949 resultados para Cleveland Bay horse.
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Mode of access: Internet.
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1. Many species of delphinids co-occur in space and time. However, little is known of their ecological interactions and the underlying mechanisms that mediate their coexistence. 2. Snubfin Orcaella heinsohni, and Indo-Pacific humpback dolphins Sousa chinensis, live in sympatry throughout most of their range in Australian waters. I conducted boat-based surveys in Cleveland Bay, north-east Queensland, to collect data on the space and habitat use of both species. Using Geographic Information Systems, kernel methods and Euclidean distances I investigated interspecific differences in their space use patterns, behaviour and habitat preferences. 3. Core areas of use (50% kernel range) for both species were located close to river mouths and modified habitat such as dredged channels and breakwaters close to the Port of Townsville. Foraging and travelling activities were the dominant behavioural activities of snubfin and humpback dolphins within and outside their core areas. 4. Their representative ranges (95% kernel range) overlapped considerably, with shared areas showing strong concordance in the space use by both species. Nevertheless, snubfin dolphins preferred slightly shallower (1-2 m) waters than humpback dolphins (2-5 m). Additionally, shallow areas with seagrass ranked high in the habitat preferences of snubfin dolphins, whereas humpback dolphins favoured dredged channels. 5. Slight differences in habitat preferences appear to be one of the principal factors maintaining the coexistence of snubfin and humpback dolphins. I suggest diet partitioning and interspecific aggression as the major forces determining habitat selection in these sympatric species.
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A regime shift in the North Sea circa 1988 linked to changes in the North Sea horse mackerel fishery
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After 1987, Phytoplankton Colour (a visual estimate of chlorophyll) measured on samples taken by the continuous plankton recorder (CPR) in the North Sea increased substantially, both in level and seasonal extent, compared to earlier years since 1946. Many species of phytoplankton and zooplankton showed marked changes in abundance at about the same time. These events coincided with a large increase in catches of the western stock of the horse mackerel (Trachurus trachurus L.) in the northern North Sea reflecting a northerly expansion of the stock along the shelf edge from the Bay of Biscay to the North Sea after 1987. Using a 3D hydrodynamic model, with input from measured wind parameters, monthly transport of oceanic water into the North Sea has been calculated for the period 1976–1994, integrated for a section from Orkney to Shetland to Norway. A substantial increase in oceanic inflow occurred in the winter months, December to March, from 1988. Higher sea surface temperatures were also measured after 1987 especially in spring and summer months. These biological and physical events may be a response to observed changes in pressure distribution over the North Atlantic. From 1988 onwards, the North Atlantic Oscillation (NAO) index, the pressure difference between Iceland and the Azores, increased to the highest positive level observed in this century. Positive NAO anomalies are associated with stronger and more southerly tracks of the westerly winds and higher temperatures in western Europe. These changing wind distributions may have led to an increase in the northerly advection of water along the western edge of the European shelf and may have assisted the migration of the horse mackerel. This study is possibly a unique demonstration of a correlation between three different trophic levels of a marine ecosystem and hydrographic and atmospheric events at decadal and regional scales. The results emphasise the importance of maintaining into the future long term programmes such as the CPR.
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In April 2008 a Franches-Montagnes colt was born with an unusual coat colour phenotype which had never been observed in that population before. The foal showed extended white markings on body and legs, a white head and blue eyes. As both parents have an unremarkable bay coat colour phenotype, a de novo mutation was expected in the offspring and a candidate gene approach revealed a spontaneous mutation in the microphthalmia associated transcription factor gene (MITF). A detailed clinical examination in 2010 indicated an impaired hearing capacity. As in the American Paint Horse large white facial markings in combination with blue eyes are associated with deafness, the hearing capacity of the stallion was closer examined performing brainstem auditory-evoked responses (BAER). The BAER confirmed bilateral deafness in the Franches-Montagnes colt. It is assumed that the deafness is caused by a melanocyte deficiency caused by the MITF gene mutation. Unfortunately, due to castration of the horse, the causal association between the mutation in the MITF gene and clinical findings cannot be confirmed by experimental matings.
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Seagrass meadows are important marine carbon sinks, yet they are threatened and declining worldwide. Seagrass management and conservation requires adequate understanding of the physical and biological factors determining carbon content in seagrass sediments. Here, we identified key factors that influence carbon content in seagrass meadows across several environmental gradients in Moreton Bay, SE Queensland. Sampling was conducted in two regions: (1) Canopy Complexity, 98 sites on the Eastern Banks, where seagrass canopy structure and species composition varied while turbidity was consistently low; and (2) Turbidity Gradient, 11 locations across the entire bay, where turbidity varied among sampling locations. Sediment organic carbon content and seagrass structural complexity (shoot density, leaf area, and species specific characteristics) were measured from shallow sediment and seagrass biomass cores at each location, respectively. Environmental data were obtained from empirical measurements (water quality) and models (wave height). The key factors influencing carbon content in seagrass sediments were seagrass structural complexity, turbidity, water depth, and wave height. In the Canopy Complexity region, carbon content was higher for shallower sites and those with higher seagrass structural complexity. When turbidity varied along the Turbidity Gradient, carbon content was higher at sites with high turbidity. In both regions carbon content was consistently higher in sheltered areas with lower wave height. Seagrass canopy structure, water depth, turbidity, and hydrodynamic setting of seagrass meadows should therefore be considered in conservation and management strategies that aim to maximize sediment carbon content.
