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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.
111

Migration, dispersal, and survival patterns of mule deer (<i>Odocoileus hemionus</i>) in a chronic wasting disease-endemic area of southern Saskatchewan

Skelton, Nicole Kimberly 21 September 2010
Chronic wasting disease (CWD) has infected wild deer of Saskatchewan for at least the past 10 years. Disease management plans have evolved over the years, but without information on mule deer (<i>Odocoileus hemionus</i>) habits and movements in the grasslands of southern Saskatchewan. We radio-collared and monitored the survival and movements of 206 mule deer from 2006 to 2009. Long distance movements by deer have potential to transfer disease to previously naïve areas. Survival rates had not yet been evaluated in this area; baseline data will provide a useful measure for population-level impacts of the disease in the future.<p> Juvenile dispersals and adult migrations were contrasted from 4 study areas along the South Saskatchewan River. Dispersal distance (median = 22.8 km, n = 14) was similar to migration distance (median = 16.0 km, n = 49). Median migration distance was similar between males (15.7 km, n = 51) and females (19.7 km, n = 65). Obligatory migrants were more likely to be female. Deer from an area of extensive grassland were more likely to be migratory than their counterparts in fragmented grassland of an agricultural landscape. Maximum migration and dispersal distances were 113 km and 195 km, respectively. Movement paths of 33 GPS-collared deer were best explained by high terrain ruggedness values and proximity to grassland.<p> Seasonal survival rates showed that deer had lowest survival in autumn months during hunting season. Juveniles had lower survival than adults in all seasons. Harvest regime changes in 2008 improved the autumn survival of adult females but adult males had lower survival than in 2007. Body condition of captured deer was evaluated from residuals of mass-length regression. Cox regression analyses suggested that deer in good body condition (75th percentile) were half as likely to die and that those in very poor body condition (10th percentile) were twice as likely to die. Radio collars that weighed > 2% of body mass negatively affected survival and we recommend future researchers take this into consideration. <p> Survival, dispersal, and migration rates and patterns are crucial parameters in modeling CWD in local mule deer populations. Saskatchewan wildlife managers aim to prevent CWD spread into new areas, and can use mule deer movement orientations to target surveillance accordingly. White-tailed deer (<i>Odocoileus virginianus</i>) movements are briefly discussed; further knowledge of their movements is required for CWD management in all of Saskatchewan.
112

Migration, dispersal, and survival patterns of mule deer (<i>Odocoileus hemionus</i>) in a chronic wasting disease-endemic area of southern Saskatchewan

Skelton, Nicole Kimberly 21 September 2010 (has links)
Chronic wasting disease (CWD) has infected wild deer of Saskatchewan for at least the past 10 years. Disease management plans have evolved over the years, but without information on mule deer (<i>Odocoileus hemionus</i>) habits and movements in the grasslands of southern Saskatchewan. We radio-collared and monitored the survival and movements of 206 mule deer from 2006 to 2009. Long distance movements by deer have potential to transfer disease to previously naïve areas. Survival rates had not yet been evaluated in this area; baseline data will provide a useful measure for population-level impacts of the disease in the future.<p> Juvenile dispersals and adult migrations were contrasted from 4 study areas along the South Saskatchewan River. Dispersal distance (median = 22.8 km, n = 14) was similar to migration distance (median = 16.0 km, n = 49). Median migration distance was similar between males (15.7 km, n = 51) and females (19.7 km, n = 65). Obligatory migrants were more likely to be female. Deer from an area of extensive grassland were more likely to be migratory than their counterparts in fragmented grassland of an agricultural landscape. Maximum migration and dispersal distances were 113 km and 195 km, respectively. Movement paths of 33 GPS-collared deer were best explained by high terrain ruggedness values and proximity to grassland.<p> Seasonal survival rates showed that deer had lowest survival in autumn months during hunting season. Juveniles had lower survival than adults in all seasons. Harvest regime changes in 2008 improved the autumn survival of adult females but adult males had lower survival than in 2007. Body condition of captured deer was evaluated from residuals of mass-length regression. Cox regression analyses suggested that deer in good body condition (75th percentile) were half as likely to die and that those in very poor body condition (10th percentile) were twice as likely to die. Radio collars that weighed > 2% of body mass negatively affected survival and we recommend future researchers take this into consideration. <p> Survival, dispersal, and migration rates and patterns are crucial parameters in modeling CWD in local mule deer populations. Saskatchewan wildlife managers aim to prevent CWD spread into new areas, and can use mule deer movement orientations to target surveillance accordingly. White-tailed deer (<i>Odocoileus virginianus</i>) movements are briefly discussed; further knowledge of their movements is required for CWD management in all of Saskatchewan.
113

