Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| a comparative study of deep avian foveas. | the foveas of nine avian species, initially selected for the presence of a deep fovea and representing a wide range of eye sizes and ecological habits, were studied with quantitative light microscope techniques. considerable variation was observed in the location and configuration of the avian foveas, although they appeared to be 'convexiclivate' in shape when compared with the fovea of the rhesus monkey. comparisons of foveal cell densities (receptor nuclei and ganglion cells) across species sh ... | 1975 | 811324 |
| [mercury residues in goshawk (accipiter gentilis) in 1966 and 1974 (author's transl)]. | a comparative study of liver, muscle and kidney specimens from goshawks (accipiter gentilis) shot in 1966 and 1974 respectively shows that a significant decrease in the mercury levels has taken place. the mean values in the liver specimens have changed from 2.27 mg/kg to 0.50 mg/kg, in the muscle specimens from 0.99 mg/kg to 0.20 mg/kg and in the kidney specimens from 3.06 mg/kg to 0.57 mg/kg. the main cause of this decrease is supposed to depend upon the recommendations since 1969 to avoid alky ... | 1975 | 1196855 |
| suspected lead toxicosis in a captive goshawk. | lead toxicosis was diagnosed in a 3-week-old male goshawk after evaluation of the history, clinical signs, radiographic lesions, and laboratory values. treatment with ca-edta and supportive measures was successful. the presumed source of lead was from birds that had been shot with a pellet gun and used for food. | 1991 | 1748615 |
| primitive cytokines: harbingers of vertebrate defense. | the evolution of the immune system has awarded cytokines a key role as coordinators of the immune response. the exquisite action of cytokines in fine tuning and controlling the response raises the question of whether or not these molecules have been highly conserved through evolution. gregory beck and gail habicht have isolated and characterized two major cytokines, interleukin 1 and tumor necrosis factor, from invertebrates. in this article, they speculate on the possible function of these mole ... | 1991 | 1878133 |
| surgical management of digital gryposis syndrome in a goshawk (accipiter gentilis gentilis). | digital gryposis syndrome is an acquired abnormal curvature of the digits due to an unknown etiology. past medical therapeutic efforts have had limited success, with occasional reports of spontaneous recoveries. unilateral digital flexor tendon hypertension was identified as the cause of the presenting signs in the goshawk reported in this paper. tenectomy was performed on the flexor perforatus digiti iii, flexor perforans et perforatus digiti iii, and flexor perforatus digiti iv tendons. a foot ... | 2003 | 1953584 |
| mouse (mus musculus) as intermediate host of sarcocystis sp. from the goshawk (accipiter gentilis). | sporocysts from the goshawk (accipiter gentilis) were experimentally transferred to the mouse (mus musculus). it was found that the goshawk is the host of one of the sarcosporidians inducing muscle sarcocystosis in mice. thin-walled, sporulated oocysts expelled by the goshawk measured 16.5-19.0 x 12.0-13.0 micron. those which measured 12.0-13.5 x 8.2-9.0 micron were widely elliptical, with rounded poles. no asexual reproduction of parasites was detected in the viscera of mice. the cysts started ... | 1986 | 3084365 |
| comparison of serum and lung extracts for surveys of wild animals for antibodies to francisella tularensis biovar palaearctica. | a comparative study of the antibody titer against francisella tularensis biovar palaearctica in serum and lung extract was made using different immunoassays. samples were taken from experimentally-infected goshawks (accipiter gentilis) and european beavers (castor fiber), and in a field survey of wild beavers. good accordance between the antibody titer in serum and in lung extract was found in the experimental studies. however, the antibody titer was generally one- to three-fold lower in lung ex ... | 1988 | 3280838 |
| experimental infection of five species of raptors and of hooded crows with francisella tularensis biovar palaearctica. | sixteen raptors and three hooded crows were infected experimentally with francisella tularensis biovar palaearctica. the birds were infected parenterally or per os. one goshawk, one sparrow hawk and one hooded crow died during the experimental period, and the remaining 16 birds were killed 14-77 days after the first infection. francisella tularensis was not isolated from any bird. antibody levels against f. tularensis measured in nine birds varied from 0 to 1:1,280. in one goshawk with a titer o ... | 1988 | 3280839 |
| trichomoniasis in free-living goshawks (accipiter gentilis gentilis) from great britain. | the goshawk accipiter gentilis has recently been reintroduced into parts of great britain. during the course of a study of one population, lesions of stomatitis were observed in 14 young from five broods and all the affected birds died. postmortem examination of three birds revealed live trichomonas gallinae in exudate from one, and histological findings consistent with a diagnosis of trichomoniasis were made in this and one other bird. it is suggested that trichomoniasis may be a significant mo ... | 1988 | 3352101 |
| high-altitude respiration of birds. the primary structures of the major and minor hemoglobin component of adult goshawk (accipiter gentilis, accipitrinae). | the primary structures of the hemoglobin components hb a and hb d of the adult goshawk (accipiter gentilis) are presented. the globin chains were separated on cm-cellulose in 8m urea buffer. component separation was achieved by fplc-chromatography on a tsk sp-5pw column in phosphate-buffers with a linear gradient of nacl. the amino-acid sequences were established by automated edman degradation of the globin chains and of the tryptic peptides in liquid-phase and gas-phase sequenators. the sequenc ... | 1987 | 3606820 |
| the role of birds as definitive hosts and intermediate hosts of heteroxenous coccidians. | sarcocystis-like oocysts-sporocysts were found in four species of owls (asio otus, bubo bubo, strix aluco, and tyto alba) and in five species of predatory birds (accipiter gentilis, accipiter nisus, buteo buteo, circus aeruginosus, falco tinnunculus). in addition, the muscles of 15 of 41 (36.5%) pheasants (phasianus colchicus) and one of two jays (garrulus glandarius) were found to harbor three types of sarcocystis. three of 15 (20%) infected pheasants had type i cystozoites (6-8 x 2 microns) in ... | 1984 | 6439858 |
| prevalence of aspergillus fumigatus in free-living goshawks (accipiter gentilis atricapillus). | during the fall migration of 1972 and 1973 unusually large numbers of goshawks (accipiter gentilis atricapillus) were counted at hawk ridge in duluth, minnesota. these birds were sampled for prevalence of fungi of the genus aspergillus. fungi of this genus were recovered from 26 of 49 birds (53%) in 1972 and 4 of 45 (7%) birds in 1973. aspergillosis was confirmed at necropsy in three wild goshawks in 1972, but none in 1973. the disease was further confirmed at necropsy in 8 of 12 (67%) goshawks ... | 1980 | 7001046 |
