Publications

the fringed tapeworm (thysanosoma actinioides) as a parasite of the rocky mountain elk in yellowstone national park.		1969	5816103
the rocky mountain elk as a reservoir host for parasites of domestic animals in western montana.		1969	5817794
comparative survival of indicator bacteria and enteric pathogens in well water.	the comparative survival of various fecal indicator bacteria and enteric pathogens was studied in a stable well water supply by using membrane chambers. there was more variation in the 29 coliform cultures and they died more rapidly, as a group, than the 20 enterococcus cultures that were examined. the comparative survival of the organisms tested follows: aeromonas sp. > the shigellae (shigella flexneri, s. sonnei, and s. dysenteriae) > fecal streptococci > coliforms = some salmonellae (salmonel ...	1974	4598219
distribution and seasonal prevalence of bovine lungworms in selected areas in western montana.	in a survey (oct, 1967, through aug, 1969) of the distribution and seasonal prevalence of bovine lungworms in beef herds in 3 western montana counties (park, gallatin, and ravalli), infected cattle were detected in 27 of 35 herds. results of 2,125 fecal examinations indicated that 7.8% of all cattle were infected with dictyocaulus viviparus. lungworms were found in 6.6% of 1,038 calves (less than 12 months old), 11.5% of 755 yearlings (1 to 2 years old), and 3.3% of 332 cows (more than 2 years o ...	1975	123141
observations on epizootiology and distribution of elaeophora schneideri in montana ruminants.	seventy-four moose, 111 elk, 20 mule deer, 8 white-tailed deer, 26 prong-horn antelope, 42 domestic sheep and 3 bighorn sheep from montana or northwestern wyoming were examined post-mortem for evidence of elaeophora schneideri infection in 1973-74. fifteen percent of the mule deer and four percent of the moose were positive for adult arterial worms. this constitutes the first report of e. schneideri in mule deer in montana. no gross signs of blindness or other neurologic disorder were evident in ...	1975	127848
sarcocystis in free-ranging herbivores on the national bison range.	heart, esophagus, diaphragm and skeletal muscle obtained from various herbivores on the national bison range were examined grossly for sarcocystis. sarcocystis was found in 81, 50, 50, and 13% of the mule deer, (odocoileus hemionus), white-tailed deer (o. virginianus), elk (cervus elaphus), and bison (bison bison), respectively.	1979	110949
coyote as a final host for sarcocystis species of goats, sheep, cattle, elk, bison, and moose in montana.	tissues (1 kg) from sheep, goats, cattle, moose, bison, or elk naturally infected with sarcocystis species were fed to one to four sarcocystis-free coyotes and the number of sporocysts in feces and intestines were counted. all 12 coyotes fed naturally infected tissues shed sarcocystis in feces, with a prepatent period of 9 to 15 days. the four coyotes fed infected beef had 15, 25, 113, and 201 million sporocysts in their feces and intestines. the coyotes fed elk, moose, or bison had 2.5, 15, and ...	1980	6778270
isolation of encysted toxoplasma gondii from musculature of moose and pronghorn in montana.	pieces of skeletal muscle from 43 mule deer, 34 elk, 4 white-tailed deer, 21 pronghorn, 7 moose, and 2 bison were examined for toxoplasma infection, by the acid-pepsin digestion technique. toxoplasma gondii was isolated from 1 moose and 1 pronghorn. the isolated strains of t gondii were of low virulence to mice.	1981	7224306
fluoride toxicosis in wild ungulates.	to compare the occurrence of chronic fluoride toxicosis in wild and domestic animals in selected areas of utah, idaho, montana, and wyoming, deer, elk, and bison bones and teeth were collected for evaluation. vegetation and drinking water samples also were collected, so that potential sources of fluoride could be evaluated. deer, elk, and bison were found to be susceptible to the adverse effects of ingestion of excessive amounts of fluoride. teeth and bones were primarily affected with character ...	1984	6511570
serologic prevalence of toxoplasmosis in cattle, sheep, goats, pigs, bison, and elk in montana.	serum samples from 2,539 cattle, 649 sheep, 123 goats, 413 pigs, 93 bison, and 56 elk from montana were examined for antibody to toxoplasma gondii in the sabin-feldman dye test or the modified agglutination test (mat). cattle, bison, and elk serum samples were treated with 0.2 m-mercaptoethanol before examination in mat. in the dye test, 13.2% of sheep, 5.0% of pigs, and 22.7% of goats had antibody at a dilution of greater than or equal to 1:16. in the mat, 3.2% of cattle, 3.1% of bison, and non ...	1985	3997650
survey of free-ranging elk from wyoming and montana for selected pathogens.	from december 1991 through january 1995, a disease survey was conducted on herds of free-ranging, hunter-killed elk (cervus elaphus nelsoni) from three areas in proximity to yellowstone national park (ynp), wyoming (usa), after tuberculosis caused by mycobacterium bovis was discovered in a captive herd of elk in the area. complete or partial sets of specimens from 289 elk collected between december 1991 and january 1993 were examined histologically; no mycobacterial lesions were observed. lesion ...	1997	9131561