SOA and Quality

Peng, Qian, Fan, Yang Qing January 2008 (has links)
<p>This thesis emphasizes on investigating the relationship between the quality attributes and service oriented architecture (SOA). Due to quality attributes requirements drive the design of software architecture, it is necessary to maintain the positive quality of SOA and improve the negative quality of SOA. This thesis gives an introduction to SOA, Enterprise Service Bus (ESB) and MULE. Then, it covers information on quality of systems and tactics for achieving each quality attribute. Finally, we discuss the quality of SOA in detail, and illustrate how to set up a SOA and how to improve its quality using a case of an order for supermarket.</p> / Order system
114

Perspectives on prions : mapping the social landscape around chronic wasting disease on the Canadian prairies

2014 April 1900 (has links)
Social perspectives on natural resources management have become an increasingly valuable part of natural resources management decision making, especially at the policy or governance level. However, due to the range of social contexts that can exist around management questions, not every technique for incorporating stakeholders into management is suited for every management problem. My research examines the social landscape around chronic wasting disease (CWD) management on the Canadian prairies in order to identify a way forward for stakeholder involvement in CWD management. CWD is a prion disease that results in neurodegeneration and death in cervids. CWD has the potential for broad social impact because it infects elk and deer, species which are both hunted and ranched. Furthermore, management and monitoring efforts in free-ranging cervids frequently incorporate hunting activity. Q methodology was used to survey stakeholders in Saskatchewan and Manitoba and synthesize perspectives about stakeholder understanding of CWD as a problem and preferences for potential solutions. The perspectives that emerged emphasized the importance of increasing knowledge about CWD and a generalized trust in government management, coupled with a desire for stakeholder consultation under the auspices of government leadership. I found that CWD management may not be ready for stakeholder spearheaded management activity due to ambivalence and uncertainty among stakeholders, but stakeholder involvement in CWD management can still offer valuable insight for managers. This is especially notable in light of the recent loss of Saskatchewan’s CWD monitoring program.
115

LESSONS FROM SCENARIO PLANNING FOR WILDLIFE MANAGEMENT IN THE SOUTHWEST YUKON

2014 January 1900 (has links)
The southwest Yukon social-ecological system (SES) is marked by complex changes, including a climate induced directionally changing landscape, an increasing shift away from traditional subsistence lifestyles, and changing species composition. The addition of “new” ungulate species through human and non-human introductions has spawned many management questions. This study developed qualitative scenarios through a participatory process, utilizing scientific and traditional knowledge from within the social-ecological system’s local context. The study worked with local management groups to address two main objectives: 1.) Collaboratively envision alternate future scenarios with management groups from which to collaboratively develop management goals for wood bison, elk, and mule deer to cope with the changing social and ecological landscape of the southwest Yukon and 2.) Discover resource managers’ and local stakeholders’ perceptions of scenario planning as a method identify wildlife management goals. A series of three workshops with the Alsek Renewable Resource Council, the Yukon Wood Bison Technical Team, and the Yukon Elk Management Planning Team addressed the first objective, while two surveys addressed the second objective. Major findings included southwest Yukon-specific wildlife management goals and considerations for using scenario planning in a wildlife management context. The scenarios themselves warn of plausible events that might unfold, such as novel disease and pest outbreaks. Several participants mentioned that the value attributed to different species will change based on scenario context. This prompts warnings for wildlife managers not to “shut the door” on a species today that may be highly valuable for solving food security challenges of the future. Findings suggest that one of scenario planning’s most significant contribution is a forum for people to share perspectives and develop trust and understanding of one another. All participants valued the holistic and long-term thinking aspects of scenario planning, seeing it as a complementary tool to enhance existing planning processes. Major resource management plans and/or resource development projects in the future should consider using a scenarios approach to better articulated goals in terms of whole system impacts.
116

