1000 resultados para Asian birds


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With respect to its avian migrants, Australo-Papua is a largely self-contained region. Only some 30 species of shorebird and 10 species of land bird migrate from Asia to Australo-Papua to winter. Possible factors precluding migration of Asian birds include long over-water distances and lack of suitable habitats in Australia or New Guinea. Whether evolved within the region or descended from Asian relatives, Australasian species all confine their migratory movements east of Wallace's Line. The most likely factors restricting migration to the region are climate and habitat. The open forests and arid habitats of Australasia are absent from south-east Asia, so there is little, if any, selection promoting extra-regional migration. The arid or semi-arid but otherwise mild climates of much of Australia favour partial migration and widely varying movement patterns and pathways, although with an underlying north to south component. Movements also occur between mainland Australia and New Guinea and Tasmania. The restriction of migration within Australo-Papua and the high variability of migratory pathways have important implications for the ecology and evolution of the Australasian avifauna.

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Veterinary use of the nonsteroidal anti-inflammatory (NSAID) drug diclofenac in South Asia has resulted in the collapse of populations of three vulture species of the genus Gyps to the most severe category of global extinction risk. Vultures are exposed to diclofenac when scavenging on livestock treated with the drug shortly before death. Diclofenac causes kidney damage, increased serum uric acid concentrations, visceral gout, and death. Concern about this issue led the Indian Government to announce its intention to ban the veterinary use of diclofenac by September 2005. Implementation of a ban is still in progress late in 2005, and to facilitate this we sought potential alternative NSAIDs by obtaining information from captive bird collections worldwide. We found that the NSAID meloxicam had been administered to 35 captive Gyps vultures with no apparent ill effects. We then undertook a phased programme of safety testing of meloxicam on the African white-backed vulture Gyps africanus, which we had previously established to be as susceptible to diclofenac poisoning as the endangered Asian Gyps vultures. We estimated the likely maximum level of exposure (MLE) of wild vultures and dosed birds by gavage (oral administration) with increasing quantities of the drug until the likely MLE was exceeded in a sample of 40 G. africanus. Subsequently, six G. africanus were fed tissues from cattle which had been treated with a higher than standard veterinary course of meloxicam prior to death. In the final phase, ten Asian vultures of two of the endangered species (Gyps bengalensis, Gyps indicus) were dosed with meloxicam by gavage; five of them at more than the likely MLE dosage. All meloxicam-treated birds survived all treatments, and none suffered any obvious clinical effects. Serum uric acid concentrations remained within the normal limits throughout, and were significantly lower than those from birds treated with diclofenac in other studies. We conclude that meloxicam is of low toxicity to Gyps vultures and that its use in place of diclofenac would reduce vulture mortality substantially in the Indian subcontinent. Meloxicam is already available for veterinary use in India.

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The cane toad (Bufo marinus), a large, toxic, American anuran, was introduced to Australia in 1935. Populations of many of Australia's reptiles (snakes, varanid lizards, crocodiles) and carnivorous mammals (dasyurid marsupials) have declined because these predators are killed by the toad's powerful toxins. In contrast to these well-studied species, little is known about the cane toads impacts on Australian birds. We reviewed published and unpublished data on behavioral interactions between Australian avian predators and cane toads and collated distributional and dietary information to identify avian taxa potentially at risk from cane toad invasion. Cane toads are sympatric with 172 frog-eating bird species in Australia, and an additional 8 bird species overlap with the predicted future range of the toad. Although many bird species thus are potentially at risk, behavioral observations suggest the risk level is generally low. Despite occasional reports of Australian birds being killed when they ingest cane toads, most birds either ignore toads or survive the predation event. The apparently higher tolerance of Australian birds to toad toxins, compared with Australian reptiles and marsupials, may reflect genetic exchange between Australian birds and Asian populations that encounter other bufonid species regularly and hence have evolved the capacity to recognize or tolerate this toxic prey. 

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In 2010, following successful trials with geolocators on Ruddy Turnstones in 2009, a total of 105 units, of four different models, were deployed at five locations on Ruddy Turnstones and Greater Sandplovers. Geolocator retrieval rates were 44% on Ruddy Turnstone and 27% on Greater Sandplover. Complete (59%) and partial (15%) technical failure rates on geolocators were high and were mostly the result of wear and saltwater corrosion. All 30 units from the Swiss Ornithological Institute failed. Only half of the Mk10 and Mk12 units from the British Antarctic Survey produced full migration histories. The northward migration of Ruddy Turnstones was on a narrow path with many birds completing an initial non-stop flight of 7,600 km to Taiwan. Later, most made a stopover in the Yellow Sea. Median migration duration was 39.5 days and average migration speed of the first major leg of the journey (assuming the birds followed the great circle route between stopovers) was 63.4 kph. Southward migration paths showed a much wider spread, ranging from Mongolia to the central Pacific. The latter involved the same bird that had been tracked along this route the previous year. It has now been logged on similar 27,000 km round trips in two successive years. The median duration of southward migration (78 days) was nearly twice that of northward migration and data on average migration speed for just two migration legs indicated that it might be lower, 30 and 40 kph being the values recorded. Greater Sandplovers were only tracked on northward migration but seemed to follow a similar migration strategy with a large initial non-stop flight followed by shorter flights and more regular stopovers. Plans are outlined for further analyses and future deployments of geolocators.

