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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

Impacts of oil and gas development on sharp-tailed grouse on the Little Missouri National Grasslands, North Dakota /

Williamson, Ryan M. January 2009 (has links) (PDF)
Thesis (M.S.)--Wildlife and Fisheries Sciences Dept., South Dakota State University, 2009. / Includes bibliographical references (leaves 91-100). Also available via the World Wide Web.
112

Resursen orrspel : En studie om kunskap och möjligheter för orrspelsguidning, generellt och specifikt vid turistanläggningen Granö beckasin

Bergman, Tobias January 2018 (has links)
The aim of this report was to investigate how much people in general know about the bird black grouse and the possibilities for guiding on black grouse lek. I wanted to know how the possibilities where generally and specific at the tourist-facility Granö beckasin, which is situated in municipality of Vindeln in north of Sweden. I also wanted to get a better understanding about how the black grouse lek works and how the guiding would be best performed. Two different questionnaires were laid out, one with aim to reach a wide public and discover the knowledge and interest among people in general about black grouse lek. The aim with the second questionnaire was to reach people who is interested in bird- watching and get more quality answers about guiding on black grouse lek. While the questionnaires were collecting answers, market research about guiding and investigation of black grouse lekking spots possible for guiding around Granö was done. Most of the participants in the questionnaires showed a high level of awareness when it came to know what black grouse lek is, the majority also describe an active outdoorlife. The study showed a high level of black grouse lekking spots around Granö. Research and questionnaires showed that the target group for this type of guiding is small. The people in target for the type of guiding have big interest for birds and nature but doesn´t always have the time to research black grouse lekking spots themselves, therefore could a guide be helpful.
113

Birds of prey and grouse in Finland:do avian predators limit or regulate their prey numbers?

Reif, V. (Vitali) 28 May 2008 (has links)
Abstract Relationships between predators and prey may affect population dynamics of both parties. Predators may also serve as a link between populations of different prey, e.g., small game and small mammals. I used available data on the diet and reproduction of birds of prey (mainly common buzzards Buteo buteo and goshawks Accipiter gentilis) and video surveillance of their nests, as well as multiannual data on numbers of grouse and small mammals for studying food habits and population dynamics of raptors and their links with population fluctuations of voles and grouse (capercaillie Tetrao urogallus, black grouse Tetrao tetrix and hazel grouse Bonasa bonasia) in western Finland during 1980–1990s when grouse and vole numbers fluctuated in regular cycles. Microtus voles were the main prey of the buzzards which partly switched their diet to small game (juvenile grouse and hares) in years when vole numbers declined. The nesting rate of buzzards also correlated with vole abundance, but the productivity rate and brood size tended to lag behind the vole cycle. This mismatch between the buzzards' functional and numerical responses resulted in a fairly small impact of buzzards on juvenile grouse, which did not correlate with vole density. The productivity of goshawks followed the fluctuations of grouse density closely whereas the occupancy rate of goshawk territories did so with a two-year lag. The annual numerical ratio of goshawk to grouse was inversely related to grouse density, suggesting that this predator may be a destabilising factor for grouse population dynamics. However, the goshawks' kill rate of grouse showed no clear relations to grouse density. In June–July, these birds of prey (including hen harriers Circus cyaneus) usually killed a relatively small number of grouse chicks. Losses to raptors constituted up to one quarter of grouse juvenile mortality during the two months. We did not find a strong effect of avian predators on grouse juvenile mortality. In boreal forests, predators and other factors of grouse mortality do not operate as one, and there is probably no single factor responsible for the reproductive success of grouse.
114

Factors affecting the demography of a lek-mating bird: the greater prairie-chicken

