Thesis (M.Sc.)--Acadia University, 1999. / Includes bibliographical references (leaves 68-71). Also available on the Internet via the World Wide Web.

A surge of recent work elucidating a role for learning and memory in avian nest-building behaviour has challenged the long-standing assumption that nest building develops under genetic control. Whereas that work has been addressed at describing the cognitive mechanisms underpinning nest-building behaviour, almost nothing is known about either the neurobiological processes controlling nest building or the selection pressures responsible for the diversity in avian nest-building behaviour. Here, I sought to identify both the neural substrates involved in nest-building behaviour and some of those selection pressures. First, I used expression of the immediate early gene product Fos, an indirect marker of neuronal activity, to identify brain regions activated during nest-building behaviour in the brains of nest-building and control zebra finches (Taeniogypia guttata). I found that neural circuits involved in motor control, social behaviour, and reward were activated during nest building. Furthermore, I found that subpopulations of neurons that signal using the nonapeptides vasotocin and mesotocin and the neurotransmitter dopamine located within some of these neural circuits were also activated during nest building, suggesting these cell-signalling molecules may be involved in controlling nest-building behaviour. Next, I found that variation in the amount of folding in the cerebellum, a brain structure thought to be involved in manipulative skills, increased with increasing nest structural complexity, suggesting that the cerebellum is also involved in nest building. Finally, using evolutionary statistical models, I found support for the hypothesis that nest-site competition off-ground and increased predation pressure on the ground in Old World babblers (Timaliidae) led to the co-evolution of building domed nests on the ground. Here, then, I provide the first evidence of potential neural substrates controlling and selection pressures contributing to variation in nest-building behaviour.

Abstract Globally, populations of several wader species are in decline. However, for most populations, information on abundance, its changes and the causes of declines is insufficient for designing successful management strategies to recover threatened populations. In this thesis I studied the status and population trends, nesting success, genetic structure and viability of a small, declining and threatened Temminck's stint population in the Bothnian Bay in the northern Baltic Sea. Historical population data, recent population counts in the early 1990s and in 1999–2002 and the demographic data showed that the decline is continuing, paralleled by declines in nesting success, recruitment and adult survival. Decline in nesting success was caused by a coincident increase in nest predation. Depredation was the main cause of nest losses. The common gull (Larus canus) and the ruddy turnstone (Arenaria interpres) were found to be the most important nest predators. I tested if an increase in nest concealment and consequent decrease in visibility lowers the efficiency of the early-departure antipredator behaviour of the species. An expected positive correlation emerged between visibility and flushing distance in the presence of alarm-giving birds, but not without them. This indicates that Temminck's stint exploits signals from other birds as early warning of an approaching predator. More nests were lost to predation on narrow than on wide shores. The nest predation rate was not related to habitat (natural vs. man-made) nor to differences in microhabitat characteristics associated with concealment. Overall variability of the mitochondrial control region was low in the one northeast Siberian and the three Fennoscandian populations studied. The occurrence of two maternal lineages in all Fennoscandian populations points to mixing of two previously isolated populations. The overall microsatellite genetic structuring (6 loci) in Fennoscandia was low. The pairwise comparison revealed a low but significant degree of differentiation between the Bothnian Bay and the two other Fennoscandian populations. However, no clear indication of genetic effects of small population size in the Bothnian Bay was detected. Matrix and Pradel-λ projection models, based on a ten year (1994–2003) capture-recapture data set, predicted a steep future decrease and a high risk of extinction within 50 years. Without immigration the decline would lead to extinction within 20 years. Population growth was the most sensitive to changes in adult survival, the rate of which declined during the study. Factors affecting adult survival most likely operate primarily during the non-breeding season in locations specific to the study population that are virtually unknown. Management efforts in the Bothnian Bay should, in addition to improving hatching success, first of all guarantee availability of wide, low-sward coastal breeding habitats for potential immigrants and recruits.

