723 research outputs found

    Home Range and Space Use of Northern Bobwhite Under Two Different Management Models in Southwestern Missouri

    Get PDF
    Northern bobwhite (Colinus virginianus; hereafter, bobwhite) management in Missouri, USA has traditionally been focused on providing an interspersion of grass, crop, old field, and woody cover juxtaposed to disked idle areas and food plots to maintain bobwhite populations. This traditional model is implemented with the goal of providing all essential habitat components within 40-acre blocks throughout a larger area used by a population. While this model can produce usable bobwhite space in agriculture-dominated landscapes, it may not be the most effective or efficient approach to producing and maintaining bobwhite in grassland-dominated landscapes. In southwestern Missouri native tallgrass prairie conservation areas are managed primarily with historical ecological processes, such as fire and grazing, to produce the desired patchy habitat mosaic. Additionally, it has been on these native tallgrass prairie conservation areas that managers have seen the most stable and productive bobwhite populations. Over a 5-year period (2014–2018) we quantified movements of northern bobwhite on 3 traditionally managed areas (n = 185) and on 3 managed native tallgrass prairie conservation areas (n = 211) to determine whether home range sizes and space use differed between these two management models. We used the 6-month (Apr–Sep) breeding period to determine core area, home range, mean movement rate, and maximum distance moved. Overall (pooled) home ranges of bobwhite did not differ significantly between traditional and grassland managed areas; however, there were significant yearly differences between management models and study areas. Males generally had larger home range sizes and had higher movement rates than females. For the 5 years of the study few birds made long-distance movements (\u3e1.6 km; 3%), and all remained relatively close to capture locations in winter (Feb–Mar). For both traditional and grassland managed areas, bobwhite selected for areas that had disturbance (fire and grazing) in the last 2 years and for the native grassland vegetation type. These findings suggest that areas managed under the grassland management model provide preferred habitat for bobwhite and could result in significant improvement in habitat quality for tallgrass prairie wildlife

    Breeding Season Survival and Nesting of Northern Bobwhite on Native Prairie Versus Traditionally Managed Conservation Areas in Southwestern Missouri

    Get PDF
    Northern bobwhite (Colinus virginianus) management on Missouri Conservation Area lands has traditionally focused on providing an interspersion of grass, crop, old field and woody cover to enhance edge habitat often juxtaposed with disked idle areas and food plots. This traditional approach, or the Intensive Management Model (IMM), is often implemented with the goal of providing all essential habitat components within a 40-acre area. While this model can produce useable quail habitat in agriculture-dominated landscapes it may not be the most effective or efficient approach to producing quail in grassland-dominated landscapes found in southwest Missouri. Conservation area mangers for the Missouri Department of Conservation (MDC) have historically implemented IMM in these grass-dominated landscapes; however in a few areas managers have begun using historical ecological processes, such as fire with grazing, or the Extensive Management Model (EMM) in conjunction with IMM or as the primary means for producing the patchy habitat mosaic preferred by bobwhite quail. In 2015, MDC began a 5 year study radio marking 60 individuals per area on 4 areas (2 IMM and 2 EMM) to compare the utility of these two models and the habitat conditions they create on breeding season vital rates (survival and production). Over the first 2 years of this study, EMM areas had higher breeding season survival (0.414 compared to 0.275) and nesting success (0.437 compared to 0.355) relative to IMM areas. Additionally, covey break-up and nest initiation were in general earlier, and clutch sizes were larger on areas managed with EMM than on areas managed with IMM

    Probing of RNA structures in a positive sense RNA virus reveals selection pressures for structural elements.

    Get PDF
    In single stranded (+)-sense RNA viruses, RNA structural elements (SEs) play essential roles in the infection process from replication to encapsidation. Using selective 2'-hydroxyl acylation analyzed by primer extension sequencing (SHAPE-Seq) and covariation analysis, we explore the structural features of the third genome segment of cucumber mosaic virus (CMV), RNA3 (2216 nt), both in vitro and in plant cell lysates. Comparing SHAPE-Seq and covariation analysis results revealed multiple SEs in the coat protein open reading frame and 3' untranslated region. Four of these SEs were mutated and serially passaged in Nicotiana tabacum plants to identify biologically selected changes to the original mutated sequences. After passaging, loop mutants showed partial reversion to their wild-type sequence and SEs that were structurally disrupted by mutations were restored to wild-type-like structures via synonymous mutations in planta. These results support the existence and selection of virus open reading frame SEs in the host organism and provide a framework for further studies on the role of RNA structure in viral infection. Additionally, this work demonstrates the applicability of high-throughput chemical probing in plant cell lysates and presents a new method for calculating SHAPE reactivities from overlapping reverse transcriptase priming sites