| [tuberculosis in raptorial birds. clinical cases and differential diagnosis]. | four cases of avian tuberculosis in two goshawks (accipiter gentilis gentilis), a lanner falcon (falco biarmicus sp.) and a kestrel (falco tinnunculus tinnunculus) are reported. all birds, except for the kestrel, were affected with generalized tuberculosis. clinically, the lanner falcon and kestrel showed lameness due to tuberculous arthritis of a knee joint. one of the goshawks died suddenly. on post-mortem examination, the bird was found to be emaciated, and there was involvement of one knee j ... | 1982 | 7135364 |
| [parasites of austrian birds of prey (falconiformes)]. | during the examination of 158 birds of prey -- buteo buteo (85), falco tinnunculus (30), accipiter gentilis (19), accipiter nisus (18), circus aeruginosus (2), circus pygargus (1), pandion haliaetus (1), pernis apivorus (1), falco subbuteo (1) and faeces samples of falco tinnunculus 4 protozoan species, 1 trematode species, 2 cestode species, 13 nematode species, 2 acanthocephalan species and 5 mallophaga species could be detected. in the buzzard, kestrel and goshawk a new species of capillaria ... | 1980 | 7212374 |
| [comparative studies of the release and ability to survive of game pheasants (phasianus colchicus sp.) from intensive and extensive husbandry]. | artificially reared pheasants had been released at an age of 10 weeks on two stands in a suitable habitat with a wild pheasant population in lower saxony, germany. two groups (200 pheasants reared in large fly-aviaries, 200 pheasants reared in dark stables) were bought from commercial breeders who offer pheasants for restocking wild populations. some of the released pheasants were marked with radio-transmitters. there was no significant difference in survival rate between the two rearing groups. ... | 1995 | 7555681 |
| molecular characterization of a 6.6-kilodalton borrelia burgdorferi outer membrane-associated lipoprotein (lp6.6) which appears to be downregulated during mammalian infection. | isolated outer membranes of borrelia burgdorferi 297 were utilized to obtain partial amino acid sequence information for a low-molecular-weight, outer membrane-associated polypeptide. degenerate oligonucleotide primers based upon this information were used to amplify a 100-bp probe for detection of the corresponding full-length gene within a b. burgdorferi total genomic library. the relevant open reading frame (orf) encoded a polypeptide comprised of a 17-amino-acid putative signal peptide termi ... | 1997 | 9009290 |
| embryonic and neonatal mortality from salmonellosis in captive bred raptors. | in a captive breeding center near rome (italy), cases of embryonic and neonatal death were recorded during the breeding seasons in the european eagle owl (bubo bubo), peregrine falcon (falco peregrinus), buzzard (buteo buteo), and lanner falcon. (falco biarmicus). salmonella havana and s. virchow were isolated. three pulli, clinically infected with s. havana, were successfully treated with enrofloxacin. from two groups of healthy 3- to 4-wk-old eagle owls, salmonella sp. group 61 (61:r:-) and s. ... | 1998 | 9476227 |
| respiratory nematodiases in raptors in quebec. | this is a retrospective study on wild raptors submitted to the université de montréal (quebec, canada) from 1989 to 1996. cyathostoma spp. (nematoda: syngamidae) adults and/or eggs were found in air sacs, lungs, bronchi, and trachea of 12 raptors (falconiformes and strigiformes) from quebec, canada, belonging to eight different species, five of which are first host records for this parasite: barred owl (strix varia), snowy owl (nyctea scandiaca), northern harrier (circus cyaneus), northern gosha ... | 1999 | 10231766 |
| a juvenile sichuan golden monkey (rhinopithecus roxellana) predated by a goshawk (accipiter gentilis) in the qinling mountains | 1999 | 10394069 | |
| prevalence of haematozoa in birds of prey in catalonia, north-east spain. | blood samples from birds of prey, 95 strigiformes and 190 falconiformes, were examined for the presence of haematozoan parasites. the birds had been admitted to a raptor recovery centre in catalonia, north-east spain. parasites were counted in positive smears. a second blood sample was obtained from 99 birds at least seven days after their arrival at the centre. haematozoa were detected in all seven species of strigiformes and in nine of 19 species of falconiformes. the overall prevalences in th ... | 1999 | 10399244 |
| organization of telomere sequences in birds: evidence for arrays of extreme length and for in vivo shortening. | telomeres are the specialized ends of chromosomes consisting of highly conserved repeat (5'-ttaggg-3')(n) sequences. lack of information regarding the existence of an in vivo telomere clock function in birds, conflicting data regarding telomere array length in the chicken model, and the paucity of molecular telomere information for other avian species led us to study telomere array organization within and among 18 species and subspecies of birds. most of the species contained between 2% and 4% t ... | 2000 | 11060464 |
| amino acid sequences of hemoglobin from guinea fowl (numida meleagri) and california quail (lophortyx californica) with phylogenetic analysis of major groups of galliformes. | we determined the complete amino acid sequences of the hemoglobin of two species, guinea fowl and california quail, in galliformes from intact globin chain and chemical cleavage fragments in order to analyze the molecular evolution of hemoglobin for the classification of galliformes. galliformes have two types of hemoglobin components, hba and hbd, which consist of identical beta chain and different alpha chains. the sequences are similar to globin chains of galliformes reported previously. thes ... | 2000 | 11195970 |
| [occurrence of parasites in indigenous birds of prey and owls]. | in the present paper a general overview on parasites in birds of prey and owls is given. this part is followed by a study investigating the prevalences and species of parasites in free-ranging birds of prey and owls in berlin and brandenburg state, germany. over a one year period, 84 birds of prey and owls of the following species were examined for the presence of endo- and ectoparasites: common buzzard (buteo buteo) (n = 32), kestrel (falco tinnunculus) (n = 20), sparrowhawk (accipiter nisus) ( ... | 2002 | 11852683 |
| pcdds/pcdfs, pcbs, and organochlorine pesticides in eggs of eurasian sparrowhawks (accipiter nisus), hobbies (falco subbuteo), and northern goshawks (accipiter gentilis) collected in the area of berlin-brandenburg, germany. | concentrations of polychlorinated dibenzo-p-dioxins (pcdds), polychlorinated dibenzofurans (pcdfs), polychlorinated biphenyls (pcbs), and organochlorine (oc) pesticides were measured in unsuccessfully hatched eggs of three different kinds of predatory birds: 3 eggs of sparrowhawks, 7 eggs of hobbies, and 16 eggs of goshawks collected in the german region of berlin-brandenburg. using toxic equivalency factors for birds, eggs of hobbies contained mean concentrations of 478 pg teq/g fat and 551 pg ... | 2002 | 11994791 |
| organochlorines in egg samples from norwegian birds of prey: congener-, isomer- and enantiomer specific considerations. | the content of chlorinated persistent organic pollutants was determined in a total of 44 egg samples from 8 different raptor species collected throughout norway in the period 1991-1997. the content of 8 chlorinated bornanes, 9 chlorinated pesticides, and 15 polychlorinated biphenyl congeners (pcb) were determined. the highest average concentrations for pcb were found for eggs from white-tailed sea eagle and peregrine falcon (average sum pcb concentration: 8.9 and 9.1 microg/g wet weight (w.w.), ... | 2002 | 12150443 |
