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Understanding the foraging ecology of the rapidly declining little owl (Athene noctua), which faces food limitations during the breeding season, is crucial for its effective conservation and management. We assessed the composition of prey provisioned to nestlings using nestbox cameras from 2002-2022 in three countries with different landscape structures (the Czech Republic, Slovakia and the Netherlands). We particularly explored the effect of region (country), nesting stage and parental sex on prey composition. From 41,342 identified prey items, insects predominated the little owl's diet (75.6%), followed by earthworms (19%) and a smaller proportion of vertebrates (mammals and birds). The highest proportion of insects was found in the Netherlands (80.9%), whereas earthworms dominated in Slovakia (79.8%). Vertebrates (particularly small mammals) were important prey delivered during the incubation and early nesting stages, and the representation of insects increased with the progression of the breeding season. Representation of earthworms was highest in the late nesting stage. Females provisioned a higher percentage of earthworms, whereas males provisioned more vertebrates. In conclusion, the little owl's diet during the breeding season comprises a surprisingly high proportion of invertebrates. Further, differences in prey provided are most likely driven by climatic factors, habitat structure and land-use histories (causing differences between countries), different energy requirements and seasonal changes in prey availability (causing differences during individual nesting stages) and sex-specific foraging strategies and parental roles (causing differences between sexes). Conservation activities should focus on restoration and suitable management of different high-quality habitats to enhance the availability and representation of different prey taxa within little owls' territories. [ABSTRACT FROM AUTHOR]

Little Owl (Athene noctua Scop., 1769) is common and widespread throughout Bulgaria, inhabiting various habitats, including farmland, orchards, villages, and urban areas. In recent years, its population has declined in almost all of Europe. The present study revealed an average Little Owl population density of about 0.05 breeding pairs / km² in Bulgaria. Its density varies depending on the region. The species is more abundant in the lowlands of northern Bulgaria, where the density can reach up to 0.07 breeding pairs / km², while in the mountains, the density is lower, with only 0.03 breeding pairs / km² in some areas. The Little Owl population in Bulgaria declined between 2007 and 2016 by 30 %. The main factor in Bulgaria for the decrease in numbers is the construction of new buildings or the renovation of old ones. Among the factors negatively influencing the species' population are habitat loss and fragmentation, changes in agricultural practices, and changes in prey availability. The places where they nest or roost depend on human presence. In particular, converting traditional farmland to intensive monoculture has been identified as a potential threat to the Little Owl population in some regions of Bulgaria. [ABSTRACT FROM AUTHOR]

AbstractKnowing people are willing to protect wildlife when they feel connected with nature, we used owls as a case study to review owl symbolism in Greek history (2900 BC − 2000 AD). For five millennia, Greek civilization thrived and used owls as a dominant symbol in major cultural expressions. Consequently, a broad spectrum of social beliefs evolved towards owls. Until 1500 BC, they were mainly used as decorative attributes. During the Mycenaean era, though, owls began to be worshipped as eerie creatures in funeral rituals, inducing fear and respect. When Greek civilization peaked during the Archaic, Classical and Hellenistic periods, an important shift is noticed in social perceptions. Owls are transformed into major symbols of wisdom, power, justice and divinity, connected to the goddess Athena and the city of Athens. Their significance faded in the subsequent Roman period and was absent throughout the Byzantine era, for 1500 years. When owls reappeared after 1800 AD in cultural aspects of modern Greece, society again considered them fearsome creatures. We finalize our historical review with a recent survey in Greece, capturing up-to-date trends. Our survey indicates that today: (i) owls are mostly considered beneficial and deserving of protection, but part of the population still perceives owls as bad omens, powerful and scary; (ii) elementary concepts of raptors’ importance in ecosystems are still unknown to many; (iii) a small but impactful percentage still deliberately kill house-nesting owls, outlining the need to educate and provide nest-boxes as a relocation solution. By performing a thorough review of historical perceptions toward owls, important insights are offered on how to positively connect people with their wildlife and cultural heritage. We claim that people who understand how nature was related to their country in the past are inspired and more inclined to protect it.

This study gives a comprehensive description of eyelids movement in little owl and discusses the impact of some surrounding conditions in their kinetic performance. The present study used the video's recording technique to record the kinetic activity of eyelids, besides the anatomical and histological studies of the eyelid's structure. The fundamental eyelid movements can be uniquely and reliably characterized by their anatomical relationship that was confirmed via video recording for their kinetic activity. The levator palpebrae muscle is considered a main generating motor for the upper eyelid; in the little owl, this muscle splits into multiple directions and is distinguished from the levator palpebrae superioris (Lps) and the levator anguli oculi (Lao) muscle. That anatomical pattern of insertion increases the movement of the upper lid. On the other side, the contraction of depressor palpebrae inferioris (Dpi) muscle and the active upward forces of levator palpebrae muscle help in increasing the opening of the eye's fissure. However, the closure process is produced from the passive downward forces and relaxation of the levator palpebrae superioris (Lps), levator anguli oculi (Lao), and depressor palpebrae inferioris muscle, as well as the contraction of retractor anguli oculi lateralis (Raol) and medialis (Raom) muscle. The present results also recorded that nictitating membrane's (Nm) movement is reversely proportionate to the level of kinetic of other eyelids. The mobility of Nm in little owl occurs under the effect of artificial external stress. These anatomical data and sequence video recordings have confirmed that the upper eyelid moves more compared to other eyelids. The authors also suggest that the mobility of eyelids may get stimulated through external pressure force of some surrounding structure like the periorbital sheet. Also, the histological study exhibited that the structure of two eyelids is very similar in the little owl and the variability is showing in the number of cell layers that forms their epithelium of skin and palpebral surfaces, the distribution of pigment granules, and degree of keratinization on their surface. That variability in the histological characters of eyelids may counteract the abrasive forces occurring during the opening and closing processes. [ABSTRACT FROM AUTHOR]