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The importance and risk of emerging mosquito borne diseases is going to increase in the European temperate areas due to climate change. The present and upcoming climates of Transdanubia seem to be suitable for the main vector of Chikungunya virus, the Asian tiger mosquito, Aedes albopictus Skuse (syn. Stegomyia albopicta). West Nile fever is recently endemic in Hungary. We used climate envelope modeling to predict the recent and future potential distribution/occurrence areas of the vector and the disease. We found that climate can be sufficient to explain the recently observed area of A. albopictus, while in the case of West Nile fever, the migration routes of reservoir birds, the run of the floodplains, and the position of lakes are also important determinants of the observed occurrence.

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Life history theory suggests that species experiencing high extrinsic mortality rates allocate more resources toward reproduction relative to self-maintenance and reach maturity earlier ('fast pace of life') than those having greater life expectancy and reproducing at a lower rate ('slow pace of life'). Among birds, many studies have shown that tropical species have a slower pace of life than temperate-breeding species. The pace of life has been hypothesized to affect metabolism and, as predicted, tropical birds have lower basal metabolic rates (BMR) than temperate-breeding birds. However, many temperate-breeding Australian passerines belong to lineages that evolved in Australia and share 'slow' life-history traits that are typical of tropical birds. We obtained BMR from 30 of these 'old-endemics' and ten sympatric species of more recently arrived passerine lineages (derived from Afro-Asian origins or introduced by Europeans) with 'faster' life histories. The BMR of 'slow' temperate-breeding old-endemics was indistinguishable from that of new-arrivals and was not lower than the BMR of 'fast' temperate-breeding non-Australian passerines. Old-endemics had substantially smaller clutches and longer maximal life spans in the wild than new arrivals, but neither clutch size nor maximum life span was correlated with BMR. Our results suggest that low BMR in tropical birds is not functionally linked to their 'slow pace of life' and instead may be a consequence of differences in annual thermal conditions experienced by tropical versus temperate species.

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Worldwide, most populations of migratory shorebirds are in jeopardy, none more so than those of the East Asian-Australasian Flyway (EAAF). In order to preserve these highly mobile species a detailed understanding of their use of feeding and resting sites along the flyway is required. In this study we used light-level geolocators and new analytical tools to reveal individual breeding locations and migration routes of 13 Sanderlings (Calidris alba) that spend their non-breeding season in South Australia. We then used these individual migration routes to identify the timing and location of important stopping areas and compared this with assessments based on resightings of leg-flagged birds and count data. During both northward and southward migration, Sanderlings were found to make extensive use of five main areas of the Chinese coastline, the Yellow Sea and the northern end of the Sakhalin Peninsula. Insights gained from the individual migration routes highlight inherent biases in using only count and resighting data to identify important feeding and resting sites along the Flyway. These findings suggest that data on individual movements may be crucial to effective conservation planning of shorebirds in the EAAF and elsewhere in the world.

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Major South-East Asian city-regions have experienced considerable physical, economic and social transformations during the past three decades. The rapid pace of globalisation and economic restructuring has resulted in these city-regions receiving the full impact of urbanisation pressures. In an attempt to ease these pressures, city-regions such as Bangkok, Seoul, Tokyo, Taipei, Hong Kong, Singapore and Kuala Lumpur have advocate growth management approaches giving particular interest to urban sustainability. These approaches promote efforts to achieve the triple bottom line sustainability by balancing economic and social development, and environmental protection, and putting more emphasis on compact and optimum development of urban forms. This paper evaluates the case of two South-East Asian city-regions, Kuala Lumpur and Hong Kong, and assesses their experiences in managing their urban forms whilst promoting sustainable patterns of urban development. The findings show that sustainable urban development initiatives employing a top down approach has yielded encouraging results in these case study city-regions. However the need for a more concerted effort towards the overall sustainability agenda still remains vital.

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An exploration of issues of Asian masculinity in white cultures, integrating film and literary analysis, autobiography and postcolonial theory.

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In this paper we respond to calls for an institution-based perspective on strategy. With its emphasis upon mimetic, coercive, and normative isomorphism, institutional theory has earned a deterministic reputation and seems an unlikely foundation on which to construct a theory of strategy. However, a second movement in institutional theory is emerging that gives greater emphasis to creativity and agency. We develop this approach by highlighting co-evolutionary processes that are shaping the varieties of capitalism (VoC) in Asia. To do so, we examine the extent to which the VoC model can be fruitfully applied in the Asian context. In the spirit of the second movement of institutional theory, we describe three processes in which firm strategy collectively and intentionally feeds back to shape institutions: (1) filling institutional voids, (2) retarding institutional innovation, and (3) deploying institutional escape. We outline the key contributions contained in the articles of this Special Issue and discuss a research agenda generated by the VoC perspective.