| persistent organochlorine contaminants in eggs of northern goshawk and eurasian buzzard from northeastern spain: temporal trends related to changes in the diet. | persistent organochlorine compounds (pesticides and polychlorinated biphenyls) were determined in 24 northern goshawk (accipiter gentilis) and eight eurasian buzzard (buteo buteo) samples of eggs collected between 1988 and 1999 in la segarra (northeast spain), in order to evaluate the changes in exposure and detrimental effects during this period. in the study area, both species exhibited similar levels of contamination, which may be related to their similar diet, mainly based on european rabbit ... | 2003 | 12547524 |
| effects of experimental food supplementation on movements of juvenile northern goshawks (accipiter gentilis atricapillus). | food availability is thought to strongly influence the leaving phase of natal dispersal in animals with condition-dependent dispersal. we conducted a food supplementation experiment to determine the influence of extra food on the onset of dispersal and early dispersal movement patterns of 42 radio-tagged northern goshawks (accipiter gentilis atricapillus) from 28 broods in north-central new mexico during 1992 and 1993. we randomly assigned half of the broods each year as treatments and the other ... | 2003 | 12647170 |
| measurement of plasma corticosterone and fecal glucocorticoid metabolites in the chicken (gallus domesticus), the great cormorant (phalacrocorax carbo), and the goshawk (accipiter gentilis). | a method for the non-invasive measurement of glucocorticoid metabolites in feces of chickens was established and validated. after high-performance liquid chromatography (hplc) the presence of at least two fecal immunoreactives was demonstrated, one co-eluting with authentic corticosterone, whereas the second substance migrates close to corticosterone sulphate. we investigated the relationship between corticosterone in blood plasma obtained by a vena brachialis catheter and fecal samples in group ... | 2003 | 12714017 |
| bird skins in museum collections: are they suitable as indicators of environmental metal load after conservation procedures? | to find out whether modern conservation treatments alter the level of metals in feathers, we analysed the content of 10 metals in feathers before and after skins were washed with detergent and treated with eulan u-33 (a commonly used preservative at museums). feathers of 31 birds of goshawk accipiter gentilis, eagle owl bubo bubo. feral pigeon columba livia domest, and common eider somateria mollissima were analysed. we found that in most cases metals were partly washed out of the feathers, but ... | 2003 | 12889635 |
| environmental contaminants in liver and kidney of free-ranging northern goshawks (accipiter gentilis) from three regions of germany. | the northern goshawk (accipiter gentilis) is a top predator in the terrestrial food web of large parts of the holarctic. due to its sedentary nature and well-investigated feeding ecology, it represents the most suitable bird of prey species in continental europe for monitoring environmental pollutants. we analyzed the levels of organochlorine pesticides, polychlorinated biphenyls (pcb), and nonessential heavy metals in organ samples of 62 free-ranging northern goshawks found dead or injured in g ... | 2003 | 12948182 |
| [pasteurellosis in two raptores: the goshawk and sparrow-hawk]. | 1956 | 13327523 | |
| helminths isolated from the digestive tract of diurnal raptors in catalonia, spain. | the prevalence of parasitic helminths in the digestive tract of 119 diurnal raptors (falconiformes), which had died in a wildlife rehabilitation centre in catalonia, was studied. the birds belonged to 13 species, with 100 of them (84 per cent) being kestrels (falco tinnunculus), buzzards (buteo buteo), sparrowhawks (accipiter nisus) and goshawks (accipiter gentilis). ninety-five of the birds (79.8 per cent) were infected with helminths. nematodes were the most frequently found helminth (75.6 per ... | 2004 | 14725424 |
| chlorinated hydrocarbons and shell thinning in eggs of (accipiter) hawks in ontario, 1986-1989. | eggs of sharp-shinned hawks (accipiter striatus), cooper's hawks (a. cooperii), and northern goshawks (a. gentilis) were collected from nests in south-central ontario from 1986 to 1989. detectable levels of the chlorinated hydrocarbons dde, ddt, ddd, mirex, photomirex, cis-nonachlor, trans-nonachlor, oxychlordane, dieldrin, heptachlor expoxide, hcb and pcb were present in all the eggs analyzed. mean contaminant levels were highest in sharp-shinned hawks, slightly lower in cooper's hawks, and sig ... | 1994 | 15091636 |
| evaluating habitat as a surrogate for population viability using a spatially explicit population model. | because data for conservation planning are always limited, surrogates are often substituted for intractable measurements such as species richness or population viability. we examined the ability of habitat quality to act as a surrogate for population performance for both red-shouldered hawks (buteo lineatus) and northern goshawks (accipiter gentilis). we compared simple measures of habitat quality to estimates of population growth rates obtained from a spatially explicit model of population dyna ... | 2004 | 15141448 |
| congenital neuropathy and dilution of feather melanin in nestlings of urban-breeding northern goshawks (accipiter gentilis). | a pair of northern goshawks (accipiter gentilis) breeding in a public park in the city center of hamburg, germany, raised 12 healthy and five aberrant offspring between 1996 and 2000. aberrant nestlings (three males and two females) had pale silver-blue plumage and displayed severe locomotor disorders. histopathologically, the defects were characterized by adendritic feather melanocytes and mild degeneration of the cerebellar white matter. epidemiologic results were suggestive of a hereditary au ... | 2004 | 15193082 |
| competitive interactions among raptors in boreal forests. | we examined inter-specific interactions among goshawks ( accipiter gentilis), common buzzards (buteo buteo) and honey buzzards (pernis apivorus) in western finland in 1983-1996. because goshawks are among the largest birds of prey species in boreal forests they may take over the nest of smaller and less-competitive forest-dwelling raptors when searching for suitable places for breeding. accordingly, more than half of newly established goshawk territories were found on the territories previously ... | 2004 | 15375689 |
| lead in feathers and delta-aminolevulinic acid dehydratase activity in three raptor species from an unpolluted mediterranean forest (southeastern spain). | this paper presents the levels of lead found in the feathers of adult and blood of nestlings of booted eagle (hieraaetus pennatus), european buzzard ( buteo buteo), and goshawk (accipiter gentilis) sampled in the 1999 and 2000 breeding seasons in a mediterranean forest of the province of murcia (southeastern spain) located far from potential sources of metal contamination. levels of delta-aminolevulinic acid dehydratase activity (delta-alad) in blood were also measured in the nestlings. lead con ... | 2004 | 15386153 |
