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The article focuses on Hamlin Garland, novelist and prominent man of letters, enthusiastically boarded a train in Chicago for Colorado Springs and the refreshing Rocky Mountains. It mentions Englishmen raised polo ponies and maintained a polo field and volunteered to accompany him on a camping trip into the remote mountains. It also mentions mountain sheep hunting and their alleged discovery of a lost mine and lived high in the mountains.

The purpose of this study was to evaluate the quality of mountain sheep milk obtained from animals kept on mountain pastures: natural and organic. The experimental procedure was conducted under production conditions, during annual grazing of mountain sheep on two mountain pastures in the region of the Polish Carpathians: on organic pasture certified for organic farming and natural mountain pasture belonging to the National Park. This study showed greater plant species diversity in the organic mountain pasture, but its yielding was lower than that of the natural pasture. The sward of the natural pasture was characterised by lower dry matter and fibre content but contained more total protein. The type of pasture did not affect the basic composition of the milk of mountain sheep, while differences were found in terms of acidity, alcohol number, fatty acid profile of fat and milk protein fractions. Milk obtained from sheep grazed on organic pasture was characterised by a higher proportion of medium chain fatty acids, as well as polyunsaturated fatty acids, and also essential unsaturated fatty acids, both linoleic acid, α-linolenic acid, γ-linolenic acid and arachidonic acid. In milk originating from the natural mountain pasture, a higher proportion of monounsaturated fatty acids, docosahexaenoic acid and the CLA c9-t11 isomer was found. The composition of milk protein fractions varied according to the location of grazing: milk from sheep grazing on natural pasture had a higher content of whey fractions, important for consumer health, milk from organic pasture had a higher content of κ-casein, of greatest importance in dairy processing technology. The floral composition of the pasture had an influence on the quality of sheep milk in relation to the fatty acid profile of fat and protein fractions of milk, which is important in terms of both the health-promoting and technological aspects of the raw material and may affect the quality of products made from it. [ABSTRACT FROM AUTHOR]

Mammals are imperiled worldwide, primarily from habitat loss or modification, and exhibit downward trends in their populations and distributions. Likewise, large-bodied herbivores have undergone a collapse in numbers and are at the highest extinction risk of all mammals. Bighorn sheep (Ovis canadensis) are among those large-bodied herbivores that possess a slow-paced life history, suffer from debilitating diseases, and have experienced range contractions across their historical distribution since the late 1800s. Translocations and reintroductions of these mountain ungulates are key aspects of restoration and often are used to re-establish populations in historical habitat or to supplement declining herds. Millions of US dollars and much effort by state and federal natural resource agencies, as well as public and private organizations, have been expended to restore bighorn sheep. Despite those efforts, translocated populations of bighorn sheep have not always been successful. We assessed restoration of bighorn sheep to provide insights in the context of conservation of populations of bighorn sheep, because this management tool is a frequently used to re-establish populations. We focused briefly on past efforts to restore bighorn sheep populations and followed with updates on the value of habitat enhancements, genetic issues, the importance of ecotypic or phenotypic adaptations when restoring populations, predation, and disease transmission. We also raised issues and posed questions that have potential to affect future decisions regarding the restoration of bighorn sheep. This information will help conservationists improve the success of conserving these iconic large mammals.

The aim of the research was to assess the quality of milk from mountain sheep used for the production of traditional cheeses, taking into account the influence of the breed, the month of milking, and the content of somatic cells. Milk for the study was obtained from sheep of three mountain breeds: Podhale Zackel (PZ), Polish Mountain Sheep (PMS), and Coloured Mountain Sheep (CMS). The sheep were grazed in mountain pastures after lamb weaning, in the period from May to October in the traditional system. No influence of the breed on the examined parameters was found, except for urea content. Mountain sheep milk was characterized by a content of 19.68% solids, 8.48% fat, 6.63% protein, in which almost 76% was formed by casein (4.99%), and the average lactose content was 4.15%. Other milk parameters also did not differ between breeds: density was 1034.04 g/L, acidity 11.34°SH, and mean somatic cell content was 982.13∙103∙ml−1 (log10SCC = 5.68). The highest urea content was recorded in the milk of Coloured Mountain Sheep (280.69 mg/L) and the lowest urea content was recorded in the milk of Zackel sheep (200.97 mg/L). The month of milking influenced the content of most milk components, but no changes in SCC content during lactation were found. Significant correlations between fat content and other milk parameters were recorded. In the case of urea content, negative, statistically significant correlations with the majority of examined parameters were found. [ABSTRACT FROM AUTHOR]

В наскальном искусстве западной части хребта Тарбагатай (Восточный Казахстан) выявлены спиралевидные фигуры, которые, по-видимому, изображали лабиринты – такие фигуры достаточно распространены в петроглифах Евразии и обычно связываются с представлениями о потустороннем мире. В рамках общепринятой концепции рассматриваются особенности этих изображений.