Nooker, Jacqueline Kay January 1900 (has links)
Doctor of Philosophy / Department of Biology / Brett K. Sandercock / Sexual selection via female choice and male-male aggression leads to elaboration of male traits. If male traits correlated with reproductive success are honest signals of male quality, survival costs may be associated with the expression of those traits. Testosterone (hereafter ‘T’) may enhance male breeding success, but T can also reduce immunocompetence and survival. Socially monogamous male birds with higher circulating T experience reproductive advantages, but the role of T in lek mating systems is largely unknown. To address these issues, I individually marked and conducted focal behavioral observations of greater prairie-chickens (Tympanuchus cupido) at five lek sites over a 5-year period. Females were fitted with radio-telemetry to monitor nesting success and survival. I examined the relationship between male traits and mating success using multinomial discrete choice models, a statistical method not previously applied to studies of sexual selection. Male mating success was highly skewed at greater prairie-chicken leks with 18.5% of males obtaining 87.2% of all successful copulations (n = 108 males; 85 copulations). Mating success was influenced most by male behavior, followed by several morphological attributes. The role of T was quantified using blood samples and by experimentally implanting a subset of males with T. T did not consistently affect mating success. Non-territorial males had lower T levels than territorial males. Among territory holders, T was unexpectedly negatively correlated with mating success. However, the odds of receiving a copulation were 4.3 times (0.42 to 45.3) greater for T-implanted males than males with sham implants. Future work should explore the interactions among the immune system, parasite load, and mating success of prairie-chickens. Annual survival of male prairie-chickens was not related to mating success, behavior, age or T level, suggesting there is no cost of increased male mating success. Like males, reproductive success of females was also highly skewed because < 10% of nests successfully hatched young. Comparisons of seasonal and annual survival rates indicate that females experience increased mortality during the breeding season relative to the nonbreeding season. Synthesis of field estimates of demographic parameters indicates prairie-chicken populations will decline without changes in rangeland management to reduce predator numbers or provide more nesting cover.
115

Movements and Space-Use of Female Greater Sage-Grouse (Centrocercus urophasianus) During Nesting and Breeding Seasons

Retherford, Drew W 25 November 2020 (has links)
Greater sage-grouse (Centrocercus urophasianus) are a species of conservation concern throughout their range including the state of Idaho. Little is known about the size of areas used by female sage-grouse during the breeding and nesting seasons, fidelity of females to those areas, or fidelity of female sage-grouse to specific leks or nest sites. The recent miniaturization of global positioning system (GPS) transmitting devices allows for a more thorough analysis of this behavior. We placed GPS transmitters on 234 female sage-grouse in Idaho, USA, from 2015 to 2019. We monitored 145 nest attempts, 15 of which occurred in consecutive years, from 130 female sage-grouse (Centrocercus urophasianus) with GPS transmitters to document movements and space-use during nesting. We quantified the length and direction of off-nest excursion distances for all 145 nest attempts. Also, for the 15 consecutive nest attempts, we compared the excursion distances for each bird, each year. The mean distance for an off-nest excursion across all study areas was 93.7 m (n = 145, SD = 57.9, range = 15.5 to 275.8 m). Rayleigh’s test of uniformity indicated that eight of 145 nest attempts had off-nest excursions that were not in a consistent direction. Mean excursion distances in the consecutive year were longer than those of the initial year (T = -3.1, n = 15, p-value = 0.013), and females with smaller excursion distances in the initial year also had smaller excursion distances in the consecutive year. We also quantified size of breeding areas for 50 female sage-grouse and identified factors that influenced breeding-area size. For 18 of those females, we quantified size and fidelity to breeding areas and leks between successive years. We generated 95% brownian bridge estimates of breeding-area size for each bird and counted the number of leks those females visited. To quantify breeding-area fidelity for the 18 females, we overlaid 95% brownian bridge estimates for females with consecutive breeding attempts, calculated percent overlap, and documented number of leks visited each year. Median size of breeding areas for all females was 21 km2 (interquartile range = 7.8 to 59.3 km2). Each bird visited a mean of 2 leks (SD = 1.2, range = 1 to 6 leks). Between years, breeding areas overlapped for all 18 females, and size of breeding areas did not differ between the first and second year (W-value = 61, p-value = 0.49). For those 18 females, only 7 visited the same lek in consecutive years, and none visited more than one common lek in consecutive years. Our results indicate that females use large areas while breeding and nesting and exhibit strong fidelity to those areas. Our results provide novel information on the breeding and nesting ecology of this species that will help agencies that manage sage-grouse and their habitat.
116