    LAURA Users Manual: 5.6

    Get PDF
    This users manual provides in-depth information concerning installation and execution of Laura, version 5. Laura is a structured, multiblock, computational aerothermodynamic simulation code. Version 5 represents a major refactoring of the original Fortran 77 Laura code toward a modular structure afforded by Fortran 95. The refactoring improved usability and maintainability by eliminating the requirement for problem-dependent recompilations, providing more intuitive distribution of functionality, and simplifying inter- faces required for multi-physics coupling. As a result, Laura now shares gas-physics modules, MPI modules, and other low-level modules with the Fun3D unstructured-grid code. In addition to internal refactoring, several new features and capabilities have been added, e.g., a GNU-standard installation process, parallel load balancing, automatic trajectory point sequencing, free-energy minimization, and coupled ablation and flow field radiation

    Contrasting approaches to 'doing' family meals: a qualitative study of how parents frame children's food preferences

    Get PDF
    Family meals, as acts of domestic food provisioning, are shaped by the competing influences of household resources, food preferences and broader cultural norms around dietary practices. The place of children's food tastes in family meal practices is particularly complex. Food tastes stand in a reciprocal relationship with family food practices: being both an influence on and a product of them. This paper explores how parents think about and respond to their children's food preferences in relation to family meal practices. A qualitative study was conducted with residents of Sandwell, UK. The results presented here are based on the responses of nine key participants and their families. Photo elicitation methods generated participant food photo diaries that were used to inform subsequent interviews. A thematic analysis revealed two contrasting ways of incorporating children's tastes into family meal routines: (1) 'what we fancy' and (2) 'regulated'. The former entails repeatedly consulting and negotiating with children over what to cook for each meal. It is supported by the practical strategies of multiple and individually modified meals. The latter relies upon parents developing a repertoire of meals that 'work' for the family. This repertoire is performed as a series of 'set meals' in which any requests for variation are strongly resisted. Our findings add to the small body of literature on household food provisioning and suggest that achieving the idealised ritual of the family meal is underpinned by a range of values and strategies, some of which may run counter to health messages about nutrition

    Northern Bobwhite Demographics and Resource Selection Are Explained by Prescribed Fire with Grazing and Woody Cover in Southwest Missouri

    Get PDF
    Understanding the effects of landscape management on northern bobwhite (Colinus virginianus; hereafter, bobwhite) population growth requires information about seasonal- and stage-specific demographic parameters linked across the annual cycle. We review results to date from 3 years (2016–2018) of an intensive field study evaluating drivers of bobwhite population dynamics and resource selection during the breeding and non-breeding season in southwest Missouri, USA using data from adult and juvenile bobwhite fitted with radio-transmitters. Land cover of our study sites ranged from large blocks of native grasslands maintained with prescribed fire and grazing to more traditional management resulting in small patches of grasslands interspersed with food plots, disked idle areas, and woody cover. During the breeding season, relative probability of selection by broods increased in relation to proportion of native grass managed by grazing and burning and proportion of cropland. Brood survival was also greatest on native grasslands burned and grazed within the past 2 growing seasons. During the fall and winter, relative probability of selection by adults increased as woody edge density increased. Fall and winter survival increased as distance from trees increased and decreased as distance to shrubs increased. Our integrated population model indicated that the number of young hatched per female and adult breeding season survival were greatest on sites with the most native grassland managed by prescribed fire with grazing. However, non-breeding season survival was greater on sites with more agriculture or food plots and woody cover. Abundance declined across all sites from 2016 to 2019. Our work suggests that native grasslands managed by prescribed fire with grazing can provide quail habitat superior to traditional management that strived for a mixture of agriculture, woody cover, and grassland. The combination of conservation grazing and fire in native grasslands interspersed with shrubs may provide the greatest chance for bobwhite populations to persist in southwest Missouri and similar landscapes

    Low-Cost X-Ray Inspection of Highly Attenuating Materials

    Get PDF
    As a result of an arms reduction treaty between the United States and the Russian Federation, both countries will each be storing over 40,000 containers of plutonium. To help detect any deterioration of the containers and prevent leakage, we are designing a digital radiography and computed tomography system capable of handling this volume reliably, efficiently, and at a lower cost.</p
    • …
    corecore