123 resultados para Bear Island Fan


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The reproductive ecology of the swamp antechinus Antechinus minimus, a small dasyurid (Dasyuridae) marsupial with obligate male semelparity, was investigated in populations inhabiting the mainland coast and on a nearby offshore island in south-eastern Australia. The size and sex ratios of litters, individual body mass and size, timing of births and female longevity were determined from live-trapped animals. The island population had significantly smaller litter sizes and greater adult body mass in comparison with the mainland population. This is consistent with features of the ‘island syndrome’, which predicts directional selection for these traits in high-density populations with reduced extrinsic mortality. However, inter-annual variability in litter sizes in the island population suggests that litter size is more responsive to fluctuating local conditions, such as population density, which is likely to affect food availability, rather than directional genetic changes. In contrast with other antechinus species, biased sex ratios were not evident. In addition, large variations of the timing of births were estimated at both sites and these appear to be related to seasonal conditions such as autumn rainfall and female body mass before mating.

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Aid flows to small island developing states (SIDS) are enormous by international standards when compared to the size of their economies. Yet these countries face many severe economic challenges and many have experienced declines in the living standards of their citizens. This paper looks at the impact of aid on what is treated as a necessary precondition for improvements in living standards, typically defined. Specifically, it examines the impact of foreign aid on real per capita income growth in SIDS by econometrically analysing cross-country data for the period 1980 to 2004. A variety of econometric techniques and measures of aid are used. Results suggest that foreign aid is effective at spurring economic growth but with diminishing returns.

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Small Island Developing States (SIDS) are very different to other developing countries. Relative to GDP they have the highest levels of foreign trade and aid receipts of all developing countries. Remittances from abroad are a far more important source of income for SIDS, and some depend very heavily on export revenues. The quality of governance varies tremendously among SIDS, they are over-represented among countries classified as fragile states and many are prone to state failure. These and other factors combine to make SIDS highly vulnerable to external economic shocks. Achieving development in SIDS is as a consequence an especially complex task that requires an understanding of the roles played by aid, trade, remittances and governance in these countries. This paper looks at these issues, along with providing various stylised facts about SIDS. In so doing it serves as a background and broad contextual setting for the papers that follow in this Special Issue on 'Fragility and Development in Small Island Developing States'.

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This paper explores the palaeoclimatic significance of a fossil plant and insect record from Yarra Creek, on King Island, between Tasmania and the Australian mainland. The record dates, based upon a thermoluminescence chronology and other evidence, to Marine Isotope Stage 5 (MIS 5); the exact timing is impossible to ascertain given the resolution of the thermoluminescence results and the presence of an unconformity in the dated section. The presence of a cool-temperate rainforest flora, outside its modern range, and other independent evidence, suggest the sequence may represent the last interglacial (MIS 5e) rather than a later MIS 5 substage. Using coexistence methods that compare modern climatic ranges of the taxa in the assemblage we reconstruct independent beetle and plant based annual and seasonal temperate and precipitation parameters. The results imply the assemblage was deposited under a wetter summer climate and suggest conditions of enhanced temperature seasonality. It is probable that enhanced temperature seasonality is a methodological artefact reflecting the rarity of extremely equable climates (like King Island) in modern climate space. This would indicate a limitation of most methods of palaeoclimatic reconstruction that rely on modern datasets – it is only possible to reconstruct past climates as being within the range of values in that currently exist in modern climate space.

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Although the recent history of human colonisation and impact on Mauritius is well documented, virtually no records of the pre-human native ecosystem exist, making it difficult to assess the magnitude of the changes brought about by human settlement. Here, we describe a 4000-year-old fossil bed at Mare aux Songes (MAS) in south-eastern Mauritius that contains both macrofossils (vertebrate fauna, gastropods, insects and flora) and microfossils (diatoms, pollen, spores and phytoliths). With >250 bone fragments/m2 and comprising 50% of all known extinct and extant vertebrate species (ns = 44) of Mauritius, MAS may constitute the first Holocene vertebrate bone Concentration-Lagerstätte identified on an oceanic volcanic island. Fossil remains are dominated by extinct giant tortoises Cylindraspis spp. (63%), passerines (10%), small bats (7.8%) and dodo Raphus cucullatus (7.1%). Twelve radiocarbon ages [four of them duplicates] from bones and other material suggest that accumulation of fossils took place within several centuries. An exceptional combination of abiotic conditions led to preservation of bones, bone collagen, plant tissue and microfossils. Although bone collagen is well preserved, DNA from dodo and other Mauritian vertebrates has proved difficult. Our analysis suggests that from ca 4000 years ago (4 ka), rising sea levels created a freshwater lake at MAS, generating an oasis in an otherwise dry environment which attracted a diverse vertebrate fauna. Subsequent aridification in the south-west Indian Ocean region may have increased carcass accumulation during droughts, contributing to the exceptionally high fossil concentration. The abundance of floral and faunal remains in this Lagerstätte offers a unique opportunity to reconstruct a pre-human ecosystem on an oceanic island, providing a key foundation for assessing the vulnerability of island ecosystems to human impact.

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Reproductive characteristics of a wildlife population are typically sensitive to changes in environmental conditions and intrinsic factors. Knowledge of these relationships is critical for understanding population dynamics and effective long-term management of a population. We examined temporal variation in reproductive parameters of an abundant, genetically compromised, and high-density population of koalas (Phascolarctos cinereus) on Kangaroo Island, South Australia, over 3 breeding seasons spanning 9 years: November–May of 1997–1998, 2005–2006, and 2006–2007. Timing of the breeding season was consistent between years, but fecundity, sex ratio of young, and the percentage of independent females (those not accompanying a lactating female) , 6 kg varied. Fecundity was lower than in other island populations, suggesting that the quality and distribution of food resources or inbreeding may be impacting the Kangaroo Island population. We did not test for Chlamydophila (synonym =Chlamydia), and clinical signs of this disease were not reported for any of the koalas in this study. However, historical evidence of Chlamydophila-infected koalas on Kangaroo Island exists, and the potential impact of this disease on fecundity warrants further investigation.

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Panel unit root and stationarity tests without structural breaks suggest that for eight Pacific island economies real gross domestic product (GDP) per capita contains a unit root. The panel stationarity test that accommodates structural change in the trend function, however, finds evidence in favour of regimewise trend stationarity. This result points to the importance of taking structural breaks into account. The finding implies that, for the period considered, the permanent secular component of output is dominated by transitory fluctuations accompanied by infrequent changes in the trend function. The only exceptions are Fiji and Kiribati, for which individual stationarity tests with multiple structural breaks suggest that real GDP per capita contains a unit root.

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This article examines the export-led growth and import-led growth hypotheses for a panel of Pacific island countries—namely, Fiji, Papua New Guinea, Solomon Islands, Tonga and Vanuatu—for the period 1982–2004. The modelling is performed using a panel unit root, panel co-integration and panel Granger causality approach. We find bi-directional Granger causality for the panel of Pacific island countries between exports and economic growth, imports and economic growth, and exports and imports. The results suggest that the poor growth performance of many Pacific island countries reflects their poor export performance; however, if the supply-side constraints on exports are removed, there could be a virtuous cycle between economic growth and exports.