151 resultados para Monk seals.


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Deakin University along with the CRC for Coastal Zone, Estuary and Waterway Management, the Glenelg Hopkins CMA and the Marine & Coastal Community Network have formed a partnership to map the benthic habitats at 14 sites across approximately 5% of Victorian State waters. The project is funded through the Federal Government by the Natural Heritage Trust and brings together expertise from universities, government agencies and private enterprise. We will be using hydro-acoustic sonar technologies, towed video camera and remotely operated vehicles to collect information on the types of substrate and bathymetry to derive habitat maps. The coastal fringe of Victoria encompasses rich and diverse ecosystems which support a range of human uses including commercial and recreational fisheries, whale watching, navigation, aquaculture and gas development. The Deakin lead initiative will map from the 10-metre contour (safe ship passage) to the three nautical mile mark for selected regions and will provide a geospatial framework for managing and gaining better understanding of the near-shore marine environment Research products will be used for management, educational and research purposes over the coming years.

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The Australian fur seal (Arctocephalus pusillus doriferus) was severely over-exploited in the 18th and 19th centuries and until relatively recently its population had remained steady at well below estimated presealing levels. However, the population is now increasing rapidly (6%–20% per annum) throughout its range and there is a need to understand its dynamics in order to assess the potential extent and impact of interactions with fisheries. Age distribution (n = 156) and pregnancy rate (n = 110) were determined for adult females collected at a breeding colony on Seal Rocks, southeast Australia, in 1971–1972. Mean ± SE and maximum observed ages were 9.37 ± 0.41 and 20 years (n = 1), respectively. A stochastic modelling approach was used to fit an age distribution to the observed age-structure data and calculate rates of recruitment and adult survival. Annual adult female survival and recruitment rates between 1954 and 1971 were 0.478 ± 0.029 (mean ± SE) and 0.121 ± 0.007, respectively, suggesting that the population was experiencing a decline during the 1960s. The pregnancy rate increased from 78% at 3 years of age to an average of 85% between 4–13 years of age before significantly decreasing in older females (the oldest was 19 years of age). There was no significant effect of body mass or condition on the probability of a female being pregnant (P > 0.5 in both cases) and the nutritional burden of lactation did not appear to affect pregnancy rates or gestational performance. These findings suggest that the low survivorship was due to density-independent effects such as mortality resulting from interactions with fishers, which are known to have been common at the time. The recent increase in the population is consistent with anecdotal evidence that such interactions have decreased as fishing practices have changed.

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Pre-weaning growth rates, body composition, milk consumption and mass gain efficiency were measured in Australian fur seal Arctocephalus pusillus doriferus pups born in two consecutive breeding periods. Australian fur seals have the highest birth mass of any fur seal species (male 8.3 kg; female 7.2 kg). While their absolute pre-weaning growth rate (male 62 g·day−1; female 53 g·day−1) is similar to that of other temperate latitude fur seals, they have the longest birth-mass doubling time of any otariid species (134–136 days). Daily milk consumption increased from 400 g·day−1 (5 MJ·day−1) after birth to 675 g·day−1 (13.7 MJ·day−1) at age 210 day. However, mean mass-specific milk consumption (41 g·kg−1) is substantially lower than in other otariid species (58–70 g·kg−1) and, combined with a low mass gain efficiency (0.12 g·g−1), contributes to the low mass-specific growth rates observed. There were no significant differences in either absolute or mass-specific milk consumption between the sexes. Significant differences, however, were found between the sexes in the body composition of pups with females generally having larger body lipid stores than males for any given mass. Peak milk yield by Australian fur seal females is estimated at 0.60 MJkg−0.75, substantially less than in Antarctic fur seals. The low level of maternal energy transfer in Australian fur seals may reflect the relatively low marine productivity of their foraging areas.

