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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Morphology and fluvial processes of the lower Red Deer River Valley, Alberta

McPherson, Harold J., 1936- January 1966 (has links)
No description available.
12

Morphology and fluvial processes of the lower Red Deer River Valley, Alberta

McPherson, Harold J., 1936- January 1966 (has links)
No description available.
13

Hybridisation and introgression of exotic Cervus (nippon and canadensis) with red deer (Cervus elaphus) in the British Isles

Smith, Stephanie Lindsay January 2013 (has links)
Europe’s largest population of wild red deer (Cervus elaphus) resides in the British Isles and has been present since the end of the last ice age, c. 11,000BP. Since the mid-19th century, multiple introductions of Japanese sika (Cervus nippon) and wapiti (Cervus canadensis) have taken place across the British Isles. While wapiti introductions have generally gone extinct, sika have thrived and expanded and now often live in sympatry with red deer. Hybridisation between these species has been demonstrated in captivity and in the wild. This study sought to determine the extent of hybridisation and introgression between red and sika across large parts of the British Isles and elucidate some of its potential consequences. Chapter 2 addresses the extent of hybridisation and introgression across Scotland and NW England. A total of 2984 samples from the North Highlands, the central Highlands, the Hebrides, Kintyre and the English Lake District were genotyped at 22 microsatellite loci, which are highly diagnostic for red and sika and strongly diagnostic for red and wapiti and a mitochondrial marker that is diagnostic for red and sika, alongside 49 wapiti samples from Canada. Microsatellite data was analysed using the Bayesian clustering program Structure 2.3 to determine the extent of admixture between species. There was some evidence for very low-level introgression by wapiti into a small number of Scottish red deer (<0.2% of total). Only two areas (both in Kintyre, Argyll) showed extensive introgression with collapse of assortative mating between red and sika (50.4% and 61.8% of sampled individuals were hybrid in West Loch Awe and South Kintyre, respectively). However, rare and widely scattered individuals with low-level sika introgression or cytonuclear disequilibrium suggest hybridisation has occurred in several other places in mainland Scotland and Cumbria in the past without subsequent loss of assortative mating. Chapter 3 addresses the extent of hybridisation in Ireland. There are now an estimated 4,000 red deer in Ireland and their numbers are increasing. It has recently been determined that the red deer in Killarney, County Kerry are descended from an ancient (c. 5,000BP) introduction and therefore merit genetic conservation. Introduction of exotic species, including Japanese sika and North America wapiti, since the 19th century have primarily occurred via the now defunct Powerscourt Park, County Wicklow, which was the source of many translocations to the rest of Ireland as well as to the UK. 374 deer samples from across Ireland were analysed as in Chapter 2. Wapiti introgression was again very low, with trace amounts of introgression detected in a small proportion of samples (0.53%), whilst 41% of 197 deer sampled in Co. Wicklow and 47% of 15 deer sampled in Co. Cork were red-sika hybrids according to either their nuclear genome or mitochondrial haplotype. No pure red deer were detected in Co. Wicklow, suggesting that in this region the red deer has disappeared following hybridisation. Whilst no hybrids were detected among 37 red samples and 77 sika samples in Co. Kerry, the Co. Cork hybrids pose a threat to the Killarney populations due to their proximity. Chapter 4 investigates population genetic structure within red and sika populations across the British Isles and investigates whether low-level introgression by the other species influences the resolved population structure. Structure analysis was conducted separately using 2307 ‘pure’ red deer individuals and 752 ‘pure’ sika animals from the British Isles (defined as Q > 0.95 for red and Q < 0.05 for sika) and then on reduced sample sizes using more stringent purity criteria (Q ≥ 0.99 and Q ≤ 0.01). As might be predicted, the more stringent criteria removed individuals in areas known to contain advanced backcrosses. In red deer, there was some evidence for a loss of within-species population structure under the more stringent criteria, while for sika there was not. Datasets were also analysed using Discriminate Analysis of Principal Components; a multivariate method designed to infer and describe genetic population structure. In red deer, both analytical approaches confirmed the strong separation of the deer on Harris and Lewis from others, and there is support for clusters typified by the other Hebridean islands, Kintyre, central and North Scotland and the English sites. Among sika, both approaches supported the likelihood of three clusters which are presumably the result of bottleneck events as each introduction was made. Chapter 5 investigates the phenotypic consequences of hybridisation by three approaches. Firstly, carcass weight was regressed against genetically-determined hybrid scores (at two stringency levels, see Chapter 4) and heterozygosity (in terms of red and sika alleles). Among hybrids, carcass weight is linearly related to hybrid score (Q) and there is some evidence for a positive relationship with heterozygosity. This suggests that additive genetic variation explains variation in carcass weight to a greater extent than heterosis. Secondly, analysis of five case studies representing individual putative hybrids submitted by stalkers from areas without known hybridisation, two proved to be hybrids, while the other three were pure sika. Lastly, in regions known to contain hybrids, the accuracy of ranger-assigned phenotype averaged 78% and revealed that in Scotland accuracy tends to decline as an individual becomes more genetically intermediate; whilst in Co. Wicklow it is the identification of pure parental animals that is more challenging. In conclusion, the existence of rare and widely scattered advanced red-sika backcrosses with low-level nuclear introgression and/or mitochondrial introgression (e.g. in North of Scotland, Cumbria) highlight that some hybridisation events are followed by extensive backcrossing without the breakdown of assortative mating, while others are followed by the generation of a hybrid swarm (e.g. in South Kintyre, West Loch Awe, Co. Wicklow, Co. Cork). Phenotypic traits can become intermediate due to hybridisation and this may facilitate further gene flow and hybridisation. New molecular tools including next generation sequencing (NGS) will enable better understanding the hybridisation process and its phenotypic consequences in this and other systems.
14

