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2.
Ecol Appl ; 32(8): e2714, 2022 12.
Article En | MEDLINE | ID: mdl-36184581

A clear connection between basic research and applied management is often missing or difficult to discern. We present a case study of integration of basic research with applied management for estimating abundance of gray wolves (Canis lupus) in Montana, USA. Estimating wolf abundance is a key component of wolf management but is costly and time intensive as wolf populations continue to grow. We developed a multimodel approach using an occupancy model, mechanistic territory model, and empirical group size model to improve abundance estimates while reducing monitoring effort. Whereas field-based wolf counts generally rely on costly, difficult-to-collect monitoring data, especially for larger areas or population sizes, our approach efficiently uses readily available wolf observation data and introduces models focused on biological mechanisms underlying territorial and social behavior. In a three-part process, the occupancy model first estimates the extent of wolf distribution in Montana, based on environmental covariates and wolf observations. The spatially explicit mechanistic territory model predicts territory sizes using simple behavioral rules and data on prey resources, terrain ruggedness, and human density. Together, these models predict the number of packs. An empirical pack size model based on 14 years of data demonstrates that pack sizes are positively related to local densities of packs, and negatively related to terrain ruggedness, local mortalities, and intensity of harvest management. Total abundance estimates for given areas are derived by combining estimated numbers of packs and pack sizes. We estimated the Montana wolf population to be smallest in the first year of our study, with 91 packs and 654 wolves in 2007, followed by a population peak in 2011 with 1252 wolves. The population declined ~6% thereafter, coincident with implementation of legal harvest in Montana. Recent numbers have largely stabilized at an average of 191 packs and 1141 wolves from 2016 to 2020. This new approach accounts for biologically based, spatially explicit predictions of behavior to provide more accurate estimates of carnivore abundance at finer spatial scales. By integrating basic and applied research, our approach can therefore better inform decision-making and meet management needs.


Wolves , Animals , Humans , Ecosystem , Population Density , Social Behavior , Montana
3.
Proc Biol Sci ; 289(1966): 20212512, 2022 01 12.
Article En | MEDLINE | ID: mdl-35016539

Ecologists have long sought to understand space use and mechanisms underlying patterns observed in nature. We developed an optimality landscape and mechanistic territory model to understand mechanisms driving space use and compared model predictions to empirical reality. We demonstrate our approach using grey wolves (Canis lupus). In the model, simulated animals selected territories to economically acquire resources by selecting patches with greatest value, accounting for benefits, costs and trade-offs of defending and using space on the optimality landscape. Our approach successfully predicted and explained first- and second-order space use of wolves, including the population's distribution, territories of individual packs, and influences of prey density, competitor density, human-caused mortality risk and seasonality. It accomplished this using simple behavioural rules and limited data to inform the optimality landscape. Results contribute evidence that economical territory selection is a mechanistic bridge between space use and animal distribution on the landscape. This approach and resulting gains in knowledge enable predicting effects of a wide range of environmental conditions, contributing to both basic ecological understanding of natural systems and conservation. We expect this approach will demonstrate applicability across diverse habitats and species, and that its foundation can help continue to advance understanding of spatial behaviour.


Carnivora , Wolves , Animals , Ecosystem , Territoriality
4.
PLoS One ; 16(7): e0254827, 2021.
Article En | MEDLINE | ID: mdl-34293042