| reduction of organochlorine residues in goshawk eggs (accipiter gentilis) from northern germany (1971-2002) and increasing eggshell index. | we investigated unhatched eggs (n = 57) of goshawks (accipiter gentilis) from the period 1988--2002 and compared them with eggs (n = 134) from 1971--1978. mean concentrations of pcbs, sigmaddt and hcb in the earlier period were (mg kg(-1) lipid weight) 50.1, 126.6, and 117.7, while the values from the later period were statistically significantly lower: 27.7, 4.1, 0.1, respectively. nevertheless, the concentration of pcb is relatively constant during the last 8-10 years. the variability of resid ... | 2004 | 15666679 |
| pathologic and immunohistochemical findings in goshawks (accipiter gentilis) and great horned owls (bubo virginianus) naturally infected with west nile virus. | the carcasses of 25 great horned owls and 12 goshawks were investigated for west nile virus (wnv) infection by immunohistochemistry (ihc) performed on various organs, including brain, spinal cord, heart, kidney, eye, bone marrow, spleen, liver, lungs, pancreas, intestine, and proventriculus, using a wnv-antigen-specific monoclonal antibody and by wnv-specific reverse transcriptase-polymerase chain reaction (rt-pcr), performed on fresh brain tissue only. wnv infection was diagnosed by ihc in all ... | 2005 | 16094831 |
| prevalence of trichomonas gallinae in northern goshawks from the berlin area of northeastern germany. | in recent years, the northern goshawk (accipiter gentilis) has colonized suburban and urban areas in berlin, germany, and elsewhere in europe. because of the high proportion of feral pigeons (columba livia f. domestica) in their diet, urban goshawks are suspected to have a high infection rate with trichomonas gallinae. therefore, from 1998 to 2001, we examined 269 nestlings from 90 nests for infection with t. gallinae by culture of swabs taken from the oropharynx and checked their oropharynx for ... | 2005 | 16107664 |
| brominated flame retardants and other organobromines in norwegian predatory bird eggs. | a set of 62 unhatched eggs was collected from six different predatory bird species throughout norway after incubation period was completed. they were analysed for pbde, pbb, tbbp a and naturally occurring halogenated compounds. bde 47, 99 and 153 were the dominating congeners, with species dependent pbde patterns. bde 153 was observed as the most abundant congener in eggs of peregrine falcon, golden eagle and merlin. the highest pbde level (sum of nine congeners) was found in eggs of white-taile ... | 2005 | 16182862 |
| age-dependent diet choice in an avian top predator. | age-dependent breeding performance is arguably one of the best-documented phenomena in ornithology. the existence of age-related trends has major implications for life-history theory, but the proximate reasons for these patterns remain poorly understood. it has been proposed that poor breeding performance of young individuals might reflect lack of foraging skills. we investigated this possibility in a medium-sized, powerful raptor-the northern goshawk accipiter gentilis. male goshawks are respon ... | 2006 | 16537129 |
| lineage 1 and 2 strains of encephalitic west nile virus, central europe. | two different west nile virus (wnv) strains caused lethal encephalitis in a flock of geese and a goshawk in southeastern hungary in 2003 and 2004, respectively. during the outbreak in geese, 14 confirmed human cases of wnv encephalitis and meningitis were reported in the same area. sequencing of complete genomes of both wnv strains and phylogenetic analyses showed that the goose-derived strain exhibits closest genetic relationship to strains isolated in 1998 in israel and to the strain that emer ... | 2006 | 16704810 |
| post-fledging survival of northern goshawks: the importance of prey abundance, weather, and dispersal. | effective wildlife conservation strategies require an understanding of how fluctuating environmental conditions affect sensitive life stages. as part of a long-term study, we examined post-fledging and post-independence survival of 89 radio-marked juvenile northern goshawks (accipiter gentilis) produced from 48 nests in northern arizona, usa, during 1998-2001. information-theoretic methods were used to examine within- and among-year variation in survival relative to environmental (prey abundance ... | 2006 | 16705989 |
| food-limitation in a generalist predator. | investigating food-limitation in generalist predators is difficult, because they can switch to alternative prey, when one of their staple prey becomes scarce. apart from data on the dynamics of the predator population, a robust study requires: (i) a documentation of the predator's entire prey base; and (ii) an experimental or natural situation, where profitable dietary shifts are impossible, because several preferred prey species decline simultaneously. here, we provide a detailed description of ... | 2006 | 16846915 |
| a mechanistic approach to evaluation of umbrella species as conservation surrogates. | although species with large area requirements are sometimes used as umbrella species, their general utility as conservation tools is uncertain. we surveyed the species diversity of birds, butterflies, carabids, and forest-floor plants in forest sites across an area (1,600 km2) in which we delineated large breeding home ranges of northern goshawk (accipiter gentilis). we tested whether protection of the home ranges could serve as an effective umbrella to protect sympatric species of the four taxa ... | 2006 | 17002768 |
| selective predation on utah prairie dogs. | predation always affects demography and population dynamics, but removal of certain types of individuals is especially consequential. predators strike quickly and commonly avoid areas with human observers, however, and thereby make it difficult to document patterns of predation under natural conditions. at a colony of marked utah prairie dogs (cynomys parvidens), a high frequency of predation in 2005 provided an unusual opportunity to examine susceptibility of five types of individuals to predat ... | 2006 | 17004225 |
| interactions between habitat heterogeneity and food affect reproductive output in a top predator. | 1. habitat heterogeneity has important repercussions for species abundance, demography and life-history patterns. while habitat effects have been more thoroughly studied in top-down situations (e.g. in association with predation), their role in bottom-up situations (e.g. in association with food abundance) has been less explored and the underlying mechanism(s) behind the ecological patterns have not commonly been identified. 2. with material from 1993 to 2003, we test the hypothesis that the rep ... | 2007 | 17302847 |
| examination of mercury concentration in the feathers of 18 species of birds in southwest iran. | this paper presents the levels of mercury (hg) in tail feathers from different species of birds, in southwest iran (khuzestan to persian gulf). between april and october 2005, we collected tail feathers from 77 birds belonging to 18 species, mostly raptor birds. the birds were collected for the museum natural history, faculty of natural resources and marine sciences of tarbiat modares university. hg concentrations were evaluated in relation to taxonomic affiliation and trophic level. feather hg ... | 2007 | 17307157 |