Abstract: Winters are limiting for many terrestrial animals due to energy deficits brought on by resource scarcity and the increased metabolic costs of thermoregulation and traveling through snow. A better understanding of how animals respond to snow conditions is needed to predict the impacts of climate change on wildlife. We compared the performance of remotely sensed and modeled snow products as predictors of winter movements at multiple spatial and temporal scales using a data set of 20,544 locations from 30 GPS‐collared Dall sheep (Ovis dalli dalli) in Lake Clark National Park and Preserve, Alaska, USA from 2005 to 2008. We used daily 500‐m MODIS normalized difference snow index (NDSI), and multi‐resolution snow depth and density outputs from a snowpack evolution model (SnowModel), as covariates in step selection functions. We predicted that modeled snow depth would perform best across all scales of selection due to more informative spatiotemporal variation and relevance to animal movement. Our results indicated that adding any of the evaluated snow metrics substantially improved model performance and helped characterize winter Dall sheep movements. As expected, SnowModel‐simulated snow depth outperformed NDSI at fine‐to‐moderate scales of selection (step scales < 112 h). At the finest scale, Dall sheep selected for snow depths below mean chest height (<54 cm) when in low‐density snows (100 kg/m3), which may have facilitated access to ground forage and reduced energy expenditure while traveling. However, sheep selected for higher snow densities (>300 kg/m3) at snow depths above chest height, which likely further reduced energy expenditure by limiting hoof penetration in deeper snows. At moderate‐to‐coarse scales (112–896 h step scales), however, NDSI was the best‐performing snow covariate. Thus, the use of publicly available, remotely sensed, snow cover products can substantially improve models of animal movement, particularly in cases where movement distances exceed the MODIS 500‐m grid threshold. However, remote sensing products may require substantial data thinning due to cloud cover, potentially limiting its power in cases where complex models are necessary. Snowpack evolution models such as SnowModel offer users increased flexibility at the expense of added complexity, but can provide critical insights into fine‐scale responses to rapidly changing snow properties. [ABSTRACT FROM AUTHOR]

Although mountain sheep systems suffer from climatic and environmental handicaps that constrain productivity and economic viability, they have an important economic role, maintain habitats and species of high nature conservation value and support the provision of a range of ecosystem services of benefit to society. Using Precision Livestock Farming (PLF) in extensive mountain sheep systems could bring benefits for animal performance, economical performance and labour. This paper presents results from a 3 year experiment where PLF principles were implemented on an extensive mountain sheep farm and an assessment made of whether or not such an approach could benefit more marginal sheep systems. A 900 ewe flock (600 Scottish Blackface ewes, 300 Lleyn ewes) was divided equally into two separate systems, one where the flock was managed conventionally (CON) at group level, and the other where the individuals in the flock were subjected to a PLF management protocol where electronic weighing, recording and drafting equipment were used, linked to the electronic identification (EID) tags of the animals. Two main management strategies were compared and contrasted; one relating to winter feeding of the pregnant ewes, the other relating to anthelmintic treatment of lambs during the summer. Yearly labour profiles were created by measuring the time spent doing individual tasks associated with the two management systems. Net margins (£/ewe) were calculated for the two systems. Additionally, the yearly labour profiles were scaled-up using commercial data to quantify potential labour savings on more traditionally managed mountain farms if PLF principles were adopted. Analyses indicated that the two different management systems did not result in any significant difference in terms of ewe weights, mid-pregnancy scanning figures, ewe and lamb mortality rates, or lamb weight post-weaning. However, the proportion of lambs needing anthelmintic treatment was significantly reduced by 40% between the CON and the PLF, resulting in a reduction of 46% in the amount of anthelmintic used. Over a whole year, the total amount of labour required in the PLF management system was reduced by 36%. Across the 3 years, the net margin for the two systems showed an average difference of £3/ewe higher in the PLF. For a more traditional farm embracing a PLF approach, analyses suggested labour reduction of 19%, equating to £1.60/ewe savings. This study shows that it is beneficial for farmers to consider managing a mountain ewe flock at an individual rather than at flock or batch level using PLF technology. [ABSTRACT FROM AUTHOR]