A Study of the Relationship Between Plains Sharp-Tailed Grouse Nest Site Selection and Survival and Ecological Site Descriptions in the Northern Plains

Klostermeier, Derek Wade January 2019 (has links)
Nest site selection and nesting success of plains sharp-tailed grouse were examined on the Grand River National Grassland in South Dakota during the nesting season from 2009-2012. We used conditional logistic regression to assess vegetation production, ecological site description, and landscape position on nest site selection. Two competing models regarding nest site selection: top model consisted of non-native forbs and native cool-season grasses, second best model included all grass and forb. Nine ESDs were used for nesting; loamy and clayey ecological sites most frequently used and produced the highest standing crop. Most frequent observed nest site State were Annual/Pioneer Perennial and Introduced and Invaded Grass. Top model for nest daily survival rates included litter, second-best model included ESD; second-best model showed negative effect for nests initiated in thin claypan, limy backslope, and sandy ecological sites. Based on daily survival estimate and 23-day incubation period, nests were 59% successful.
117

Willow grouse (Lagopus lagopus) and rock ptarmigan (Lagopus muta) bag statistics and hunting pressure in Jämtland, Sweden : Relationships between CPUE, hunting pressure, different permits and nationality in two time periods; 2004-2012 and 2013-2021.

Kwanruen, Pattranit January 2022 (has links)
Willow grouse ( Lagopus lagopus) and rock ptarmigan (Lagopus muta) are popular game birds in Sweden. I have analysed hunting statistics from Jämtland county in Sweden and investigated if there is a significant correlation between willow grouse density and Catch-Per-Unit-Effort (CPUE) by nationalities and type of permits. The included nationalities were Swedish, Nordic and non-Nordic hunters. Type of permits that were analysed were day-, municipality and county permits. There was no correlation between the grouse density and CPUE variables. However, significant correlations were found when correlating yearly number of harvested grouse  with the CPUE variables. For willow grouse, significant correlations were found between Swedish, Non-Nordic, day and municipality permit hunters and for rock ptarmigan, Swedish, Nordic, day and municipality permit hunters. I also found that international hunters was more effective than Swedish hunters, as well as hunters with day permit, which was true for both species. There were also differences between the CPUE variables between two time periods, 2004-2012 and 2013-2021. In the second period, the CPUE of Swedish hunters, day and municipality permit hunters have decreased for willow grouse. The CPUE also decreased for non-Nordic during the second period for rock ptarmigans. Significant difference in hunting pressure were also found between the two time periods, where the later period had slightly higher hunting pressure than the first period. The results of this study strengthened previous studies where no correlation has been found between the grouse density and CPUE.
118

Vital Rates, Population Trends, and Habitat-Use Patterns of a Translocated Greater Sage-Grouse Population: Implications for Future Translocations

Duvuvuei, Orrin V. 01 May 2013 (has links)
Translocations have been used as a management strategy to successfully augment declining native wildlife populations. Greater sage-grouse (Centrocercus urophasianus; sage-grouse) population declines on Anthro Mountain, Utah prompted managers to translocate sage-grouse and test protocols from a successful translocation project in Strawberry Valley, Utah. Sage-grouse from Parker Mountain, Utah were used as the source population for Anthro Mountain and Strawberry Valley translocations. Sixty hens were translocated to Anthro Mountain in 2009 and 2010; I monitored vital rates of the 60 translocated hens and 32 resident hens from 2009-2012. My objective was to determine the overall success of the translocation 4 years after the initial release and compare vital rates to the source population and Strawberry Valley.In Chapter 2, I determined that survival varied by study area and hen age but was not affected by residency status. Annual survival of Anthro Mountain hens was lower than Parker Mountain and Strawberry Valley hens. Adult hen survival in all three populations was higher than yearling survival.In Chapter 3, I determined that the translocation contributed to population growth. Adult resident and previously translocated hens had the highest reproductive success, followed by resident yearlings, newly translocated adults, and newly translocated yearlings. Lek counts increased from 2009-2013 and a new lek was discovered in 2011. Survival was not affected by residency status or age, but varied greatly by year and season. Mean monthly survival was lowest in the fall; this differs from range-wide trends.In Chapter 4, I determined that translocated hens adapted to the release area. They exhibited similar seasonal movements and used similar habitats as residents. The home range size of resident and translocated hens was comparable; however, previously translocated hens had smaller home ranges than newly released hens.Despite landscape level differences between the source and release areas, translocated hens assimilated to the population and contributed to population growth. Although the translocation was successful, the low vital rate estimates are cause for concern. The low estimates suggest that factors such as predation, habitat quality and quantity, and anthropogenic influences may be problematic for this isolated population.
119

