Publications

residency, migration and a compromise: adaptations to nest-site scarcity and food specialization in three fennoscandian owl species.	fennoscandian owl species differ, among other things, with respect to nest-site, food, clutch size, mate and territory fidelity, sexual size dimorphism and longevity. all these life characteristics help shaping the pattern of mobility and wintering strategies found in owl species, but it seems justifiable to regard food abundance and nest-site availability as the most prominent ones.the ural owl is a generalist feeder and nests in tree cavities which are scarce. the pair is faithful to their ter ...	1979	28309764
avian wildlife reservoir of campylobacter fetus subsp. jejuni, yersinia spp., and salmonella spp. in norway.	cloacal swabs from 540 wild-living birds were cultured for campylobacter fetus subsp. jejuni, yersinia spp., and salmonella spp. the carrier rates detected were as follows: c. fetus subsp. jejuni, 28.4%; yersinia spp., 1.2%; and salmonella spp., 0.8%. all birds were apparently healthy when captured. c. fetus subsp. jejuni was isolated from 11 of the 40 bird species examined. among birds inhabiting the city of oslo, the highest isolation rate was found in crows (corvus corone cornix) (89.8%), fol ...	1983	6338824
tularemia in a rough-legged buzzard (buteo lagopus) and a ural owl (strix uralensis).		1983	6644938
prey susceptibilities, prey utilization and variable attack efficiencies of ural owls.	to investigate the factors that influence prey utilization among predators with active prey, three series of experiments were performed in which ural owls (strix uralensis) searched for and attacked three prey species of wild mice, microtus montebelli, apodemus speciosus, and a. argenteus, in a large flight cage. over the whole study, owls attacked mice about ten times a night. the number of attacks on each prey species did not differ from that predicted by a random attack model. m. montebelli w ...	1988	28311960
identification and classification of different isolates of francisella tularensis.	the causative agent of tularemia, francisella tularensis, occurs in two main biovars, the highly virulent f. t. biovar tularensis, found in north america; and the less virulent biovar palaearctica, found all over the northern hemisphere. two other biovars have been proposed, f. t. biovar mediaasiatica and f. t. biovar palaearctica var. japonica. in sweden tularemia is most frequently observed in man and varying hares (lepus timidus), and occasionally in other species. tularemia in hares is norma ...	1993	7510445
reproductive effort and reproductive values in periodic environments.	life-history theory concerns the optimal spread of reproduction over an organism's life span. in variable environments, there may be extrinsic differences between breeding periods within an organism's life, affecting both offspring and parent and giving rise to intergenerational trade-offs. such trade-offs are often discussed in terms of reproductive value for parent and offspring. here, we consider parental life-history optimization in response to varying offspring values of a population regula ...	2000	10753074
prevalence of blood parasites in japanese wild birds.	the prevalence of blood parasites was investigated in 701 japanese wild birds for 13 years from january, 1988 to march, 2001. most of the injured or sick birds were caught in the suburbs of kobe city, hyogo prefecture and brought to the zoo for clinical care. among all the birds examined, 10.6% were infected with hematozoa belonging to three genera as plasmodium (1.7% of the samples), haemoproteus (5.1% of the samples) and leucocytozoon (4.6% of the samples), and two birds (0.29% of the samples) ...	2002	12399602
cyclic variation in seasonal recruitment and the evolution of the seasonal decline in ural owl clutch size.	plastic life-history traits can be viewed as adaptive responses to environmental conditions, described by a reaction norm. in birds, the decline in clutch size with advancing laying date has been viewed as a reaction norm in response to the parent's own (somatic or local environmental) condition and the seasonal decline in its offspring's reproductive value. theory predicts that differences in the seasonal recruitment are mirrored in the seasonal decrease in clutch size. we tested this predictio ...	2002	11916482
ural owl sex allocation and parental investment under poor food conditions.	parents are expected to overproduce the less costly sex under poor food conditions. the previously regular 3-year cycle in the abundance of voles, the main prey of the ural owl, strix uralensis, temporarily disappeared in 1999-2001. we studied ural owls' parental feeding investment and sex allocation during these poor-quality years. we sexed hatchlings and embryos in unhatched eggs of all 131 broods produced during these years. population wide, the owls produced significantly more males (56%). t ...	2003	12836010
supplementary fed ural owls increase their reproductive output with a one year time lag.	life-history components may be food-limited. we supplemented food to 18 ural owl, strix uralensis, nests during the nestling period. food supplementation led to a higher somatic condition in the female parent, but effects in males were moderate. parents delivered less food to fed nests than to control nests. offspring survival and fledging condition did not differ between control and fed nests. in the season following food supplementation, fed pairs bred 1 week earlier than control pairs and, co ...	2004	15021983
single-generation estimates of individual fitness as proxies for long-term genetic contribution.	individual fitness is a central evolutionary concept, but the question of how it should be defined in empirical studies of natural selection remains contentious. using founding cohorts from long-term population studies of two species of individually marked birds (collared flycatcher ficedula albicollis and ural owl strix uralensis), we compared a rate-sensitive (lambdaind) and a rate-insensitive (lifetime reproductive success [lrs]) estimate of individual fitness with an estimate of long-term ge ...	2004	15122499