ABSTRACT Horns, antlers, and other horn-like structures are products of sexual selection, confer reproductive advantages, and are heritable and honest indicators of individual quality. In addition to serving key biological functions, horns and antlers garner societal interest that, when combined with the powerful motivation to acquire trophy animals, likely has spawned a growing hornographic culture fixated on males with exceptional horn-like structures. The concern that harvest of large, fast-growing males may cause evolutionary change to the very trait being sought has been the source of controversy in the popular and scientific literature over the past 2 decades. Mountain sheep (i.e., bighorn and thinhorn; Ovis spp.), possibly the only large ungulates in North America managed almost exclusively as trophy species throughout their ranges, embody this controversy, which has led to polarizing views among scientists and stakeholders as to how mountain sheep should be managed. Our goal in this commentary was to discuss the relative contributions of the key ecological and intrinsic factors that influence horn growth, how those factors might interact with harvest strategies, and identify what determinants of horn size are most amenable to management and most effective in achieving desired outcomes. Despite repeated results demonstrating that age or nutrition frequently override genetic contributions to size of horns, attention has been given to the role of genetics and its relationship to harvest of mountain sheep. Given the hyperbole surrounding trophy management and big horns, we suggest the importance of females in the management of mountain sheep has been largely forgotten. Maternal condition can instigate life-long effects on size and growth of males (via maternal effects), and abundance of females, in turn, affects nutritional limitation within populations through density-dependent feedbacks. If production of males with large horns is an objective, we contend that management programs should, integrate monitoring of nutritional status of populations, and where evidence indicates nutritional limitation through density dependence, seek to regulate abundance and per capita nutrition via harvest of females. We propose that extrinsic regulation (i.e., removal by harvest or translocation) is the most effective way to manage per capita availability of forage resources and, thus, nutritional limitation on growth of males. Not only can female harvest improve growth in body size and horns of males through enhanced nutrition of growing males and their mothers, such management also 1) may yield a nutritional buffer against environmental stochasticity and erratic population fluctuations, 2) be employed in areas where other management alternatives such as habitat manipulation may not be feasible, 3) may reduce frequency or magnitude of epizootic die-offs, and 4) will increase hunter opportunity and involvement in management. Ultimately, we call for greater recognition of the pervasive role of the ewe, and other female ungulates, in the production of trophy males, and that accordingly, females be better integrated into harvest and management programs. © 2017 The Wildlife Society. [ABSTRACT FROM AUTHOR]

It took years, at the dawn of the twentieth century, for the National Zoo to capture Rocky Mountain sheep. The split hooves and remarkable eyesight of bighorns made these animals virtually impossible to catch alive. This is a story about a national government chasing sheep for the purpose of zoological display. This is also a story about the construction of knowledge, the ironies of conservation, and the building of the American West. More important, this is a story about storytelling. The following tale will call attention to the opportunities that zoological parks, animal history, and narrative history offer the historian. [ABSTRACT FROM AUTHOR]

The article discusses abnormal coloration in Bighorn Sheep with scientific name Ovis canadensis. Topics discussed include abnormal white coloration manifested as albinism or leucism, presence of abnormally colored bighorn sheep in geographic areas from British Columbia southward to Baja California and study of D. M. Shackleton and H. McCardle on same.

ABSTRACT Good decision-making is essential to conserving wildlife populations. Although there may be multiple ways to address a problem, perfect solutions rarely exist. Managers are therefore tasked with identifying decisions that will best achieve desired outcomes. Structured decision making (SDM) is a method of decision analysis used to identify the most effective, efficient, and realistic decisions while accounting for values and priorities of the decision maker. The stepwise process includes identifying the management problem, defining objectives for solving the problem, developing alternative approaches to achieve the objectives, and formally evaluating which alternative is most likely to accomplish the objectives. The SDM process can be more effective than informal decision-making because it provides a transparent way to quantitatively evaluate decisions for addressing multiple management objectives while incorporating science, uncertainty, and risk tolerance. To illustrate the application of this process to a management need, we present an SDM-based decision tool developed to identify optimal decisions for proactively managing risk of pneumonia epizootics in bighorn sheep ( Ovis canadensis) in Montana. Pneumonia epizootics are a major challenge for managers due to long-term impacts to herds, epistemic uncertainty in timing and location of future epizootics, and consequent difficulty knowing how or when to manage risk. The decision tool facilitates analysis of alternative decisions for how to manage herds based on predictions from a risk model, herd-specific objectives, and predicted costs and benefits of each alternative. Decision analyses for 2 example herds revealed that meeting management objectives necessitates specific approaches unique to each herd. The analyses showed how and under what circumstances the alternatives are optimal compared to other approaches and current management. Managers can be confident that these decisions are effective, efficient, and realistic because they explicitly account for important considerations managers implicitly weigh when making decisions, including competing management objectives, uncertainty in potential outcomes, and risk tolerance. © 2016 The Wildlife Society. [ABSTRACT FROM AUTHOR]