A mula (Equus mulus) como receptora de embriões equinos (Equus caballus) : aspectos reprodutivos, hormonais e ultrassonográficos da gestação

Camargo, Carlos Eduardo January 2018 (has links)
O Brasil é um dos países com o maior número de transferências de embriões de equinos do mundo, mas as éguas receptoras são escassas e caras. Uma alternativa é usar mulas acíclicas como receptoras de embriões equinos. O objetivo deste estudo foi comparar pela primeira vez o desenvolvimento embrionário e fetal precoce em mulas e éguas receptoras do 10º ao 60º dia de gestação. Este estudo foi realizado na Fazenda Experimental Gralha Azul da Pontifícia Universidade Católica do Paraná. Cinco éguas de doadores de embriões com idades entre 4 e 10 anos foram utilizadas. Foram utilizados dois grupos de receptores: 10 éguas cíclicas com idades entre 4 e 15 anos (grupo controle) e 7 mulas acíclicas com idades entre 6 e 12 anos. Os animais foram mantidos em piquetes e/ou estábulos e tiveram acesso a água e sal mineral ad libitum, bem como a uma fonte de volumoso e concentrado. As éguas doadoras foram monitoradas diariamente por ultrassonografia transretal (transdutor linear de 5 MHz, A6V Sonoscape, China) após o início do estro. As éguas foram inseminadas artificialmente usando sêmen fresco de um garanhão com fertilidade comprovada. A coleta de embriões das éguas foi realizada 8 dias após a ovulação. Antes da transferência do embrião, as éguas receptoras cíclicas eram examinadas diariamente por ultrassonografia para usar a melhor sincronia com a ovulação da doadora. As mulas acíclicas foram preparadas antes da transferência do embrião com a administração de 17 beta-estradiol (10 mg/mL, 1 mL, im) no dia da ovulação da doadora, e após 2 dias quando a presença de edema uterino foi confirmada, com a administração de Altrenogest (60 mg/mL, 5 mL, im). O diagnóstico de gestação foi realizado por ultrassonografia, 10 dias após a ovulação da doadora. Quando o diagnóstico foi confirmado, a avaliação ultrassonográfica foi realizada diariamente até o 60º dia de gestação. O primeiro dia de detecção da vesícula embrionária foi o Dia 10 por ultrassonografia em ambas as espécies e Dia 20,9 ± 1,3 (Média ± DP) e 21,9 ± 0,9 por palpação transretal em mulas e éguas respectivamente. A fixação da vesícula ocorreu em média no dia 15,7 ± 1,1 em mulas e 16,6 ± 1,7 em éguas. O embrião propriamente dito foi detectado pela primeira vez em mulas (no dia 19,9 ± 1,1) em comparação com as éguas (20,4 ± 1,3). O batimento cardíaco foi observado posteriormente em muares (23,4 ± 1,4) do que em éguas (22,6 ± 0,8). O saco alantóide foi detectado pela primeira vez entre os dias 23 e 26 (25,3 ± 1,1 e 24,6 ± 1,0 em mulas e éguas, respectivamente) e o cordão umbilical foi detectado pela primeira vez no dia 39 (39,7 ± 2,1 x 39,6 ± 1,5 em mulas e éguas, respectivamente). Os diâmetros ovarianos para os ovários esquerdo e direito foram semelhantes para as mulas (21,4 ± 0,4 vs. 21,8 ± 0,4 mm) e para as éguas (45,1 ± 0,4 vs 46,0 ± 0,4). Entretanto, o diâmetro ovariano das éguas (45,5 ± 0,3 mm) foi duas vezes maior (P <0,0001) que as mulas (21,6 ± 0,3 mm). Apenas duas mulas apresentaram o CL acessório que foi observado pela primeira vez nos dias 49 e 51. Dentro dos grupos não houve diferenças entre os cornos esquerdo e direito, gravídicos e não-gravídicos. A média geral não foi diferente entre as mulas (24,6 ± 3,1 mm) e as éguas (25,4 ± 0,1 mm). Como conclusão, de acordo com o nosso conhecimento, este é o primeiro estudo comparativo sobre desenvolvimento embrionário e fetal precoce entre mulas acíclicas e éguas receptoras de embriões equinos. Numerosas semelhanças foram encontradas nos aspectos estudados. Tais achados, associados ao fato de que potros vivos e sadios foram produzidos, sugerem que o uso de mulas acíclicas pode ser considerado como uma