In the Northern Rockies of the United States, predators like wolves (Canis lupus) and mountain lions (Puma concolor) have been implicated in fluctuations or declines in populations of game species like elk (Cervus canadensis) and mule deer (Odocoileus hemionus). In particular, local distributions of these predators may affect ungulate behavior, use of space, and dynamics. Our goal was to develop generalizable predictions of habitat selection by wolves and mountain lions across western Montana. We hypothesized both predator species would select habitat that maximized their chances of encountering and killing ungulates and that minimized their chances of encountering humans. We assessed habitat selection by these predators during summer using within-home range (3rd order) resource selection functions (RSFs) in multiple study areas throughout western Montana, and tested how generalizable RSF predictions were by applying them to out-of-sample telemetry data from separate study areas. Selection for vegetation cover-types varied substantially among wolves in different study areas. Nonetheless, our predictions of 3rd order selection by wolves were highly generalizable across different study areas. Wolves consistently selected simple topography where ungulate prey may be more susceptible to their cursorial hunting mode. Topographic features may serve as better proxies of predation risk by wolves than vegetation cover-types. Predictions of mountain lion distribution were less generalizable. Use of rugged terrain by mountain lions varied across ecosystem-types, likely because mountain lions targeted the habitats of different prey species in each study area. Our findings suggest that features that facilitate the hunting mode of a predator (i.e. simple topography for cursorial predators and hiding cover for stalking predators) may be more generalizable predictors of their habitat selection than features associated with local prey densities.


Food Chain , Models, Biological , Predatory Behavior/physiology , Puma/physiology , Seasons , Wolves/physiology , Animals , Montana , Population Dynamics
5.
Ecol Appl ; 31(6): e02388, 2021 09.
Article En | MEDLINE | ID: mdl-34156123

Recently developed methods, including time-to-event and space-to-event models, estimate the abundance of unmarked populations from encounter rates with camera trap arrays, addressing a gap in noninvasive wildlife monitoring. However, estimating abundance from encounter rates relies on assumptions that can be difficult to meet in the field, including random movement, population closure, and an accurate estimate of movement speed. Understanding how these models respond to violation of these assumptions will assist in making them more applicable in real-world settings. We used simulated walk models to test the effects of violating the assumptions of the time-to-event model under four scenarios: (1) incorrectly estimating movement speed, (2) violating closure, (3) individuals moving within simplified territories (i.e., movement restricted to partially overlapping circles), (4) and individuals clustering in preferred habitat. The time-to-event model was robust to closure violations, territoriality, and clustering when cameras were placed randomly. However, the model failed to estimate abundance accurately when movement speed was incorrectly estimated or cameras were placed nonrandomly with respect to habitat. We show that the time-to-event model can provide unbiased estimates of abundance when some assumptions that are commonly violated in wildlife studies are not met. Having a robust method for estimating the abundance of unmarked populations with remote cameras will allow practitioners to monitor a more diverse array of populations noninvasively. With the time-to-event model, placing cameras randomly with respect to animal movement and accurately estimating movement speed allows unbiased estimation of abundance. The model is robust to violating the other assumptions we tested.


Animals, Wild , Ecosystem , Animals , Humans , Movement , Population Density
6.
Proc Biol Sci ; 288(1946): 20210108, 2021 03 10.
Article En | MEDLINE | ID: mdl-33653139

As an outcome of natural selection, animals are probably adapted to select territories economically by maximizing benefits and minimizing costs of territory ownership. Theory and empirical precedent indicate that a primary benefit of many territories is exclusive access to food resources, and primary costs of defending and using space are associated with competition, travel and mortality risk. A recently developed mechanistic model for economical territory selection provided numerous empirically testable predictions. We tested these predictions using location data from grey wolves (Canis lupus) in Montana, USA. As predicted, territories were smaller in areas with greater densities of prey, competitors and low-use roads, and for groups of greater size. Territory size increased before decreasing curvilinearly with greater terrain ruggedness and harvest mortalities. Our study provides evidence for the economical selection of territories as a causal mechanism underlying ecological patterns observed in a cooperative carnivore. Results demonstrate how a wide range of environmental and social conditions will influence economical behaviour and resulting space use. We expect similar responses would be observed in numerous territorial species. A mechanistic approach enables understanding how and why animals select particular territories. This knowledge can be used to enhance conservation efforts and more successfully predict effects of conservation actions.