European mouflons ( Ovis orientalis musimon) are Mediterranean sheep that were introduced worldwide as park and game animals during the last few centuries. Today, European mouflons are endangered in their natural refuge areas. Mouflons are able to interbreed with domestic breeds to form fertile hybrids of an intermediate phenotype. As some introduced mouflon populations were deliberately crossed with primitive domestic breeds to improve their hardiness and trophy size and as evidence of uncontrolled interbreeding exists, the alleged purity of most mouflon populations has been debated for decades. In this study, we developed a genetic test to separate pure bred mouflons and domestic sheep from their hybrids. We searched for hybridization using insertionally polymorphic endogenous retroviruses and a set of novel microsatellites. Three instances were found of domestic sheep alleles in a retrotype dataset out of 192 mouflons from Western Germany. Considering the combined outcome of microsatellite and retrotype profiling, the amount of hybridization is negligible. We assume that the selective hunting of animals that show signs of hybridization in their phenotype is responsible for the low number of hybrids. [ABSTRACT FROM AUTHOR]

The Laristan mouflon ( Ovis orientalis laristanica ) is considered as the smallest wild sheep in the world and a vulnerable species. This study analysed the mating behaviour of 30 individuals including nine rams, 13 ewes and eight lambs in captivity in the Chitgar woodland Tehran, Iran. In general, the main behaviours comprised ewe-ram and ram-ram positive and negative interactions, consisting of ram fighting and ewe's stimulation. Moreover, ewe-ewe interaction, ranking and defining the territory was recorded for further researches. The study also focused on weather conditions and its connection to the harshness of the mating behaviour. [ABSTRACT FROM AUTHOR]

We respond to Festa‐Bianchet (2019) and caution against using interpretations from the unique Ram Mountain history to justify management of mountain sheep throughout their range. Because harvest management at Ram Mountain is atypical, it is not useful in informing the management of most mountain sheep herds. [ABSTRACT FROM AUTHOR]

Bighorn sheep ( Ovis canadensis) were re- introduced into the Black Hills, South Dakota, U.S.A. in 1965. To date limited information exists concerning vital rates of this population. From 2010 to 2013, we estimated survival and cause-specific mortality of 55 adult female bighorn sheep in three herds in the east-central Black Hills. We documented 21 mortalities. Of those, pneumonia (19%) and predation (19%) accounted for most known causes of mortality; however, we were unable to ascertain cause of death for 47.6% of mortalities. We used a known fate analysis in Program MARK to estimate monthly survival; our best approximating model indicated survival differed during May-Jun compared with the remainder of the year. Monthly survival estimates for May-Jun were 0.95 (95% CI = 0.91-0.97) compared with 0.99 (95% CI = 0.98-0.99) for Jul-Apr, and overall annual survival was 0.81 (95% CI = 0.72-0.87). We found little support for the hypothesis that survival was influenced by body mass or nutritional condition (ingesta-free body fat). Our results indicated disease, predation, and other factors predisposing ewes to mortality, especially during and shortly after parturition, were contributors to the current demographic status of this population. [ABSTRACT FROM AUTHOR]

Large predators often suppress ungulate population growth, but they may also suppress the abundance of smaller predators that prey on neonatal ungulates. Antagonistic interactions among predators may therefore need to be integrated into predator-prey models to effectively manage ungulate-predator systems. We present a modeling framework that examines the net impact of interacting predators on the population growth rate of shared prey, using interactions among wolves Canis lupus, coyotes Canis latrans and Dall sheep Ovis dalli dalli as a case study. Wolf control is currently employed on approximately 16 million ha in Alaska to increase the abundance of ungulates for human harvest. We hypothesized that the positive effects of wolf control on Dall sheep population growth could be counteracted by increased levels of predation by coyotes. Coyotes and Dall sheep adult females (ewes) and lambs were radiocollared in the Alaska Range from 1999-2005 to estimate fecundity, age-specific survival rates, and causes of mortality in an area without wolf control. We used stage-structured population models to simulate the net effect of wolf control on Dall sheep population growth (λ). Our models accounted for stage-specific predation rates by wolves and coyotes, compensatory mortality, and the potential release of coyote populations due to wolf control. Wolves were the main predators of ewes, coyotes were the main predators of lambs, and wolves were the main source of mortality for coyotes. Population models predicted that wolf control could increase sheep λ by 4% per year in the absence of mesopredator release. However, if wolf control released coyote populations, our models predicted that sheep λ could decrease by up to 3% per year. These results highlight the importance of integrating antagonistic interactions among predators into predator-prey models, because the net effect of predator management on shared prey can depend critically on the strength of mesopredator release. [ABSTRACT FROM AUTHOR]

