| a case of anisakis sp. infection in a brown bear from alaska. | | 1971 | 5107111 |
| brown/grizzly bear mouth cultures in alaska. | | 1983 | 6869695 |
| serologic survey for trichinella spp. in grizzly bears from alaska. | blood was collected from 878 grizzly bears (ursus arctos) in seven geographic areas of alaska from 1973 to 1987. an enzyme-linked immunosorbent assay procedure was used to test sera for evidence of exposure to trichinella spp. serum antibody prevalence ranged from 5% (10 positive of 196 tested) in the southern region of the state to 83% (355 of 430 tested) in the northern region. these major discrepancies may be a result of differing food habits of bears in the major geographic areas. prevalence ... | 1997 | 9249692 |
| taenia arctos n. sp. (cestoda: cyclophyllidea: taeniidae) from its definitive (brown bear ursus arctos linnaeus) and intermediate (moose/elk alces spp.) hosts. | taenia arctos n. sp. (cestoda: cyclophyllidea: taeniidae) is described from the brown bear ursus arctos linnaeus (definitive host) and moose/elk alces spp. (intermediate hosts) from finland (type-locality) and alaska, usa. the independent status of the new species and the conspecificity of its adults and metacestodes have been recently confirmed by the mtdna sequence data of lavikainen et al. (2011; parasitology international, 60, 289-295). special reference is given to morphological differences ... | 2011 | 22002024 |
| consumption of salmon by alaskan brown bears: a trade-off between nutritional requirements and the risk of infanticide? | the risk of infanticide may alter foraging decisions made by females, which otherwise would have been based on nutritional requirements and forage quality and availability. in systems where meat resources are spatially aggregated in late summer and fall, female brown bears (ursus arctos) would be faced with a trade-off situation. the need of reproductive females to accumulate adequate fat stores would likely result in a decision to frequent salmon streams and consume the protein- and lipid-rich ... | 2004 | 14673639 |
| autochthonous and imported trichinella isolates in germany. | the study of trichinella isolates from wildlife in germany revealed the presence of trichinella spiralis and trichinella britovi in wild boars and foxes. t spiralis was detected in meat products imported from spain, which is one of the two endemic areas of domestic trichinellosis in the european union: it was also detected in meat from a grizzly bear marketed in alaska, and trichinella nativa was detected in a polar bear from the berlin zoo. these results stress the importance of examining for t ... | 2000 | 10622607 |
| genetic relationships of grizzly bears (ursus arctos) in the prudhoe bay region of alaska: inference from microsatellite dna, mitochondrial dna, and field observations. | grizzly bears are abundant in the region of the prudhoe bay oil fields in northern alaska. we used field observations and molecular genetic data to identify parent-offspring and sibling relationships among bears in this region. we determined genotypes at 14 microsatellite dna loci and the cytochrome b gene of mitochondrial dna (mtdna) for 36 bears. we identified 17 possible mother-offspring pairs and 8 possible father-offspring pairs. this includes verification of the relationships of 14 mother- ... | 1999 | 10589512 |
| serological survey of selected canine viral pathogens and zoonoses in grizzly bears (ursus arctos horribilis) and black bears (ursus americanus) from alaska. | between 1988 and 1991, 644 serum samples were collected from 480 grizzly bears (ursus arctos horribilis) and 40 black bears (ursus americanus) from alaska, united states of america, and were tested for selected canine viral infections and zoonoses. antibody prevalence in grizzly bears was 0% for parvovirus, 8.3% (40/480) for distemper, 14% (68/480) for infectious hepatitis, 16.5% (79/480) for brucellosis, 19% (93/480) for tularaemia and 47% (225/478) for trichinellosis. in black bears, prevalenc ... | 1998 | 9850547 |
| serologic survey for toxoplasma gondii in grizzly bears from alaska. | blood samples were collected from 892 grizzly bears (ursus arctos) in alaska (usa) from 1973 to 1987. sera were tested for evidence of exposure to toxoplasma gondii by means of the modified agglutination test. two hundred twenty sera (25%) had titers > or = 25, the minimum threshold titer. six hundred seventy-two sera (75%) had titers < 25. antibody prevalence ranged from 9% (18 positive of 196 tested) in southern areas to 37% (162 of 433 tested) in northern areas. there was no readily apparent ... | 1997 | 9131557 |
| phylogeography of brown bears (ursus arctos) of alaska and paraphyly within the ursidae. | complete nucleotide sequences of the mitochondrial cytochrome b, trna(prolime), and trna(threonine) genes were described for 166 brown bears (ursus arctos) from 10 geographic regions of alaska to describe natural genetic variation, construct a molecular phylogeny, and evaluate classical taxonomies. dna sequences of brown bears were compared to homologous sequences of the polar bear (maritimus) and of the sun bear (helarctos malayanus), which was used as an outgroup. parsimony and neighbor-joinin ... | 1996 | 8744762 |