Eastern wild turkeys (Meleagris gallapavo silvestris) were extirpated from most of the Mississippi Alluvial Valley (MAV) by 1980 by overharvest and habitat loss. Federal programs have restored areas of the MAV to hardwood forest, potentially warranting restoring wild turkeys to the MAV. As part of a pilot restoration study, I gathered data on resource use and nest sites from July 2010–August 2011. I observed intraspecific niche specialization and spatial niche separation between genders. Spatiotemporal variation in resource availability and intraspecific competition appear to be factors influencing intraspecific niche specialization. Mature hardwood forest was primary habitat selected by translocated wild turkeys. Hardwood regeneration areas were primary habitat selected by hens for nesting. Visual obstruction from 0.0 m–0.5 m was important in selecting fine-scale nest sites. Hardwood regeneration areas have dual value for restoring wild turkeys to the MAV: future mature hardwood areas; and potential nest sites.

Northern Goshawk breeding habitat was conceptualized and analyzed as a system composed of different sized components organized within a hierarchy. The organization of the hierarchy was asymmetric with smaller components nested within and subordinate to larger components. Components considered in the breeding habitat hierarchy of goshawks were nest tree, nest site, nest territory, foraging area, and landscape. Choice at any level within the hierarchy was contrasted with the next level in the hierarchy. Thus it was found that goshawks chose nest trees with a largerdbh (79.0 ± 4.4 cm) than the nest site average (43 ± 2.7 cm) (p=0.000036); the averagedbh of the nest site (43.2± 3.1 cm) was significantly larger than the territory (33.2± 1.9cm) (p=0.018). The nest territory when contrasted with random unoccupied locations in the landscape demonstrated a composition of a central site of trees with largedbh and fewer stems when compared with the surrounding forest. I hypothesize that this pattern reduces thepredation risk at the nest site. I investigated the nest site relative to the assumed foraging area (radius of 3000m; approximately 3000ha). Goshawks selected nest sites which were significantly further from young clear cuts (>10 ha). The average distance from a nest site to a recentclearcut greater than 10 ha was 1,350 m of the nest while for unoccupied sites the average distance was 770 m (p = 0.011). Finally, at the landscape level, areas of approximately 10,000 ha, goshawks on Vancouver Island were more abundant, had more nest sites, and had higher productivity per active nest in old growth forests (>120 years) than in either second growth (majority less than 80 years) or fragmented landscapes. The majority of goshawk prey, as determined though pellet analysis was red squirrel (69%). Red squirrels were equally abundant in second growth and old growth yet less abundant in fragmented landscapes. Despite similar abundance of their main prey item goshawks were not as abundant in second growth forests as in old growth forests. I conclude that the structure of second growth and fragmented landscape reduces the availability of key prey species and therefor the suitability of these landscape fpr goshawks is lower. / Graduate

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Thesis (MSc.(Clinical Psychology))University of Limpopo, 2010. / The aim of the study is to analyse the film One flew over the cuckoo’s nest, from a clinical psychology perspective in order to evaluate the possible use of the film and significant concepts depicted therein in a training context. The objectives of the study are to describe the interactional dynamics of the psychiatric system as depicted in the film, to identify and describe the impact of the systems and/or subsystems on the psychotherapeutic growth of “patients” and to provide suggestions for the training of psychotherapists on the basis of the film and the present research. A qualitative, descriptive research design was used to achieve these aims. This allowed for systematic clinical descriptions by four clinical psychologists to be obtained. The study involved an exploration of relevant literature as well as an indepth study of a specific therapeutic group in interaction as depicted in the film. The film was shown to four clinical psychologists. Their findings were analysed, and common themes in their analyses identified. The researcher came to certain conclusions on the basis of the above-mentioned analyses. The findings of this study seem to indicate that the interactional style of the psychiatric staff, as portrayed in the film, contributed to the deterioration of the psychological well-being of the “patients”, thus inhibiting their psychological growth and promoting psychopathology. In spite of the findings, the researcher wishes to recommend the utilisation of this film as a training medium, on condition that a paradigm shift is made away from the traditional medical/psychiatric approach to a ii systems-based epistemology. This could result in viewing the psychiatric system as a hierarchy of interrelated subsystems-in-interaction, and open up possibilities for a redefinition of the various roles of those involved within the larger system. Further research in this direction is strongly indicated and recommended.