a comparative histological study on the distribution of striated and smooth muscles and glands in the esophagus of wild birds and mammals.	musculature and glands of the esophagus in various wild birds and mammals were examined histologically. cervical and thoracic esophagi of all birds used (mallard, spot-billed duck, ural owl and hodgson's hawk-eagle) were comprised of smooth muscle fibers only. in contrast, esophagi of the nutria, japanese raccoon dog, common raccoon and japanese marten consisted largely of striated muscle fibers. in the masked palm civet, japanese macaque and bottlenose dolphin, esophageal muscle layers consiste ...	2005	15699607
a possible link between parasite defence and residual reproduction.	life-history theory centres around trade-offs between current and future reproduction, but we have little understanding of how such trade-offs are mediated. we supplementary fed ural owls (strix uralensis) during the nestling period and quantified parents' current and future life-history components as well as their physiological health by monitoring haematocrit, leucocyte profile, intra- and extracellular blood parasites. feeding led to reduced parental effort but did not improve offspring viabi ...	2007	17956387
heritability, plasticity and canalization of ural owl egg size in a cyclic environment.	avian egg size is highly variable on the population level, but is considered inflexible on the individual level. on the basis of 2969 measurements of individual eggs collected during 1981-2005, we analysed heritability, plasticity and selection on egg size in the ural owl, a long-lived bird that preys on voles. vole abundance varied in a 3-year cycle, creating varying food supply across the cycle's phases. ural owl egg size is heritable (h(2) = 60%). ural owls lay larger eggs in improved food co ...	2008	18034804
scanning electron microscopic study of the tongue in the owl (strix uralensis).	the dorsal lingual surfaces of adult owl (strix uralensis) were examined by scanning electron microscopy. the length of the tongue was about 2 cm. the tip of the tongue of the owl was bifid. three parts were distinguished in the tongue of the owl: the apex, the body and the root of the tongue. the conical region between the lingual apex and lingual root was a very wide area. there were thread-shaped processes/cells of epithelium in the lingual apex. the small or large conical papillae were obser ...	2008	19032633
survival of male tengmalm's owls increases with cover of old forest in their territory.	the loss and fragmentation of forest habitats have been considered to pose a worldwide threat to the viability of forest-dwelling animals, especially to species that occupy old forests. we investigated whether the annual survival of sedentary male tengmalm's owls aegolius funereus was associated with the cover of old coniferous forests in finland. survival and recapture probabilities varied annually with density changes in populations of the main prey (microtus voles). when this variation was co ...	2008	18080142
the impact of climate and cyclic food abundance on the timing of breeding and brood size in four boreal owl species.	the ongoing climate change has improved our understanding of how climate affects the reproduction of animals. however, the interaction between food availability and climate on breeding has rarely been examined. while it has been shown that breeding of boreal birds of prey is first and foremost determined by prey abundance, little information exists on how climatic conditions influence this relationship. we studied the joint effects of main prey abundance and ambient weather on timing of breeding ...	2011	20665047
competitive exclusion within the predator community influences the distribution of a threatened prey species.	while much effort has been made to quantify how landscape composition influences the distribution of species, the possibility that geographical differences in species interactions might affect species distributions has received less attention. investigating a predator-prey setting in a boreal forest ecosystem, we empirically show that large-scale differences in the predator community structure and small-scale competitive exclusion among predators affect the local distribution of a threatened for ...	2012	22928409
higher nest predation risk in association with a top predator: mesopredator attraction?	breeding close to top predators is a widespread reproductive strategy. breeding animals may gain indirect benefits if proximity to top predators results in a reduction of predation due to suppression of mesopredators. we tested if passerine birds gain protection from mesopredators by nesting within territories of a top predator, the ural owl (strix uralensis). we placed nest boxes for pied flycatchers (ficedula hypoleuca) in ural owl nest sites and in control sites (currently unoccupied by owls) ...	2012	22492168
selection on plasticity of seasonal life-history traits using random regression mixed model analysis.	theory considers the covariation of seasonal life-history traits as an optimal reaction norm, implying that deviating from this reaction norm reduces fitness. however, the estimation of reaction-norm properties (i.e., elevation, linear slope, and higher order slope terms) and the selection on these is statistically challenging. we here advocate the use of random regression mixed models to estimate reaction-norm properties and the use of bivariate random regression to estimate selection on these ...	2012	22837818
laboratory blood analysis in strigiformes-part i: hematologic reference intervals and agreement between manual blood cell counting techniques.	while hematologic reference intervals (ri) are available for multiple raptorial species of the order accipitriformes and falconiformes, there is a lack of valuable hematologic information in strigiformes that can be used for diagnostic and health monitoring purposes.	2015	25627556