| long-term demographic analysis in goshawk accipiter gentilis: the role of density dependence and stochasticity. | density dependence and environmental stochasticity are both potentially important processes influencing population demography and long-term population growth. quantifying the importance of these two processes for population growth requires both long-term population as well as individual-based data. i use a 30-year data set on a goshawk accipiter gentilis population from eastern westphalia, germany, to describe the key vital rate elements to which the growth rate is most sensitive and test how en ... | 2007 | 17356810 |
| predation as a landscape effect: the trading off by prey species between predation risks and protection benefits. | 1. predators impose costs on their prey but may also provide benefits such as protection against other (e.g. nest) predators. the optimal breeding location in relation to the distance from a nesting raptor varies so as to minimize the sum of costs of adult and nest predation. we provide a conceptual model to account for variation in the relative predation risks and derive qualitative predictions for how different prey species should respond to the distance from goshawk accipiter gentilis nests. ... | 2007 | 17439478 |
| applying choice experiments to valuing the different types of environmental issues in japan. | in this study, improvements of different types of environmental issues in japan, (i) reduction of mortality risk due to exposure to suspended particulate matter (spm), (ii) improvement of the water quality of an urban river, and (iii) protection of goshawks, were evaluated in monetary terms using choice experiments. it was found that the reduction of mortality risk and the improvement of the water quality were highly valued, while residents did not place high value on the protection of goshawks. ... | 2007 | 17475394 |
| prevalence of mycoplasmas in eggs from birds of prey using culture and a genus-specific mycoplasma polymerase chain reaction. | mycoplasmas are commensals and pathogens of different avian species, especially poultry and passeriforms. the role of mycoplasmas in raptors has not yet been completely determined, and especially not the possibility of vertical transmission. therefore 424 raptor eggs were examined for the occurrence of mycoplasmas using culture, and 155 of these eggs with a mycoplasma genus-specific polymerase chain reaction (pcr) assay. this pcr was tested for its sensitivity and specificity, especially for use ... | 2007 | 17479375 |
| pathogenicity of mycoplasma lipofaciens strain ml64, isolated from an egg of a northern goshawk (accipiter gentilis), for chicken embryos. | some mycoplasma species are well-known avian pathogens and are of importance in poultry breeder flocks due to their pathogenic potential for embryos. mycoplasmas are regularly detected in birds of prey, and a strain of mycoplasma lipofaciens that was isolated from an egg of a northern goshawk (accipiter gentilis) was examined for its pathogenicity in specific pathogen free chicken embryos since birds of prey eggs were not available for this purpose. the strain was found to be pathogenic, causing ... | 2007 | 17479376 |
| malaria and risk of predation: a comparative study of birds. | predators have been hypothesized to prey on individuals in a poor state of health, although this hypothesis has only rarely been examined. we used extensive data on prey abundance and availability from two long-term studies of the european sparrowhawk (accipiter nisus) and the eurasian goshawk (accipiter gentilis) to quantify the relationship between predation risk of different prey species and infection with malaria and other protozoan blood parasites. using a total of 31 745 prey individuals o ... | 2007 | 17536704 |
| territory occupancy rate of goshawk and gyrfalcon: no evidence of delayed numerical response to grouse numbers. | two recent studies on territory occupancy rates of goshawk accipiter gentilis and gyrfalcon falco rusticolus report a 2-3-year-delayed numerical response to grouse numbers, which is a requirement for a hypothesis of predator-generated grouse cycles. the time lags were assumed to reflect the average age of sexual maturity in the raptor species. in southern norway, however, subadult (two-year-old) goshawk hens occupied only 18-25% of territories where occupancy was not recorded in the preceding ye ... | 2007 | 17549523 |
| clinical and pathologic features of lineage 2 west nile virus infections in birds of prey in hungary. | in the southeast of hungary a sparrow hawk (accipiter nisus) and several goshawk (accipiter gentilis) fledglings succumbed to encephalitis manifesting as an acute neurological disease during the summers of 2004 and 2005. both years the causative agent was identified as a lineage 2 west nile virus. this is the first description of clinical, pathological and immunohistochemical findings of infection caused by a neuroinvasive, lineage 2 west nile virus and the first evidence of its circulation in c ... | 2007 | 17627436 |
| pathogenicity of mycoplasma lipofaciens strain ml64 for turkey embryos. | mycoplasma lipofaciens strain ml64, isolated from an egg of a northern goshawk (accipiter gentilis), has been found to be pathogenic for chicken embryos causing mortality during the first 2 weeks of incubation. the same strain was inoculated in turkey embryos to evaluate its pathogenicity and its ability to be transmitted laterally in the hatchery. the strain was found to be pathogenic for turkey embryos, causing a high mortality (88.9%) during late incubation as well as haemorrhages of the legs ... | 2007 | 17899463 |
| habitat classification modeling with incomplete data: pushing the habitat envelope. | habitat classification models (hcms) are invaluable tools for species conservation, land-use planning, reserve design, and metapopulation assessments, particularly at broad spatial scales. however, species occurrence data are often lacking and typically limited to presence points at broad scales. this lack of absence data precludes the use of many statistical techniques for hcms. one option is to generate pseudo-absence points so that the many available statistical modeling tools can bb used. tr ... | 2007 | 17913135 |
| organochlorine residues in booted eagle (hieraaetus pennatus) and goshawk (accipiter gentilis) eggs from southeastern spain. | most organochlorine (oc) use has been banned in spain, but these compounds are persistent and may still adversely affect predatory birds. data generally are lacking, however. residues of hexachlorobenzene, alpha-hexachlorocyclohexane, lindane, hexachloro-octahydro-epoxy-dimethanonaphthalene, ddt, dichlorodiphenyldichloroethane, dichlorodiphenyldichloroethylene (dde), and polychlorinated biphenyls (pcbs) were measured in 22 failed eggs of booted eagles (hieraaetus pennatus) and goshawks (accipite ... | 2007 | 17941741 |
| 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 |
| an avipoxvirus infection in a goshawk (accipiter gentilis). | this report describes the nodular lesions found on a young, male european goshawk (accipiter gentilis) which were found to be poxvirus lesions in conjunction with a staphylococcus aureus infection. treatment consisted of surgical removal of the two lesions and amoxicillin/clavulanic acid. the diagnosis of a poxvirus infection was suspected by histology and confirmed with transmission electron microscopy. to our knowledge the goshawk has been reported as being susceptible to avipoxvirus infection ... | 1998 | 18483972 |
