Piecewise-linear pseudodiagrams

There are 2^n possible resolutions of a smooth pseudodiagram with n precrossings. If we consider piecewise-linear (PL) pseudodiagrams and resolutions that themselves are PL, certain resolutions of the pseudodiagram may not exist in three-space. We investigate this situation and its impact on the weighted resolution set of PL pseudodiagrams as well as introduce a concept specific to PL pseudodiagrams, the forcing number. Our main result classifies the PL shadows whose weighted resolution sets differ from the weighted resolution set that would exist in the smooth case.Comment: 7 pages, 8 figures; V2 fixes a minor typo in both statement of Cor. 2.8 and in its proo

Wolf Disease Summary 2004-2014

Canine distemper virus (CDV), canine parvovirus (CPV), canine adenovirus (CAV), canine herpesvirus (CHV), neosporosis, leptospirosis, Brucella abortus and B. canis are diseases that have wolf health or wildlife management implications. Blood serum samples from wolves captured and collared for management purposes between 2004-2014 were screened for these pathogens. Serologic tests for leptospirosis, B. abortus, and B. canis were completed by the Montana Department of Livestock Diagnostic Laboratory with the remaining tests performed by Cornell University Animal Health Diagnostic Center (Cornell University, AHDC).  Samples were assigned as being collected in the Northwest or Southwest region of the state based on capture location and the region designation provided by Montana Fish, Wildlife and Parks wolf specialists. We evaluated and compared pathogen presence and prevalence within Northwest and Southwest Montana.  Each disease and its potential implications in the Northwest and Southwest region is discussed

Brucellosis in the Greater Yellowstone Area: A Multi-State Issue with Varying Management Paradigms Influencing Management and Possible Eradication of the Disease in Wildlife

Brucellosis, caused by the bacteria Brucella abortus, is an infectious disease of cattle, bison (Bison bison) and elk (Cervus elephus). The Greater Yellowstone Area (GYA) is the last known reservoir of the disease in the lower 48 states. Recent cases of the disease in cattle herds of Idaho, Montana and Wyoming have been attributed to exposure from wild elk and have brought increased focus on management and eradication of the disease from wildlife populations. Elk management programs within the three states of Idaho, Montana and Wyoming differ in response to the disease. Efforts to manage the disease within the GYA are greatly influence by management actions taken within individual states. The differing management actions and the potential influence on brucellosis management and possible eradication are discussed

Hemorrhagic Disease in Montana

Hemorrhagic Disease (HD) is caused by two groups of orbiviruses, bluetongue (BT) and epizootic hemorrhagic disease (EHD).   Both BT and EHD are capable of causing large scale mortalities in white-tailed deer.   Although both are capable of causing disease in other species, BT typically causes clinical symptoms and mortality in a larger range of species, including pronghorn and domestic sheep.   Three subtypes of EHD and five subtypes of BT are known to exist in North America.  Only EHD subtype 2 and BT subtype 17 have been identified in Montana.  Both BT and EHD are transmitted by a biting midge and the onset of disease typically occurring in late summer/early fall with mortality cases decreasing rapidly after the first killing frost.  HD was first documented in Montana in 1961.  Montana Fish, Wildlife and Parks has participated in a national survey documenting HD occurrence since that time.  Outbreaks within Montana appear to be becoming more frequent and the area affected has increased.  Until 2013 HD had been limited to the east side of the Rocky Mountain front.  However, in 2013 several counties in western Montana experience their first recorded EHD die-off in white-tailed deer.  The history and potential future ramifications of HD outbreaks in MT are discussed

Pneumonia Outbreak in Bighorn Sheep in the East Fork of the Bitterroot: A Summary of Pathology and Laboratory Findings

A bighorn sheep (Ovis Canadensis) pneumonia outbreak began in the East Fork of the Bitterroot River drainage in late November 2009. The decision to cull apparently sick animals provided the unique opportunity to collect fresh, high quality biological samples for diagnostic testing. It is our hope that information gained from this outbreak will contribute to an understanding of bighorn sheep pneumonia outbreaks in western states. The Montana Fish, Wildlife, and Parks wildlife laboratory performed full necropsies on many of the bighorn sheep that died or were culled during this outbreak. Body condition score and severity of lung lesions was noted. A fresh blood sample and fecal sample was collected, and the pharynx and ear canal were swabbed. Lung, tracheobronchial lymph node, and liver samples were also collected. Field personnel collected fresh tissue samples from culled sheep that could not be removed from the field for necropsy. Tissues and swabs were submitted to Washington Animal Disease Diagnostic Laboratory (WADDL) for aerobic and Mycoplasma culture. Serum and fecal samples were submitted to the Montana Department of Livestock laboratory in Bozeman. In this presentation we will describe the gross pathology of the pneumonia outbreak, summarize all laboratory findings, and describe similarities and differences when compared to other bighorn sheep pneumonia outbreaks within Montana and in other western states

Culling as an Exploratory Field Technique to Reduce Overall Mortality During a Pasturella Spp. Outbreak in a Montana Bighorn Sheep Population