alternativa para aumentar a disponibilidade de receptoras em programas equinos de TE. / Brazil is one of the countries with the largest number of equine embryo transfers in the world, but recipients mares are scarce and expensive. One alternative is to use acyclic mules as recipients for equine embryos. The aim of this study was to compare for the first time the embryonic and early fetal development in recipient mules and mares from day 10 to 60 of pregnancy. This study was conducted at the Experimental Farm Gralha Azul of the Pontifical Catholic University of Paraná. Five embryo donor mares aged 4 to 10 years were used. Two groups of recipients were used: 10 cyclic mares aged 4 to 15 years (control group), and 7 acyclic mules aged 6 to 12 years. Animals were kept in paddocks and/or stables and had access to water and mineral salt ad libitum, as well as to a source of roughage and concentrate. Donor mares were monitored daily by transrectal ultrasonography (5-MHz linear transducer, A6V Sonoscape, China) after the beginning of estrus. The mares were artificially inseminated using fresh semen from a stallion with proven fertility. Embryo collection from the mares was performed 8 days after ovulation. Before embryo transfer, cyclic recipient mares were examined daily by ultrasonography to use the most synchronous with the donor's ovulation and have not received any hormonal treatment. The acyclic mules were prepared before the embryo transfer with the administration of 17 beta-estradiol (10 mg/mL, 1 mL, i.m.) on the day of the donor's ovulation, and after 2 days when the presence of uterine edema was confirmed, with the administration of Altrenogest (60 mg/mL, 5 mL, i.m.). The pregnancy diagnosis was carried out by ultrasonography 10 days after ovulation in the donor. When the diagnosis was confirmed, ultrasonographic assessment was carried out daily until day 60 of pregnancy. The first day of detection of an embryonic vesicle was Day 10 by ultrasound in both species and day 20.9 ± 1.3 (Mean ±SD), and 21.9 ± 0.9 by transrectal palpation in mules and mares respectively. Fixation of the vesicle occurred on mean day 15.7 ± 1.1 in mules and 16.6 ± 1.7 in mares. The embryo proper was first detected in mules (on day 19.9 ± 1.1) compared to mares (20.4 ± 1.3) The heart beat was observed later in mules (23.4 ± 1.4) than in mares (22.6 ± 0.8). The allantoic sac was first detected between days 23 and 26 (25.3 ± 1.1 and 24.6 ± 1.0 in mules and mares, respectively) and the umbilical cord was first detected on day 39 (39.7 ± 2.1 x 39.6 ± 1.5 in mules and mares, respectively). The ovarian diameters for left and right ovaries were similar for mules (21.4 ± 0.4 vs. 21.8 ± 0.4 mm) and for mares (45.1 ± 0.4 vs. 46.0 ± 0.4). However, the ovarian diameter of the mares (45.5 ± 0.3 mm) was two times larger (P<0.0001) than the mules (21.6 ± 0.3 mm). Within groups there were no differences between left and right and gravid and non-gravid horns. Data were combined for comparison of the endometrial diameter between mules and mares. The overall mean was not different between mules (24.6 3.1 ± 0.1 mm) and mares (25.4 ± 0.1 mm). However, day (P<0.003) and group-by-day (P<0.0001) effects were detected. Only two mules presented accessory CL that was observed for the first time on days 49 e 51. In conclusion, to the best of our knowledge, this is the first comparative study on embryo and early fetal development between noncycling mules and mares used as ET recipients of horse-horse embryos. Numerous similarities in embryo and early fetal development, and endocrinology aspects were seen. The findings of this study in mules, associated with the fact that alive and healthy offspring were produced, the use of mules may be considered as an alternative to increase the availability of recipients in equine ET programs.
117

