This was done through the quantification of specific indices described in the literature concerning breakage, digestion and other types of modifications observed upon the surface of the specimens. Furthermore, the Taxonomic Habitat Index was calculated to reconstruct the possible habitat types in the surrounding area. Regarding the results on taphonomy, significant amounts of post-depositional breakage were observed, possibly resulting from trampling and, secondarily, modifications from the occasionally naturally occurring high humidity within a cave. The main accumulators of the microvertebrate assemblage seem to have been barn owls either independently or jointly with long-eared owls and/or owlets. Concerning the habitats possibly present in the area, the existence of mixed habitats varying between relative expansions of shrublands, grasslands, rocky areas and (limited) deciduous forests was identified, while the occasional presence of water bodies was also revealed. Shifts between the percentages of different habitats were not great but could be correlated with climatic events within a geochronological context.

Use of Feathers from Birds that Collided with Vehicles to Monitor Heavy Metal Contamination in Western Khorasan Razavi, Iran.

In the present study, lead, zinc and copper concentrations in the feathers of Common kestrel (Falco tinnunculus), Eurasian magpie (Pica pica), Common buzzard (Buteo buteo), Crested lark (Galerida cristata), Eurasian hoopoe (Upupa epops), Little owl (Athene noctua), Long-eared owl (Asio otus), Eurasian eagle-owl (Bubo bubo) and Long-legged buzzard (Buteo rufinus) from Sabzevar and Neghab, Khorasan Razavi of Iran were measured. Almost all of the specimens were obtained from birds that had collided with vehicles or were unable to fly. There were no significant differences in metal concentrations between adult and juvenile, diurnal and nocturnal raptors and species with different diets. Elemental concentrations were lower than toxicity threshold values, so exposure to these elements does not appear to pose a health risk to the studied species. It should be noted that this study was the first study of metals in Galerida cristata, Asio otus and Buteo rufinus.

Anatomical study of the scleral ring and eyeball of the long-eared owl (Asio otus) with anatomical methods and diagnostic imaging techniques.

BackgroundThe scleral ring in birds consists of ossicles that are fixed as small plates by cartilage joints and have no articulation to other parts of the skeleton.ObjectiveDue to inadequate examination of the scleral ring anatomy and its specific form in owls, this study aimed to investigate the exact structure of the scleral ring and some morphometric characteristics of the eyeball in a long‐eared owl (Asio otus).MethodsThe eyes of 20 alive and 10 dead male and female owls were examined. In addition to common anatomical methods, computed tomography scans and radiographic and ultrasonographic imaging techniques were used in this study.ResultsThe structure consisted of 15 ossicles. In the ventral part of the ring, these tubercles were observed in the scleral rings of all owls; in each ring, there were four bones with these tubercles. Additionally, there was no significant difference between the left and right eye parameters. Most ocular parameters in female owls were larger than those in males, but in the case of some parameters, such as optic nerve length and optic nerve sheath diameter, this difference was not observed.ConclusionsAccording to this study, the scleral ring in the Asio otus has anterior and posterior parts, and the lens is in the immediate vicinity of the anterior part. The right and left scleral rings and eyeballs are bilaterally symmetrical in terms of the shape, size, and number of ossicles that form the ring.

Risk Factors and Prognosis for Humeral Fractures in Birds of Prey: A Retrospective Study of 461 Cases from 2000 to 2015.

The objectives of this retrospective study were 1) to characterize humeral fractures in raptors at a rehabilitation program, 2) to determine risk factors for closed and compound humeral fractures in the raptors, and 3) to investigate prognostic factors for humeral fractures in raptors. Of the 6017 birds of prey admitted over 15 years to the Université de Montréal raptor rehabilitation program, 461 birds presented with a humeral fracture. The highest occurrences of humeral fractures were documented in short-eared owls (33%; Asio flammeus), Northern hawk-owls (24%; Surnia ulula), long-eared owls (20%; Asio otus), and Northern harriers (19%; Circus hudsonius). Humeral fractures were more common in males, and species from the intermediate weight group (300 g to 1 kg) were more likely to have compound humeral fractures than birds from the lower and higher weight groups. Humeral fractures of the middle and distal third of the bone were diagnosed as compound more often than fractures of the proximal third. A correlation between the occurrences of humeral fractures and the relative average width of the humerus for each species was observed and suggests that species with slender humeri have an increased likelihood of compound humeral fractures. Following the triage criteria used at this rehabilitation program, surgical (119 birds) or nonsurgical (77 birds) treatments were attempted. Release rate for birds without concomitant conditions in which a treatment was attempted was 39.3% (59/150) and did not significantly differ between closed and compound fractures, which suggests that the triage criteria used for compound fractures in this program were adequate. Our findings emphasize that raptors should not be systematically euthanatized when presented with compound humeral fractures to a rehabilitation facility.