Knowing people are willing to protect wildlife when they feel connected with nature, we used owls as a case study to review owl symbolism in Greek history (2900 BC - 2000 AD). For five millennia, Greek civilization thrived and used owls as a dominant symbol in major cultural expressions. Consequently, a broad spectrum of social beliefs evolved towards owls. Until 1500 BC, they were mainly used as decorative attributes. During the Mycenaean era, though, owls began to be worshipped as eerie creatures in funeral rituals, inducing fear and respect. When Greek civilization peaked during the Archaic, Classical and Hellenistic periods, an important shift is noticed in social perceptions. Owls are transformed into major symbols of wisdom, power, justice and divinity, connected to the goddess Athena and the city of Athens. Their significance faded in the subsequent Roman period and was absent throughout the Byzantine era, for 1500 years. When owls reappeared after 1800 AD in cultural aspects of modern Greece, society again considered them fearsome creatures. We finalize our historical review with a recent survey in Greece, capturing up-to-date trends. Our survey indicates that today: (i) owls are mostly considered beneficial and deserving of protection, but part of the population still perceives owls as bad omens, powerful and scary; (ii) elementary concepts of raptors' importance in ecosystems are still unknown to many; (iii) a small but impactful percentage still deliberately kill house-nesting owls, outlining the need to educate and provide nest-boxes as a relocation solution. By performing a thorough review of historical perceptions toward owls, important insights are offered on how to positively connect people with their wildlife and cultural heritage. We claim that people who understand how nature was related to their country in the past are inspired and more inclined to protect it. [ABSTRACT FROM AUTHOR]

The Little Owl is a species with a wide range in the Palearctic. Thirteen subspecies have been described based on small coloration or size differences. Recently, genetic studies in the western portion of the European range have shown the presence of some well distinct clades. We examined the variation in structural size and coloration of Western Palearctic birds, with particular attention to the pattern of light and dark pigmentation on the tail, and we checked for the presence of UV reflection through reflectance spectroscopy. We did not find clear-cut differences in size or plumage between the currently accepted subspecies, nor between individuals pertaining to the different genetic clade areas. There is a trend for individuals from the western genetic clade (Iberia, France, England and central Europe) to have longer tarsus with smaller wings, while individuals from the eastern generic clade (Balkans) have an opposite pattern. Italian birds are intermediate. The tail of Balkan birds has a wider dark pigmentation, with reduced light spots. Little owl feathers do not show reflectance in the UV part of the spectrum. We found a very large variation of morphological and color patterns between individuals collected in the same geographical area. Currently, the arrangement of individuals to any Little owls' subspecies on morphological data appears to be a very difficult task. [ABSTRACT FROM AUTHOR]

Birds show huge variation in color displays evolved for communication. However, among colored phenotypic traits, eyes remain largely overlooked, with only a few studies suggesting a potential signaling function or a role in mate recognition and crypsis. Iris color is a remarkably striking feature in the wholly cryptic pattern of many owls, and may potentially play a signaling function, a possibility so far neglected. Here, we studied variation and potential signaling of iris yellowness as an indicator of quality in parent-offspring communication and other social contexts in the Little Owl (Athene noctua) and Eurasian Scops-Owl (Otus scops). Yellowness did not differ between the sexes; however, adults of the two species had more intensely yellow irises than owlets. Most of variation in iris yellowness of owlets occurred between rather than within nests and seemed to be linked to parental qualities of Little Owls, but was unrelated to condition among Eurasian Scops-Owl owlets. In adults, however, we found that iris yellowness of females was positively associated with nest success (an index of female fitness) in Little Owls, but not in Eurasian Scops-Owls. This study suggests that iris color variation is unlikely to play a role in parent-offspring communication for these two owl species, but that iris yellowness of female Little Owls may potentially play a signaling role in social contexts, a possibility that should be studied in the future. [ABSTRACT FROM AUTHOR]

Social information use has well-known fitness benefits. However, causes underlying the apparent inter-individual variability in the propensity to use social information are poorly studied. Melanins are pigments responsible for most of intra-specific color variation in vertebrates and their variation is often associated with changes in behaviour. Here, we explored whether melanism is related to individual propensity to use social information in the color polymorphic scops owl Otus scops. We manipulated social information on predation risk at nests by broadcasting calls of the sympatric little owl Athene noctua and found that owlets of brownish females exposed to alarm calls had lower levels of natural antibodies than those of greyish females. In parallel, we found changes in parental behaviour contingent on coloration because when exposed to the risky treatment brownish females returned earlier to nests than greyish females and owlets raised by brownish females were fed with smaller prey than those raised by greyish ones. These results provide support for a previous ignored role of melanins on the propensity to use social information, which may help to explain the maintenance of melanin-based color polymorphisms wherever social environments are variable. [ABSTRACT FROM AUTHOR]