A mula (Equus mulus) como receptora de embriões equinos (Equus caballus) : aspectos reprodutivos, hormonais e ultrassonográficos da gestação

Camargo, Carlos Eduardo January 2018 (has links)
O Brasil é um dos países com o maior número de transferências de embriões de equinos do mundo, mas as éguas receptoras são escassas e caras. Uma alternativa é usar mulas acíclicas como receptoras de embriões equinos. O objetivo deste estudo foi comparar pela primeira vez o desenvolvimento embrionário e fetal precoce em mulas e éguas receptoras do 10º ao 60º dia de gestação. Este estudo foi realizado na Fazenda Experimental Gralha Azul da Pontifícia Universidade Católica do Paraná. Cinco éguas de doadores de embriões com idades entre 4 e 10 anos foram utilizadas. Foram utilizados dois grupos de receptores: 10 éguas cíclicas com idades entre 4 e 15 anos (grupo controle) e 7 mulas acíclicas com idades entre 6 e 12 anos. Os animais foram mantidos em piquetes e/ou estábulos e tiveram acesso a água e sal mineral ad libitum, bem como a uma fonte de volumoso e concentrado. As éguas doadoras foram monitoradas diariamente por ultrassonografia transretal (transdutor linear de 5 MHz, A6V Sonoscape, China) após o início do estro. As éguas foram inseminadas artificialmente usando sêmen fresco de um garanhão com fertilidade comprovada. A coleta de embriões das éguas foi realizada 8 dias após a ovulação. Antes da transferência do embrião, as éguas receptoras cíclicas eram examinadas diariamente por ultrassonografia para usar a melhor sincronia com a ovulação da doadora. As mulas acíclicas foram preparadas antes da transferência do embrião com a administração de 17 beta-estradiol (10 mg/mL, 1 mL, im) no dia da ovulação da doadora, e após 2 dias quando a presença de edema uterino foi confirmada, com a administração de Altrenogest (60 mg/mL, 5 mL, im). O diagnóstico de gestação foi realizado por ultrassonografia, 10 dias após a ovulação da doadora. Quando o diagnóstico foi confirmado, a avaliação ultrassonográfica foi realizada diariamente até o 60º dia de gestação. O primeiro dia de detecção da vesícula embrionária foi o Dia 10 por ultrassonografia em ambas as espécies e Dia 20,9 ± 1,3 (Média ± DP) e 21,9 ± 0,9 por palpação transretal em mulas e éguas respectivamente. A fixação da vesícula ocorreu em média no dia 15,7 ± 1,1 em mulas e 16,6 ± 1,7 em éguas. O embrião propriamente dito foi detectado pela primeira vez em mulas (no dia 19,9 ± 1,1) em comparação com as éguas (20,4 ± 1,3). O batimento cardíaco foi observado posteriormente em muares (23,4 ± 1,4) do que em éguas (22,6 ± 0,8). O saco alantóide foi detectado pela primeira vez entre os dias 23 e 26 (25,3 ± 1,1 e 24,6 ± 1,0 em mulas e éguas, respectivamente) e o cordão umbilical foi detectado pela primeira vez no dia 39 (39,7 ± 2,1 x 39,6 ± 1,5 em mulas e éguas, respectivamente). Os diâmetros ovarianos para os ovários esquerdo e direito foram semelhantes para as mulas (21,4 ± 0,4 vs. 21,8 ± 0,4 mm) e para as éguas (45,1 ± 0,4 vs 46,0 ± 0,4). Entretanto, o diâmetro ovariano das éguas (45,5 ± 0,3 mm) foi duas vezes maior (P <0,0001) que as mulas (21,6 ± 0,3 mm). Apenas duas mulas apresentaram o CL acessório que foi observado pela primeira vez nos dias 49 e 51. Dentro dos grupos não houve diferenças entre os cornos esquerdo e direito, gravídicos e não-gravídicos. A média geral não foi diferente entre as mulas (24,6 ± 3,1 mm) e as éguas (25,4 ± 0,1 mm). Como conclusão, de acordo com o nosso conhecimento, este é o primeiro estudo comparativo sobre desenvolvimento embrionário e fetal precoce entre mulas acíclicas e éguas receptoras de embriões equinos. Numerosas semelhanças foram encontradas nos aspectos estudados. Tais achados, associados ao fato de que potros vivos e sadios foram produzidos, sugerem que o uso de mulas acíclicas pode ser considerado como uma