Carnivora , Wolves , Animals , Montana , Selection, Genetic , Territoriality
7.
Acad Emerg Med ; 26(12): 1379-1383, 2019 12.
Article En | MEDLINE | ID: mdl-31328331

BACKGROUND: Pediatric seizures are commonly encountered in emergency medical services (EMS). Evidence is accumulating that the rate of hypoglycemia in this setting is low, challenging the concept of routine prehospital glucose measurement. OBJECTIVE: We studied factors associated with EMS protocol compliance for glucose testing in children < 18 years of age with a 9-1-1 call for seizure as well as rates of hypoglycemia in the prehospital setting. METHODS: We performed a retrospective analysis of data from the North Carolina EMS registry from 2013 to 2014. North Carolina EMS protocols require glucose measurement prior to seizure treatment. Scene calls for patients ≤ 17 years with a complaint of seizure were included. We calculated incidence of testing, hypoglycemia, and the relative risk of compliance with glucose measurement. RESULTS: There were 13,182 calls for seizure, of which 6,262 (47.5%, 95% confidence interval [CI] = 46.6% to 48.3%) had a glucose obtained. Hypoglycemia (glucose < 60 mg/dL) was present in 78 of 6,262 (1.25%, 95% CI = 0.97% to 1.5%) patients. Glucose was supplemented in 61 patients (median glucose 61 mg/dL, interquartile range = 51 to 67 mg/dL). Testing rates increased with age (relative risk [RR] = 1.04 per year, 95% CI = 1.03-1.04 per year), emergency medical technician-paramedic (EMT-P) presence (RR = 1.2, 95% CI = 1.1-1.3) and with antiepileptic medication use (RR = 1.24, 95% CI = 1.1 to 1.2). Testing was less likely in nonwhite patients (RR = 0.95, 95% CI = 0.92 to 0.98). CONCLUSIONS: Compliance is suboptimal, varying with patient age, race, and EMT-P presence. Testing increases when antiepileptic drugs are used. Hypoglycemia in tested patients was infrequent; however, proper treatment for hypoglycemic seizures will not be delivered if testing does not occur. It is worthwhile examining the utility of routine testing in this setting; however, until such time as protocols are revised, regional EMS administration should focus on education and uniform compliance with state protocols.


Blood Glucose/analysis , Guideline Adherence/statistics & numerical data , Hypoglycemia/diagnosis , Seizures/etiology , Adolescent , Anticonvulsants/therapeutic use , Child , Diagnostic Tests, Routine/statistics & numerical data , Emergency Medical Services/methods , Female , Humans , Hypoglycemia/blood , Hypoglycemia/complications , Hypoglycemic Agents/therapeutic use , Male , North Carolina , Retrospective Studies , Seizures/drug therapy
8.
J Anim Ecol ; 88(7): 1100-1110, 2019 07.
Article En | MEDLINE | ID: mdl-30951200

Ungulates migrate to maximize nutritional intake when forage varies seasonally. Populations of ungulates often include both migratory and non-migratory individuals, but the mechanisms driving individual differences in migratory behaviour are not well-understood. We quantified associations between hypothesized drivers of partial migration and the likelihood of migration for individual ungulates that experienced a range of environmental conditions and anthropogenic influences. We evaluated the effects of forage variation, conspecific density, and human land uses on migratory behaviour of 308 adult female elk in 16 herds across western Montana. We found irrigated agriculture on an individual's winter range reduced migratory behaviour, but individuals were more likely to migrate away from irrigated agricultural areas if better forage was available elsewhere or if they experienced high conspecific density on their winter range. When the forage available during the summer growing season varied predictably between years, elk were more likely to migrate regardless of whether they had access to irrigated agriculture. Our study shows that predictable availability of beneficial native forage can encourage migration even for ungulates with irrigated agriculture on their winter range. Perturbations that can affect the forage available to ungulates include wildfires, timber harvest, livestock grazing and changing weather patterns. If these or other disturbances negatively affect forage on summer ranges of migrants, or if they cause forage to vary unpredictably across space and time, our results suggest migratory behaviour may decline as a result.


