41 resultados para habitat utilization


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Marsupials exhibit great diversity in ecology and morphology. However, compared to their sister group, the placental mammals, our understanding of many aspects of marsupial evolution remains limited. We use 101 mitochondrial genomes and data from 26 nuclear loci to reconstruct a dated phylogeny including 97% of extant genera and 58% of modern marsupial species. This tree allows us to analyze the evolution of habitat preference and geographic distributions of marsupial species through time. We found a pattern of mesic-adapted lineages evolving to use more arid and open habitats, which is broadly consistent with regional climate and environmental change. However, contrary to the general trend, several lineages subsequently appear to have reverted from drier to more mesic habitats. Biogeographic reconstructions suggest that current views on the connectivity between Australia and New Guinea/Wallacea during the Miocene and Pliocene need to be revised. The antiquity of several endemic New Guinean clades strongly suggests a substantially older period of connection stretching back to the Middle Miocene, and implies that New Guinea was colonized by multiple clades almost immediately after its principal formation.

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Purpose – The purpose of this paper is to examine empirically, an industry development paradox, using embryonic literature in the area of strategic supply chain management, together with innovation management literature. This study seeks to understand how, forming strategic supply chain relationships, and developing strategic supply chain capability, influences beneficial supply chain outcomes expected from utilizing industry-led innovation, in the form of electronic business solutions using the internet, in the Australian beef industry. Findings should add valuable insights to both academics and practitioners in the fields of supply chain innovation management and strategic supply chain management, and expand knowledge to current literature. Design/methodology/approach – This is a quantitative study comparing innovative and non-innovative supply chain operatives in the Australian beef industry, through factor analysis and structural equation modeling using PAWS Statistical V18 and AMOS V18 to analyze survey data from 412 respondents from the Australian beef supply chain. Findings – Key findings are that both innovative and non-innovative supply chain operators attribute supply chain synchronization as only a minor indicator of strategic supply chain capability, contrary to the literature; and they also indicate strategic supply chain capability has a minor influence in achieving beneficial outcomes from utilizing industry-led innovation. These results suggest a lack of coordination between supply chain operatives in the industry. They also suggest a lack of understanding of the benefits of developing a strategic supply chain management competence, particularly in relation to innovation agendas, and provides valuable insights as to why an industry paradox exists in terms of the level of investment in industry-led innovation, vs the level of corresponding benefit achieved. Research limitations/implications – Results are not generalized due to the single agribusiness industry studied and the single research method employed. However, this provides opportunity for further agribusiness studies in this area and also studies using alternate methods, such as qualitative, in-depth analysis of these factors and their relationships, which may confirm results or produce different results. Further, this study empirically extends existing theoretical contributions and insights into the roles of strategic supply chain management and innovation management in improving supply chain and ultimately industry performance while providing practical insights to supply chain practitioners in this and other similar agribusiness industries. Practical implications – These findings confirm results from a 2007 research (Ketchen et al., 2007) which suggests supply chain practice and teachings need to take a strategic direction in the twenty-first century. To date, competence in supply chain management has built up from functional and process orientations rather than from a strategic perspective. This study confirms that there is a need for more generalists that can integrate with various disciplines, particularly those who can understand and implement strategic supply chain management. Social implications – Possible social implications accrue through the development of responsible government policy in terms of industry supply chains. Strategic supply chain management and supply chain innovation management have impacts to the social fabric of nations through the sustainability of their industries, especially agribusiness industries which deal with food safety and security. If supply chains are now the competitive weapon of nations then funding innovation and managing their supply chain competitiveness in global markets requires a strategic approach from everyone, not just the industry participants. Originality/value – This is original empirical research, seeking to add value to embryonic and important developing literature concerned with adopting a strategic approach to supply chain management. It also seeks to add to existing literature in the area of innovation management, particularly through greater understanding of the implications of nations developing industry-wide, industry-led innovation agendas, and their ramifications to industry supply chains.

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Two ultrasound survey methods were used to determine the presence and activity patterns of New Zealand long-tailed bats (Chalinolobus tuberculatus) in the city of Hamilton. First, 13 monthly surveys conducted at 18 green spaces found C. tuberculatus in only one urban forest reserve, Hammond Bush, where they were found consistently throughout the year. Bat activity was strongly related to temperature. Second, twice-yearly citywide surveys conducted over 2 years determined the distribution and habitat associations of C. tuberculatus. Bats were found only in the southern part of the city and were strongly associated with the Waikato River. Bat activity was negatively correlated with housing and street light density and positively correlated with topographical complexity. In Hamilton, topographical complexity indicates the presence of gullies. Gullies probably provide foraging and roosting opportunities and connect the river to distant forest patches. These results suggest that urban habitats can be useful for bats if gullies can link these to distant habitat fragments.