Equivocal knowledge of the phase-specific drivers of natal dispersal remains a major deficit in understanding causes and consequences of dispersal and thus, spatial dynamics within and between populations. We performed a field experiment combining partial cross-fostering of nestlings and nestling food supplementation in little owls (Athene noctua). This approach disentangled the effect of nestling origin from the effect of the rearing environment on dispersal behaviour, while simultaneously investigating the effect of food availability in the rearing environment. We radio-tracked fledglings to quantify the timing of pre-emigration forays and emigration, foray and transfer duration, and the dispersal distances. Dispersal characteristics of the pre-emigration phase were affected by the rearing environment rather than by the origin of nestlings. In food-poor habitats, supplemented individuals emigrated later than unsupplemented individuals. By contrast, transfer duration and distance were influenced by the birds' origin rather than by their rearing environment. We found no correlation between timing of emigration and transfer duration or distance. We conclude that food supply to the nestlings and other characteristics of the rearing environment modulate the timing of emigration, while innate traits associated with the nestling origin affect the transfer phases after emigration. The dispersal behaviours of juveniles prior and after emigration, therefore, were related to different determinants, and are suggested to form different life-history traits. [ABSTRACT FROM AUTHOR]

Aim: The nested pattern in the geographical distribution of three Indian owlets, resulting in a gradient of endemicity, is hypothesized to be an impact of historical climate change. In current time, the Forest Owlet Athene blewitti is endemic to central India, and its range is encompassed within the ranges of the Jungle Owlet Glaucidium radiatum (distributed through South Asia) and Spotted Owlet Athene brama (distributed through Iran, South and Southeast Asia). Another phylogenetically close species, Little Owl Athene noctua, which is largely Palearctic in distribution, is hypothesized to have undergone severe range reduction during the Last Glacial Maximum, showing a postglacial expansion. The present study tests hypotheses on the possible role of Quaternary climatic fluctuations in shaping geographical ranges of owlets. Methods: We used primary field observations, open access data, and climatic niche modeling to construct climatic niches of four owlets for four periods, the Last Interglacial (~120–140 Ka), Last Glacial Maximum (~22 Ka), Mid‐Holocene (~6 Ka), and Current (1960–1990). We performed climatic niche extent, breadth, and overlap analyses and tested if climatically suitable areas for owlets are nested in a relatively stable climate. Results: Climatically suitable areas for all owlets examined underwent cycles of expansion and reduction or a gradual expansion or reduction since the Last Interglacial. The Indian owlets show significant climatic niche overlap in the current period. Climatically suitable areas for Little Owl shifted southwards during the Last Glacial Maximum and expanded northwards in the postglaciation period. For each owlet, the modeled climatic niches were nested in climatically stable areas. Main Conclusions: The study highlights the impact of Quaternary climate change in shaping the present distribution of owlets. This is relevant to the current scenario of climate change and global warming and can help inform conservation strategies, especially for the extremely range‐restricted Forest Owlet. [ABSTRACT FROM AUTHOR]

Highlights • Little owls pass an embryonic phase of ear asymmetry but are symmetrical as adults. • The left ear opening is bigger than its counterpart on the right. • The ear asymmetry appears in the same developmental stages as in the barn owl. • The ear asymmetry vanishes shortly before hatching. • Our data may shine light on the evolution of the little owl. Abstract Owls are well adapted to nocturnal hunting. This includes vision tuned to low level light conditions, silent flight, and asymmetrical ears. Asymmetrical ears facilitate sound localization and evolved up to seven times independently in the evolutionary history of owls. However, there are also owl species with a crepuscular or diurnal lifestyle, like the little owl (Athene noctua), that have symmetrical ears as adults. Here we show that a small, but significant ear asymmetry occurs in the embryonic development of little owls, despite the presence of symmetrical ears in adults. In the asymmetric period, the left ear opening is bigger in area than its counterpart on the right. The asymmetry in the little owl occurs in the same stages at which the asymmetry in the barn owl (Tyto furcata) develops, but in the little owl the asymmetry vanishes shortly before hatching. Asymmetries in the size of the ear openings are also found in the adults of other owl species, most of them belonging to the genus Strix. We interpret our finding as an indication of a secondarily evolved diurnal activity in little owls. Further, ear asymmetry might be more deeply rooted in the evolution of owls than previously assumed. [ABSTRACT FROM AUTHOR]

Nest box supplementation is widely used to increase nest‐site availability for cavity nesting animals but the analysis of its effects on individuals breeding in natural cavities is often neglected. This study offers a novel restoration technique to revert abandonment of natural breeding sites by a secondary cavity avian bird, the European roller (Coracias garrulus), and other ecologically similar species. We found that, after a program of nest box supplementation with ensuing monitoring, rollers gradually abandon nesting in natural and seminatural cavities in favor of nest boxes because the latter are of higher quality. We examine whether reducing the entrance size of natural and seminatural cavities improves their suitability for rollers. A 6‐year program reduced the diameter of the entrance of sandstone cavities and cavities in bridges. This led to a high occupancy (59%) of manipulated nest‐sites. Manipulated sites were most frequently occupied by rollers and little owls (Athene noctua) (31 and 18% of sites, respectively). Manipulation did not affect clutch size or fledgling success. We suggest that nest‐site diversity and nesting in natural cavities should be preserved to reduce nest box dependence. Our study illustrates the value of nest boxes when used alongside restoration of natural breeding sites and provides insights for the management of natural cavities. [ABSTRACT FROM AUTHOR]

Between 29 Mar and 10 Apr, 2015, a Little Owl Athene noctua survey was carried out using the playback method in the southern part of Montenegro. The study area was situated between the town of Ulcinj and the Bojana River delta. A total of 55 calling males were registered at 26 survey points with a maximum of 4 calling males per survey point. Considering the low response rate of the Little Owl, its local population was estimated at be 55–110 calling males. This study presents the first systematic survey of the Little Owl in Montenegro. [ABSTRACT FROM AUTHOR]