Animal Migration , Deer , Agriculture , Animals , Ecosystem , Female , Humans , Montana , Seasons
9.
J Anim Ecol ; 86(5): 1094-1101, 2017 Sep.
Article En | MEDLINE | ID: mdl-28555834

Breeder turnover can influence population growth in social carnivores through changes to group size, composition and recruitment. Studies that possess detailed group composition data that can provide insights about the effects of breeder turnover on groups have generally been conducted on species that are not subject to recurrent annual human harvest. We wanted to know how breeder turnover affects group composition and how harvest, in turn, affects breeder turnover in cooperatively breeding grey wolves (Canis lupus Linnaeus 1758). We used noninvasive genetic sampling at wolf rendezvous sites to construct pedigrees and estimate recruitment in groups of wolves before and after harvest in Idaho, USA. Turnover of breeding females increased polygamy and potential recruits per group by providing breeding opportunities for subordinates although resultant group size was unaffected 1 year after the turnover. Breeder turnover had no effect on the number of nonbreeding helpers per group. After breeding male turnover, fewer female pups were recruited in the new males' litters. Harvest had no effect on the frequency of breeder turnover. We found that breeder turnover led to shifts in the reproductive hierarchies within groups and the resulting changes to group composition were quite variable and depended on the sex of the breeder lost. We hypothesize that nonbreeding females direct help away from non-kin female pups to preserve future breeding opportunities for themselves. Breeder turnover had marked effects on the breeding opportunities of subordinates and the number and sex ratios of subsequent litters of pups. Seemingly subtle changes to groups, such as the loss of one individual, can greatly affect group composition, genetic content, and short-term population growth when the individual lost is a breeder.


Reproduction , Wolves , Animals , Female , Idaho , Male , Population Growth , Sex Ratio
10.
Proc Biol Sci ; 284(1855)2017 May 31.
Article En | MEDLINE | ID: mdl-28539521

Recruitment in cooperative breeders can be negatively affected by changes in group size and composition. The majority of cooperative breeding studies have not evaluated human harvest; therefore, the effects of recurring annual harvest and group characteristics on survival of young are poorly understood. We evaluated how harvest and groups affect pup survival using genetic sampling and pedigrees for grey wolves in North America. We hypothesized that harvest reduces pup survival because of (i) reduced group size, (ii) increased breeder turnover and/or (iii) reduced number of female helpers. Alternatively, harvest may increase pup survival possibly due to increased per capita food availability or it could be compensatory with other forms of mortality. Harvest appeared to be additive because it reduced both pup survival and group size. In addition to harvest, turnover of breeding males and the presence of older, non-breeding males also reduced pup survival. Large groups and breeder stability increased pup survival when there was harvest, however. Inferences about the effect of harvest on recruitment require knowledge of harvest rate of young as well as the indirect effects associated with changes in group size and composition, as we show. The number of young harvested is a poor measure of the effect of harvest on recruitment in cooperative breeders.


Breeding , Cooperative Behavior , Wolves/physiology , Animals , Female , Male , Mortality , North America , Population Density , Reproduction
11.
AEM Educ Train ; 1(2): 140-150, 2017 Apr.
Article En | MEDLINE | ID: mdl-30051025

OBJECTIVES: Emergency medicine (EM) trainees are expected to learn to provide acute care for patients of all ages. The American Council for Graduate Medical Education provides some guidance on topics related to caring for pediatric patients; however, education about pediatric topics varies across residency programs. The goal of this project was to develop a consensus curriculum for teaching pediatric emergency care. METHODS: We recruited 13 physicians from six academic health centers to participate in a three-round electronic modified Delphi project. Participants were selected on the basis of expertise with both EM resident education and pediatric emergency care. The first modified Delphi survey asked participants to generate the core knowledge, skills, and experiences needed to prepare EM residents to effectively treat children in an acute care setting. The qualitative data from the first round was reformulated into a second-round questionnaire. During the second round, participants used rating scales to prioritize the curriculum content proposed during the first round. In round 3, participants were asked to make a determination about each curriculum topic using a three-point scale labeled required, optional, or not needed. RESULTS: The first modified Delphi round yielded 400 knowledge topics, 206 clinical skills, and 44 specific types of experience residents need to prepare for acute pediatric patient care. These were narrowed to 153 topics, 84 skills, and 28 experiences through elimination of redundancy and two rounds of prioritization. The final lists contain topics classified by highly recommended, partially recommended, and not recommended. The partially recommended category is intended to help programs tailor their curriculum to the unique needs of their learners as well as account for variability between 3- and 4-year programs and the amount of time programs allocate to pediatric education. CONCLUSION: The modified Delphi process yielded the broad outline of a consensus core pediatric emergency care curriculum.