Causes, temporal trends, and the effects of urbanization on admissions of wild raptors to rehabilitation centers in England and Wales.

Data from wildlife rehabilitation centers (WRCs) can provide on‐the‐ground records of causes of raptor morbidity and mortality, allowing threat patterns to be explored throughout time and space. We provide an overview of native raptor admissions to four WRCs in England and Wales, quantifying the main causes of morbidity and mortality, trends over time, and associations between threats and urbanization between 2001 and 2019. Throughout the study period, 14 raptor species were admitted totalling 3305 admission records. The Common Buzzard (Buteo buteo; 31%) and Tawny Owl (Strix aluco; 29%) were most numerous. Relative to the proportion of breeding individuals in Britain and Ireland, Peregrine Falcons (Falco peregrinus), Little Owls (Athene noctua), and Western Barn Owls (Tyto alba) were over‐represented in the admissions data by 103%, 73%, and 69%, respectively. Contrastingly Northern Long‐eared Owls (Asio otus), Western Marsh Harriers (Circus aeruginosus), and Merlin (Falco columbarius) were under‐represented by 187%, 163%, and 126%, respectively. Across all species, vehicle collisions were the most frequent anthropogenic admission cause (22%), and orphaned young birds (10%) were most frequent natural cause. Mortality rate was highest for infection/parasite admissions (90%), whereas orphaned birds experienced lowest mortality rates (16%). For one WRC, there was a decline in admissions over the study period. Red Kite (Milvus milvus) admissions increased over time, whereas Common Buzzard and Common Kestrel admissions declined. There were significant declines in the relative proportion of persecution and metabolic admissions and an increase in orphaned birds. Urban areas were positively associated with persecution, building collisions, and unknown trauma admissions, whereas vehicle collisions were associated with more rural areas. Many threats persist for raptors in England and Wales, however, have not changed substantially over the past two decades. Threats associated with urban areas, such as building collisions, may increase over time in line with human population growth and subsequent urban expansion.

Hard Ticks (Ixodidae) from Wildlife in Liguria, Northwest Italy: Tick Species Diversity and Tick-Host Associations

Simple SummaryWildlife may carry ticks that can transmit pathogens to domestic animals and humans. Tick species from hunted and accidentally found dead wild animals were identified in the framework of a Regional Plan of Monitoring and Surveillance of Wildlife health in the Liguria region, northwest Italy. The results are presented to provide updated information on the tick species in the region and on their host preference. A total of 819 ticks, removed from 259 animals, were found and identified as belonging to five different species. Ixodes ricinus was the most frequent species, especially in roe deer and fallow deer, whereas Dermacentor marginatus was more specifically associated with wild boar. Wild animals are useful for characterizing and monitoring the tick population in an area, and these data will help in structuring control strategies.Hard ticks’ geographical distribution and abundance are influenced by wildlife population. This work presents the results of the identification of ticks retrieved from wild animals in the framework of a Regional Plan of Monitoring and Surveillance of Wildlife health. The frequency of distribution of ticks in different hosts and their geographical patterns were also investigated. Ticks were collected from game animals (Sus scrofa, Capreolus capreolus, Dama dama, and Rupicapra rupicapra) during two hunting seasons (2018–2019 and 2019–2020) in the four provinces of the Liguria region in northwest Italy. In the same period, ticks were also collected from carcasses of Vulpes vulpes, Canis lupus, Meles meles, and Asio otus received for necropsy. Tick species were identified according to taxonomic keys. A total of 819 ticks, removed from 259 animals, were found and identified. Overall, Ixodes ricinus was the dominant species (62.6%), followed by Dermacentor marginatus (24.5%), Rhipicephalus sanguineus s.l. (12.5%), Haemaphysalis punctata (0.2%), and Ixodes hexagonus (0.1%). I. ricinus was also the prevalent species in roe deer and in fallow deer and the only species collected from the three wolf carcasses examined. In contrast, D. marginatus was the dominant species in S. scrofa. This last tick species was also more frequent in one province (Imperia), whereas Ixodes spp. were more common in another one (Savona). Wild animals proved to be useful for characterizing and monitoring tick population.