| food regulates reproduction differently in different habitats: experimental evidence in the goshawk. | food supplementation experiments have been widely used to get detailed insight into how food supply contributes to the reproductive performance of wild animals. surprisingly, even though food seldom is distributed evenly in space, variation in local habitat quality has usually not been controlled for in food supplementation studies. with results from a two-year feeding experiment involving a habitat-sensitive avian top predator, the northern goshawk accipiter gentilis, we show that treatment eff ... | 2008 | 18589533 |
| an efficient multivariate approach for estimating preference when individual observations are dependent. | 1. we discuss aspects of resource selection based on observing a given vector of resource variables for different individuals at discrete time steps. a new technique for estimating preference of habitat characteristics, applicable when there are multiple individual observations, is proposed. 2. we first show how to estimate preference on the population and individual level when only a single site- or resource component is observed. a variance component model based on normal scores in used to est ... | 2008 | 18624740 |
| the establishment of an urban bird population. | 1. despite the accelerating global spread of urbanized habitats and its associated implications for wildlife and humans, surprisingly little is known about the biology of urban ecosystems. 2. using data from a 60-year study period, this paper provides a detailed description of how the northern goshawk accipiter gentilis l.--generally considered a shy forest species--colonized the city of hamburg, germany. six non-mutually exclusive hypotheses are investigated regarding the environmental factors ... | 2008 | 18627420 |
| clinical signs and diagnosis of thiamine deficiency in juvenile goshawks (accipiter gentilis). | between 2002 and 2006, a large number of juvenile northern goshawks (accipiter gentilis) with central nervous signs were examined. they were aged between 45 and 55 days and had been fed on frozen and thawed day-old chicks. high-performance liquid chromatography showed that the birds had whole blood thiamine levels between 2.2 and 6.0 microg/l; the concentrations of other blood constituents were within their reference ranges. treatment with thiamine hydrochloride rapidly resolved the clinical sig ... | 2008 | 18708655 |
| a survey of the bacterial flora of the feet of free-living goshawks (accipiter gentilis). | the feet of goshawks (accipiter gentilis) were swabbed. bacteriological examination demonstrated that the feet were colonised by organisms from many genera some of which were recognised avian pathogens. | 1979 | 18770453 |
| [sem studies on the connective tissue cores of the lingual papillae of the northern goshawk (accipiter gentilis)]. | the lingual papillae and their connective tissue cores (ctcs) of the northern goshawk were examined by scanning electron microscopy (sem). the length of the tongue was approximately 2.5 cm. the median groove divided the body of the tongue into symmetrical parts. at a point approximately 2/3 of the length, there were large conical papillae between the body and the root of the tongue, the apices of which were pointed towards the posterior part of the tongue. under the light microscopy, the filifor ... | 2008 | 18807946 |
| time-dependent recovery of mycoplasma lipofaciens (strain ml64) from incubated infertile chicken eggs and dead in shell chicken embryos. | mycoplasmas are pathogens of different avian species, and they are able to be vertically transmitted. even detected, mycoplasma prevalence in raptor eggs is very low. in contrast to poultry, raptor eggs submitted for investigations are usually incubated. to investigate the influence of incubation length on the recovery of mycoplasmas from eggs, infertile specific-pathogen-free chicken eggs and embryos were infected with mycoplasma lipofaciens (strain ml64), which had previously been isolated fro ... | 2008 | 18939632 |
| genetic data from 28 str loci for forensic individual identification and parentage analyses in 6 bird of prey species. | twenty-eight str loci were screened in wild populations of six bird of prey species providing allele frequencies and population genetic parameters necessary for the application of strs in wildlife forensic genetic casework. individual str loci were validated according to forensic recommendations in specimens of golden eagle (aquila chrysaetos), goshawk (accipiter gentilis), merlin (falco columbarius), peregrine falcon (falco peregrinus), gyr falcon (falco rusticolus) and saker falcon (falco cher ... | 2009 | 19215871 |
| viability selection on prey morphology by a generalist predator. | prey use their locomotory capacity to escape predators, and there should thus be strong viability selection on locomotory morphology of prey. we compared feather morphology of wood pigeons columba palumbus killed by goshawks accipiter gentilis with that of survivors to quantify directional and quadratic selection on primary and rectrix feathers. the goshawk is mainly a predator attacking by surprise, leaving wood pigeons with an ability to accelerate fast at a selective advantage. there was dire ... | 2009 | 19344382 |
| use of random amplified polymorphic dna analysis and single-enzyme amplified fragment length polymorphism in molecular typing of ornithobacterium rhinotracheale strains. | ornithobacterium rhinotracheale (ort) is a bacterium common to commercial poultry and wild birds throughout the world. it is also known as a causative agent of respiratory diseases. a total of 93 ort isolates originating from chickens, pigeons, ostriches, quail, turkeys, and an asian crested goshawk (accipiter trivirgatus) in taiwan, between 2004 and 2006, were used in this study. high genetic similarity (97%-100%) in 16s rrna sequence was revealed among the 50 randomly selected isolates, in add ... | 2009 | 19432012 |
| use of random amplified polymorphic dna to identify several novel markers for sex identification in the crested serpent eagle and crested goshawk. | the crested serpent eagle (spilornis cheela hoya) has no distinct sexual dimorphic traits. in the current study, we report the results of an ee0.6 (ecori 0.6-kb fragment) sequence applied to s. cheela hoya and a novel random amplified polymorphic dna (rapd) marker that can be used to sex individuals within the species s. cheela hoya and accipiter trivigatus formosae (crested goshawk). we used sex-specific primers for the avian chd1 (chromo-helicase-dna-binding 1) gene and the ee0.6 sequence in p ... | 2009 | 19560806 |
| relationships between organohalogen contaminants and blood plasma clinical-chemical parameters in chicks of three raptor species from northern norway. | organohalogen contaminants (ohcs) may affect various physiological parameters in birds including blood chemistry. we therefore examined blood plasma clinical-chemical parameters and ohcs in golden eagle, white-tailed eagle and goshawk chicks from northern norway. correlation analyses on pooled data showed that alkaline phosphatase (alkp), glucose and creatinine were significantly negatively correlated to various ohcs (all: p<0.05; r: -0.43 to -0.55; n=23), while alanine aminotransferase (alat), ... | 2010 | 19800686 |
