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 ...19836338824
don't put all your eggs in one nest: spread them and cut time at many egg-laying animals, some females spread their clutch among several nests. the fitness effects of this reproductive tactic are obscure. using mathematical modeling and field observations, we analyze an unexplored benefit of egg spreading in brood parasitic and other breeding systems: reduced time at risk for offspring. if a clutch takes many days to lay until incubation and embryo development starts after the last egg, by spreading her eggs a parasitic female can reduce offspring time in ...201222854078
competition between freshwater fish and goldeneyes bucephala clangula (l.) for common prey.results of a descriptive field study showed that goldeneyes preferred lakes without fish to those with fish. field experiments were carried out in order to investigate whether or not this preference could be ascribed to a higher food supply in the lakes devoid of fish, as goldeneyes and some freshwater fish (perch and roach in the studied lakes) to some extent feed on the same kinds of prey. changes in the abundance of prey common to fish and goldeneyes and the use by goldeneyes of lakes after e ...197928310363
generalist predator, cyclic voles and cavity nests: testing the alternative prey hypothesis.the alternative prey hypothesis (aph) states that when the density of the main prey declines, generalist predators switch to alternative prey and vice versa, meaning that predation pressure on the alternative prey should be negatively correlated with the density of the main prey. we tested the aph in a system comprising one generalist predator (pine marten, martes martes), cyclic main prey (microtine voles, microtus agrestis and myodes glareolus) and alternative prey (cavity nests of common gold ...201627665542
the body size-dependent diet composition of north american sea ducks in winter.daily food requirements scale with body mass and activity in animals. while small species of birds have higher mass-specific field metabolic rates than larger species, larger species have higher absolute energy costs. under energy balance, we thus expect the small species to have a higher energy value diet. also the weight and time constraints for flighted and diurnal foragers should set a maximum to the amount of prey items taken in one meal and to the daily number of meals, respectively. furth ...201323755266
nest predation and the evolution of conspecific brood parasitism: from risk spreading to risk assessment.conspecific brood parasitism (cbp) is a taxonomically widespread reproductive tactic. one of the earliest hypotheses put forward to explain the evolution of cbp was "risk spreading"; that is, by laying eggs in more than one nest, parasites may increase the likelihood that at least one offspring will survive to independence. however, the risk spreading hypothesis, based on the assumptions of random nest predation and random selection of target nests by parasites, was theoretically refuted soon af ...200717206588
[first record of species dicranotaenia synsacculata macko, 1988 (cestoda, hymenolepididae) of the goldeneye bucephala clangula (linneus, 1758) in poland].during parasitological studies of 32 specimens of the goldeneye bucephala clangula l., twenty seven cestode specimens were found. four of them, isolated from the jejunum of two young female hosts, were determinated as dicranotaenia synsacculata macko, 1988. we based on the shape of cirrus fused with sacculus accessorius internus, shape and size of scolex and other organs. this is the first record of this species in poland.201021179669
female goldeneye ducks (bucephala clangula) do not discriminate among male precopulatory display patterns.female goldeneyes remain motionless on the surface of the water while single males circle them performing a series of highly stereotyped displays. after performing between eight and 90 of these displays the male either copulates or attempts to copulate with the female. however, females allow only 58% of males to mount them, while rejecting 42%. we have examined 804 of these precopulatory sequences containing 11,841 actions in an effort to determine why females find some display sequences of male ...201323516410
mechanisms of density dependence in ducks: importance of space and per capita food.the growth rate of populations usually varies over time, often in a density-dependent manner. despite the large amount of literature on density dependence, relatively little is known of the mechanisms underlying the density-dependent processes affecting populations, especially per capita natality. we performed a 20-year study on the density dependence of brood production in two duck species differing in the stability of habitat use. our study was conducted in a boreal watershed in southern finla ...201525398723