Causes and consequences of sexual selection in a wild population

Stopher, Katie Vivienne January 2011 (has links)
Although sexual selection in nature has been studied intensively, much is still unknown about the evolution of mating systems in wild populations: for example, how male competition and female choice interact, or the effect of environmental heterogeneity on selection. Further, important questions remain about the consequences of sexual selection for genetic structuring and genetic variation within populations. In this thesis, I investigate the causes and consequences of sexual selection in a polygynous mammal, the red deer Cervus elaphus. This species is characterized by high male reproductive skew resulting from competition to defend harems of females. Here however, I present evidence for previously unappreciated complexity in the mating system, in terms of female mating behaviour and environmental influences on male-male competition. I then go on to investigate the consequences of non-random mating on co-ancestry and inbreeding in the population. Finally, I investigate methods for separating genetic and environmental sources of covariance between individuals. Specifically, I: (i) Show a surprising degree of female mobility during the breeding season (the 'rut‘). Around 40% of females change harem when in oestrus and almost half of these movements result in paternity for the novel male; however I show that these movements are unlikely to be explained by female choice for mates. (ii) Reveal that variance in male mating success is affected by variation in ecological parameters, in particular the interaction between the number of immigrant males in the rutting population and the temporal synchrony of females. (iii) Demonstrate substantial inter-individual differences in the plasticity of acoustic signals produced by rutting males with changes in social context. (iv) Reveal the existence in this population of three rarely reported mating behaviours in polygynous mammals. I find around a fifth of females mate with the same male in multiple years; female relatives frequently mate with the same male; and males rut in locations close to their relatives. Further, I show these behaviours are associated with higher co-ancestry and inbreeding in the population than expected under random mating. (v) Finally, I investigate how spatial associations between relatives upwardly bias estimates of heritability in four phenotypic traits. I do this by accounting for shared environment effects in animal models by i) inclusion of spatial autocorrelation parameters and ii) a novel multi-matrix approach.
15

The influence of nutrition and photoperiod on the growth, development and endocrine status of captive red deer and Soay rams