restriction fragment length polymorphism analysis of mycobacterium bovis isolates from captive and free-ranging animals.	mycobacterium bovis isolates from cattle, captive elk, and free-ranging mule deer and coyotes were examined by restriction fragment length polymorphism (rflp) analysis. dna extracted from each isolate was digested with restriction endonucleases alui and pvuii. dna probes used for southern hybridizations were a 37-base oligonucleotide and a 123-base-pair sequence specific for the insertion sequence is6110 and a plasmid, ptbn12, which contains a polymorphic gc-rich repetitive sequence present in s ...	1997	9376427
fascioloidiasis in game-ranched elk from montana.	the distribution of fascioloides magna in game-ranched elk and the potential for spread of the parasite through movement of infected animals was examined in montana (usa). fecal samples (n = 448) collected from captive elk on 29 game ranches were examined for eggs of f. magna by fecal sedimentation. eggs were detected in elk on 5 ranches. this suggests that f. magna has been translocated by infected game-ranched elk. the wide distribution of snail intermediate hosts for f. magna in montana indic ...	1997	9391977
short- and longer-term effects of fire and herbivory on sagebrush communities in south-central montana.	to better understand the role of herbivory and fire as potential disturbance processes in sagebrush communities, we examined responses of a grazing ungulate, elk (cervus elaphus), following prescribed burning of sagebrush (artemisia tridentata ssp. vaseyana) in south-central montana (usa.) with concurrent monitoring of changes in plant production, nutritional quality, and community diversity from 1989-1999. burning transformed low-diversity, sagebrush-dominated communities into high-diversity, g ...	2006	16736297
brucellosis in elk of eastern idaho.	brucellosis occurs in free-ranging elk (cervus elaphus) and bison (bison bison) in the greater yellowstone area, which includes portions of idaho, wyoming, and montana. brucella abortus was first detected in elk in idaho in 1998, and from 1998 to 2002, serologic surveillance of hunter-killed elk was conducted in northeastern and southeastern idaho. prevalence of antibodies in these elk varied annually, but averaged between 2% and 3%. elk were also trapped in northeastern idaho from 1998-2002 and ...	2006	16870849
behavioral responses of bison and elk in yellowstone to snowmobiles and snow coaches.	managers of public lands are charged with protecting some of our most important natural resources and ecosystems, while providing for their use and enjoyment by visitors. almost one million visitors entered yellowstone national park by motorized means on snowmobiles (87%) or snow coaches (13%) during 1992-2003. most vehicles toured the central portion of the park where bison (bison bison) and elk (cervus elaphus) concentrate in geothermal areas. we sampled >6500 interactions between groups of th ...	2006	17069382
levels of abnormal prion protein in deer and elk with chronic wasting disease.	chronic wasting disease (cwd) of deer and elk is a widespread health concern because its potential for crossspecies transmission is undetermined. cwd prevalence in wild elk is much lower than its prevalence in wild deer, and whether cwd-infected deer and elk differ in ability to infect other species is unknown. because lymphoid tissues are important in the pathogenesis of some transmissible spongiform encephalopathies such as sheep scrapie, we investigated whether cwd-affected elk and deer diffe ...	2007	17553219
biodiversity consequences of alternative future land use scenarios in greater yellowstone.	land use is rapidly expanding in the greater yellowstone ecosystem, primarily from growth in the number of rural homes. there is a need to project possible future land use and assess impacts on nature reserves as a guide to future management. we assessed the potential biodiversity impacts of alternative future land use scenarios in the greater yellowstone ecosystem. an existing regression-based simulation model was used to project three alternative scenarios of future rural home development. the ...	2007	17555214
density dependence and climate effects in rocky mountain elk: an application of regression with instrumental variables for population time series with sampling error.	1. sampling error in annual estimates of population size creates two widely recognized problems for the analysis of population growth. first, if sampling error is mistakenly treated as process error, one obtains inflated estimates of the variation in true population trajectories (staples, taper & dennis 2004). second, treating sampling error as process error is thought to overestimate the importance of density dependence in population growth (viljugrein et al. 2005; dennis et al. 2006). 2. in ec ...	2009	19549144
wolf presence and increased willow consumption by yellowstone elk: implications for trophic cascades.	recent increases in the height and growth ring width of willow (salix spp.) and other woody plants in the greater yellowstone ecosystem (gye) have been attributed to a behaviorally mediated trophic cascade from wolves (canis lupus) to elk (cervus elaphus) to willows. this hypothesis predicts that individual elk consume less willow in response to the presence of wolves, but this prediction has not been directly tested with data from elk. we collected 727 fecal samples from elk in the gallatin can ...	2009	19769124