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Industrial employment growth has been one of the most dynamic areas of expansion in Asia; however, current trends in industrialised working environments have resulted in greater employee stress. Despite research showing that cultural values affect the way people cope with stress, there is a dearth of psychometrically established tools for use in non-Western countries to measure these constructs. Studies of the "Way of Coping Checklist-Revised" (WCCL-R) in the West suggest that the WCCL-R has good psychometric properties, but its applicability in the East is still understudied. A confirmatory factor analysis (CFA) is used to validate the WCCL-R constructs in an Asian population. This study used 1,314 participants from Indonesia, Sri Lanka, Singapore, and Thailand. An initial exploratory factor analysis revealed that original structures were not confirmed; however, a subsequent EFA and CFA showed that a 38-item, five-factor structure model was confirmed. The revised WCCL-R in the Asian sample was also found to have good reliability and sound construct and concurrent validity. The 38-item structure of the WCCL-R has considerable potential in future occupational stress-related research in Asian countries.

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This project utilises creative practice as research, and involves writing and discussing four sample episodes of a proposed six-part dramatic, black-comedy1 television mini-series titled The New Lows. Combined, the creative project and accompanying exegesis seeks to illuminate and interrogate some of the inherent concerns, pitfalls and politics encountered in writing original Asian-Australian characters for television. Moreover, this thesis seeks to develop and deliberate on characters that would expand, shift and extend concepts of stereotyping and authenticity as they are used in creative writing for television. The protagonists of The New Lows are the contemporary and dysfunctional Asian-Australian Lo family: the Hong Kong immigrants John and Dorothy, and their Australian-born children Wendy, Simon and Tommy. Collectively, they struggle to manage the family business: a decaying suburban Chinese restaurant called Sunny Days, which is stumbling towards imminent commercial death. At the same time, each of the characters must negotiate their own personal catastrophes, which they hide from fellow family members out of shame and fear. Although there is a narrative arc to the series, I have also endeavoured to write each episode as a selfcontained story. Written alongside the creative works is an exegetical component. Through the paradigm of Asian-Australian studies, the exegesis examines the writing process and narrative content of The New Lows, alongside previous representations of Asians on Australian and international television and screen. Concepts discussed include stereotype, ethnicity, otherness, hybridity and authenticity. However, the exegesis also seeks to question the dominant cultural paradigms through which these issues are predominantly discussed. These investigations are particularly relevant, since The New Lows draws upon a suite of characters commonly considered to be stereotypical in Asian-Australian representations.

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Thirteen papers examine Asian and European experiences with developing national and city policy agendas around cultural and creative industries. Papers discuss policy transfer and the field of the cultural and creative industries--what can be learned from Europe; creative industries across cultural borders--the case of video games in Asia; spaces of culture and economy--mapping the cultural-creative cluster landscape; beyond networks and relations--toward rethinking creative cluster theory; the capital complex--Beijing's new creative clusters; the European creative class and regional development--how relevant Richard Florida's theory is for Europe; getting out of place--the mobile creative class taking on the local--a U.K. perspective on the creative class; Asian cities and limits to creative capital theory; the creative industries, governance, and economic development--a U.K. perspective; Shanghai's emergence into the global creative economy; Shanghai moderne--creative economy in a creative city?; urbanity as a political project--toward post-national European cities; and alternative policies in urban innovation. Contributors include economists. Kong is with the Department of Geography at the National University of Singapore. O'Connor is at Queensland University of Technology. Index.

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Genetic polymorphisms in hepatically expressed UGT1A1 and UGT1A9 contribute to the interindividual variability i-n irinotecan disposition and toxicity. We screened UGT1A1 (UGT1A1*60, g.−3140G>A, UGT1A1*28 and UGT1A1*6) and UGT1A9 (g.−118(T)9>10 and I399C>T) genes for polymorphic variants in the promoter and coding regions, and the genotypic effect of UGT1A9 I399C>T polymorphism on irinotecan disposition in Asian cancer patients was investigated. Blood samples were collected from 45 patients after administration of irinotecan as a 90 min intravenous infusion of 375 mg/m2 once in every 3 weeks. Genotypic–phenotypic correlates showed that cancer patients heterozygous or homozygous for the I399C>T allele had approximately 2-fold lower systemic exposure to SN-38 (P<0.05) and a trend towards a higher relative extent of glucuronidation (REG) of SN-38 (P>0.05). UGT1A1–1A9 diplotype analysis showed that patients harbouring the H1/H2 (TG6GT10T/GG6GT9C) diplotype had 2.4-fold lower systemic exposure to SN-38 glucuronide (SN-38G) compared with patients harbouring the H1/H5 (TG6GT10T/GG6GT10C) diplotype (P=0.025). In conclusion, this in vivo study supports the in vitro findings of Girard et al. and suggests that the UGT1A9 I399C>T variant may be an important glucuronidating allele affecting the pharmacokinetics of SN-38 and SN-38G in Asian cancer patients receiving irinotecan chemotherapy.

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What is the responsibility of schools in managing student mental health in the aftermath of global mega-disasters that saturate the media? Here, the focus is on the Asian tsunami but the same question can be asked in relation to other disturbing events, such as September 11, Australian bushfires with local fatalities and the Iraq War.