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Individuals' home ranges are constrained by resource distribution and density, population size, and energetic requirements. Consequently, home ranges and habitat selection may vary between individuals of different sex and reproductive conditions. Whilst home ranges of bats are well-studied in native habitats, they are often not well understood in modified landscapes, particularly exotic plantation forests. Although Chalinolobus tuberculatus (Vespertilionidae, Chiroptera) are present in plantation forests throughout New Zealand their home ranges have only been studied in native forest and forest-agricultural mosaic and no studies of habitat selection that included males had occurred in any habitat type. Therefore, we investigated C. tuberculatus home range and habitat selection within exotic plantation forest. Home range sizes did not differ between bats of different reproductive states. Bats selected home ranges with higher proportions of relatively old forest than was available. Males selected edges with open unplanted areas within their home ranges, which females avoided. We suggest males use these edges, highly profitable foraging areas with early evening peaks in invertebrate abundance, to maintain relatively low energetic demands. Females require longer periods of invertebrate activity to fulfil their needs so select older stands for foraging, where invertebrate activity is higher. These results highlight additional understanding gained when data are not pooled across sexes. Mitigation for harvest operations could include ensuring that areas suitable for foraging and roosting are located within a radius equal to the home range of this bat species.

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The use of bat detectors to monitor bat activity is common. Although several papers have compared the performance of different brands, none have dealt with the effect of different habitats nor have they compared narrow- and broad-band detectors. In this study the performance of four brands of ultrasonic bat detector, including three narrowband and one broad-band model, were compared for their ability to detect a 40 kHz continuous sound of variable amplitude along 100 metre transects. Transects were laid out in two contrasting bat habitat types: grassland and forest. Results showed that the different brands of detector differed in their ability to detect the source in terms of maximum and minimum detectable distance of the source. The rate of sound degradation with distance as measured by each brand was also different. Significant differences were also found in the performance of different brands in open grassland versus deep forest. No significant differences were found within any brand of detector. Though not as sensitive as narrow-band detectors, broad-band models hold an advantage in their ability to identify species where several species are found sympatrically.

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This paper overviews the development of a vision-based AUV along with a set of complementary operational strategies to allow reliable autonomous data collection in relatively shallow water and coral reef environments. The development of the AUV, called Starbug, encountered many challenges in terms of vehicle design, navigation and control. Some of these challenges are discussed with focus on operational strategies for estimating and reducing the total navigation error when using lower-resolution sensing modalities. Results are presented from recent field trials which illustrate the ability of the vehicle and associated operational strategies to enable rapid collection of visual data sets suitable for marine research applications.

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This paper develops a dynamic model for cost-effective selection of sites for restoring biodiversity when habitat quality develops over time and is uncertain. A safety-first decision criterion is used for ensuring a minimum level of habitats, and this is formulated in a chance-constrained programming framework. The theoretical results show; (i) inclusion of quality growth reduces overall cost for achieving a future biodiversity target from relatively early establishment of habitats, but (ii) consideration of uncertainty in growth increases total cost and delays establishment, and (iii) cost-effective trading of habitat requires exchange rate between sites that varies over time. An empirical application to the red listed umbrella species - white-backed woodpecker - shows that the total cost of achieving habitat targets specified in the Swedish recovery plan is doubled if the target is to be achieved with high reliability, and that equilibrating price on a habitat trading market differs considerably between different quality growth combinations. © 2013 Elsevier GmbH.

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Aim: To quantify the consequences of major threats to biodiversity, such as climate and land-use change, it is important to use explicit measures of species persistence, such as extinction risk. The extinction risk of metapopulations can be approximated through simple models, providing a regional snapshot of the extinction probability of a species. We evaluated the extinction risk of three species under different climate change scenarios in three different regions of the Mexican cloud forest, a highly fragmented habitat that is particularly vulnerable to climate change. Location: Cloud forests in Mexico. Methods: Using Maxent, we estimated the potential distribution of cloud forest for three different time horizons (2030, 2050 and 2080) and their overlap with protected areas. Then, we calculated the extinction risk of three contrasting vertebrate species for two scenarios: (1) climate change only (all suitable areas of cloud forest through time) and (2) climate and land-use change (only suitable areas within a currently protected area), using an explicit patch-occupancy approximation model and calculating the joint probability of all populations becoming extinct when the number of remaining patches was less than five. Results: Our results show that the extent of environmentally suitable areas for cloud forest in Mexico will sharply decline in the next 70 years. We discovered that if all habitat outside protected areas is transformed, then only species with small area requirements are likely to persist. With habitat loss through climate change only, high dispersal rates are sufficient for persistence, but this requires protection of all remaining cloud forest areas. Main conclusions: Even if high dispersal rates mitigate the extinction risk of species due to climate change, the synergistic impacts of changing climate and land use further threaten the persistence of species with higher area requirements. Our approach for assessing the impacts of threats on biodiversity is particularly useful when there is little time or data for detailed population viability analyses. © 2013 John Wiley & Sons Ltd.