A Survey of Sex Ratios of Raptors at a Rescue Center in China

ABSTRACT The sex ratio is an important concept in estimating population demography, and such data could contribute to both theoretical research and conservation. Although numerous studies have analyzed the sex ratios of raptors in the wild, few studies have focused on the sex ratios of raptors in wildlife rehabilitation facilities. Here, we report the results of polymerase chain reaction (PCR)-based sex identification of raptors brought to the Beijing Raptor Rescue Center in 2018–2020. This rescue center is located in eastern China, on a major migratory route for raptors in East Asia. We identified the sex of 646 individuals (belonging to 29 species) using two sets of primers, and analyzed the sex ratios of five species with a sample size >30 individuals. Generally, the sex ratios differed among species: the sex ratio of Eurasian Kestrels (Falco tinnunculus) was skewed toward males (P = 0.006), while the sex ratio of Eurasian Sparrowhawks (Accipiter nisus) was skewed toward females (P = 0.024). The sex ratio of Long-eared Owls (Asio otus) tended to be female-biased (P = 0.058). There was no significant bias of sex ratio in Oriental Scops-Owls (Otus sunia) or Amur Falcons (Falco amurensis). We discussed several possible reasons that could drive the biased sex ratios of raptors brought into rehabilitation centers. Our findings could be helpful for future studies on sex identification of raptors and conservation efforts.

Myological variation in the hindlimb of three raptorial birds in relation to foraging behavior

Raptors share a common predatory lifestyle, but are different in food preferences and hunting behavior. The grip force and talons' grasping capabilities are fundamentally crucial for subduing and killing their prey to feed, but the abilities and differences to generate force are less known. In this study, the entire pelvic muscles were dissected with the muscle mass and fibre length measured and physiological cross-sectional area counted in the Common Kestrel (Falco tinnunculus), Eurasian Sparrowhawk (Accipiter nisus), and Long-eared Owl (Asio otus). Statistical tests were performed to explore the possible differences in architectural parameters among species. These species were same in distributing the greatest proportion of muscle mass to the shank region and the digital flexor functional group, allocating more than 60% muscle mass in relation to total single leg muscle mass to the same seven individual muscles including flexor digitorum longus (FDL), flexor hallucis longus (FHL), and tibialis cranialis (TC) which are three major muscles responsible for talon closure. Interspecies differentiations were most present in the shank and tarsus instead of other regions of the leg, which might reflect their difference in hunting mode and foot use. Greater force-generation capacity of FHL and some anatomical features suggest that digits 1 and 2 work together as an efficiently vise-like set, playing more critical role than digits 3–4 in foraging of diurnal raptors but to a different degree. In accordance with zygodactyl foot morphology, each digit of the Long-eared Owl plays a subequal role when hunting, evidenced by anatomical and architectural features. Because of its unique insertion to the base of the pygostyle, the striking numerical difference in the development of M. caudofemoralis was possibly related to raptors’ flight behavior and feeding ecology. Concluded from anatomical and architectural aspects, the similarities and differences of the hindlimb musculature were correlated to common predatory lifestyle and different foraging behaviors in three raptor species. These results illustrated the underlying myological basis for the functional capacities of the leg muscles and may provide additional information useful in further biomechanical investigation and computer simulation.