alternativa para aumentar a disponibilidade de receptoras em programas equinos de TE. / Brazil is one of the countries with the largest number of equine embryo transfers in the world, but recipients mares are scarce and expensive. One alternative is to use acyclic mules as recipients for equine embryos. The aim of this study was to compare for the first time the embryonic and early fetal development in recipient mules and mares from day 10 to 60 of pregnancy. This study was conducted at the Experimental Farm Gralha Azul of the Pontifical Catholic University of Paraná. Five embryo donor mares aged 4 to 10 years were used. Two groups of recipients were used: 10 cyclic mares aged 4 to 15 years (control group), and 7 acyclic mules aged 6 to 12 years. Animals were kept in paddocks and/or stables and had access to water and mineral salt ad libitum, as well as to a source of roughage and concentrate. Donor mares were monitored daily by transrectal ultrasonography (5-MHz linear transducer, A6V Sonoscape, China) after the beginning of estrus. The mares were artificially inseminated using fresh semen from a stallion with proven fertility. Embryo collection from the mares was performed 8 days after ovulation. Before embryo transfer, cyclic recipient mares were examined daily by ultrasonography to use the most synchronous with the donor's ovulation and have not received any hormonal treatment. The acyclic mules were prepared before the embryo transfer with the administration of 17 beta-estradiol (10 mg/mL, 1 mL, i.m.) on the day of the donor's ovulation, and after 2 days when the presence of uterine edema was confirmed, with the administration of Altrenogest (60 mg/mL, 5 mL, i.m.). The pregnancy diagnosis was carried out by ultrasonography 10 days after ovulation in the donor. When the diagnosis was confirmed, ultrasonographic assessment was carried out daily until day 60 of pregnancy. The first day of detection of an embryonic vesicle was Day 10 by ultrasound in both species and day 20.9 ± 1.3 (Mean ±SD), and 21.9 ± 0.9 by transrectal palpation in mules and mares respectively. Fixation of the vesicle occurred on mean day 15.7 ± 1.1 in mules and 16.6 ± 1.7 in mares. The embryo proper was first detected in mules (on day 19.9 ± 1.1) compared to mares (20.4 ± 1.3) The heart beat was observed later in mules (23.4 ± 1.4) than in mares (22.6 ± 0.8). The allantoic sac was first detected between days 23 and 26 (25.3 ± 1.1 and 24.6 ± 1.0 in mules and mares, respectively) and the umbilical cord was first detected on day 39 (39.7 ± 2.1 x 39.6 ± 1.5 in mules and mares, respectively). The ovarian diameters for left and right ovaries were similar for mules (21.4 ± 0.4 vs. 21.8 ± 0.4 mm) and for mares (45.1 ± 0.4 vs. 46.0 ± 0.4). However, the ovarian diameter of the mares (45.5 ± 0.3 mm) was two times larger (P<0.0001) than the mules (21.6 ± 0.3 mm). Within groups there were no differences between left and right and gravid and non-gravid horns. Data were combined for comparison of the endometrial diameter between mules and mares. The overall mean was not different between mules (24.6 3.1 ± 0.1 mm) and mares (25.4 ± 0.1 mm). However, day (P<0.003) and group-by-day (P<0.0001) effects were detected. Only two mules presented accessory CL that was observed for the first time on days 49 e 51. In conclusion, to the best of our knowledge, this is the first comparative study on embryo and early fetal development between noncycling mules and mares used as ET recipients of horse-horse embryos. Numerous similarities in embryo and early fetal development, and endocrinology aspects were seen. The findings of this study in mules, associated with the fact that alive and healthy offspring were produced, the use of mules may be considered as an alternative to increase the availability of recipients in equine ET programs.
118