The current distribution of the bighorn sheep in Mexico represents a reduced proportion of its original area. Previous population genetics studies conducted in Mexico have only included data from Tiburon Island in the Gulf of California and few individuals from the continent. The aim of this article was to describe aspects of the population genetics of Mexican bighorn sheep in order to aid in the management and conservation of the species. We analyzed 117 samples from the states of Sonora and Baja California Sur using 91 intersimple sequence repeat loci. Our results indicated that the Mexican samples of bighorn sheep have relatively low levels of genetic diversity (H ≈ 0.26) and low genetic differentiation (ϴ ≈ 0.07) that may be the result of the recent colonization and origin of the populations in Mexico. The individuals from Southern Baja California are genetically different from the Sonoran sample, but this genetic differentiation is low, perhaps due to the low levels of genetic variation of the Mexican populations. The results obtained in this study are relevant for population management of the bighorn sheep in Mexico in order to design translocation plans and management strategies to maintain genetic diversity and, in consequence, the health and future survival of the populations. [ABSTRACT FROM AUTHOR]

ABSTRACT Use of global positioning system (GPS) transmitters provides opportunities to evaluate ecological questions associated with fine-scale animal movements. One important application is to evaluate how animals acclimate to new surroundings after translocation. Our objective was to quantify temporal acclimation for low-elevation, non-migratory bighorn sheep ( Ovis canadensis) from 3 translocations to the Seminoe Mountains in south-central Wyoming, USA, from 2009 to 2010 ( n = 38) as well as for bighorns captured and released on-site in 2011 ( n = 24). We used number of days for movements from individual bighorn to stabilize as a measure of acclimation. Mean acclimation for translocated bighorns after release was 29.3 days (SE = 2.5, range = 0-70). Mean acclimation for bighorns captured and released on-site was 5.0 days (SE = 2.4, range = 0-52). Paired comparisons indicated acclimation for 16 previously translocated bighorns that were captured and released on-site was reduced by 30.8 days (SE = 5.0) or 86%. Within translocation efforts, bighorn females in supplemental releases acclimated an average of 19.5 days sooner (or in 57% of the time) than animals from the first translocation. Because acclimation periods after translocation releases are associated with increased mortality risk, managers should consider supplemental releases to minimize acclimation periods. © 2014 The Wildlife Society. [ABSTRACT FROM AUTHOR]

Identifying patterns of fine-scale genetic structure in natural populations can advance understanding of critical ecological processes such as dispersal and gene flow across heterogeneous landscapes. Alpine ungulates generally exhibit high levels of genetic structure due to female philopatry and patchy configuration of mountain habitats. We assessed the spatial scale of genetic structure and the amount of gene flow in 301 Dall's sheep ( Ovis dalli dalli) at the landscape level using 15 nuclear microsatellites and 473 base pairs of the mitochondrial (mtDNA) control region. Dall's sheep exhibited significant genetic structure within contiguous mountain ranges, but mtDNA structure occurred at a broader geographic scale than nuclear DNA within the study area, and mtDNA structure for other North American mountain sheep populations. No evidence of male-mediated gene flow or greater philopatry of females was observed; there was little difference between markers with different modes of inheritance (pairwise nuclear DNA F = 0.004-0.325; mtDNA F = 0.009-0.544), and males were no more likely than females to be recent immigrants. Historical patterns based on mtDNA indicate separate northern and southern lineages and a pattern of expansion following regional glacial retreat. Boundaries of genetic clusters aligned geographically with prominent mountain ranges, icefields, and major river valleys based on Bayesian and hierarchical modeling of microsatellite and mtDNA data. Our results suggest that fine-scale genetic structure in Dall's sheep is influenced by limited dispersal, and structure may be weaker in populations occurring near ancestral levels of density and distribution in continuous habitats compared to other alpine ungulates that have experienced declines and marked habitat fragmentation. [ABSTRACT FROM AUTHOR]