Suttie, James Miller January 1981 (has links)
Scottish red deer (Cervus elaphus scoticus) are smaller in size and mature later than many continental subspecies. Previous investigations at the Rowett Institute have shown that when Scottish red deer are fed well they grow almost as large as European deer, so the differences between subspecies appear principally determined by the environment. To test this, one group of 6 stag calves was fed to appetite while a second group of 6 was offered 70% as much (on a metabolic body weight basis) during the winter and both groups fed to appetite during the following summer. After the first winter the restricted group were lighter and skeletally smaller than the unrestricted group. Despite compensatory growth during the summer significant differences in weight and size remained at the end of the period of feeding to appetite. This pattern was repeated during the second and third years of the study, Plane of nutrition bad little effect on size and composition of antlers but had profound effects on the timing of growth of the first antlers. Although the restricted stags were less fat than the unrestricted stags both groups showed the same relationship of fat content of the body to empty body weight. The restricted plane of nutrition delayed the growth and moult of wool and hair but did not affect length of either. The restricted plane of nutrition exerted only slight effects on levels of testosterone, oestradiol 17 beta,prolaotin and thyroriue and no effect on the timing of their cycles. A field study on the effect of winter undernutrition on stag calves at Glensaugh Deer Farm gave similar results. Cycles of body weight and food intake were shown to be of smalleramplitude in captive hinds than stage. Superior cervical ganglioneotomy of Soay rams diminished the amplitude of cycles of food intake and growth as much as cycles of reproduction but failed to abolish either.
16

Mammals in Late Neolithic Orkney (with reference to mammal bone recovered from Links of Noltland, Westray)

Fraser, Sheena Mary January 2015 (has links)
Excavation of thirty skulls, twenty-eight cattle and two sheep from the foundation course of a Late Neolithic structure at Links of Noltland (LON), Structure 9, is the starting point for this thesis, which investigates the economic and socio-cultural relationships of cattle and other mammals on Orkney communities between 3000 and 2500 BC. The LON settlement was located on a machair plain in Westray, the most N-W island within the Orkney archipelago (HY 428 493). Male and female cattle skulls were inter-mixed within the LON foundation course so a “bull cult” is not represented. The sequence from living skulls to skulls “animating the building is (i) breed/acquire (ii) nurture (iii) cull/butcher (iv) consume (v) transform to object (vi) curate (vii) deposit. A skull deposit infilling an internal passageway from another LON, Structure 18, is compared and contrasted with the Structure 9 foundation deposit. Special treatment of cattle skulls from a wide range of European and Near-East sites is also reviewed to emphasise the widespread use of this symbol during the Neolithic period. Orkney was separated from mainland Scotland prior to the establishment of the LON settlement so consideration is given to modes of arrival for mammals and their impact on this depauperate archipelago. Cattle and sheep dominated the domestic mammal remains examined, pig and dog were rare and goat and horse absent. The most abundant non-domestic mammals were red deer and Orkney voles, but otters and sea mammals were also present in low numbers. Genetic studies indicate that one cattle skull carried genetic material from aurochs, wild cattle. To date there is sparse evidence of interbreeding between wild aurochs and Neolithic domesticated cattle in Europe and none in Britain. The alterative explanation that aurochs were already present on Orkney during the Neolithic is explored. Articulated red deer deposits from LON were also examined. Although previous publications explored the possibility that these deposits are “ritual” other possible explanations for these deposits are outlined. No parallels were noted between the cattle skull and articulated red deer deposits, but the importance of antler for practical and symbolic use in Neolithic Orkney may be under-estimated. Stature of cattle remained relatively stable during the Mid to Late Neolithic in Orkney but underwent diminution by the Iron Age. A similar, but less marked reduction was also noted for sheep, but red deer already had small stature compared with early Holocene mainland Scotland red deer. The thesis concludes that cattle, sheep and red deer were of fundamental importance to the Neolithic society of Orkney, providing surplus food, tools and possibly traction, to support an increasingly sophisticated Neolithic society undertaking construction of complex structures and monuments. In addition, cattle fulfilled an important role in their cultural and spiritual life.
17