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Traditional perceptions of the human-animal relationship in the urban context typically see the spatial rejection of wildlife from the built environment and limiting of biodiversity conservation programs to areas of natural reserve. As urban growth places further spatial demands on natural habitat and contributes to continued global biodiversity loss, the recently introduced conservation approach of reconciliation ecology makes a call promoting ecological stewardship through embedding wildlife habitat within human dominated areas. Coinciding with this, the architectural sphere has seen a recent trend of design investigation addressing artificial animal habitat as features of the built environment. Although these precedents are currently a niche and scattered trend they show potential to address the human-animal dualism challenging the framework of reconciliation ecology. This research explores the role design plays in influencing perceptions of urban wildlife habitat, particularly considering the need to create and communicate value around wildlife biodiversity as a component of urban cultural place-making and ecological literacy. The study purpose sets out to establish a set of approaches and cultural preferences with which to direct further classification and development of this architectural trend. Brisbane is utilised as a case study city, as a locale containing proximities of relatively high wildlife and human populations in an urban setting and an established legislative biodiversity heritage and ethic. Through use of a qualitative and quantitative questionnaire targeting Brisbane residents, the research methodology established that although respondents perceptions generally aligned with traditional prejudice against wildlife around human buildings, artificial habitat intervention would be supported within the CBD provided it allowed for adequate distancing of humans from wildlife and conformed with contextual surroundings, or otherwise addressed habitat through redevelopment at an urban scale. As such further research directions for artificial habitat should focus on integration of artificial habitat as a component of façade design or green infrastructure programs.

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Background Understanding how different socioeconomic indicators are associated with transport modes provide insight into which interventions might contribute to reducing socioeconomic inequalities in health. The purpose of this study was to examine associations between neighbourhood-level socioeconomic disadvantage, individual-level socioeconomic position (SEP) and usual transport mode. Methods This investigation included 11,036 residents from 200 neighbourhoods in Brisbane, Australia. Respondents self-reported their usual transport mode (car or motorbike, public transport, walking or cycling). Indicators for individual-level SEP were education, occupation, and household income; and neighbourhood disadvantage was measured using a census-derived index. Data were analysed using multilevel multinomial logistic regression. High SEP respondents and residents of the most advantaged neighbourhoods who used a private motor vehicle as their usual form of transport was the reference category. Results Compared with driving a motor vehicle, the odds of using public transport were higher for white collar employees (OR1.68, 95%CrI 1.41-2.01), members of lower income households (OR 1.71 95%CrI 1.25-2.30), and residents of more disadvantaged neighbourhoods (OR 1.93, 95%CrI 1.46-2.54); and lower for respondents with a certificate-level education (OR 0.60, 95%CrI 0.49-0.74) and blue collar workers (OR 0.63, 95%CrI 0.50-0.81). The odds of walking for transport were higher for the least educated (OR 1.58, 95%CrI 1.18-2.11), those not in the labour force (OR 1.94, 95%CrI 1.38-2.72), members of lower income households (OR 2.10, 95%CrI 1.23-3.64), and residents of more disadvantaged neighbourhoods (OR 2.73, 95%CrI 1.46-5.24). The odds of cycling were lower among less educated groups (OR 0.31, 95% CrI 0.19-0.48). Conclusion The relationships between socioeconomic characteristics and transport modes are complex, and provide challenges for those attempting to encourage active forms of transportation. Further work is required exploring the individual- and neighbourhood-level mechanisms behind transport mode choice, and what factors might influence individuals from different socioeconomic backgrounds to change to more active transport modes.

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Primary brain tumors are associated with significant physical, cognitive and psychosocial changes. Although treatment guidelines recommend offering multidisciplinary rehabilitation and support services to address patients’ residual deficits, the extent to which patients access such services is unclear. This study aimed to assess patients’ supportive care needs early after diagnosis, and quantify service awareness, referral and utilization. A population-based sample of 40 adults recently diagnosed with primary brain tumors was recruited through the Queensland Cancer Registry, representing 18.9% of the eligible population of 203 patients. Patients or carer proxies completed surveys of supportive care needs at baseline (approximately three months after diagnosis) and three months later. Descriptive statistics summarized needs and service utilization, and linear regression identified predictors of service use. Unmet supportive care needs were highest at baseline for all domains, and highest for the physical and psychological needs domains at each time point. At follow-up, participants reported awareness of, referral to, and use of 32 informational, support, health professional or practical services. All or almost all participants were aware of at least one informational (100%), health professional (100%), support (97%) or practical service (94%). Participants were most commonly aware of speech therapists (97%), physiotherapists (94%) and diagnostic information from the internet (88%). Clinician referrals were most commonly made to physiotherapists (53%), speech therapists (50%) and diagnostic information booklets (44%), and accordingly, participants most commonly used physiotherapists (56%), diagnostic information booklets (47%), diagnostic information from the internet (47%), and speech therapists (43%). Comparatively low referral to and use of psychosocial services may limit patients’ abilities to cope with their condition and the changes they experience.