12.
MedEdPORTAL ; 13: 10589, 2017 Jun 02.
Article En | MEDLINE | ID: mdl-30800791

INTRODUCTION: A patient that cannot be oxygenated or ventilated requires immediate and effective assessment, treatment, and transportation. Pediatric needle cricothyrotomy is used infrequently, therefore providers have a tendency to lose proficiency. Simulation training and evaluation are valuable tools to improve provider experience and skill. METHODS: A case was designed involving a 3-year-old male with a peanut allergy that presents with rash, swelling, and severe respiratory distress. The patient's respiratory distress and swelling worsens despite treatment with epinephrine and other allergic reaction medications. The patient then becomes unresponsive and impossible to oxygenate or ventilate. The primary objective of this case is airway management with needle cricothyrotomy in the pediatric population. A secondary objective is appropriate postprocedure management including appropriate ventilation rates and emergency medical transportation methods. RESULTS: This case was initially presented to 45 paramedics. Provider comfort with managing airway emergencies in young children improved from 47% to 89%. Confidence in performing pediatric needle cricothyrotomy improved from 16% to 87%. All providers felt the exercise was valuable and 98% felt the simulation provided appropriate realism. DISCUSSION: This scenario provides an outstanding opportunity for paramedic evaluation and training in pediatric needle cricothyrotomy and significantly improved the comfort level of providers' management of a failed pediatric airway. As we reflected on the use of this module, it was apparent that this was a very beneficial opportunity to spend one-on-one time between participants and their medical director. The training staff also benefited from the repeated emphasis of good assessment and treatment of a complex patient scenario.

13.
Health Care Manag (Frederick) ; 35(1): 39-46, 2016.
Article En | MEDLINE | ID: mdl-27892912

One of the most difficult undertakings for any employer is carrying out a decision to terminate an employee. Of all the employment-related actions taken by employers, the act of termination creates the greatest risk of legal liability. Many claims of employment discrimination filed with the Equal Employment Opportunity Commission arise from the act of termination. In many federal courts, employment-related lawsuits account for more than 50% of all court filings; these lawsuits cover a wide range of subjects, such as failure to hire, defamation, breach of contract, and harassment, to name a few. However, most employees sue because they have lost their job or fear they will lose their job. Because these individuals have virtually nothing to lose, they often see filing a claim with the Equal Employment Opportunity Commission or filing a lawsuit as the only viable option-often suing for wrongful discharge. With a thoughtful review of the issues and the legislation addressed in this article, health care managers can reduce the unnecessary risk of expensive, time-consuming litigation.


Employment/legislation & jurisprudence , Liability, Legal , Personnel Management/legislation & jurisprudence , Humans , United States
14.
Health Care Manag (Frederick) ; 35(2): 113-7, 2016.
Article En | MEDLINE | ID: mdl-27111682

The importance of proper documentation when taking any type of disciplinary action, particularly a termination, cannot be overstated. Proper documentation is a fundamental requirement placed upon employers by the courts when determining whether a termination is "legal." The following sample forms do not encompass all types of documentation that may be required for a given set of circumstances; they do provide the framework for health care managers to fashion their own forms to fit their employer's needs.