Abstract Habitat models are fundamental tools for designing evidence-based conservation measures, particularly for locating sites with high potential for promoting a species' recolonisation and occupancy. However, it remains challenging to respond to both the need for large-scale general rules, and for fine-scale information concurrently. Multi-level habitat models provide all-in-one surfaces that explicitly account for conditional dependencies among single-level selection probabilities. We integrated occurrence data obtained from citizen-science species observation data with radio-tracking data to develop multi-level resource selection functions for the little owl (Athene noctua), a species of conservation concern in Central Europe. The results of our habitat selection analyses confirmed that suitable little owl habitat is located in widely open agricultural landscapes that often exist in the vicinity of human settlements. We mapped habitats at fine resolution (40 × 40 m) over an area covering 77,313 km2 in Switzerland and Baden-Württemberg, Germany. We validated the models with external out-of-sample data, and we demonstrated good predictive ability and transferability over the broad landscape. Overall, a fifth of the modelled landscape was estimated to be suitable for little owls. Habitat suitability scores in Switzerland were generally lower than in Baden-Württemberg due to higher elevation, fewer orchards, and more forest patches. Extant populations currently occupy c. 15% of the potential suitable habitats in Baden-Württemberg, and 2% in Switzerland, suggesting that considerable space for recolonisation is available. However, while Baden-Württemberg offers vast open landscapes, lowlands in Switzerland show narrow swaths of habitat along valleys and lakes. We showed that the simultaneous integration of different levels of habitat selection behaviour into a multi-level habitat suitability map creates a promising tool for conservation planning of endangered species over large geographical areas. Our multi-level model allowed for identification of both large-scale habitat suitability patterns to develop conservation strategies, and fine-scale clusters of high quality habitats where conservation measures can be applied at once, thereby increasing relevance of such all-in-one habitat maps for policy makers, wildlife managers and conservations practitioners alike. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the rules of habitat selection and the individual behavioural routines in the home‐range is crucial for developing evidence‐based conservation action. We investigated habitat selection and range use of adult little owls Athene noctua in relation to landscape configuration, habitat structure and resource distribution. We determined the preference of habitat structures by VHF‐telemetry. Large‐ and fine‐scale distribution patterns of voles – the main prey during the breeding season – were assessed by transect counts of signs of vole presence. An experiment using artificial perches was carried out to determine the fine‐scale adjustment of the owls' range use in relation to prey abundance and vegetation height. Habitat selection and resource exploitation by little owls were structured at all spatial levels: (1) at the landscape scale, orchards were highly preferred over other areas. This accords with the patchy large‐scale occurrence of voles, which were absent in cropland, but abundant in orchards and grassland; (2) within home‐ranges, the spatial distribution of voles was highly inhomogeneous and structures with high prey abundance were used over‐proportionally; (3) at the scale of foraging sites, little owls preferred patches with low vegetation over those with high prey abundance, establishing that prey availability is the crux. The results suggest that all levels of habitat selection and range use were related to farming practices and affected by current cultivation. Conservation measures should focus on the conservation and restoration of orchards on the landscape level and habitat management measures should focus on grasslands – the main food providers – by creating a mosaic of patches with short grass and tall grass. Together with other habitat structures providing food resources such as field edges, wildflower areas and structures facilitating access to prey, the quality of habitat patches in terms of food availability may be highly improved. [ABSTRACT FROM AUTHOR]

The Little Owl is currently endangered bird species of agricultural lowland areas in Central Europe. Nesting sites of the Little Owl are often old trees as well as buildings and quarries with suitable nesting cavities. The Little Owl has severely declined in a major part of Europe during the past decades. Information on habitat requirements of the Little Owl and data related to land-use changes at nest sites (covering both the breeding and foraging habitats) are needed for conservation programmes aimed at this bird species. Land-use changes in farmland rank among frequently discussed negative factors causing the population decline of the Little Owl. The aim of this study is to analyse land-use changes at nest sites of the Little Owl in the South-Moravian region (Czech Republic) between the years 1976/1977 and 2014. In both studied periods (1976/1977 and 2014), the most important land-use type within 500 m from the nest sites of the Little Owl was arable land (66.94 % - 62.25 %), followed by built-up areas (19.97 % -22.41 %), while the other land-use types made up less than 5 %. The proportion of the particular land-use type did not change significantly between the years 1976/1977 and 2014. The most important change in comparison with the period 1976/1977 was the decrease in the area of arable land by 4.69 % and that of orchards and gardens by 1.99 %, while the surface of built-up areas increased slightly by 2.45 % and that of meadows and pastures by 1.5 %. The analysis shows that at the known nest sites of the Little Owl in the South-Moravian region (Czech Republic), there were no significant changes in the proportion of the particular land-use types within 500 m from the nests between the years 1976/1977 and 2014. Based on these results, we can conclude that in comparison with the availability of nest sites, which seems to be the important limiting factor for the occurrence and population density of the Little Owl, land-use changes in study area were not very important factor influencing decline of the Little Owl. [ABSTRACT FROM AUTHOR]