Several herds of Rocky Mountain bighorn sheep (Ovis Canadensis) in the United States and Canada have experienced all-age die-offs during outbreaks of Pasturella spp. Induced pneumonia. Isolating triggers and remedies for these die-offs remains elusive. Montana Fish, Wildlife and Parks used the statewide Draft Sheep Conservation Strategy as a guide in establishing a field culling-mobile laboratory-media response to a pneumonia/complex outbreak in the East Fork Bitterroot bighorn sheep herd. Montana Fish, Wildlife and Parks employees along with volunteers from the Ravalli County Fish and Wildlife Association, Wild Sheep Foundation and the USDA Forest Service culled 76 sheep from a herd numbering at least 187 animals according to spring 2009 aerial observations. Field personnel discovered six recent bighorn sheep carcasses when culling efforts began in late November. Field personnel discovered one additional bighorn carcass during the three-month culling process. Lab experts conducting onsite necropsies observed evidence of infection in 73 (96%) of the culled sheep. State biologists observed 93 bighorns on this winter range during a cursory aerial survey conducted on 28 December 2009. Preliminary observations from comparing results of sheep selected for culling to field necropsies suggest field personnel detect infected sheep with a high degree of accuracy. We suggest that this technique prevented additional mortalities directly related to pneumonia

Assessing Brucellosis Seroprevalence and Transmission Risk in a Free-Ranging Elk Population: The Targetted Brucellosis Surveillance Project in Montana

Brucellosis is a bacterial disease that affects elk, bison and domestic cattle.  Recently the seroprevalence of brucellosis in free-ranging elk populations of Montana has increased and its’ range has expanded, resulting in increased pressure on Montana Fish, Wildlife and Parks (MFWP) to manage the disease in elk.  In 2010 MFWP and the Montana Department of Livestock initiated a targeted surveillance program to delineate the current geographic distribution of brucellosis, document spatio-temporal habitat selection and movement patterns, and to quantify potential transmission risk from elk to cattle.  Since 2010, we have targeted 11 different winter ranges from 9 hunt districts, both within and outside of the Designated Surveillance Area used to manage cattle.  During each capture operation we tested approximately 100 adult female elk for exposure to brucellosis.  We deployed GPS radiocollars on a subsample of adult female elk on each winter range.  An epidemiological summary of the first five years, including seroprevalence, movement and implications for transmission vectors will be presented. Current brucellosis exposure in domestic herds, future surveillance areas, evaluation of various management actions on transmission risk, and the creation of a spatio-temporal risk model are discussed

Predicting the Impact of Climate Change on Cheat Grass (Bromus tectorum) Invasibility for Northern Utah: A GIS and Remote Sensing Approach

Cheat grass (Bromus tectorum) invasibility represents a serious threat to natural ecosystems dominated by sagebrush (Artemisia tridentata). Ecosystem susceptibility to annual grass invasion seems to be driven by specific biophysical conditions. The study was conducted in Rich County, Utah, where cheat grass invasion is not yet an apparent problem, but an imminent invasion might be just a matter of time (temporal scale) to meet spatial variations in environmental conditions (spatial scale). Literature review and expert knowledge were used to define biophysical variables and their respective suitability ranges of where cheat grass takeover might occur. GIS, remote sensing and logistic regression-statistical analyses were employed to estimate probability of cheat grass invasion along environmental gradients. GIS procedures were used to spatially predict areas prone to be invaded by cheat grass under present climatic conditions (model prediction power was 47 percent). Afterwards, simulated climatic change projections (for 2099 year) from the Community Climatic System Model (CCSM-3) were used to model the invasibility risk of cheat grass. The 2099 cheat grass prediction map showed a favorable reduction of around 25 percent in the areas affected by cheat grass invasion, assuming that climate changes occurred as predicted by the CCSM model. The location of highly predisposed areas can be useful to alert managers and define where resources might be allocated to reduce a potential invasion and preserve native rangeland ecosystems

Identifying Priority Areas for Chronic Wasting Disease Surveillance in Montana

Chronic Wasting Disease is a fatal prion disease affecting ungulate species throughout North America.  As of 2013, no CWD positive deer have been found in the state of Montana, however, several surrounding states and provinces have identified multiple cases of the disease.  We used information on mule deer habitat selection, abundance, and locations of CWD cases in surrounding states to identify priority areas in Montana for CWD surveillance. The habitat selection models were based on over 10000 VHF and GPS locations collected from mule deer from 1975-2011, and predicted resource selection function (RSF) values for winter and summer in 5 of the 7 wildlife management regions in the state of Montana. We estimated mule deer density using the aerial survey counts weighted by the value of the RSF for each pixel. High priority areas were those that contained the highest densities of mule deer and were closest to locations with CWD positive deer. This information can be used to inform Montana’s CWD surveillance program for mule deer. We concluded that based on mule deer distribution and movement patterns several mule deer herds in Montana were at risk of coming into contact with deer from known infected herds

Elk Movements and Brucellosis Transmission Risk in Southwest Montana

The presence of Brucella abortus within free-ranging elk populations is an important conservation and management issue because of the risk of brucellosis transmission to livestock. Understanding elk distributions is necessary to forecast elk and livestock spatial overlap and the potential for brucellosis transmission. As part of a 5-yr brucellosis surveillance project, 30 adult female elk were captured and fitted with GPS collars in each of the winters of 2010, 2011 and 2012 in three southwest Montana study areas. We used elk location information to assess elk movements, and spatial overlap with livestock and adjacent elk herds. The elk movement results were further augmented with data from Wyoming and Idaho elk herds. The elk movement data shows interchange of females between elk herds during the transmission risk period. Resource selection models predicting elk distribution and spatial overlap with livestock during the transmission risk period were developed and extrapolated across the designated brucellosis surveillance area of Montana. We used the elk location data collected in this study to validate and refine models predicting elk distributions and spatial overlap with livestock during the risk period. Predictive models may be used as a tool for focusing management actions aimed at minimizing elk and livestock spatial overlap during the transmission risk period