| serologic survey of toxoplasma gondii in grizzly bears (ursus arctos) and black bears (ursus americanus), from alaska, 1988 to 1991. | we tested 644 serum samples from 480 grizzly bears and 40 black bears from alaska (usa), collected between 1988 and 1991, for toxoplasma gondii antibodies, using a commercially available latex agglutination test (lat). a titer > or = 64 was considered positive. serum antibody prevalence for t. gondii in grizzly bears (ursus arctos) was 18% (87 of 480). prevalence ranged from 9% (seven of 77) on kodiak island to 28% (15 of 54) in northern alaska. prevalence was directly correlated to age. no griz ... | 1995 | 8592377 |
| trichinosis associated with meat from a grizzly bear--alaska. | | 1981 | 6789058 |
| serologic evidence of arbovirus infections in humans and wild animals in alaska. | blood samples were collected from humans and several species of free-ranging wild animals in alaska. sera were tested for antibody to jamestown canyon (jc), snowshoe hare (ssh), northway (nor), klamath (kla), sakhalin (sak), great island (gi), and silverwater (sil) virus. jc antibody was found in 54% of 121 human, 89% of 97 bison (bison bison), 51% of 84 dall sheep (ovis dalli), 43% of 68 snowshoe hare (lepus americanus), and 3% of 33 arctic fox (alopex lagopus) sera. ssh antibody was found in 4 ... | 1983 | 6644915 |
| serologic survey for infectious canine hepatitis virus in grizzly bears (ursus arctos) from alaska, 1973 to 1987. | serum antibody prevalence of infectious canine hepatitis virus was 12% (90 of 725) for grizzly bears (ursus arctos) from alaska (usa) during the period 1973 to 1987. prevalence was highest on kodiak island at 29% (37 of 127). prevalence of exposure at individual collection areas did not change significantly over time. there were no significant sex-specific differences in prevalence. prevalence was directly related to age, but it was 0% for bears less than 2-yr-old. young bears which are exposed ... | 1989 | 2554000 |
| further observations on rangiferine brucellosis in alaskan carnivores. | antibodies against rangiferine brucellosis, brucella suis type 4, are commonly found in the serum of various domestic and wild alaskian carnivores which feed on caribou, rangifer tarandus granti, arctic alaska. sled dogs from five native villages on the range of the artic caribou herd, but not from two villages on the the range of the porcupine caribou herd, are commonly infected. wolves (canis lupus) and red foxes (vulpes fulva) are less commonly infected. about 90% of the grizzly bears (ursus ... | 1975 | 1113440 |
| despotism and risk of infanticide influence grizzly bear den-site selection. | given documented social dominance and intraspecific predation in bear populations, the ideal despotic distribution model and sex hypothesis of sexual segregation predict adult female grizzly bears (ursus arctos) will avoid areas occupied by adult males to reduce risk of infanticide. under ideal despotic distribution, juveniles should similarly avoid adult males to reduce predation risk. den-site selection and use is an important component of grizzly bear ecology and may be influenced by multiple ... | 2011 | 21935378 |
| molecular identification of taenia spp. in wolves (canis lupus), brown bears (ursus arctos) and cervids from north europe and alaska. | taenia tapeworms of finnish and swedish wolves (canis lupus) and finnish brown bears (ursus arctos), and muscle cysticerci of svalbard reindeer (rangifer tarandus platyrhynchus), alaskan grant's caribou (rangifer tarandus granti) and alaskan moose (alces americanus) were identified on the basis of the nucleotide sequence of a 396bp region of the mitochondrial cytochrome c oxidase subunit 1 gene. two species were found from wolves: taenia hydatigena and taenia krabbei. the cysticerci of reindeer, ... | 2011 | 21571090 |
| geographic pattern of serum antibody prevalence for brucella spp. in caribou, grizzly bears, and wolves from alaska, 1975-1998. | blood samples were collected from 2,635 caribou (rangifer tarandus), 1,238 grizzly bears (ursus arctos), and 930 wolves (canis lupus) from throughout mainland alaska during 1975-98. sera were tested for evidence of exposure to brucella spp. serum antibody prevalences were highest in the northwestern region of the state. in any specific area, antibody prevalences for caribou and wolves were of a similar magnitude, whereas antibody prevalence for bears in these same areas were two to three times h ... | 2006 | 17092888 |
| sexual dimorphism, reproductive strategy, and human activities determine resource use by brown bears. | despite significant sexual dimorphism and differing reproductive strategies in carnivores, sexual segregation is rarely studied and is often overlooked in the management of wild populations. potential nutritional constraints imposed by sexual dimorphism and differing reproductive strategies between the sexes have important implications, particularly when combined with differential effects of human activities on sex and age classes. we examined the effects of sexual dimorphism, reproductive strat ... | 2006 | 17089671 |