The agricultural scene has changed over the past decades, resulting in a declining population trend in many species. It is therefore important to determine the factors that the individual species depend on in order to understand their decline. The landscape changes have also resulted in habitat fragmentation, turning once continuous populations into metapopulations. It is thus increasingly important to estimate both the number of individuals it takes to create a genetically viable population and the population trend. Here, population viability analysis and habitat suitability modeling were used to estimate population viability and future prospects across Europe of the Little Owl Athene noctua, a widespread species associated with agricultural landscapes. The results show a high risk of population declines over the coming 100 years, especially toward the north of Europe, whereas populations toward the southeastern part of Europe have a greater probability of persistence. In order to be considered genetically viable, individual populations must count 1,000-30,000 individuals. As Little Owl populations of several countries count <30,000, and many isolated populations in northern Europe count <1,000 individuals, management actions resulting in exchange of individuals between populations or even countries are probably necessary to prevent losing <1% genetic diversity over a 100-year period. At a continental scale, a habitat suitability analysis suggested Little Owl to be affected positively by increasing temperatures and urban areas, whereas an increased tree cover, an increasing annual rainfall, grassland, and sparsely vegetated areas affect the presence of the owl negatively. However, the low predictive power of the habitat suitability model suggests that habitat suitability might be better explained at a smaller scale. [ABSTRACT FROM AUTHOR]

The feeding of Little Owl (Athene noctua) was studied in a farmland area of Kiskunság, Central Hungary. For the analyses, a total of 661 Little Owl pellets were collected between February and September 2005 from three locations, corresponding known Little Owl territories situated nearby the settlements Apaj, Kunpeszér and Ladánybene. The aim of the present study was to explore the diet composition of Little Owl and to give a detailed evaluation of the arthropod diversity based on the pellet analysis. The identified prey items represented 15 vertebrate and 39 invertebrate species/taxa. In terms of prey number, dominance of small mammals was observed in two sites (Apaj - 55%, Kunpeszér - 68%), while birds and mammals shared almost equal dominance (~25%) in Ladánybene. The most numerous mammal species was the Common Vole (Microtus arvalis), while the Starling (Sturnus vulgaris) played key role among the birds. Contribution of amphibian Common Spadefoot (Pelobates fuscus) was considerable, while share of reptiles was marginal. Vertebrates also played a predominant role by contributing over 99% of the overall prey biomass in all study sites. Invertebrate prey dominance ranged from 24.8-30.0% while their contribution to the overall biomass was very low (0.14-0.34%). Large sized beetles (Pentodon idiota, Melolontha hippocastani) and orthopterans (Tettigonia viridissima, Gryllotalpa gryllotalpa) were preferred. Arthropod species richness and diversity were the highest in Kunpeszér, supposedly owing to the rich mosaic habitat structure. [ABSTRACT FROM AUTHOR]

Between 1995 and 2017 we carried out surveys on the Little Owl (Athene noctua) in Battonya town and Kevermes village in southern Békés county. In 2007 and 2017 we have surveyed nesting sites in the village and the outer areas of Kevermes. The population of the species was estimated at the beginning of the breeding season and in early summer with field observations. Between 1995 and 2017 we collected road-kill data within the entire administrative area of Battonya. We registered each fiund road-killed Little Owl. We found 64 road-kills in Battonya. The number of casualties of the species has increased unambiguously over the studied 23 years. Most of the road-killed Little Owls (53 individuals, 82.81% of the total) were found in summer (June-August). 51 roadkilled individuals (79.69%) were noted in the outer areas of Battonya, and 13 specimens (20.31%) in the town. Our results highlight that vehicle traffic is an important mortality factor for the population. The Little Owl has a large population in this landscape, and the population size has increased over the last decade. In the background of this increase is most likely the rise in the number of abandoned houses because of the unfavourable economic and social situation in the region. The local pairs nested only on attics and roof structures in Kevermes, often in residential buildings. The buildings of modern agriculture do not meet the needs of the species. A large part of the population breeds in the village, because with the disappearance of the farms the breeding pairs of the outer areas of Kevermes have disappeared. However, in Battonya the species regularly breeds in the outer areas of the town. Finally, we also collected some ethnoecological data on how local people relate to the species. [ABSTRACT FROM AUTHOR]

This study focused on the clutch size and age-specific apparent survival rate of the Little Owl (Athene noctua) population in Upper-Kiskunság, Hungary. Between May 2005 and April 2017, 640 individuals were captured and ringed in a total of 746 capture-recapture occasions. Artificial nest boxes were installed in the study area, breeding birds and pulli were captured for ringing/recaptured in these boxes (from March to May), or at the close neighbourhood of those (max. 168 m). Jolly-Seber's open population method was applied to model the survival rate. The candidate model set included models incorporating age, year-effect, and the combination of those. AICc value was used to compare models in a selection approach. The final model was constructed via model averaging based on the models with significant explanatory power. The average number and SD of pullus/breeding pair was 3.78 ± 0.76. The average apparent annual survival rate (which does not differentiate between mortality and permanent emigration) for the period between pullus stage and the time of the first breeding was estimated as 9.47% ± 2.99% SE, whereas the annual survival rate of adults was 82.74% ± 8.46% SE. The effect of sex on the survival rate of adults was not investigated due to female-biased sample, as the probability of capturing females is significantly higher in late spring months. Our experience reveals that during February and March it is possible to capture both sexes in the nest boxes, and it does not influence negatively the breeding success. Based on our results, the population of the Little Owl is stable in Upper-Kiskunság. A slight increase in estimated population size is observable even if we make no difference between mortality and permanent emigration. The high occupancy rate of the installed nest boxes reveals that nest site availability is an important limiting factor in the studied population. [ABSTRACT FROM AUTHOR]

Kitowski I., Stasiak K. The disappearance of barn owl Tyto alba and little owl Athene noctua occurrence sites in farmland in East Poland. Ekologia (Bratislava), Vol. 32, No. 4, p. 361-368, 2013.

