196 resultados para Ham -- Conservation


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Fire is both a widespread natural disturbance that affects the distribution of species and a tool that can be used to manage habitats for species. Knowledge of temporal changes in the occurrence of species after fire is essential for conservation management in fire-prone environments. Two key issues are: whether postfire responses of species are idiosyncratic or if multiple species show a limited number of similar responses; and whether such responses to time since fire can predict the occurrence of species across broad spatial scales. We examined the response of bird species to time since fire in semiarid shrubland in southeastern Australia using data from surveys at 499 sites representing a 100-year chronosequence. We used nonlinear regression to model the probability of occurrence of 30 species with time since fire in two vegetation types, and compared species' responses with generalized response shapes from the literature. The occurrence of 16 species was significantly influenced by time since fire: they displayed six main responses consistent with generalized response shapes. Of these 16 species, 15 occurred more frequently in mid- or later-successional vegetation (>20 years since fire), and only one species occurred more often in early succession (<5 years since fire). The models had reasonable predictive ability for eight species, some predictive ability for seven species, and were little better than random for one species. Bird species displayed a limited range of responses to time since fire; thus a small set of fire ages should allow the provision of habitat for most species. Postfire successional changes extend for decades and management of the age class distribution of vegetation will need to reflect this timescale. Response curves revealed important seral stages for species and highlighted the importance of mid- to late-successional vegetation (>20 years). Although time since fire clearly influences the distribution of numerous bird species, predictive models of the spatial distribution of species in fire-prone landscapes need to incorporate other factors in addition to time since fire.

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Ecological monitoring is widely used to measure change through time in ecosystems. The current extinction crisis has resulted in a wealth of monitoring programs focussed on tracking the status of threatened species, and the perceived importance of monitoring has seen it become the cornerstone of many biodiversity conservation programs. However, many monitoring programs fail to produce useful outcomes due to inherent flaws. Here we use a monitoring program from south-eastern Australia as a case study to illustrate the potential of such endeavours. The threatened carnivorous marsupial, the brush-tailed phascogale (Phascogale tapoatafa), has been monitored at various locations between 2000 and 2010. We present strong evidence for a decline in relative abundance during this period, and also describe relationships with environmental variables. These results provide insights likely to be valuable in guiding future management of the species. In the absence of the monitoring program, informed management would not be possible. While early detection of population declines is important, knowledge of the processes driving such declines is required for effective intervention. We argue that monitoring programs will be most effective as a tool for enhanced conservation management if they test specific hypotheses relating to changes in population trajectories. Greater emphasis should be placed on rigorous statistical analysis of monitoring datasets in order to capitalise on the resources devoted to monitoring activities. Many datasets are likely to exist for which careful analysis of results would have benefits for determining management directions.

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Information based on the accurate identification of species is a vital component for achieving successful outcomes of biodiversity conservation and management. It is difficult to manage species that are poorly known or that are misidentified with other similar species. This is particularly problematic for rare and threatened species. Species that are listed under endangered species classification schemes need to be identified accurately and categorised correctly so that conservation efforts are appropriately allocated. In Australia, the emballonurid Saccolaimus saccolaimus is currently listed as ‘Critically Endangered’. On the basis of new observations and existing museum specimens, we used a combination of genetic (mitochondrial DNA sequence) and morphological (pelage characteristics, dig III : phalanx I length ratio, inter-upper canine distance) analyses to identify six new geographic records for S. saccolaimus, comprising ~100 individuals. Our analyses also suggested that there are likely to be more records in museum collections misidentified as S. flaviventris specimens. The external morphological similarities to S. flaviventris were addressed and genetic, morphological and echolocation analyses were used in an attempt to provide diagnostic characters that can be used to readily identify the two species in the field. We recommend genetic testing of all museum specimens of Australian Saccolaimus to clarify species’ distributions and provide data for reassessing the conservation status for both S. saccolaimus and S. flaviventris. Museum curators, taxonomists and wildlife managers need to be aware of potential species misidentifications, both in the field and laboratory. Misidentifications that result in misclassification of both threatened and non-threatened species can have significant implications.

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Recreational use of beaches may threaten some beach-nesting shorebirds in southern Australia. Temporary Beach Closures, comprized of a 50 x 25 m exclusion zone around a shorebird nest, represent a promising technique for altering human behaviour by reducing both disturbance to birds and inadvertent crushing of eggs by beach visitors. We assessed whether three commonly employed configurations of Temporary Beach Closures (sign, fence, and warden) were effective at: (1) achieving compliance among beach visitors, and (2) reducing egg-crushing rates. Overall, 93.7% of beach visitors complied with all Temporary Beach Closures, resulting in a reduction in egg-crushing rates within, as opposed to adjacent to, Temporary Beach Closures. Levels of compliance were high in all Temporary Beach Closure configurations (88.0-99.4%), and similar levels of compliance were achieved within the three configurations. Human compliance was highest for females and when the density of beach-users was higher, while individuals aged <20 and >61 years were less likely to comply with Temporary Beach Closures. Despite an increased probability of compliance on high density beaches, this did not translate into a reduction in egg crushing rates on such beaches, because the overall number of noncompliant individuals remained higher. We conclude any Temporary Beach Closure configuration is meritorious, and that their use on high and low-use recreational beaches will benefit breeding shorebirds by reducing the rate of egg-crushing. Targeting demographics that display lower levels of compliance, such as men, young people (i.e. <21), and older people (i.e. >60), may further improve the effectiveness of Temporary Beach Closures in enhancing the conservation of shorebirds.