echinococcus granulosus in gray wolves and ungulates in idaho and montana, usa.	we evaluated the small intestines of 123 gray wolves (canis lupus) that were collected from idaho, usa (n=63), and montana, usa (n=60), between 2006 and 2008 for the tapeworm echinococcus granulosus. the tapeworm was detected in 39 of 63 wolves (62%) in idaho, usa, and 38 of 60 wolves (63%) in montana, usa. the detection of thousands of tapeworms per wolf was a common finding. in idaho, usa, hydatid cysts, the intermediate form of e. granulosus, were detected in elk (cervus elaphus), mule deer ( ...	2009	19901399
probable causes of increasing brucellosis in free-ranging elk of the greater yellowstone ecosystem.	while many wildlife species are threatened, some populations have recovered from previous overexploitation, and data linking these population increases with disease dynamics are limited. we present data suggesting that free-ranging elk (cervus elaphus) are a maintenance host for brucella abortus in new areas of the greater yellowstone ecosystem (gye). brucellosis seroprevalence in free-ranging elk increased from 0-7% in 1991-1992 to 8-20% in 2006-2007 in four of six herd units around the gye. th ...	2010	20349847
lead poisoning of bald (haliaeetus leucocephalus) and golden (aquila chrysaetos) eagles in the u.s. inland pacific northwest region--an 18-year retrospective study: 1991-2008.	to determine risk factors and seasonal trends of lead poisoning in bald (haliaeetus leucocephalus) and golden (aquila chrysaetos) eagles, blood lead levels were evaluated in eagles admitted from the inland pacific northwest region of the united states to the raptor rehabilitation program, college of veterinary medicine at washington state university from 1991 to 2008. admissions were from washington (32 bald eagles, 27 golden eagles), northern idaho (21 bald eagles, 25 golden eagles), northeaste ...	2010	21302758
climate change intensification of herbivore impacts on tree recruitment.	altered species interactions are difficult to predict and yet may drive the response of ecological communities to climate change. we show that declining snowpack strengthens the impacts of a generalist herbivore, elk (cervus elaphus), on a common tree species. thick snowpack substantially reduces elk visitation to sites; aspen (populus tremuloides) shoots in these areas experience lower browsing rates, higher survival and enhanced recruitment. aspen inside herbivore exclosures have greatly incre ...	2011	21976686
an ecological perspective on brucella abortus in the western united states.	after a hiatus during the 1990s, outbreaks of brucella abortus in cattle are occurring more frequently in some of the western states of the united states, namely, montana, wyoming and idaho. this increase is coincidentwith increasing brucellosis seroprevalence in elk (cervus elaphus), which is correlated with elk density. vaccines are a seductive solution, but their use in wildlife systems remains limited by logistical, financial, and scientific constraints. cattle vaccination is ongoing in the ...	2013	23837367
ecosystem scale declines in elk recruitment and population growth with wolf colonization: a before-after-control-impact approach.	the reintroduction of wolves (canis lupus) to yellowstone provided the unusual opportunity for a quasi-experimental test of the effects of wolf predation on their primary prey (elk--cervus elaphus) in a system where top-down, bottom-up, and abiotic forces on prey population dynamics were closely and consistently monitored before and after reintroduction. here, we examined data from 33 years for 12 elk population segments spread across southwestern montana and northwestern wyoming in a large scal ...	2014	25028933
dances with anthrax: wolves (canis lupus) kill anthrax bacteremic plains bison (bison bison bison) in southwestern montana.	bacillus anthracis, the cause of anthrax, was recovered from two plains bison (bison bison bison) cows killed by wolves (canis lupus) in montana, usa, without associated wolf mortality in july 2010. this bison herd experienced an epizootic in summer 2008, killing ∼ 8% of the herd, the first documented in the region in several decades. no wolf deaths were associated with the 2008 event. surveillance has continued since 2008, with research, ranch, and wildlife personnel diligent during summer. as ...	2014	24484485
brucellosis transmission between wildlife and livestock in the greater yellowstone ecosystem: inferences from dna genotyping.	the wildlife of the greater yellowstone ecosystem carries brucellosis, which was first introduced to the area by cattle in the 19th century. brucellosis transmission between wildlife and livestock has been difficult to study due to challenges in culturing the causative agent, brucella abortus . we examined b. abortus transmission between american bison ( bison bison ), rocky mountain elk ( cervus elaphus nelsoni), and cattle ( bos taurus ) using variable number tandem repeat (vntr) markers on dn ...	2017	28118557