Documentation , Employment/legislation & jurisprudence , Personnel Management/legislation & jurisprudence , Humans
15.
Health Care Manag (Frederick) ; 33(2): 136-48, 2014.
Article En | MEDLINE | ID: mdl-24776832

As more and more individuals express themselves with tattoos and body piercings and push the envelope on what is deemed appropriate in the workplace, employers have an increased need for creation and enforcement of reasonable dress codes and appearance policies. As with any employment policy or practice, an appearance policy must be implemented and enforced without regard to an individual's race, color, sex, national origin, religion, disability, age, or any other protected status. A policy governing dress and appearance based on the business needs of an employer that is applied fairly and consistently and does not have a disproportionate effect on any protected class will generally be upheld if challenged in court. By examining some of the more common legal challenges to dress codes and how courts have resolved the disputes, health care managers can avoid many potential problems. This article, the third part of a 3-part examination of dress codes and appearance policies, focuses on the issues of race and national origin under the Civil Rights Act, disability under the Americans With Disabilities Act, and employees' rights to engage in concerted activities under the National Labor Relations Act. Pertinent court cases that provide guidance for employers are addressed.


Clothing/standards , Disabled Persons/legislation & jurisprudence , Organizational Policy , Workplace/legislation & jurisprudence , Body Piercing/legislation & jurisprudence , Body Piercing/standards , Civil Defense , Employment/legislation & jurisprudence , Employment/standards , Health Facilities/legislation & jurisprudence , Health Facilities/standards , Humans , Hygiene/legislation & jurisprudence , Hygiene/standards , Labor Unions/legislation & jurisprudence , Obesity , Occupational Health/legislation & jurisprudence , Occupational Health/standards , Tattooing/legislation & jurisprudence , Tattooing/standards , United States , Workplace/standards
16.
Proc Biol Sci ; 281(1782): 20140029, 2014 May 07.
Article En | MEDLINE | ID: mdl-24619446

As duration of snow cover decreases owing to climate change, species undergoing seasonal colour moults can become colour mismatched with their background. The immediate adaptive solution to this mismatch is phenotypic plasticity, either in phenology of seasonal colour moults or in behaviours that reduce mismatch or its consequences. We observed nearly 200 snowshoe hares across a wide range of snow conditions and two study sites in Montana, USA, and found minimal plasticity in response to mismatch between coat colour and background. We found that moult phenology varied between study sites, likely due to differences in photoperiod and climate, but was largely fixed within study sites with only minimal plasticity to snow conditions during the spring white-to-brown moult. We also found no evidence that hares modify their behaviour in response to colour mismatch. Hiding and fleeing behaviours and resting spot preference of hares were more affected by variables related to season, site and concealment by vegetation, than by colour mismatch. We conclude that plasticity in moult phenology and behaviours in snowshoe hares is insufficient for adaptation to camouflage mismatch, suggesting that any future adaptation to climate change will require natural selection on moult phenology or behaviour.


Adaptation, Physiological , Hares/physiology , Molting , Skin Pigmentation/physiology , Snow , Animals , Climate Change , Montana , Seasons
17.
Health Care Manag (Frederick) ; 33(1): 20-9, 2014.
Article En | MEDLINE | ID: mdl-24463587

As more and more individuals express themselves with tattoos and body piercings and push the envelope on what is deemed appropriate in the workplace, employers have an increased need for creation and enforcement of reasonable dress codes and appearance policies. As with any employment policy or practice, an appearance policy must be implemented and enforced without regard to an individual's race, color, gender, national origin, religion, disability, age, or other protected status. A policy governing dress and appearance based on the business needs of an employer that is applied fairly and consistently and does not have a disproportionate effect on any protected class will generally be upheld if challenged in court. By examining some of the more common legal challenges to dress codes and how courts have resolved the disputes, health care managers can avoid many potential problems. This article, the second part of a 3-part examination of dress codes and appearance policies, focuses on the issue of gender under the Civil Rights Act of 1964. Pertinent court cases that provide guidance for employers are addressed.