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The fisheries sector in the course of the last three decades have been transformed from a developed country to a developing country dominance. Aquaculture, the farming of waters, though a millennia old tradition during this period has become a significant contributor to food fish production, currently accounting for nearly 50 % of global food fish consumption; in effect transforming our dependence from a hunted to a farmed supply as for all our staple food types. Aquaculture and indeed the fisheries sector as a whole is predominated in the developing countries, and accordingly the development strategies adopted by the sector are influenced by this. Aquaculture also being a newly emerged food production sector has being subjected to an increased level of public scrutiny, and one of the most contentious aspects has been its impacts on biodiversity. In this synthesis an attempt is made to assess the impacts of aquaculture on biodiversity. Instances of major impacts on biodiversity conservation arising from aquaculture, such as land use, effluent discharge, effects on wild populations, alien species among others are highlighted and critically examined. The influence of paradigm changes in development strategies and modern day market forces have begun to impact on aquaculture developments. Consequently, improvements in practices and adoption of more environmentally friendly approaches that have a decreasing negative influence on biodiversity conservation are highlighted. An attempt is also made to demonstrate direct and or indirect benefits of aquaculture, such as through being a substitute to meet human needs for food, particularly over-exploited and vulnerable fish stocks, and for other purposes (e.g. medicinal ingredients), on biodiversity conservation, often a neglected entity.

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Although marine protected areas (MPAs) are a common conservation strategy, these areas are often designed with little prior knowledge of the spatial behaviour of the species they are designed to protect. Currently, the Coral Sea area and its seamounts (north-east Australia) are under review to determine if MPAs are warranted. The protection of sharks at these seamounts should be an integral component of conservation plans. Therefore, knowledge on the spatial ecology of sharks at the Coral Sea seamounts is essential for the appropriate implementation of management and conservation plans. Acoustic telemetry was used to determine residency, site fidelity and spatial use of three shark species at Osprey Reef: whitetip reef sharks Triaenodon obesus, grey reef sharks Carcharhinus amblyrhynchos and silvertip sharks Carcharhinus albimarginatus. Most individuals showed year round residency at Osprey Reef, although five of the 49 individuals tagged moved to the neighbouring Shark Reef (∼14 km away) and one grey reef shark completed a round trip of ∼250 km to the Great Barrier Reef. Additionally, individuals of white tip and grey reef sharks showed strong site fidelity to the areas they were tagged, and there was low spatial overlap between groups of sharks tagged at different locations. Spatial use at Osprey Reef by adult sharks is generally restricted to the north-west corner. The high residency and limited spatial use of Osprey Reef suggests that reef sharks would be highly vulnerable to targeted fishing pressure and that MPAs incorporating no-take of sharks would be effective in protecting reef shark populations at Osprey and Shark Reef.

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Bali is internationally recognized as an island possessing a beautiful natural landscape as well as a unique culture. The natural qualities of its mountains, lakes, rivers, rice terrace fields with subak irrigation make Bali an important tourism destination. Cultural Tourism is integral in Bali’s tourism industry providing the basic capital for development1. The social condition of this society that is strongly characterized by religious beliefs, and its nature and ecology also supports this. The conservation and maintenance of this traditional landscape is often forgotten because of government agendas to implement cultural city programs aimed at encouraging tourism development. Despite this, the government is now supporting the program of ‘Bali toward Garden Island’, which aims to sustain the physical and cultural environment of the island towards conservation of its landscape. The implementation of this program includes attention to universal, societal and cultural values as unity indicators, of which the landscape planning of the Balinese characteristics and traditions cannot be separated. Landscape planning is integral in this initiative of character defining the region.

Globalisation is increasingly becoming one of the most important discussions amongst the Balinese people. It has become a national concern about the changes implicating Bali’s environment. Urbanisation, population growth, ribbon development, migration and consumption of energy are important imperatives and necessary evils for growing cities. These imperatives are creating the sprawl of building planning, development information, loss of open spaces, as well as the decline of the identity of cities. Places such as Denpasar City are struggling with increasing population at a rate of 1.94% per year that is causing increase in housing and public facilities demanded by both residents and ex-patriates. Thus land associated with the city has been lost to the rapid development of this cultural landscape.

This paper examines the Balinese traditional landscape and its role in encouraging tourism development that based on the Balinese culture and its ecology. The paper focuses on the planning of city landscape appearance characteristics and seeks to test and adopt the terms ‘creative conservation’ and ‘eco city concept’. By conserving the most important philosophy of the Balinese Tri Hita Karana Concept will better inform all aspects of city development in Bali. This study seeks to offer guidance for the legitimate use of landscape planning especially for city development in Bali.

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Several authors have recently argued that dingoes could be used to help conserve biodiversity in Australia. Fleming et al. (2012) [Australian Mammalogy 34, 119–131] offer the alternative view that restoration of dingo predation is unlikely to help native species, and is more likely to do harm. We think many of the arguments used by Fleming et al. to reach that conclusion are either unsound or beside the point, and we explain why.

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There has been a dramatic increase in the area that is within the National Reserve System since 2000 – from around 60 million hectares to around 100 million in 2008. This dramatic increase can be attributed to Indigenous Protected Areas and the acquisition of private or leasehold land for either addition to the public protected area estate or management as private protected areas. This growth has also been strategic, increasingly the reservation status of the most underreserved bioregions. However, the reality is the land acquisition has slowed since the global financial crisis of the late 2000s and this has led to new models with different partners coming to the fore. This chapter highlights one of those new models – the acquisition of Fish River Station in the Northern Territory for conservation.