Long-term population decline of the little owl has been recorded in Western Europe and available evidence also suggests severe range restriction in many Central European regions. Using two nationwide volunteer-based monitoring programmes during the years 2009-2016, we investigated distribution, population density and breeding associations of the little owl in the Czech Republic and Slovakia. Across the two countries combined, the average population density of the little owl was 0.19 calling males/10 km². However, the population density was markedly higher in Slovakia (0.36 calling males/10 km²) than in the Czech Republic (0.09 calling males/10 km²). The overall breeding population of the little owl was estimated at 130 breeding pairs in the Czech Republic and 550 in Slovakia. Compared to the situation two decades ago, those estimates represented a 87-94 % decline in the breeding population in the Czech Republic and a 31-45 % reduction in Slovakia. Our data also revealed marked distributional range contraction of the little owl, indicating rapid local extinctions over the last two decades. The analysis of expected breeding places of the little owl confirmed a strong preference for man-made objects over the original breeding sites in tree cavities. In the light of our present results, we propose urgent preparation and implementation of a species action plan with conservation measures to halt the little owl's steep decline in Central Europe. [ABSTRACT FROM AUTHOR]

Among the range of determinants of post-fledging survival in altricial birds, the energy supply to the growing juveniles is likely to play a central role. However, the exact mechanisms shaping post-fledging survival are poorly understood. Using a food supplementation experiment, we determined the effect of variation in food supply on the survival of juvenile Little Owls Athene noctua from hatching to 2 months post-fledging. Experimental broods were food-supplemented for 36 days during the nestling and the early post-fledging period. The fate of 307 juveniles (95 of them provided with extra food) was determined by nest monitoring and radiotelemetry. In unsupplemented birds, the rates of survival measured at 5-day intervals were lowest during the nestling stage, remained low during the early post-fledging stage and steadily increased after about 2 weeks post-fledging. Food supplementation substantially increased nestling survival, but we detected no direct treatment effect on post-fledging survival. Instead, we found a strong indirect effect of food supplementation, in that fledglings of good physical condition had markedly higher chances of surviving the post-fledging period compared with those in poor condition. Experimental food supplementation increased survival over the first 3 months from 45% to 64.6%. This suggests that energy reserves built up during the nestling stage influence post-fledging survival and ultimately parental reproductive output. The low nestling and post-fledging survival shows that the early life-history stages constitute a crucial bottleneck of reproductive ecology in Little Owls. The strong treatment effects on the number of independent offspring indicate that natural variation in food supply is an important determinant of spatio-temporal patterns in Little Owl demography. [ABSTRACT FROM AUTHOR]

In many bird species, parents adjust their home-ranges during chick-rearing to the availability and distribution of food resources, balancing the benefits of energy intake against the costs of travelling. Over recent decades, European agricultural landscapes have changed radically, resulting in the degradation of habitats and reductions in food resources for farmland birds. Lower foraging success and longer foraging trip distances that result from these changes are often assumed to reduce the reproductive performance of parents, although the mechanisms are not well understood. We tested the behavioural response of chick-rearing Little Owls Athene noctua to variation in habitat diversity in an agricultural landscape. We equipped females with GPS loggers and received adequate range-use data for 19 individuals (6063-14 439 locations per bird). In habitats dominated by homogeneous cropland habitats, home-ranges were over 12 ha in size, whereas in highly diverse habitats they were below 2 ha. Large home-ranges were associated with increased flight activity (117% of that of birds in small home-ranges) and distances travelled per night (152%), increased duration of foraging trips (169%) covering larger distances (246%), and reduced nest visiting rates (81%). The study therefore provides strong correlative evidence that Little Owls breeding in monotonous farmland habitats expend more time and energy for a lower benefit in terms of feeding rates than do birds in more heterogeneous landscapes. As nestling food supply is the main determinant of chick survival, these results suggest a strong impact of farmland characteristics on local demographic rates. We suggest that preserving and creating islands of high habitat diversity within uniform open agricultural landscapes should be a key target in the conservation of Little Owl populations. [ABSTRACT FROM AUTHOR]

To combat the threat of predation, prey species have developed a variety of ways to recognize and respond appropriately to novel predators. While there is evidence that predator recognition does not require learning in certain species, learning appears to play an important role for other species. In systems where learning is important, it is less clear whether predator identification requires prior experience with specific predators or, whether general experience with predators provides sufficient tools for identifying similar species of novel predators. Here we test whether wild-living adult birds recognize a dangerous predator that occurs in only part of their geographical range. We presented taxidermy mounts of little owls, Athene noctua , and sparrowhawks, Accipiter nisus , to blue tits, Cyanistes caeruleus , and great tits, Parus major . All populations of both tit species co-occur with sparrowhawks, but populations differ in their prior experience with little owls. We found that tits that overlap geographically with little owls responded to little owls using the same intensity of mobbing behaviour exhibited toward sparrowhawks. In populations with no historical contact with little owls, however, both blue and great tits treated little owls as a lower threat than sparrowhawks. These results suggest that blue tits and great tits do not generalize ‘predatory features’ to novel predators and instead need prior experience with specific predators before they assign the correct level of threat. [ABSTRACT FROM AUTHOR]