What is for dinner? Qualitative and quantitative data regarding small mammal species identified in pellets of long-eared owl (Asio otus) from Cluj-Napoca

Analysis of pellets provides information on the prey distribution, abundance, behavior and trophic relationships between Strigiformes and small mammals. By analyzing the skulls from long-eared owl (Asio otus) pellets, collected from a colony located in the Mercur Park, in Cluj- Napoca, Romania, we aimed to identify the small mammal species and to compare the results with available ones from another study conducted 2 years ago in the same area. During 7 collecting campaigns (November 2018 to March 2019) in 538 pellets a total of 1290 skulls were identified. Over the study period, the colony increased from 10 to 40 birds. Six species of small mammals were identified: the field striped mouse (Apodemus agrarius), the yellow-necked mouse (Apodemus flavicollis), the wood mouse (Apodemus sylvaticus), the European water vole (Arvicola terrestris), the field vole (Microtus agrestis) and the common vole (Microtus arvalis). Compared with the previously study, a new species was identified: the yellow-necked mouse and another one was missing: the bank vole (Myodes glareolus).

Corrigendum to Winter diet of Long-eared Owls (Asio otus) in the southern Pannonian Plain (Serbia, Vojvodina)

Corrigendum to Winter diet of Long-eared Owls (Asio otus) in the southern Pannonian Plain (Serbia, Vojvodina)

Short communication: Vocalization of the Long-eared owl Asio otus (Strigiformes, Strigidae) in the Middle Volga, Russia

Abstract. Andreychev A, Lapshin A, Kuznetsov V. 2021. Short Communication: Vocalization of the Long-eared owl Asio otus (Strigiformes, Strigidae) in the Middle Volga, Russia. Biodiversitas 22: 5325-5330. Both daily and seasonal year-round vocalizations of the Long-eared owl (Asio otus) (Linnaeus, 1758) were recorded in the Middle Volga River region, Russia with the use of digital dictophones. Voice recorders were installed in the daytime for up to 5 days. The maximum duration of continuous operation of voice recorders was about 140 hours. By the time the previous recording was finished, we would arrive and move the recorder to a different location. The Long-eared owl can be classified as a moderately vocalizing bird, with calls recorded during 3 spring months. Peak activity is associated with pre-incubation and incubation periods. In the spring months, calls of the Long-eared owl were recorded from 16.37 h to 03.43 h. In the spring, the Long-eared owl began to cry before sunset (from 1 hour 30 minutes to 3 hours 15 minutes) and after sunset (from 56 minutes to 3 hours 39 minutes). Vocalization started after sunset for an average of 50 minutes. Vocalization always ended before dawn (to 1 h 21 min). Statistically significant differences in the duration of vespers and morning vocalizations were obtained with the use Mann-Whitney U test (Z = -3.08; p < 0.05).

Conservation Letter: Raptors and Anticoagulant Rodenticides

Conservation Letter: Raptors and Anticoagulant Rodenticides

First Report on Detection and Molecular Characterization of Adenoviruses in the Small Indian Mongoose (Urva auropunctata).

Using a broad-range nested PCR assay targeting the DNA-dependent DNA polymerase (pol) gene, we detected adenoviruses in 17 (20.48%) out of 83 fecal samples from small Indian mongooses (Urva auropunctata) on the Caribbean island of St. Kitts. All 17 PCR amplicons were sequenced for the partial pol gene (~300 bp, hereafter referred to as Mon sequences). Fourteen of the 17 Mon sequences shared maximum homology (98.3–99.6% and 97–98.9% nucleotide (nt) and deduced amino acid (aa) sequence identities, respectively) with that of bovine adenovirus-6 (species Bovine atadenovirus E). Mongoose-associated adenovirus Mon-39 was most closely related (absolute nt and deduced aa identities) to an atadenovirus from a tropical screech owl. Mon-66 shared maximum nt and deduced aa identities of 69% and 71.4% with those of atadenoviruses from a spur-thighed tortoise and a brown anole lizard, respectively. Phylogenetically, Mon-39 and Mon-66 clustered within clades that were predominated by atadenoviruses from reptiles, indicating a reptilian origin of these viruses. Only a single mongoose-associated adenovirus, Mon-34, was related to the genus Mastadenovirus. However, phylogenetically, Mon-34 formed an isolated branch, distinct from other mastadenoviruses. Since the fecal samples were collected from apparently healthy mongooses, we could not determine whether the mongoose-associated adenoviruses infected the host. On the other hand, the phylogenetic clustering patterns of the mongoose-associated atadenoviruses pointed more towards a dietary origin of these viruses. Although the present study was based on partial pol sequences (~90 aa), sequence identities and phylogenetic analysis suggested that Mon-34, Mon-39, and Mon-66 might represent novel adenoviruses. To our knowledge, this is the first report on the detection and molecular characterization of adenoviruses from the mongoose.