morphometrical and ecological analysis of nematodes of the family capillariidae (neveu-lemaire, 1936) in wild ducks (anatinae) from the north-western poland.west pomerania is located on the migratory route of many species of birds. among them are many representatives of wild duck species (subfamily anatinae), which are often the primary hosts of many helminths due to the fact of living in two different environments: terrestrial and aquatic. however, until the end of the 90s, research conducted in poland on the helminth fauna of wild birds, including nematodes of the family capillariidae, did not include the north-western region of the country. these ...201324791347
shared and unshared parental investment in the precocial goldeneye (aves: anatidae)lazarus & inglis (anim. behav., 1986, 34, 1791-1804) introduced a model of the influence of brood size on the optimal level of parental investment and parent-offspring conflict and drew a distinction between shared and unshared types of parental investment. with respect to this division, we measured the parental costs in the goldeneye, bucephala clangula, a precocial species with uniparental female care, in terms of time spent in vigilance and intraspecific aggression. we also compared levels of ...19989480698
metal contents in liver tissues of non-fledged goldeneye, bucephala clangula, ducklings: a comparison between samples from acidic, circumneutral, and limed lakes in south sweden.the risk of increased exposure to metals for a vertebrate predator foraging on aquatic insects in acidified lakes was investigated through analyses of the content of al, as, ca, cd, cu, fe, hg, mn, pb, ru, se, and zn in the liver tissue of 42 non-fledged goldeneye, bucephala clangula, ducklings from acidic, circumneutral, and limed lakes in south sweden. no indications of significantly different concentrations in samples from acidic lakes in comparison with circumneutral lakes were detected for ...20062923494
ducks change wintering patterns due to changing climate in the important wintering waters of the odra river estuary.some species of birds react to climate change by reducing the distance they travel during migration. the odra river estuary in the baltic sea is important for wintering waterfowl and is where we investigated how waterbirds respond to freezing surface waters. the most abundant birds here comprise two ecological groups: bottom-feeders and piscivores. numbers of all bottom-feeders, but not piscivores, were negatively correlated with the presence of ice. with ongoing global warming, this area is inc ...201728785517
ability to assess nest predation risk in secondary hole-nesting birds: an experimental study.because nest predation is the major source of nesting mortality in birds, site-specific predation risk may play an important role in determining birds' ability to select nest sites that reduce predation risk. this possibility has not been adequately tested. here we report on 5-year experiments by which we studied, independently from birds' earlier experience with specific nest boxes, both the selection and predation risk of nest sites in the common goldeneye (bucephala clangula). new, previously ...200128547618
nematodes in the mallard (anas platyrhynchos linnaeus, 1758) and the common goldeneye (bucephala clangula linnaeus, 1758) (anatidae) from northern europe.there are first data on nematodes of anas platyrhynchos linnaeus, 1758 (mallard) and bucephala clangula linnaeus, 1758 (common goldeneye) from northern europe (ladoga lake region). the ducks were found to be infected with nine nematode species. a. platyrhynchos hosted eight nematode species and b. clangula was host to four nematode species. all species except capillaria anatis were found in the region for the first time. nematodes amidostomum acutum, streptocara crassicauda, and tetrameres fissi ...201526323580
prevalence and subtypes of influenza a viruses in wild waterfowl in norway 2006-2007.the prevalence of influenza a virus infection, and the distribution of different subtypes of the virus, were studied in 1529 ducks and 1213 gulls shot during ordinary hunting from august to december in two consecutive years, 2006 and 2007, in norway. the study was based on molecular screening of cloacal and tracheal swabs, using a pan-influenza a rt-pcr. samples found to be positive for influenza a virus were screened for the h5 subtype, using a h5 specific rt-pcr, and, if negative, further subt ...201020426812