The effects of hunting and seral succession upon Vancouver Island black-tailed deer

Smith, Ian Donaldson January 1968 (has links)
The role of seral succession and hunting in the regulation of Vancouver Island black-tailed deer populations (Odocoileus hemionus columbianus, Richardson) was studied from comparison of observed changes in the Northwest Bay herd over the period 1954-1966 with those predicted from a computer simulation of population processes of such a herd. Northwest Bay was chosen because there were accurate logging records since the first cut was made in 1939, and accurate kill records since hunters were first allowed into the area in appreciable numbers in 1954. Previous studies had shown that deer populations increase rapidly after fire and logging, but tend to return to former levels 15 to 20 years later. Indices of range condition were calculated by multiplying the number of square miles of land in certain seral stages by the number of deer per square mile expected to occupy each stage (as determined by previous studies). Over the period 1956-1966 the Northwest Bay area was in decline as deer habitat, while hunting pressure increased. Two independent indices suggested that deer numbers declined over this period, in association with a decline in condition (measured by weight in fall) of the younger age-classes of males. Average weights of the lower age-classes of females followed similar patterns, but the decreases in weight were not significant—perhaps because of inadequate samples. These changes supported the hypothesis that seral succession is the most important long-range determinant of deer numbers, but one expected change (the development of an older average age) was not found. The proportion of 1.5-year-old animals increased and decreased in cyclic fashion over the period 1954-1966, but no consistent trend towards an older or younger age-class structure was observed when the period 1954-1959 was compared with the period 1960-1966. The absence of such a change was attributed to the effects of hunting, which would be expected to produce a younger average age if significant numbers of animals were harvested, and thus counteract the effects of a deteriorating habitat. In the years of heaviest hunting mortality (1962 and 1963 ) hunters probably accounted for 15 per cent of the fall population as a whole, and over 20 per cent of the fall male population. These levels of exploitation apparently resulted in significant declines in numbers of animals after both of these years, which supported the hypothesis that hunting can serve as a regulatory mechanism to maintain numbers within the limits determined by seral succession. Further support for this viewpoint came from the fact that year-to-year fluctuations in numbers, which were apparently great in the period 1954-1962, appeared to be dampened over the last four years of the study—a result which was predicted by computer simulation. A second major direct cause of mortality over the period 1954-1966 was believed to be winter weather. Significant declines in both numbers of animals and condition of males after the 1955-56 winter, which according to temperature and snowfall records was more severe than normal. There is reason to believe that this winter also resulted in disproportionately-high mortality among female fawns and 1.5-year-olds, but sample sizes were too small to permit adequate assessment of this point. A second winter, 1964-65, which was believed to have affected many Vancouver Island deer herds adversely and which was more severe than normal according to temperature and snowfall indices, had negligible effects upon the Northwest Bay deer. This may have been because, by this time, numbers had been reduced by hunting to levels that the area could effectively support even in a severe winter. One paradox was found, however. Hunting patterns resulted in males being shot in proportionately greater numbers than females, and in latter years this difference was apparently great enough to reduce the proportion of adult males. However, no corresponding significant change in the pattern of differences in male and female age-class structure was observed. Computer simulation of Northwest Bay population processes (not including fawns during the first two months of life) indicated that natural mortality from accident, predation, disease and other miscellaneous causes excluding winter loss associated with malnutrition was approximately 10 per cent of the herd every six months. It was concluded that seral succession had been the indirect cause of the decline in numbers of Northwest Bay deer over the period 1954-1966, but that numbers of animals in any year during the period 1954-1961 were dependent upon the severity of the winter, while following this time year-to-year population levels were dependent primarily upon the effects of hunting. / Science, Faculty of / Zoology, Department of / Graduate
119