The amount of high-quality habitat patches, their distribution, and the resource accessibility therein play a key role in regulating habitat effects on reproductive success. Heterogeneous habitats offer non-substitutable resources (e.g. nest sites and food) and substitutable resources (e.g. different types of food) in close proximity, thereby facilitating landscape complementation and supplementation. However, it remains poorly understood how spatial resource separation in homogeneous agricultural landscapes affects reproductive success. To fill this gap, we investigated the relationships between farmland heterogeneity and little owl ( Athene noctua) reproductive success, including potential indirect effects of the heterogeneity-dependent home-range size on reproduction. Little owl home-ranges were related to field heterogeneity in summer and to structural heterogeneity in winter. Clutch size was correlated with the amount of food-rich habitat close to the nest irrespective of female home-range size, suggesting importance of landscape complementation. Nestling survival was positively correlated with male home-range size, suggesting importance of landscape supplementation. At the same time, fledgling condition was negatively correlated with male home-range size. We conclude that decreasing farmland heterogeneity constrains population productivity by two processes: increasing separation of food resources from nest or roost sites results in low landscape complementation, and reduction of alternative food resources limits landscape supplementation. Our results suggest that structural heterogeneity affects landscape complementation, whereas the heterogeneity and management of farmland fields affect landscape supplementation. Thus, to what extent a reduction of the heterogeneity within agricultural landscapes results in species-specific habitat degradation depends on the ecological processes (i.e. landscape complementation or supplementation) which are affected. [ABSTRACT FROM AUTHOR]

The diet composition of Little Owl Athene noctua was investigated in Al Reem biosphere reserve, northern Qatar. Eighty-seven regurgitated pellets yielded 193 individual prey items representing at least five rodent spp, two lizard spp, unidentified bird(s) spp, at least one scorpion sp, several beetle (Coleoptera) and grasshopper (Orthoptera) spp. Prey items were dominated by beetles (45%) and rodents (37%) which were found in 58.6% and 70% of the pellets, respectively. Reptiles, birds, scorpions, and grasshoppers constituted 6.4, 3.8, 2.1, and 5.4% of the diet, respectively. The results suggest that the Little Owl is an opportunistic feeder, hunting 1-5 prey items per day (ave 2.03±0.13) from a wide range of fast-moving prey to ground-dwelling insects. The analysis resulted in the first record of Pygmy Gerbil Gerbillus henleyi (Rodentia) from Qatar. [ABSTRACT FROM AUTHOR]

Abstract Interactions between top predators and mesopredators of the same guild often result in habitat segregation restricting interactions to shared habitat edges. Although negative edge effects are recognized as important spatial patterns in the ecology of fragmented landscapes, the underlying mechanisms of predator–prey interactions resulting in negative edge effects remain unknown. To disentangle top‐down effects of intraguild predators and bottom‐up effects of shared resources on mesopredator spatial distribution, we recorded the occurrence of tawny owls Strix aluco in forests and their prey, the little owl Athene noctua in adjacent open areas over 2 yr across 687 km2 in Southern Germany. We developed a new, asymmetrical dynamic two‐species occupancy model investigating spatial interactions while accounting for imperfect detection. Little owl occupancy was strongly reduced within 150 m of forests, but only in the presence of tawny owls. Analysis of over 30 000 telemetry locations of 275 little owls showed that little owls strongly avoided areas closer than 150 m from the forest during range use. These results suggest that the negative edge effect is due to forest edge avoidance rather than direct predation. Potential confounding mechanisms such as food depletion or habitat avoidance at forest edges can be ruled out. Thus, top‐down effects caused by avoidance of intraguild top predators shape the spatial distribution of mesopredators such as the little owl. While habitat complexity mitigates multitrophic interactions within habitats, it is expected to reinforce multitrophic interactions between habitats, potentially leading to the suppression of mesopredators from suitable habitats.

This retrospective study analyzes the causes of morbidity of little owl (Athene noctua) admitted to the Wildlife Rehabilitation Centre of Torreferrussa from 1995 to 2010. A total of 1,427 little owls were included in the study, with an average of 89 cases per year (range: 73–116). As regards the sex category, 80.7% animals (1,152/1,427) were classified as undetermined gender, 9.1% (130/1,427) were sexed as females and 10.2% (145/1,427) as males. The overall age distribution according to the calendar year showed that 66.6% (951/1,427) of birds were ’1st calendar year and 16.6% (237/1,427) were ‘> 1 calendar year’. Age could not be determined in 16.7% of birds. Primary causes of admission were orphaned young (53.2%), unknown trauma (24.7%), impact with motor vehicles (5.6%), other cause (5.5%), undetermined (3.7%), illegally captive (2.1%), natural diseases (2.1%), and gunshot (1.1%). Within the breeding season the frequency of admissions due to traumas –unknown trauma (X2 = 147.108; p < 0.001)– and impact with motor vehicles (X2 = 28.528; p < 0.001) and other cause (X2 = 11.420; p = 0.003) were the most important causes. In winter, admissions were mainly related to unknown trauma and gunshot. Over the fifteen years we observed a significant increase in the orphaned young category.

To test the efficiency of playback methods to survey little owl (Athene noctua) populations we carried out two studies: (1) we recorded the replies of radio–tagged little owls to calls in a small area; (2) we recorded call broadcasts to estimate the effectiveness of the method to detect the presence of little owl. In the first study, we detected an average of 8.12 owls in the 30′ survey period, a number that is close to the real population; we also detected significant little owl movements from the initial location (before the playback) to the next locations during the survey period. However, we only detected an average of 2.25 and 5.37 little owls in the first 5′ and 10′, respectively, of the survey time. In the second study, we detected 137 little owl territories in 105 positive sample units. The occupation rate was 0.35, the estimated occupancy was 0.393, and the probability of detection was 0.439. The estimated cumulative probability of detection suggests that a minimum of four sampling times would be needed in an extensive survey to detect 95% of the areas occupied by little owls.