Factors Affecting Greater Sage-Grouse (Centrocercus Urophasianus) Survival and Movement in South-Central Utah

Caudill, Danny 01 May 2011 (has links)
Greater sage-grouse (Centrocercus urophasianus) adult and juvenile survival have been identified as critical demographic parameters. However, little is known regarding the dynamics of juvenile sage-grouse. From 2008-2010, I used radio-telemetry and 2 transmitter types to monitor 91 juvenile sage-grouse. Program MARK was used to analyze survival data. Over-winter survival was 0.802 - 0.982 and 0.687 - 0.969 for females and males, respectively. Fall survival rates were 0.522 - 0.623 for females and 0.332 - 0.449 for males. Survival from fall through winter was 0.418 - 0.616 for females and 0.228 - 0.435 for males. For both years combined, the probability predation caused death was 0.705, and probability harvest caused death was 0.159. The probability unreported harvest caused death was 0.091. Sex (p= 0.103) and transmitter type (p = 0.09) affected survival. Back-mounted transmitters negatively affected survival and their use should be avoided to minimize experimental bias.
120

Factors Affecting Gunnison Sage-Grouse (<i>Centrocercus minimus</i>) Conservation in San Juan County, Utah

Prather, Phoebe R. 01 December 2010 (has links)
Due to loss of habitat, Gunnison sage-grouse (Centrocercus minimus) currently occupy 8.5% of their presumed historical range. One population survives in Utah, occurring in San Juan County. The Gunnison Sage-grouse Rangewide Conservation Plan and the San Juan County Gunnison Sage-grouse Conservation Plan recommended management strategies to address identified conservation threats to the Utah population. I addressed three conservation strategies identified in the plans: 1) creation and enhancement of brood-rearing areas; 2) assessment of habitat conditions within the Gunnison Sage-grouse Conservation Area; and 3) prevention or reduction of perching events by avian predators on distribution line power poles. From 2007-2009, I addressed the conservation strategy of creating mesic brood-rearing areas in Conservation Reserve Program fields and native sagebrush areas by evaluating the role of irrigation and dormant season cattle grazing on habitat. Vegetation and arthropod diversity in irrigated versus non-irrigated plots did not differ (p>0.01). Conservation Reserve Program plots exhibited greater arthropod abundance and cover of perennial grass than the native sagebrush plots, but lower diversity of perennial grasses and abundance and diversity of forbs (p<0.01). The second conservation strategy I addressed was the completion of an assessment of habitat conditions within the Gunnison Sage-grouse Conservation Area. I measured vegetation conditions within habitat occupied and unoccupied by Gunnison sage-grouse. Cover and height of grasses exceeded guidelines for occupied and unoccupied habitats. Forb cover was below recommended guidelines in occupied habitat. Sagebrush cover was below guidelines for winter habitat. Habitat restoration efforts should focus on retaining existing sagebrush cover and establishment of sagebrush, forb, and grass cover within Conservation Reserve Program fields. The third conservation strategy I evaluated was the retrofitting of distribution line power poles with perch deterrents to discourage avian predators from perching. I evaluated the efficacy of five perch deterrents. The perch deterrents did not mitigate potential avian predators from perching. A deterrent designed for insulators, in combination with physical deterrents we tested, has potential to prevent perching. These studies provided a sound first step that can be built upon by the Monticello/Dove Creek Local Working Group to improve habitat conditions, reduce the threat of avian predation, and plan future conservation activities within the Conservation Area.

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