Winter diet of Long-eared Owls (Asio otus) in the southern Pannonian Plain (Serbia, Vojvodina)

Owl diets undergo qualitative changes across the different regions of their area of distribution. During the four winters (from 2014–15 to 2017–18), Long-eared Owls’ pellets were collected at three winterroosts located at the southern part of Pannonian Plain, in the Serbian province of Vojvodina. In 8070 prey items from pellets, we identified 16 mammal and 32 bird species. The Common Vole was the dominant prey species with a proportion in a range from 27.4% to 71.6%. The Muridae family formed a supplementary part of the diet: Mus sp., wood mouse and harvest mouse, during all winters. Birds were also a major supplementary prey during winter 2014–15, comprising 10.6%. A comparison of our results with the diet of Long-eared Owls wintering at the northern Pannonian plain (southwestern Slovakia) indicated an increase the proportion of some species in the southern part. How different land uses in agriculture and environmental conditions may be reflected in the food supply are discussed in relation to the diet composition of Long-eared Owls and an environment whose is richer provides both growing diversity in the diet of these owls and an expansion of their food niche. Our study described the Long-eared Owl as opportunistic predators expanding their food niche in the presence of diversified prey.

Mercury contamination in terrestrial predatory birds from Northeast China: Implications for species and feather type selection for biomonitoring

Mercury (Hg), a persistent potent neurotoxin, poses a serious hazard to human and wildlife health. Although highly elevated concentrations were documented in the environmental compartments of China, very few investigations were conducted regarding Hg bioaccumulation in terrestrial vertebrates, particularly avian species at the top trophic position. To assess to what degree the predatory raptors are subject to Hg contamination, we measured feather Hg concentrations from two diurnal raptors, two nocturnal owls, and one predatory passerine, collected from Northeast China. Results showed that the feather Hg concentrations were not greater than 3.67 mg/kg. Notably, there is a significant difference in feather Hg among species: Brown Shrike > Amur Falcon = Common Kestrel > Long-eared Owl > Little Owl. Brown Shrike had the highest feather Hg (1.27 ± 0.91 mg/kg), approximately three times higher compared to the diurnal predators (0.41 ± 0.33 mg/kg), and about seven-folds higher than the owls (0.18 ± 0.19 mg/kg). There were no differences in Hg concentrations between the tips of primary and tail feathers, but their correlations were significantly positive (between 0.45 and 0.96). Overall, the primary Hg = 0.15 + 0.74 × tail Hg (R2 = 0.61). Specifically, a great correlation between the primaries and tails in owls, while a weaker but significant correlation found in falcons/shrikes, provides insight into Hg content in feather tracts for biomonitoring. Our research is among the few studies regarding Hg contamination in the terrestrial predatory avian population in China. We discussed the influencing factors, the ecotoxicological risks to the terrestrial/marine avian population, and the limitations of this research.

Long-term dynamics of trematode infections in common birds that use farmlands as their feeding habitats