Linking environmental variation across the Scottish Highlands with red deer (Cervus elaphus) trace element status, parasite burden, and skeletal morphometry

French, Andrew Samuel January 2016 (has links)
No description available.
18

Roles, rights, and responsibilities in the sustainable management of red deer populations in Scotland

Witta, Lorin E. January 2018 (has links)
The aim of the project was to explore the acquisition and dissemination of knowledge amongst decision-makers involved in the management of red deer in Scotland. While research exists on the ecology of red deer habitat, no research exists that focuses on the relationship between the deer and the people responsible for their management. Therefore, this thesis is primarily qualitative research which aimed to explore the various aspects of red deer management in Scotland within the socio-ecological context in which it exists. There are numerous groups with interest in red deer management, however this research, due to scope and time restrictions, was limited to two primary groups, the individuals tasked with implementing policy and the practitioners who carry out culling. During the course of the project, under-researched topics surfaced, highlighting areas of practical and theoretical divergence between stakeholders. This thesis therefore aims to explore how differing views and perspectives of two of the key stakeholder groups – the estate-based practitioners (including stalkers, land-managers, and land-owners) and staff of governmental agencies – influence the management of red deer in Scotland. This research indicates that people with different roles hold different relationships with the deer, which affect management decisions and implementation at local, regional, and/or national level. As with other areas within conservation and wildlife management, this research indicates there is a disconnect between blanket governmental policy and site-specific needs, with a lack of inclusion of practitioner knowledge. Potential future research would include additional qualitative research to follow up some of the management issues raised by this research and formulate recommendations for changes to practice, followed by collection of quantitative data assessing the efficacy of interventions.
19

Hybridisation between red deer (Cervus elaphus) and Japanese sika (C. nippon) on the Kintyre Peninsula, Scotland

Senn, Helen V. January 2009 (has links)
Hybridisation between introduced and endemic species causes conservation concerns, but also provides us with an opportunity to study the dynamics of gene flow between two species as they first meet. Japanese sika deer (Cervus nippon) were introduced to the British Isles at a number of locations at the beginning of the 20th century. In the intervening time, sika have spread and their range now extends across approximately 40% of Scotland, where they overlap with that of native red deer (C. elaphus), with which they hybridise. In this study we focus on the consequences of one particular introduction that took place at Carradale, on the Kintyre Peninsula in 1893. First, I assessed the current state of hybridisation using a sample of 735 red and sika deer samples collected in 2006/7 from forestry blocks throughout the Kintyre Peninsula. Genetic analysis was conducted with a panel of 22 highly differentiated microsatellite loci and one mtDNA marker. Population admixture analysis of the microsatellite data was conducted with the Bayesian clustering programme STRUCTURE. Over most of the study area, levels of introgression into red and sika deer were low and were consistent with a scenario of very occasional F1 hybridisation followed by backcrossing. There was, however, one forestry block where 43% of individuals could be defined as hybrids. Second, I developed a branching process model of introgression via backcrossing, to assess whether variation in introgression across microsatellite loci could be interpreted as a signature of selection, or could in fact be attributed to stochastic processes. If only a few hybridisation events have contributed to the hybridising population, the pattern of introgression, even with a large number of genetic markers, will be highly stochastic. This pattern of neutral variation in introgression can have high enough variance that it could be mistaken for selection. Therefore, even if strong selection is acting, it may not be possible to distinguish its effects from neutral variation. Third, I analysed trends in hybridisation and introgression over 15 years on the peninsula, through analysis of a dataset of 1513 red and sika deer samples at 20 microsatellite and a mtDNA marker. There was little evidence of change in the extent of hybridisation and introgression over time. MtDNA introgression was predominantly from red deer into sika. Recent introgression into sika on the peninsula can be explained by a very small number of F1 hybridisation events (~10) via analysis of the number of alleles that have introgressed from polymorphic red deer into the genetically homogenous sika population (a similar analysis cannot be conducted for introgression into red deer). Finally, I conducted a regression analysis of genetic hybrid scores against phenotypic traits to assess the effect of hybridisation on phenotype. Hybridisation has caused changes in the weight of sika-like deer and red-like females. Hybridisation has caused changes in incisor arcade breadth of both populations and jaw length (a proxy for skeletal size) in sika-like females. However, there is no evidence that hybridisation has caused changes in kidney fat (a measure of condition) or pregnancy rates in either population. In conclusion, even a small number of F1 hybridisation events can lead to extensive introgression and the timing and spatial distribution of these events is likely to have a large impact on the structure of a recently hybridising population - stochastic factors dominate both the distribution of hybrid individuals and the distribution of the genes that introgress following a hybridisation event. In red deer and sika deer, increasing phenotypic similarities of the two populations caused by hybridisation are likely to facilitate further breakdown between the two species. It is possible that breakdown in assortative mating between the two species could occur across their range.
20