| sarcocystis calchasi sp. nov. of the domestic pigeon (columba livia f. domestica) and the northern goshawk (accipiter gentilis): light and electron microscopical characteristics. | a novel highly pathogenic sarcocystis species has been shown to cycle between the northern goshawk (accipiter gentilis) as definitive host and the domestic pigeon (columba livia f. domestica) as intermediate host. however, genetically based characteristics are only available from very few bird-infecting sarcocystis species. we therefore further characterised morphological properties of this protozoan in both hosts. using light and electron microscopy, oocysts and sporocysts as well as schizonts ... | 2010 | 20033211 |
| commentaries on premastication: the second arm of infant and young child feeding for health and survival? by gretel pelto, yuanyuan zhang & jean-pierre habicht. | 2010 | 20055927 | |
| sarcocystis species lethal for domestic pigeons. | a large number of sarcocystis spp. infect birds as intermediate hosts, but pigeons are rarely affected. we identified a novel sarcocystis sp. that causes lethal neurologic disease in domestic pigeons in germany. experimental infections indicated transmission by northern goshawks, and sequence analyses indicated transnational distribution. worldwide spread is possible. | 2010 | 20202429 |
| sarcocystis calchasi is distinct to sarcocystis columbae sp. nov. from the wood pigeon (columba palumbus) and sarcocystis sp. from the sparrowhawk (accipiter nisus). | sarcocystis calchasi has been identified as causative agent of a newly discovered central nervous disease in domestic pigeons (columba livia f. domestica) observed for the first time in germany in 2006. initial studies have indicated that this parasite is highly pathogenic for domestic pigeons after ingestion of low doses of sporocysts shed by the northern goshawk (accipiter gentilis). here we tested whether phylogenetically related birds might regularly harbor sarcocystis species. five wood pig ... | 2010 | 20381254 |
| accuracy and reproducibility of the tonovet rebound tonometer in birds of prey. | to examine the accuracy and reproducibility of intraocular pressure (iop) measurements obtained by the tonovet rebound tonometer. animals studied freshly enucleated healthy eyes of 44 free-ranging birds of prey out of the species haliaeetus albicilla, accipiter gentilis, accipiter nisus, buteo buteo, falco tinnunculus, strix aluco, asio otus and tyto alba euthanized because of unrelated health problems. | 2010 | 20840094 |
| unusual biphasic disease in domestic pigeons (columba livia f. domestica) following experimental infection with sarcocystis calchasi. | a novel sarcocystis species has recently been reported in the domestic pigeon (columba livia f. domestica) as intermediate host, causing severe central nervous signs similar to paramyxovirus-1 or salmonella typhimurium var. cop. infection. transmission of the parasite via the northern goshawk (accipiter gentilis) as definitive host has been established. experimental infection of domestic pigeons with sporocysts excreted by experimentally infected northern goshawks reproduced the natural infectio ... | 2010 | 20945785 |
| high prevalence of sarcocystis calchasi sporocysts in european accipiter hawks. | the emerging sarcocystis calchasi induces a severe and lethal central nervous disease in its intermediate host, the domestic pigeon (columba livia f. domestica). experimental studies have identified the northern goshawk (accipiter g. gentilis) as final host. phylogenetically closely related european sparrowhawks (accipiter n. nisus) and wood pigeons (columba palumbus) have been found to harbor genetically closely related sarcocystis spp. however, data on the prevalence and potential interspecies ... | 2010 | 21074324 |
| high seroprevalence of antibodies to toxoplasma gondii in wild animals from portugal. | we report an investigation of antibodies to toxoplasma gondii in 52 wild birds and 20 wild mammals from northern and central areas of portugal by using the modified agglutination test. the birds comprised 26 common buzzards (buteo buteo), five tawny owls (strix aluco), four white storks (ceconia ceconia), three eurasian eagle owls (bubo bubo), three northern goshawks (accipiter gentilis), two booted eagles (hieraaetus pennatus), two common barn owls (tyto alba), two eurasian sparrowhawks (accipi ... | 2010 | 21104273 |
| territorial occupancy dynamics in a forest raptor community. | a markovian modeling approach was used to explore territorial interactions among three forest raptors coexisting in a forested natural area in southeast spain: the booted eagle (hieraaetus pennatus), the common buzzard (buteo buteo) and the northern goshawk (accipiter gentilis). using field data collected over a period of 12 years, 11 annual transition matrices were built, considering four occupancy states for each territory. the model describes transitional processes (colonization, abandonment, ... | 2010 | 21136084 |
| mesopredator release by an emergent superpredator: a natural experiment of predation in a three level guild. | intraguild predation (igp) is widespread but it is often neglected that guilds commonly include many layers of dominance within. this could obscure the effects of igp making unclear whether the intermediate or the bottom mesopredator will bear higher costs from the emergence of a new top predator. | 2010 | 21151912 |
| vulnerability of black grouse hens to goshawk predation: result of food supply or predation facilitation? | the plant cycle hypothesis says that poor-quality food affects both herbivorous voles (microtinae spp.) and grouse (tetraonidae spp.) in vole decline years, leading to increased foraging effort in female grouse and thus a higher risk of predation by the goshawk accipiter gentilis. poor-quality food (mainly the bilberry vaccinium myrtillus) for these herbivores is induced by seed masting failure in the previous year, when the bilberry is able to allocate resources for chemical defence (the mast d ... | 2011 | 21181416 |
| a first evaluation of the usefulness of feathers of nestling predatory birds for non-destructive biomonitoring of persistent organic pollutants. | in previous studies, feathers of adult predatory birds have been evaluated as valid non-destructive biomonitor matrices for persistent organic pollutants (pops). in this study, we assessed for the first time the usefulness of nestling raptor feathers for non-destructive biomonitoring of pops. for this purpose, we collected body feathers and blood of nestlings from three avian top predators from northern norway: northern goshawks (accipiter gentilis), white-tailed eagles (haliaeetus albicilla) an ... | 2011 | 21256594 |
| detection and molecular analysis of west nile virus infections in birds of prey in the eastern part of austria in 2008 and 2009. | the emergence of west nile virus (wnv) was expected in austria since the initial discovery of the infection in neighbouring hungary in 2003/2004. in 2008 six cases of west nile disease were diagnosed at the institute for veterinary disease control mödling, austrian agency for health and food safety (ages), involving five goshawks (accipiter gentilis) and one gyrfalcon (falco rusticolus), which were found dead in the eastern austrian federal states of lower austria, vienna and styria, respectivel ... | 2010 | 21276665 |
