No description available.

The vulnerability and movement behaviour of slow moving slides are investigated. The study focuses on slides moving at rates ranging from a few millimetres a year like extremely slow slides, to 13 meters per month, the upper velocity range of slow slides. An extensive review of the effect of pore pressure changes on movement reactivation of shallow and moderately thick slides is presented. The time dependent behaviour of fine geotechnical materials is also reviewed. Although the literature has reported many cases where the accumulation of slow movements led to a complete collapse of buildings, failure of embankment slopes carrying highways or railways and serviceability problems for dams and bridges, little attention has been paid to the vulnerability to slow moving slides. Hence, this thesis aims to provide more insight into the actual damage to facilities founded on slow moving slides. More than fifty cases of extremely slow, very slow and slow slides adversely affecting urban communities, highways, railways, bridges, dams and linear infrastructure are reviewed. The survey enables the development of new damage-extent scales that use the slide velocity to help assess the degree of damage to a facility founded on a landslide-prone area. Vulnerability is an important component of the specific risk. The other component is the hazard or the probability of occurrence of a certain damaging phenomenon like landslides. Defining the causal factors of the landslide movements and their contributions to the total movement is an important step towards the evaluation of the hazard. Hence, the geomechanical behaviour of two typical deep-seated and moderately thick slides, the Little Chief Slide and the Little Smoky Slide, respectively, are investigated. The objective is to determine all the triggers and causal factors of movement and to quantify their contribution to the total movement. The study involves groundwater flow modeling of one of the two slides, an extensive field monitoring of pore pressures and displacements and an investigation of the creep behaviour both in the field and in the laboratory. The outcome of the study shows that the total movement of each of the two slides can be separated into creep and seasonal movements. The contribution of each component is quantitatively defined. The quantification of the different causal factors aids in choosing the proper mitigation option in addition to predicting the future movement rates after the chosen remedial measures have been installed. / Geotechnical Engineering

Lesser prairie chicken (Tympanuchus pallidicinctus; LPC) numbers have declined considerably in Texas since the early 1900s. As with other prairie chicken species, reasons for declining ranges and numbers have been attributed primarily to degradation and fragmentation of habitats. Until my study, no telemetry-based research on LPC has been conducted in the Rolling Plains of the Texas Panhandle. I radio-tagged and monitored LPCs in 2001 (spring??winter) and 2002 (spring) at a stable population in a native rangeland landscape (Study Area I) and in a declining population in a fragmented rangeland and agricultural landscape (Study Area II). No significant (P < 0.05) differences in survival were detected for combined study areas between years, or between study areas within years. Ranges and movements, as independent criteria by season, sex, and age classes combined were similar (P > 0.05) for both study areas. Lesser prairie chickens predominately occupied native rangeland cover types (>85%) compared to non-native rangelands at both study areas. Total invertebrate dry mass for all orders differed between native rangeland and Conservation Reserve Program (CRP) sites at Study Area II. Over 32 times more dry mass of invertebrates was collected at the native rangeland site than were collected at the CRP site. Herbaceous cover differed significantly for grasses (P < 0.01), forbs (P < 0.01), and bare ground (P < 0.01), but not for litter (P = 0.43) or woody cover (P = 0.63) between study areas. The similar range sizes, movement distances, and cover use observed for both study areas may provide insight into minimum area requirements for LPCs within the Rolling Plains in the Texas Panhandle.