In recent decades agricultural landscapes in Catalonia have undergone a profound transformation as in most of Europe. Reforestation and urban development have reduced farmland and therefore the availability of suitable habitat for some bird species such as the little owl (Athene noctua). The outskirts of the city of Mataró by the Mediterranean Sea exemplify this landscape change, but still support a population of little owl where agriculture is carried out. Three resident little owls were monitored with telemetry weekly from November 2007 until the beginning of August 2008 in this suburban agricultural landscape. Mean home range ± SD was 10.9 ± 5.5 ha for minimum convex polygon (MCP100) and 7.4 ± 3.8 ha for Kernel 95% probability function (K95). Home ranges of contiguous neighboring pairs overlapped 18.4% (MCP100) or 6% (K95). Home range varied among seasons reaching a maximum between March and early August but always included the nesting site. Small forested patches were associated with roosting and nesting areas where cavities in Carob trees (Ceratonia siliqua) were important. When foraging in crop fields, the owls typically fed where crops had recently been harvested and replanted. All three owls bred successfully.

Anti–predator training of juvenile little owls was tested in a sample of recovered owls raised in captivity in Brinzal Owl Rescue Center (Madrid, Spain). Mortality caused by predators has been described previously in released individuals. Nine little owls were conditioned during their development to a naturalized goshawk and a large live rat, whose presence was paired to the owl’s alarm call. All nine owls and seven non–trained individuals were then released during the late summer and autumn and radio–tracked for six weeks to test their survival. In total 71.4% of the trained owls survived while only the 33.3% of the untrained group were alive at the end of week six. The only cause of death that was detected was predation. Antipredator training, therefore, seems to be beneficial in maximizing survival after the release of juvenile little owls.

During the last half of century, agricultural intensification within European farmlands caused the deprivation of farmland biodiversity, including farmland birds. Since then different conservation measures have been introduced to reverse declining trends of these birds. Yet, variable success of these measures suggests that habitat management requires planning at appropriate spatial scales. In this study, we examine habitat associations of the Little Owl, a rapidly declining farmland bird, within the context of Central European farmland. We collected presence/absence data from three different countries (the Czech Republic, Slovakia and Hungary) and examined habitat associations within and between regions at three different spatial scales: nest site, home range and landscape. We show that certain habitat associations are shared across all study regions, namely those involving grasslands and farm buildings that are used for foraging and nesting, respectively. Inter-regional analysis reveals that grasslands, gardens/orchards and farm buildings are most important habitats at small spatial scales, whereas at large spatial scales, the owl is positively associated with open habitats in terms of arable fields. We suggest that conservation planning should take into account both regional and inter-regional aspects of a species’ habitat associations to distinguish between common habitat requirements and local species-environment relationships. [ABSTRACT FROM AUTHOR]

Interactions between top predators and mesopredators of the same guild often result in habitat segregation restricting interactions to shared habitat edges. Although negative edge effects are recognized as important spatial patterns in the ecology of fragmented landscapes, the underlying mechanisms of predator–prey interactions resulting in negative edge effects remain unknown. To disentangle top‐down effects of intraguild predators and bottom‐up effects of shared resources on mesopredator spatial distribution, we recorded the occurrence of tawny owls Strix aluco in forests and their prey, the little owl Athene noctua in adjacent open areas over 2 yr across 687 km2 in Southern Germany. We developed a new, asymmetrical dynamic two‐species occupancy model investigating spatial interactions while accounting for imperfect detection. Little owl occupancy was strongly reduced within 150 m of forests, but only in the presence of tawny owls. Analysis of over 30 000 telemetry locations of 275 little owls showed that little owls strongly avoided areas closer than 150 m from the forest during range use. These results suggest that the negative edge effect is due to forest edge avoidance rather than direct predation. Potential confounding mechanisms such as food depletion or habitat avoidance at forest edges can be ruled out. Thus, top‐down effects caused by avoidance of intraguild top predators shape the spatial distribution of mesopredators such as the little owl. While habitat complexity mitigates multitrophic interactions within habitats, it is expected to reinforce multitrophic interactions between habitats, potentially leading to the suppression of mesopredators from suitable habitats. [ABSTRACT FROM AUTHOR]

The diet of two sympatric owl species, the long-eared owl ( Asio otus ) and the little owl ( Athene noctua ) was investigated in an arid area of southern Mongolia using pellet analysis. In total 334 pellets of long-eared owl and 52 pellets of little owl were analysed, revealing the presence of five small mammal species (Dipodidae, three Muridae and one Soricidae), small birds and invertebrate fragments. Accumulative composition plots indicated a batch size of 35 - 60 pellets was sufficient to reveal representative diet composition. Small mammals comprised the largest component of the diet of long- eared owls with four species recorded, Phodopus was the most frequently occurring (85 %), followed by Meriones (33 %). Bird and invertebrate remains were also found in long-eared owl pellets but comprised less than 2 %. In contrast, invertebrates were the highest occurring component of the diet of little owls (35 %), with small mammals occurring in only 40 % of pellets. Meriones was the most frequently recorded small mammal in little owl pellets (23 %) and contributed the greatest in terms of overall rodent biomass. There was a highly statistically significant difference in the diet of the two species (÷ 2 = 2043, d.f. = 4, P < 0.001). Levin’s measure of niche breadth was greater for little owls (0.71) than long-eared owls (0.51), but overall the two species had low niche overlap using Levin’s index (0.22). These results are discussed in relation to previous findings of these two species.