acanthocephalans of the genus centrorhynchus (palaeacanthocephala: centrorhynchidae) of birds of prey (falconiformes) and owls (strigiformes) in slovakia.	three species of thorny-headed worms of the genus centrorhynchus were found to parasitize birds of prey and owls in the territory of the slovakia during the years 2012-2014. out of 286 examined bird individuals belonging to 23 species, only buteo buteo, buteo rufinus, falco tinnunculus (falconiformes), asio otus, strix aluco, strix uralensis and tyto alba (strigiformes) were infected by acanthocephalans. all the bird species except for s. aluco represent new host records for slovakia. the most p ...	2015	25786606
toxigenic corynebacterium ulcerans isolated from a wild bird (ural owl) and its feed (shrew-moles): comparison of molecular types with human isolates.	corynebacterium ulcerans is a pathogen causing diphtheria-like illness to humans. in contrast to diphtheria by corynebacterium diphtheriae circulating mostly among humans, c. ulcerans infection is zoonotic. the present study aimed to clarify how a zoonotic pathogen c. ulcerans circulates among wild birds and animals.	2016	27000873
exploratory plasma biochemistry reference intervals for ural owls (strix uralensis, pallas 1771) from the austrian reintroduction project.	the ural owl (strix uralensis) is the biggest forest-living owl in austria; however, it became extinct in austria through poaching and habitat loss more than half a century ago. the birds examined in the present study were breeding pairs from the reintroduction project with the aim of determining exploratory plasma biochemistry reference intervals in ural owls and evaluating the amount of biological variation between seasons, sexes, and ages. a total of 45 birds were sampled, including 13 adult ...	2016	27468020
detection and phylogenetic analysis of herpesviruses detected in wild owls in slovenia.	herpesvirus (hv) was detected using pcr in the organs of eight of 55 wild owls (14.5%) from seven species that were found dead in various locations in slovenia between 1995 and 2015. hv was detected in three species: the eurasian eagle owl (bubo bubo), ural owl (strix uralensis), and long-eared owl (asio otus). phylogenetic analysis of partial dna polymerase gene nucleotide sequences showed that the detected hvs are similar to the avian and mammal alphaherpesviruses. two sequences were very simi ...	2018	31119924
predation risk landscape modifies flying and red squirrel nest site occupancy independently of habitat amount.	habitat choice often entails trade-offs between food availability and predation risk. understanding the distribution of individuals in space thus requires that both habitat characteristics and predation risk are considered simultaneously. here, we studied the nest box use of two arboreal squirrels who share preferred habitat with their main predators. nocturnal ural owls (strix uralensis) decreased occurrence of night-active flying squirrels (pteromys volans) and diurnal goshawks (accipiter gent ...	2018	29596438
nocturnal noise and habitat homogeneity limit species richness of owls in an urban environment.	habitat loss and fragmentation are listed among the most significant effects of urbanization, which is regarded as an important threat to wildlife. owls are the top predators in most terrestrial habitats, and their presence is a reliable indicator of ecosystem quality and complexity. however, influence of urbanization on owl communities, anthropogenic noise in particular, has not been investigated so far. the aim of this study was to identify the role of noise and landcover heterogeneity in the ...	2019	31012067
monitoring 137cs concentrations in bird species occupying different ecological niches; game birds and raptors in fukushima prefecture.	this study was conducted to assess radiocesium accumulation in birds after the accident at tokyo electric power company's fukushima daiichi nuclear power station in 2011, with a particular focus on 137cs, which has a long physical half-life. results of 137cs monitoring in four game bird species including two pheasant species and two duck species (copper pheasant, green pheasant, spot-billed duck and mallard) were assessed in fukushima prefecture. we also obtained samples from rescued raptors tha ...	2019	30544020
a revision of strigiphilus (insecta: phthiraptera: philopteridae) from japan.	the japanese species of the genus strigiphilus mjöberg, 1910 (insecta: phthiraptera: philopteridae) are revised. six species are recorded, including a new species belonging to the cursitans species-group: strigiphilus stenocephalus new species, described from the type host otus bakkamoena semitorques and based on specimens originally identified and reported by uchida (1949) as strigiphilus rostratus (burmeister, 1838). a lectotype for strigiphilus laticephalus (uchida, 1949) (type host: strix al ...	2020	33055767
weather and biotic interactions as determinants of seasonal shifts in abundance measured through nest-box occupancy in the siberian flying squirrel.	it is much debated whether the direct effects of weather or biotic interactions determine species' responses to climate change. for example, an important biotic factor for herbivores in northern ecosystems is the availability of winter food. if the food availability changes because of the changing climate, it likely has major impact on the abundance of herbivores. to evaluate this, we need to know the relative roles of weather and biotic interactions, such as food availability and risk of predat ...	2020	32879335
species interactions and climate change: how the disruption of species co-occurrence will impact on an avian forest guild.	interspecific interactions are crucial in determining species occurrence and community assembly. understanding these interactions is thus essential for correctly predicting species' responses to climate change. we focussed on an avian forest guild of four hole-nesting species with differing sensitivities to climate that show a range of well-understood reciprocal interactions, including facilitation, competition and predation. we modelled the potential distributions of black woodpecker and boreal ...	2020	31804736