[biological and ecological background of nematode fauna structure formation in the alimentary tracts of wild anatinae ducks in north-western poland].the study involved a total of 250 wild ducks representing 17 species of three ecologically different tribes: the anatini (113 individuals), the aythyini (71), and the mergini (66). the ducks, obtained mainly from fishermen and hunters, were examined for the presence of parasites, using the generally accepted methods. analyses of nematode assemblage structure were conducted with methods described in the literature. in addition, significance of differences in intensity of infestation was determine ...200818664105
biostrome communities and mercury and selenium bioaccumulation in the great salt lake (utah, usa).the great salt lake has a salinity near 150g/l and is habitat for over 200 species of migratory birds. the diet of many of these birds is dependent on the food web of carbonaceous biostromes (stromatolites) that cover 260km(2) of the lake's littoral zone. we investigated the biostrome community to understand their production processes and to assess whether they are a potential vector for bioconcentration of high mercury and selenium levels in the lake. the periphyton community of the biostromes ...201121835437
sarcocystis sp. from the goldeneye (bucephala clangula) and the mallard (anas platyrhynchos): cyst morphology and ribosomal dna light microscopy, cysts of sarcocystis sp. (cyst type i) from the goldeneye (bucephala clangula) seemed filamentous with a smooth and thin (<1 microm) cyst wall. ultrastructurally, the cyst wall surface was irregular with minute undulations of the primary cyst wall. these sarcocysts had type-1 cyst wall. cystozoites were banana-shaped and measured 7.0-8.5 microm in length. by light microscopy, cysts of sarcocystis sp. (cyst type ii) from the mallard (anas platyrhynchos) were ribbon-shaped, ve ...200818084777
selenium accumulation in sea ducks wintering at lake ontario.numbers of wintering sea ducks, including buffleheads (bucephala albeola; buff), common goldeneyes (bucephala clangula; cogo), and long-tailed ducks (clangula hyemalis; ltdu), increased substantially at lake ontario after dreissenid mussels (dreissena bugensis and d. polymorpha) colonized the great lakes. invertebrates, including dreissenid mussels, are major diving duck prey items that can transfer some trace elements, such as selenium (se) to higher trophic levels. se can be problematic for wa ...201019653029
[aythya fuligula--new host for retinometra pittalugai lopez-neyra, 1932 (cestoda, hymenolepididae) recorded in poland for the first time].during standard parasitological studies of the tufted duck aythya fuligula (linnaeus, 1758), obtained from fishermen from west pomerania, three cestode specimens were found in the jejunum of hosts. they were determined as retinometra pittalugai (lopez-neyra, 1932) on the basis of the cirrus's size, shape of stylet and rostellar hooks. this is the first record of this species in poland, since this parasite was earlier recorded only in anas platyrhynchos f. dom., aythya marila, a. ferina and bucep ...200819338226
trace element concentrations in wintering waterfowl from the great salt lake, utah.the great salt lake (gsl) is an important region for millions of migratory waterbirds. however, high concentrations of some trace elements, including hg and se, have been detected within the gsl, and baseline ecotoxicological data are lacking for avian species in this system. we collected common goldeneye (bucephala clangula), northern shoveler (anas clypeata), and green-winged teal (a. crecca) from the gsl during the winters of 2004-2005 and 2005-2006 to evaluate sources of variation in liver t ...200918560923
avian influenza virus screening in wild waterfowl in norway, 2005.the prevalence of influenza a virus infection, and the distribution of different subtypes of the virus, were studied in 604 geese and ducks shot during ordinary hunting 2005. the study was based upon molecular screening of cloacal swabs taken by the hunters. the sampling included the following species: greylag (anser anser), mallard (anas platyrhynchos), wigeon (anas penelope), teal (anas crecca), goosander (mergus merganser), tufted duck (aythya fuligula), common scoter (melanitta nigra), golde ...200717494599
an outbreak of fowl cholera in waterfowl on the chesapeake outbreak of fowl cholera (pasteurella multocida infection) occurred in waterfowl wintering on the chesapeake bay during february to march 1970. losses were primarily confined to sea ducks: oldsquaws (clangula hyemalis), white-winged scoters (melanitta deglandi), goldeneyes (bucephala clangula), and buffleheads (bucephala albeola).197016512146