Red deer (Cervus elaphus) grazing on vegetation mosaics : grazing patterns and implications for conservation management

Moore, Emily Kathryn January 2015 (has links)
Grazing is widely used as a tool in conservation management. Many plant communities of conservation importance are dependent on grazing for their existence, maintenance of species diversity and other valued characteristics. Plant community response to grazing depends on many factors, including site productivity and dominant plant species; setting appropriate grazing levels can therefore be challenging. The problems are magnified when more than one species or plant community is the target of conservation goals as they may need different levels of grazing. Where multiple plant communities are present in a mosaic, grazing pressure on the higher productivity community (usually the more attractive to herbivores) can affect the utilisation of the lower productivity communities: grazing on the less productive community is elevated in close proximity (a few metres) to the productive community. This increases the possibility of conflict in managing grazing for the conservation of both communities as low productivity communities can sustain only low levels of grazing. Less well studied are the effect of community layout at larger spatial scales (100s – 1000s of metres) and the effect of vegetation pattern on grazing on the productive community. It is also not well known how the spatial pattern of grazing is affected by changes in herbivore density. I investigated the consequences of the spatial pattern of plant communities and changing herbivore density for grazing patterns on a complex multi-community mosaic and assessed the probable consequence for conservation of these plant communities. The plant mosaic comprised a mixture of species-rich grassland and several less productive communities, primarily heaths and bogs; the main grazers were red deer (Cervus elaphus). The grassland needs higher grazing levels than the others to meet management goals. I used small scale experiments to investigate the effects of reducing grazing on grassland and how the effects varied within the grassland community. Elimination of grazing caused a rapid switch from short, herb-rich grassland towards a graminoid dominated, less diverse sward, as expected. The degree of change in diversity and herb cover was dependent on productivity. Experimental reduction in grazing had mixed consequences for grassland in relation to conservation goals due to pre-existing variation in intensity of grazing on the grassland. The condition of areas of initially heavily grazed and short vegetation improved, whilst taller grasslands deteriorated. Analysis of large-scale datasets was used to investigate the influence of spatial pattern of community types and differences in large scale deer density on the distribution of grazing. There was increased grazing pressure on less productive plant communities where grassland was abundant within 1km and this was fairly consistent across communities and across different grazing indicators. There was an effect on grazing levels on grassland, but the explanatory power was generally lower and the effect less consistently present across indicators of grazing. Sward height and litter depth measures from one dataset indicated heavier grazing with more grassland present nearby (250m); however, lower grazing pressure was indicated by sward height and a combined grazing index when there was more grassland in a more distant zone (500-1000m). Deer density had limited power to explain large scale variation in impacts, probably due to the coarse scale of the information available and correlation with other variables. This limited the ability to thoroughly test the consequences of changes in deer density on the spatial pattern of impacts or investigate whether there was an interaction between deer density and spatial pattern. The inherent conflict in conservation management of grazed communities of different productivities is increased by the influence of the spatial distribution of plant communities on the distribution of grazing; conservation management goals need to account for this and identify a suitable trade-off.

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