Civil Rights/legislation & jurisprudence , Clothing , Employment/legislation & jurisprudence , Body Modification, Non-Therapeutic , Female , Humans , Male , Prejudice/legislation & jurisprudence , United States
18.
Health Care Manag (Frederick) ; 32(4): 294-302, 2013.
Article En | MEDLINE | ID: mdl-24168864

As more and more individuals choose to express themselves and their religious beliefs with headwear, jewelry, dress, tattoos, and body piercings and push the envelope on what is deemed appropriate in the workplace, employers have an increased need for creation and enforcement of reasonable dress codes and appearance policies. As with any employment policy or practice, an appearance policy must be implemented and enforced without regard to an individual's race, color, sex, national origin, religion, disability, age, or any other protected status. A policy governing dress and appearance based on the business needs of an employer that is applied fairly and consistently and does not have a disproportionate effect on any protected class will generally be upheld if challenged in court. By examining some of the more common legal challenges to dress codes and how courts have resolved the disputes, health care managers can avoid many potential problems. This article addresses the issue of religious discrimination focusing on dress and appearance and some of the court cases that provide guidance for employers.


Body Modification, Non-Therapeutic , Civil Rights/legislation & jurisprudence , Clothing , Employment/legislation & jurisprudence , Prejudice/legislation & jurisprudence , Religion , Humans , United States
19.
PLoS One ; 8(6): e65808, 2013.
Article En | MEDLINE | ID: mdl-23840372

Large-scale presence-absence monitoring programs have great promise for many conservation applications. Their value can be limited by potential incorrect inferences owing to observational errors, especially when data are collected by the public. To combat this, previous analytical methods have focused on addressing non-detection from public survey data. Misclassification errors have received less attention but are also likely to be a common component of public surveys, as well as many other data types. We derive estimators for dynamic occupancy parameters (extinction and colonization), focusing on the case where certainty can be assumed for a subset of detections. We demonstrate how to simultaneously account for non-detection (false negatives) and misclassification (false positives) when estimating occurrence parameters for gray wolves in northern Montana from 2007-2010. Our primary data source for the analysis was observations by deer and elk hunters, reported as part of the state's annual hunter survey. This data was supplemented with data from known locations of radio-collared wolves. We found that occupancy was relatively stable during the years of the study and wolves were largely restricted to the highest quality habitats in the study area. Transitions in the occupancy status of sites were rare, as occupied sites almost always remained occupied and unoccupied sites remained unoccupied. Failing to account for false positives led to over estimation of both the area inhabited by wolves and the frequency of turnover. The ability to properly account for both false negatives and false positives is an important step to improve inferences for conservation from large-scale public surveys. The approach we propose will improve our understanding of the status of wolf populations and is relevant to many other data types where false positives are a component of observations.


Wolves/classification , Wolves/physiology , Animals , Conservation of Natural Resources , Databases, Factual , Ecosystem , Montana , Population Density , Population Dynamics , Surveys and Questionnaires
20.
Proc Natl Acad Sci U S A ; 109(31): 12752-7, 2012 Jul 31.
Article En | MEDLINE | ID: mdl-22807482

Bacteriophages deploy lysins that degrade the bacterial cell wall and facilitate virus egress from the host. When applied exogenously, these enzymes destroy susceptible microbes and, accordingly, have potential as therapeutic agents. The most potent lysin identified to date is PlyC, an enzyme assembled from two components (PlyCA and PlyCB) that is specific for streptococcal species. Here the structure of the PlyC holoenzyme reveals that a single PlyCA moiety is tethered to a ring-shaped assembly of eight PlyCB molecules. Structure-guided mutagenesis reveals that the bacterial cell wall binding is achieved through a cleft on PlyCB. Unexpectedly, our structural data reveal that PlyCA contains a glycoside hydrolase domain in addition to the previously recognized cysteine, histidine-dependent amidohydrolases/peptidases catalytic domain. The presence of eight cell wall-binding domains together with two catalytic domains may explain the extraordinary potency of the PlyC holoenyzme toward target bacteria.


Enzymes/chemistry , Streptococcus Phages/enzymology , Streptococcus equi/virology , Viral Proteins/chemistry , Crystallography, X-Ray , Protein Structure, Quaternary , Protein Structure, Tertiary
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