accumulation in and effects of lead and cadmium on waterfowl and passerines in northern idaho.waterfowl and passerines in northern idaho in 1987 had high levels of lead in their blood and tissues that originated primarily from mining and smelting activities. four canada geese (branta canadensis) and one common goldeneye (bucephala clangula) found dead contained 8 to 38 microg/g (wet mass) of lead in their livers. these levels exceed the lower lethal limit of 5 microg/g in experimental birds. two of the canada geese (one each from the contaminated and reference areas) died with ingested l ...199515091521
efficiency gain from auxiliary data requiring additional nuisance a mark-recapture study of an animal population, live-recapture information may be supplemented by resightings from marked animals obtained throughout the period of the study and the two types of data analyzed simultaneously. the resighting data can only contribute to estimates of survival probability if they are jointly modeled with the live-recapture data and require the inclusion of additional nuisance parameters. we show that, under quite general conditions, estimates of the original param ...200111414584
host-parasite relatedness shown by protein fingerprinting in a brood parasitic bird.brood parasitism as an alternative female breeding tactic is particularly common in ducks, where hosts often receive eggs laid by parasitic females of the same species and raise their offspring. herein, we test several aspects of a kin selection explanation for this phenomenon in goldeneye ducks (bucephala clangula) by using techniques of egg albumen sampling and statistical bandsharing analysis based on resampling. we find that host and primary parasite are indeed often related, with mean r = 0 ...200011050150
runting of ducklings associated with cochlosoma anatis infection.ducklings, especially common goldeneye (bucephala clangula), experiencing poor weight gain and delayed development were reported from a waterfowl park during june and july of 1990. runting was first noticed between days 5 and 10 post-hatch in the "brooder" building, and although ducklings appeared active and were feeding, they developed at a slower rate than other members of their clutch. many ultimately died of emaciation and gram-negative bacterial septicemia. necropsies of affected ducklings ...19968713032
morphological features of cloacotaenia megalops (nitzsch in creplin, 1829) (cestoda, hymenolepididae) from different hosts.the tapeworm species cloacotaenia megalops (nitzsch in creplin, 1829) is characterized by a very specific morphology. a particularly distinct feature is a large almost square scolex in which four fleshy suction cups are embedded and a rudimentary rostellum. during standard studies of wild duck cestode fauna in northwestern poland, some morphological differences were observed among specimens, mainly in the shape of scolices and hermaphroditic proglottids of c. megalops isolated from different bir ...201121634232
profilicollis botulus (van cleave, 1916) from diving ducks and shore crabs of british columbia.adults of profilicollis botulus were found in 6 species of diving ducks in british columbia including 3 new hosts: common goldeneye, bucephala clangula (l.); barrow's goldeneye, b. islandica (gmelin); and greater scaup, aythya marila (l.). the identification of the species was verified by the examination of co-types and specimens from eider ducks, somateria mollissima (l.), from scotland and oldsquaw, clangula hyemalis (l.), from new brunswick. cystacanths from the hairy shore crab, hemigrapsus ...19892918442
assessment of doses to game animals in finland.a study was carried out to assess the dose rates to game animals in finland affected by the radioactive caesium deposition that occurred after the accident at the chernobyl nuclear power plant in ukraine in 1986. the aim of this assessment was to obtain new information on the dose rates to mammals and birds under finnish conditions. dose rates were calculated using the erica assessment tool developed within the ec 6th framework programme. the input data consisted of measured activity concentrati ...201323395135
cloacotaenia megalops (nitzsch in creplin, 1829) (cestoda, hymenolepididae) in wild ducks in western pomerania, poland.cloacotaenia megalops (nitzsch in creplin, 1892) is a polyxenic and cosmopolitan tapeworm from the family hymenolepididae. its generic name derives from their typical location (cloaca), and the typical final hosts which are birds typically associated with water and marsh environments: anseriformes, galliformes and gruiformes. in poland, the presence of c. megalops has been observed so far in 16 species of ducks from the baltic coast, the mazurian lake district, wielkopolsko-kujawska lowland, maz ...201121682099
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