| use of raptors for biomonitoring of heavy metals: gender, age and tissue selection. | the concentrations of cadmium, mercury and lead were determined in liver, kidney and feathers of accipiter gentilis, buteo buteo and strix aluco. no significant differences in the concentrations of metals were observed in relation to either age or gender. cadmium levels in feathers and in kidney were significantly correlated (p < 0.01 or p < 0.05) in all species. in b. buteo, cadmium concentrations in feathers and in liver were also correlated (p < 0.01), as were the concentrations of lead in fe ... | 2011 | 21336862 |
| serum biochemistry values, plasma mineral levels, and whole blood heavy metal measurements in wild northern goshawks (accipiter gentilis). | serum chemistry panels and complete mineral and heavy metal screens were performed on blood samples from eight adult northern goshawks (accipiter gentilis) breeding in pennsylvania. serum chemistry panels were performed to determine the health status of each bird. biochemical values measured included serum glucose, sodium, potassium, chloride, magnesium, uric acid, creatine kinase, and aspartate transaminase. glucose, creatine kinase, and aspartate transaminase values were elevated when compared ... | 2010 | 21370646 |
| concentrations of retinol, 3,4-didehydroretinol, and retinyl esters in plasma of free-ranging birds of prey. | this study investigated vitamin a compounds in the plasma of healthy free-ranging central european raptors with different feeding strategies. plasma samples of nestlings of white-tailed sea eagle [white-tailed sea eagle (wtse), haliaeetus albicilla) (n = 32), osprey (pandion haliaetus) (n = 39), northern goshawk (accipiter gentilis) (n = 25), common buzzard (buteo buteo) (n = 31), and honey buzzard (pernis apivorus) (n = 18) and adults of wtse (n = 10), osprey (n = 31), and northern goshawk (n = ... | 2011 | 21895779 |
| causes of morbidity in wild raptor populations admitted at a wildlife rehabilitation centre in spain from 1995-2007: a long term retrospective study. | morbidity studies complement the understanding of hazards to raptors by identifying natural or anthropogenic factors. descriptive epidemiological studies of wildlife have become an important source of information about hazards to wildlife populations. on the other hand, data referenced to the overall wild population could provide a more accurate assessment of the potential impact of the morbidity/mortality causes in populations of wild birds. | 2011 | 21966362 |
| goshawk prey have more bacteria than non-prey. | 1. predators often prey on individuals that are sick or otherwise weakened. although previous studies have shown higher abundance of parasites in prey, whether prey have elevated loads of micro-organisms remains to be determined. 2. we quantified the abundance of bacteria and fungi on feathers of woodpigeons columba palumbus l., jays garrulus glandarius l. and blackbirds turdus merula l. that either fell prey to goshawks accipiter gentilis l. or were not depredated. 3. we found an almost three-f ... | 2012 | 22039986 |
| reference intervals for intraocular pressure measured by rebound tonometry in ten raptor species and factors affecting the intraocular pressure. | intraocular pressure (iop) was measured with the tonovet rebound tonometer in 10 raptor species, and possible factors affecting iop were investigated. a complete ophthalmic examination was performed, and iop was assessed in 2 positions, upright and dorsal recumbency, in 237 birds belonging to the families accipitridae, falconidae, strigidae, and tytonidae. mean iop values of healthy eyes were calculated for each species, and differences between families, species, age, sex, left and right eye, as ... | 2011 | 22216716 |
| blood plasma clinical-chemical parameters as biomarker endpoints for organohalogen contaminant exposure in norwegian raptor nestlings. | raptors are exposed to biomagnifying and toxic organohalogenated compounds (ohcs) such as organochlorines, brominated flame retardants and perfluorinated compounds. to investigate how ohc exposure may affect biochemical pathways we collected blood plasma from norwegian northern goshawk (n=56), golden eagle (n=12) and white-tailed eagle (n=36) nestlings during three consecutive breeding seasons. we found that blood plasma concentrations of calcium, sodium, creatinine, cholesterol, albumin, total ... | 2012 | 22445502 |
| selection of flight feathers from buteo buteo and accipiter gentilis for use in biomonitoring heavy metal contamination. | the concentrations of hg were determined in all primary flight feathers from 20 specimens of buteo buteo and 49 specimens of accipiter gentilis, which had died in various wildlife recovery centres in galicia (nw spain) between 2001 and 2009. the aim of the study was to standardize the feather or feathers that should be analyzed in each species to enable inter-individual comparison of the levels of contamination, taking into consideration any variability in the concentrations of hg caused by the ... | 2012 | 22481053 |
| predator fitness increases with selectivity for odd prey. | the fundamental currency of normative models of animal decision making is darwinian fitness. in foraging ecology, empirical studies typically assess foraging strategies by recording energy intake rates rather than realized reproductive performance. this study provides a rare empirical link, in a vertebrate predator-prey system, between a predator's foraging behavior and direct measures of its reproductive fitness. goshawks accipiter gentilis selectively kill rare color variants of their principa ... | 2012 | 22503502 |
| impact of climate change and prey abundance on nesting success of a top predator, the goshawk. | contemporary research has documented a large number of shifts in spring phenology and changes in distribution range although the average spring temperatures have increased by only 0.3-0.6 °c over the past 100 years. generally, earlier breeding birds have larger clutch sizes, and the advancing spring could thus potentially increase breeding success. shifts in spring phenology can, however, be crucial for bird reproduction, and mistiming the breeding event may even have negative consequences for p ... | 2013 | 22791186 |
| molecular identification of traces from the white-tailed sea eagle. | over the preceeding decades, after periods of dramatic decline and extinction in many parts of europe, the white-tailed sea eagle (haliaeetus albicilla) has re-colonized traditional breeding areas. however, this large apex predator remains threatened, not only by the bioaccumulation of environmental pollutants, but also by targeted poisoning and poaching. in connection with a forensic case, a novel pcr assay was developed for the sensitive and specific detection of sea eagle dna traces in questi ... | 2013 | 22926772 |
| 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 |
| west nile virus infections in greece: an update. | approximately 2 years have passed since the detection of the first human case of west nile virus (wnv) infection in greece, which was the starting signal of a large outbreak in 2010, followed by a second one in 2011. more than 250 neuroinvasive disease cases with 15% fatality were observed during the two wnv seasons. wnv lineage 2 sequences were obtained from blood donors, culex mosquitoes, wild birds and sentinel chickens. the greek wnv strain shows high genetic relatedness to the goshawk-hunga ... | 2012 | 22943398 |