| predator avoidance during reproduction: diel movements by spawning sockeye salmon between stream and lake habitats. | daily movements of mobile organisms between habitats in response to changing trade-offs between predation risk and foraging gains are well established; however, less in known about whether similar tactics are used during reproduction, a time period when many organisms are particularly vulnerable to predators. we investigated the reproductive behaviour of adult sockeye salmon (oncorhynchus nerka) and the activity of their principal predator, brown bears (ursus arctos), on streams in south-western ... | 2014 | 24702169 |
| genomic evidence of geographically widespread effect of gene flow from polar bears into brown bears. | polar bears are an arctic, marine adapted species that is closely related to brown bears. genome analyses have shown that polar bears are distinct and genetically homogeneous in comparison to brown bears. however, these analyses have also revealed a remarkable episode of polar bear gene flow into the population of brown bears that colonized the admiralty, baranof and chichagof islands (abc islands) of alaska. here, we present an analysis of data from a large panel of polar bear and brown bear ge ... | 2015 | 25490862 |
| removal of lipid from serum increases coherence between brucellosis rapid agglutination test and enzyme-linked immunosorbent assay in bears in alaska, usa. | in cases of chronic brucella spp. infection, results of the rose bengal plate test (rbpt) and indirect enzyme-linked immunosorbent assay (elisa) should be coherent, as reported in controlled conditions in the literature. we compared rbpt and elisa results in 58 alaska grizzly bears ( ursus arctos horribilis), eight kodiak brown bears ( ursus arctos middendorffi), and six alaska peninsula brown bears ( ursus arctos gyas). of the 72 bears tested, 42 (58%) were elisa positive and 53 (73%) were rbpt ... | 2016 | 27458833 |
| environmental dna from residual saliva for efficient noninvasive genetic monitoring of brown bears (ursus arctos). | noninvasive genetic sampling is an important tool in wildlife ecology and management, typically relying on hair snaring or scat sampling techniques, but hair snaring is labor and cost intensive, and scats yield relatively low quality dna. new approaches utilizing environmental dna (edna) may provide supplementary, cost-effective tools for noninvasive genetic sampling. we tested whether edna from residual saliva on partially-consumed pacific salmon (oncorhynchus spp.) carcasses might yield suitab ... | 2016 | 27828988 |
| size selectivity of predation by brown bears depends on the density of their sockeye salmon prey. | can variation in prey density drive changes in the intensity or direction of selective predation in natural systems? despite ample evidence of density-dependent selection, the influence of prey density on predatory selection patterns has seldom been investigated empirically. we used 20 years of field data on brown bears (ursus arctos) foraging on sockeye salmon (oncorhynchus nerka) in alaska, to test the hypothesis that salmon density affects the strength of size-selective predation. measurement ... | 2013 | 23594549 |
| can intense predation by bears exert a depensatory effect on recruitment in a pacific salmon population? | it has long been recognized that, as populations increase in density, ecological processes affecting growth and survival reduce per capita recruitment in the next generation. in contrast to the evidence for such "compensatory" density dependence, the alternative "depensatory" process (reduced per capita recruitment at low density) has proven more difficult to demonstrate in the field. to test for such depensation, we measured the spawner-recruit relationship over five decades for a sockeye salmo ... | 2014 | 25154755 |
| tool-use in the brown bear (ursus arctos). | this is the first report of tool-using behaviour in a wild brown bear (ursus arctos). whereas the use of tools is comparatively common among primates and has also been documented in several species of birds, fishes and invertebrates, tool-using behaviours have so far been observed in only four species of non-primate mammal. the observation was made and photographed while studying the behaviour of a subadult brown bear in south-eastern alaska. the animal repeatedly picked up barnacle-encrusted ro ... | 2012 | 22367156 |
| gene flow between insular, coastal and interior populations of brown bears in alaska. | the brown bears of coastal alaska have been recently regarded as comprising from one to three distinct genetic groups. we sampled brown bears from each of the regions for which hypotheses of genetic uniqueness have been made, including the bears of the kodiak archipelago and the bears of admiralty, baranof and chichagof (abc) islands in southeast alaska. these samples were analysed with a suite of nuclear microsatellite markers. the 'big brown bears' of coastal alaska were found to be part of th ... | 1998 | 9787441 |
| using grizzly bears to assess harvest-ecosystem tradeoffs in salmon fisheries. | implementation of ecosystem-based fisheries management (ebfm) requires a clear conceptual and quantitative framework for assessing how different harvest options can modify benefits to ecosystem and human beneficiaries. we address this social-ecological need for pacific salmon fisheries, which are economically valuable but intercept much of the annual pulse of nutrient subsidies that salmon provide to terrestrial and aquatic food webs. we used grizzly bears, vectors of salmon nutrients and animal ... | 2012 | 22505845 |