Surface mining and subsequent reclamation often results in the establishment of large areas of grassland that can benefit wildlife. Grasslands have declined substantially over the last 150 years, resulting in declines of many grassland birds. The dickcissel (Spiza americana), a neotropical migrant, is one such bird whose numbers have declined in the last 30 years due to habitat loss, increased nest predation and parasitism, and over harvest (lethally controlled as an agricultural pest on its wintering range in Central and South America). Reclaimed surface-mined lands have been documented to provide important breeding habitat for dickcissels in the United States, emphasizing the importance of reclamation efforts. Objectives were to understand specific aspects of dickcissel nesting ecology (i.e., nest-site selection, nest success, and nest parasitism, and identification of nest predators) on 2 spatial scales on TXU Energy’s Big Brown Mine, near Fairfield, Texas, and to subsequently provide TXU Energy with recommendations to improve reclaimed areas as breeding habitat for dickcissels. I examined the influence of nest-site vegetation characteristics and the effects of field-level spatial factors on dickcissel nesting ecology on 2 sites reclaimed as wildlife habitat. Additionally, I developed a novel technique to identify predators at active nests during the 2003 field season. During 2002–2003, 119 nests were monitored. On smaller spatial scales, dickcissels were likely to select nest-sites with low vegetation, high densities of bunchgrasses and tall forbs, and areas with higher clover content. Probability of nest success increased with nest heights and vegetation heights above the nest, characteristics associated with woody nesting substrates. Woody nesting substrates were selected and bunchgrasses were avoided. Oak (Quercus spp.) saplings remained an important nesting substrate throughout the breeding season. On a larger scale, nest-site selection was likely to occur farther from wooded riparian areas and closer to recently-reclaimed areas. Nest parasitism was likely to occur near roads and wooded riparian areas. Results suggest reclaimed areas could be improved by planting more bunchgrasses, tall forbs (e.g., curly-cup gumweed [Grindelia squarrosa] and sunflower [Helianthus spp.]), clover (Trifolium spp.), and oaks (a preferred nesting substrate associated with higher survival rates). Larger-scale analysis suggests that larger tracts of wildlife areas should be created with wooded riparian areas comprising a minimal portion of a field’s edge.

The prairies of North America have undergone substantial changes since European settlement in the 1800's, with some estimates suggesting that 96% of the tallgrass prairie has been converted. Multiple factors contributed to reduction in prairie, including: grazing, row-crop farming, depressed fire regimes, and exotic grass species introduction. In Texas, 35% of the historic grassland ecosystems have been either altered or converted. Introduced in the 1940's, exotic grass species such as Bermuda grass (Cynodon sp) have displaced native grass species throughout Texas. Introduced grass species can alter the existing plant communities degrading habitat for birds and other animals. Grassland birds are declining faster than any other bird group within North America; due in part to a reduction in suitable breeding habitat. I addressed this issue by comparing nesting success of grassland birds between exotic grass sites and restored native grass sites in the blackland prairie region of east-central Texas during 2007-2008 breeding seasons. I conducted point counts and nest searching from March - July. Point count data indicate no difference in species richness between sites. Dickcissel (Spiza americana) nests represented 89% of the nests found (n = 104). Dickcissel abundance was 44% higher in restored sites and 76% of nests were located in restored sites. Daily survival (DSR) for dickcissels in restored sites was 0.895 (SE = 0.013) and for exotic sites was 0.930 (SE = 0.017). I used an independent samples t-test to compare mean nest height, which was 56% higher in restored sites than exotic sites (n = 83, x bar = 38.0 cm plus/minus 1.90; x bar = 15.2 cm plus/minus 2.19, df = 81, t = -6.31, P = 0.001), and mean nest substrate height which was 58% higher in restored sites than in exotic sites (n = 83, x bar = 118.8 cm plus/minus 6.50; x bar = 46.5 cm plus/minus 4.77, df = 81, t = -6.08, P = 0.001). Although dickcissel abundance was greater in restored sites than exotic sites, their observed nesting success and DSR was lower in restored sites. This is indicative of an ecological trap, which occurs when an organism is attracted to a habitat that negatively impacts the organism. Some research suggests that restored fields in other states are acting as traps for dickcissels, and according to my results restored sites I sampled may also be acting as ecological traps for dickcissels in Texas.