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This photograph shows Put-in-Bay Harbor with Gibraltar Island across the bay in the background. This image was made from a stereoview card created by A. C. Platt in the 1880s. South Bass Island was a popular destination in the 1880s for residents of Toledo, Cleveland, and Detroit.
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Bayesian Belief Networks (BBNs) are emerging as valuable tools for investigating complex ecological problems. In a BBN, the important variables in a problem are identified and causal relationships are represented graphically. Underpinning this is the probabilistic framework in which variables can take on a finite range of mutually exclusive states. Associated with each variable is a conditional probability table (CPT), showing the probability of a variable attaining each of its possible states conditioned on all possible combinations of it parents. Whilst the variables (nodes) are connected, the CPT attached to each node can be quantified independently. This allows each variable to be populated with the best data available, including expert opinion, simulation results or observed data. It also allows the information to be easily updated as better data become available ----- ----- This paper reports on the process of developing a BBN to better understand the initial rapid growth phase (initiation) of a marine cyanobacterium, Lyngbya majuscula, in Moreton Bay, Queensland. Anecdotal evidence suggests that Lyngbya blooms in this region have increased in severity and extent over the past decade. Lyngbya has been associated with acute dermatitis and a range of other health problems in humans. Blooms have been linked to ecosystem degradation and have also damaged commercial and recreational fisheries. However, the causes of blooms are as yet poorly understood.
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Research Background - Young people with negative experiences of mainstream education often display low levels of traditional academic achievement. These young people tend to display considerable cultural and social resources developed through their repeated experiences of adversity. Education research has a duty to provide these young people with opportunities to showcase, assess and translate their social and cultural resources into symbolic forms of capital. This creative work addresses the following research question. How can educators develop disengaged teenager's social and cultural capital through live music performances? Research Contribution - These live music performances afford the young participants opportunities to display their artistic, technical, social and cultural resources through a popular cultural format. In doing so they require education institutions to provide venues that demonstrate the skills these young people acquire through flexible learning environments. The new knowledge derived from this research focuses on the academic and self confidence benefits for disengaged young people using festival performances as authentic learning activities. Research Significance - This research is significant because it aims to maximise the number of tangible outcomes related to a school-based arts project. The young participants gained technical, artistic, social and commercial skills during this project. This performance led to more recording and opportunities to perform at other youth festivals in SE QLD. Individual performances were distributed and downloaded via creative commons licences at the Australian Creative Resource Archive. It also contributed to their certified qualifications and acted as pilot research data for two competitively funded ARC grants (DP0209421 & LP0883643)
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One of the most wide-ranging and sophisticated critiques of creative industries policy argues that it is a kind of Trojan horse, secreting the intellectual heritage of the information society and its technocratic baggage into the realm of cultural practice, suborning the latter's proper claims on the public purse and self-understanding, and aligning it with inappropriate bedfellows such as business services, telecommunications and calls for increases in generic creativity. Reviewing the broad adoption of the concept in policy discourse around the world, this paper suggests that rather than a Trojan horse, it might be better thought of as a Rorschach blot, being invested in for varying reasons and with varying emphases and outcomes. Based on spatial analysis, then, the critique may need modification. Temporally as well, the critique may have been overtaken by later developments taking policy emphases 'beyond' the creative industries.
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Jack's Bay (the architecturalisation of memory) is a key work of the author's exhibition Lightsite, which toured Western Australian galleries from February 2006 to November 2007. It is a five-minute-long exposure photographic image captured inside a purpose-built, room-sized pinhole camera which is demountable and does not have a floor. The work depicts octogenarian Jack Morris, who for forty years held the professional salmon fishing license in the hamlet of Bremer Bay, on the SE coast of Western Australia. The pinhole camera-room is sited within sand dunes new Jack's now demolished beachside camp. Three generations of Jack's descendents stand outside the room - from his daughter to his great grand children. The light from this exterior landscape is 'projected' inside the camera-room and illuminates the interior scene which includes that part of the sand dune upon which the floorless room is erected, along with Jack who is sitting inside. The image evokes the temporality of light. Here, light itself is portrayed as the primary medium through which we both perceive and describe landscape. In this way it is through the agency of light that we construct our connectivity to landscape.
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Jack's Bay expands understandings of the role of photographic media in the representation of landscapes. It does so by combining architectural construction with B&W photographic processing techniques. A purpose-built room-sized camera obscura is first constructed over a portion of the landscape to be recorded. Photosensitive paper is applied to the interior wall surfaces and is exposed to the inverted light entering a small aperture. These photographs are subsequently developed within the camera itself and consequently 'suffer' embellishments and aberrations from the makeshift darkroom conditions. In this way the specificity of both the landscape and the event of its recording are registered in the final image. Many images were destroyed in the process. The idea of the work is to help the viewer reflect on the role media plays in our understanding of landscape and to thus question the means by which they themselves record and interpret landscape representations.