Seasonal movements of black-tailed deer on northern Vancouver Island

Harestad, Alton Sidney January 1979 (has links)
Columbian black-tailed deer (Qdocoileus hemionug cplumbianus Richardson) were radio-tagged in a deep snowfall region on northern Vancouver Island, British Columbia. These deer were monitored to determine seasonal movements and habitat use. Deer exhibited either resident or migratory movement patterns. Resident deer made seasonal shifts in their home range centres but their seasonal home ranges overlapped. In migratory deer, summer home ranges were separated from both spring and winter home ranges, although their spring and winter home ranges overlapped. Altitudinal migrations occurred by deer moving between high and low elevation habitats. Horizontal migrations occurred by deer moving between a small tributary valley and the main valley. Seasonal movements of black-tailed deer result from habitat selection by deer seasonally moving to more favourable habitats as determined by more available energy and nutrients, and lower risk of predation. The causal differences between vertical and horizontal migrations as well as seasonal shifts in home range centres can be resolved by a model of habitat selection based on these factors. The densities of available digestible dry matter in Amabilis Fir - Twisted Stalk, and Mountain Hemlock - Copperbush associations are comparable with those in the shrub and conifer serai stages. This abundance of deer food in high elevation habitats suggests that forest harvesting in high elevations will not affect deer populations, if their other habitat requirements are met. In areas where forested summer ranges already exist, low elevation logging of Sword Fern - Western Red Cedar, Deer Fern - Western Hemlock, and Western Hemlock - Plagiothecium associations will provide deer with sources of abundant food closer to their winter ranges than the high elevation summer ranges. Use of these food sources may result in only a redistribution and not an increase in the deer population. Logging of Amabilis Fir - Western Hemlock, Salal - Douglas-fir, and Salal - Western Hemlock associations may be detrimental to deer populations because of their need for these habitats during winter. Management policies emphasizing preservation of severe winter range could be detrimental to deer populations. Habitat management for black-tailed deer must include provision of mild winter range as well as severe winter range. Because mild winter range provides deer with greater amounts of available energy and nutrients, it may be as important to the over-winter survival of deer as is severe winter range. The mobility of black-tailed deer and their sensitivity to snow suggest that few deer would be trapped in high elevations by early snowfalls. Corridors joining high and low elevations appear unnecessary to facilitate deer migrations. / Forestry, Faculty of / Graduate
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Boundaries and Bridges in Rangeland Social-Ecological Systems: Studies of Collaboration, Innovation, and Information Flow

Meredith, Gwendŵr R. 01 December 2019 (has links)
Public rangelands are managed by a mixture of federal, state, and local governments. Often, these groups are charged with managing adjacent lands that are part of the same greater landscape. To do this effectively, communication and collaboration is required. This dissertation examines federal, state, and local agencies’ level of communication through three projects. The first project examined barriers to agencies adopting management tools from each other. I found that individuals within agencies were mainly staying within their own agency when seeking advice, so individuals were not communicating about tools or their findings across agencies. Furthermore, agency policies and fear of being sued restricted individuals’ ability to adopt management tools. The second project studied how land and wildlife managers in Southeastern Utah work together, or not, in managing mule deer populations that migrate to and from land managed by different agencies. I found that managers are working together to manage mule deer populations, but there are only a few individuals that tie everyone together. The third project looked at how federal, state, and local governments work together to rehabilitate lands after a wildfire that burned parts of Southwestern Idaho and Southeastern Oregon. I found that policy decisions at the federal level can heavily impact who works together and when. All three projects revealed that there are still barriers to federal, state, and local governments working together to manage the same landscape. However, the results from this dissertation also highlight opportunities for bridging the gap between agencies and, ultimately, improving management of rangelands.

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