975 resultados para Birds in art.


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Previous studies suggest that many species of insectivorous bats are nocturnal, despite the relatively low availability of their insect prey at night, because of the risk of predation by diurnal predatory birds. We hypothesised that if this was the case bats living above the arctic circle would alter their feeding behaviour during midsummer because there would no longer be any benefit to restricting their activity to the period when their prey are least abundant. Alternatively, if bats were more influenced by competition from aerial insectivorous birds they would continue to feed at ‘night’ to avoid such competition. In northern Norway (69° N), during continuous midsummer daylight, insectivorous sand martins (Riparia riparia) concentrated their aerial feeding activity when aerial insects were most abundant. The birds stopped feeding between 23:00 and 07:00 when aerial insects were least abundant. In contrast, northern bats (Eptesicus nilssonii), fed mostly between 22:00 and 02:00, coinciding with the lowest aerial insect availability, and with the period when light levels were lowest (ca 1000 lux). Bat activity patterns were closest to those predicted by the avian competition hypothesis. The low densities of both sand martins and Northern bats in the study area, however, were less consistent with this hypothesis. Possibly populations of both species were higher historically and the observed patterns reflected historical competition. Bat activity was most closely correlated to ambient light levels. This raised two alternative explanations that we could not eliminate. Perhaps there was differential predation risk, between the brightest and darkest parts of the day, because the visual capacities of falcons are strongly dependent on luminance. Alternatively the bats may have been entrained to emerge at given light levels by their behaviour at other times of year.

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1. Identifying landscape patterns that allow native fauna to coexist with human land use is a global challenge. Riparian vegetation often persists in anthropogenic environments as strips of natural or semi-natural vegetation that provide habitat for many terrestrial species. Its relative contribution to landscape-scale conservation is likely to change as environments become increasingly modified. We used a ‘whole of landscape’ approach to test the hypothesis that riparian vegetation offers disproportionate benefits, relative to non-riparian vegetation, for the conservation of woodland birds in highly modified agricultural landscapes. 2. We selected 24 landscapes, each 100 km2, along a gradient of landscape change represented by decreasing cover of native vegetation (from 60% to <2%), in an agricultural region in SE Australia. Bird species were systematically surveyed at three riparian and seven non-riparian sites in wooded vegetation in each landscape. 3. Riparian sites supported a greater richness of woodland-dependent species, a group of conservation concern, than did non-riparian sites. The composition of assemblages also differed between site types. 4. At the landscape scale, the pooled richness of bird assemblages at riparian and non-riparian sites, respectively, decreased with overall loss of tree cover despite constant sampling effort. Within landscapes, the β-diversity of woodland species among non-riparian sites increased (composition became less similar) as landscape tree cover declined. In contrast, riparian assemblages were relatively stable with no change in β-diversity. Importantly, as landscape tree cover declined, the proportion of woodland species uniquely present at riparian sites increased and made a greater contribution to overall landscape diversity. 5. Synthesis and applications. Landscape-scale richness of woodland species declines as landscape tree cover is lost. In highly depleted landscapes, riparian vegetation retains a relatively rich, stable assemblage compared with that in heterogeneous remnants of non-riparian vegetation and consequently contributes disproportionately to landscape-scale diversity. These observations, together with the diverse benefits of riparian vegetation for aquatic ecosystems, mean that protection and restoration of riparian vegetation is a high priority in anthropogenic environments. Importantly, such actions are directly amenable to individual land managers, and the benefits will accumulate to enhance the persistence and conservation of species at landscape and regional scales.

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A longstanding, successful and frequently controversial career spanning more than four decades establishes David Bowie as charged with individual agency. The notion of ‘agency’ here refers particularly to the ‘ability of people, individually and collectively to influence their own lives and the society in which they live’ (Germov and Poole, 2007: 7). That Bowie has influenced many lives is undeniable to his fans. He has long demonstrated an avid curiosity for the enduring patterns of social life which is reflected in his art. Bowie’s opus contains the elements of ideological narratives around sexual (mis)adventure, expressivity, and; resistance to ‘normative’ behaviour. He requisitions his audiences, through frequently indirect lyrics and images, to critically question sanity, identity and essentially what it means to be ‘us’ and why we are here. Here, in this context, ‘dancing with madness’ assumes an intimate relationship, even if brief, where ideas and emotions come passionately together for the purpose of creative expression much like the intertwining and energetic performance of the partner dance Tango. As such, ‘dancing’ is argued here to be an appropriate descriptor for how Bowie has engaged with creative cultural forms but not meant to be self-conscious nor indicate superficiality or ignorance. The idea of madness for its part is a theme in many of his compositions, for example the original album cover for The Man Who Sold the World (1971)  depicts an asylum and includes the song ‘All The Madmen’ and Aladdin Sane (1973)—a lad insane--are but two examples. This paper argues that Bowie’s frequently astute contemplations, manifest through his art over a period now spanning more than forty years, continues to draw fans of like mind to his work with the result that he has a legitimate claim to influence and affect.

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Bird feeding in residential gardens is an increasingly popular human-wildlife interaction. In Australia, the practice is discouraged by most government and nongovernment wildlife conservation agencies, although advice varies and the most common recommendation is to provide water and habitat for birds rather than supplementary food. This study compares bird abundance and diversity when residents in a Melbourne municipality provide water for birds versus food. Bird abundance was greater when food was provided compared with water, but avian assemblages did not differ.

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Faculty from Rhode Island School of Design representing Interior Architecture, Industrial Design, and Textiles detail their thoughtful interactions with materials.

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Designers respond to issues and synthesize ideas from throughout the day as voices from the field who directly encounter the need for recently graduated students to possess the ability to investigate and interrogate materials.