BackgroundThe biodiversity of farmland habitats is witnessing unprecedented change, mostly in declines and simplification of assemblages that were established during centuries of the use of traditional agricultural techniques. In Central Europe, conspicuous changes are evident in populations of common farmland birds, in strong contrast to forest birds in the same region. However, there is a lack of information on longitudinal changes in trematodes that are associated with common farmland birds, despite the fact that diversity of trematodes is directly linked to the preservation of long-established food webs and habitat use adaptations of their hosts.MethodsWe analyzed the population trends of trematodes for the period 1963–2020 in six bird species that use Central European farmlands as their predominant feeding habitats. Namely, we examined Falco tinnunculus, Vanellus vanellus, winter populations of Buteo buteo, Ciconia ciconia, extravilan population of Pica pica, and Asio otus, all originating from the Czech Republic.ResultsWe observed dramatic population losses of all trematode species in C. ciconia and V. vanellus; the changes were less prominent in the other examined hosts. Importantly, the declines in prevalence and intensity of infection affected all previously dominant species. These included Tylodelphys excavata and Chaunocephalus ferox in C. ciconia, Lyperosomum petiolatum in P. pica, Strigea strigis in A. otus, Neodiplostomum attenuatum and Strigea falconis in B. buteo (χ2 test P < 0.001 each), and Echinoparyphium agnatum and Uvitellina adelpha in V. vanellus (completely absent in 2011–2000). In contrast, the frequency and spectrum of isolated records of trematode species did not change to any large extent except those in V. vanellus.ConclusionsThe analysis of six unrelated common bird species that use farmlands as their feeding habitats revealed a previously unreported collapse of previously dominant trematode species. The previously dominant trematode species declined in terms of both prevalence and intensity of infection. The causes of the observed declines are unclear; of note is, however, that some of the broadly used agrochemicals, such as azole fungicides, are well known for their antihelminthic activity. Further research is needed to provide direct evidence for effects of field-realistic concentrations of azole fungicides on the survival and fitness of trematodes.Graphical abstract

The effect of environmental variables on owl distribution in Central Europe: A case study from the Czech Republic

Species distributional data from atlas projects collected by volunteers and professionals play an essential role in ecology and biodiversity conservation. Atlas data primarily allow evaluating longitudinal and latitudinal gradients in species distribution. However, the effects of additional factors such as elevation and associated climatic conditions and landscape structure are rarely assessed. We used the original data from the Atlas of birds breeding in the Czech Republic in terms of the presence and absence (0/1) of breeding occurrence of seven owl species in 604 mapping quadrates (each quadrate 12.0 × 11.1 km in size) to assess the effect of elevation (reaching from 100 to 1100 m a.s.l.) and temperature on the distributional patterns of the owls. Using a multivariate spatial analysis with latitude and longitude as space predictors and landscape structure as covariates, we found that elevation and temperature significantly affected owl distribution; the model explained 94.8% of the variability (p = 0.002). Only the boreal owl (Aegolius funereus) showed a clear preference for the highest elevation, and simultaneously, boreal and pygmy (Glaucidium passerinum) owls preferred the coldest environments. Eagle owl (Bubo bubo) and tawny owl (Strix aluco) most often occupied low and middle elevation of moderate temperatures. Barn owl (Tyto alba) and long-eared owl (Asio otus) inhabited the warmest areas in low elevations. Finally, little owl (Athene noctua) most often occurred in the lowest elevations of intermediate temperatures. We have documented that the elevation and associated climate conditions can work as an effective predictor to assess distributional preferences of owl species based on atlas data. The findings can be helpful when the management of owls' habitats is considered and implemented. For example, the results of our case study suggest that the boreal owl can be susceptible to global warming and intensive logging at high elevations.

A new extinct species of Margarobyas (Strigiformes) and the evolutionary history of the endemic Cuban bare-legged owl (M. lawrencii)

ABSTRACT The Cuban bare-legged owl (Margarobyas lawrencii) is a poorly studied bird of uncertain affinities within Strigidae (true owls). Molecular data indicate that M. lawrencii may be one of the earliest diverging lineages of crown group Strigidae, but the evolutionary history of this taxon remains obscure. Here we describe a fossil species of Margarobyas from the Upper Pleistocene of Western Cuba and for the first time address the comparative osteology of this genus. The osteological survey confirms the remarkable morphological distinctiveness of the modern Margarobyas lawrencii. Margarobyas displays a derived similarity to Ninox owls (hawk-owls, subfamily Ieraglaucinae) in the morphology of the quadratum, but in the overall morphology of the skeleton it is also similar to members of the subfamily Striginae and species of Megascops (screech owls) in particular. The mixture of characters of both Striginae and Ieraglaucinae implies an early (no later than Oligocene) divergence of Margarobyas, thus supporting a long evolutionary history of these owls compared with other endemic owl species of the West Indies. The antiquity of Margarobyas makes it, along with Todidae (todies), one of the most archaic components of the modern West Indian avifauna.