The majority of interior cutthroat trout (Oncorhynchus clarki) subspecies have been extirpated from large rivers by anthropogenic activities that have fragmented habitats and introduced non-native competitors. Selective pressures against migratory behaviors and mainstream river occupation and conservation schemes that isolate genetically pure populations above barriers have restricted gene flow and prevented the expression of fluvial life history traits in many populations. Existing knowledge about the movements and home range requirements of fluvial cutthroat trout is therefore limited. We implanted a total of 55 Bonneville cutthroat trout (BCT) in the Thomas Fork River, Idaho, with radio transmitters and located them weekly or bimonthly from October to April of both 1999/2000 and 2000/2001. Half of these fish were located above a seasonal diversion barrier and half were located below. We found fish to be more mobile than previously reported. Individuals located above the diversion barrier in 2000/2001 occupied significantly larger home ranges (median 3,675 m, range 2,500-8,900 m) and moved more frequently (mean 0.89 movements/contact, range 0.57-1.0) than other fish. Fish occupied habitats in the lower Thomas Fork and Bear River during the winter that were marginal or uninhabitable during other seasons. During the spring of both years we located fish in both upstream and neighboring tributaries up to 84 km away from our study site. Our results document the existence of a fluvial component of BCT in the Bear River and its tributaries and suggest that successful efforts at conservation of these fish will focus on mainstream habitats and the maintenance of seasonal migration corridors.

The Great Plains variety of the sharp-tailed grouse Pediocetes phasianellus jamesi Lincoln was the predominant upland game bird during the exploratory and early settlement period in North Dakota (Coues 1874 and 1878 . Larson 1928, and Williams 1926) . Since then its status has diminished as the prairie grassland gradually was converted to intensively used pastures and cropland. Although the sharptail is still abundant enough in its remaining habitat to provide for liberal annual harvests , further demand on these lands by a growing human population will make it necessary to apply game management measures other than hunting regulations if the sharptail is to be retained as an important game bird in the state.

Peregrines Falco peregrinus and Gyrfalcons F. rusticolus were studied in Low and High Arctic Greenland, comparing populations within and between areas. Analyses of weather data from northwest Greenland (1979–2005) revealed a general warming trend, resulting in a lengthened breeding window for many bird species. Both falcon species depend on cliffs for nesting, and take a similar range of bird species as prey. However, Gyrfalcons lay six weeks earlier than Peregrines in Kangerlussuaq and one month earlier than Peregrines in Thule, and occupy more sheltered nest-sites. Being larger than Peregrines, Gyrfalcons also take some larger prey species. In addition, both species move to lower latitudes for the winter, but while most Gyrfalcons migrate relatively short distances, Peregrines are complete long-distance migrants to Central and South America. One Peregrine, satellite-tracked from its breeding site at 76.5° N, travelled ~12,500 km and >100° in latitude, one of the longest migrations ever documented for a raptor. Around Thule in northwest Greenland (at 76.5° N), scientists had historically documented no breeding Peregrines, but six occupied sites were discovered during this study, comprising what is probably the most northern nesting population in the world. Over the same period, breeding Gyrfalcons have apparently disappeared from southern Greenland, and may have declined in central-west Greenland (67° N). The ultimate cause of this retraction may be climate warming, but the proximate cause is probably competition from an increasing Peregrine population. Gyrfalcons tagged with satellite-received transmitters showed characteristics associated with both obligate and facultative migration. Their winter ranges varied greatly in size, with the largest, ~172,000 km2, being the biggest ever documented for a raptor. Many individuals made long movements within a winter, and some spent up to a month at sea. They may have rested on ice and fed upon seabirds. Carbon dating of stratified faecal accumulation from Gyrfalcon nests in central-west and northwest Greenland showed use of sites for up to ~2,500 and ~650 years, respectively. The age of nest sites correlated significantly with the current distance to the Greenland Ice Sheet, and probably reflects colonization patterns following glacial retreat. In central-west Greenland the ratio of Peregrine to Gyrfalcon pairs changed from 1:1 in the early 1970s to nearly 14:1 in 2005. Over this period, competition for nest sites and prey is likely to have intensified. The crucial prey for Gyrfalcons when they start nesting in early spring are resident ptarmigan, whose numbers are probably depleted by Peregrines during the months they are present. If recent trends in climate change continue, Peregrines may continue to increase in Greenland, and spread north into areas previously occupied only by Gyrfalcons. At the same time, Gyrfalcons may retreat north from many currently-occupied areas.