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The metabolism of 52–73-day old Antarctic fur seal pups from Bird Island, South Georgia, was investigated during fasting periods of normal duration while their mothers were at sea foraging. Body mass decreased exponentially with pups losing 3.5–3.8% of body mass per day. Resting metabolic rate also decreased exponentially from 172–197 ml (O2)·min−1 at the beginning of the fast and scaled to Mb0.74 at 2.3 times the level predicted for adult terrestrial mammals of similar size. While there was no significant sex difference in RMR, female pups had significantly higher (F1,18=6.614, P<0.019) mass-specific RMR than male pups throughout the fasting period. Fasting FMR was also significantly (t15=2.37, P<0.035) greater in females (823 kJ·kg−1·d−1) than males (686 kJ·kg−1·d−1). Average protein turnover during the study period was 19.3 g·d−1 and contributed to 5.4% of total energy expenditure, indicating the adoption of a protein-sparing strategy with a reliance on primarily lipid catabolism for metabolic energy. This is supported by observed decreases in plasma BUN, U/C, glucose and triglyceride concentrations, and an increase in β-HBA concentration, indicating that Antarctic fur seals pups adopt this strategy within 2–3 days of fasting. Mean RQ also decreased from 0.77 to 0.72 within 3 days of fasting, further supporting a rapid commencement of protein-sparing. However, RQ gradually increased thereafter to 0.77, suggesting a resumption of protein catabolism which was not substantiated by changes in plasma metabolites. Female pups had higher TBL (%) than males for any given mass, which is consistent with previous findings in this and other fur seal species, and suggests sex differences in metabolic fuel use. The observed changes in plasma metabolites and protein turnover, however, do not support this.

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The author is a Benedictine monk of L’abbaye Sainte-Madeleine du Barroux in France. The original paper (in French) was delivered in July 2001 at a Liturgy Conference held at the Abbey of Notre Dame, Fontgombault, France,
in the presence of the then Joseph Cardinal Ratzinger when Prefect of the Congregation for the Doctrine of the Faith and was later published in the English translated proceedings of the conference edited by Dr Alcuin Reid, Looking Again at the Question of the Liturgy with Cardinal Ratzinger:
Proceedings of the July 2001 Fontgombault Liturgical Conference (St Michael’s Abbey, Farnborough, 2003). The paper here published is revised and translated from the original French especially for The Priest by Professor David Birch (Deakin University, Melbourne) at the invitation of the Editor, with the cooperation of Dom Charbel. The full set of footnotes is available in Reid (Ed.) (2003). Where passages are quoted from Magisterial texts, the Vatican website English translation is given rather than a translation of the French version used in the original paper. Sub-headings are due to the Editor.

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In recent years there has been an increase in community-based monitoring programmes developed and implemented worldwide. This paper describes how the data collected from such a programme could be integrated into a Geographic Information System (GIS) to create temperate subtidal marine habitat maps. A differential Global Positioning System was utilized to accurately record the location of the trained community-based SCUBA diver data. These georeferenced data sets were then used to classify benthic habitats using an aerial photograph and digitizing techniques. This study demonstrated that trained community-based volunteers can collect data that can be utilized within a GIS to create reliable and cost-effective maps of shallow temperate subtidal rocky reef systems.

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The vocal repertoire, structure, and behavioral context of airborne vocalizations produced by Australian fur seals (Arctocephalus pusillus doriferus) are described using recordings made at a breeding colony on Kanowna Island, Bass Strait, Australia. The study identified six different call types: three produced by males (bark, guttural threat, and submissive call); five produced by females (bark, guttural threat, submissive call, growl, and pup attraction call) and the female attraction call produced by pups and yearlings. Vocalizations were compared according to age and sex classes. The overall structure and function of the pup attraction and female attraction call produced by females, yearlings, and pups, was similar. However, while similar in their overall appearance, certain call types have a lower fundamental frequency when compared with other fur seals. In addition, the male bark call alters in rate of production according to the context used, where calls are slower when males are stationary and advertising their territorial status and faster when males are involved in confrontations with other males or actively herding females. Further research is required to investigate changes in environmental conditions and their effects on shaping the call structure and communication in Australian fur seals.

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There has been increased focus on establishing landscape and sub-continental scale linkages and corridors in Australia in recent years. These include the WildCountry, Alps to Atherton, Naturelinks and Gondwana Link initiatives. However, there has been little discussion as to what the underlying tenure, land use and protection mechanisms might look like on the ground. The development of Biosphere Reserves and Conservation Management Networks (collectively ‘multi-tenure reserve networks’) which incorporate public and private conservation lands under a variety of tenures and protection mechanisms provides example of how this might be achieved.

Whilst the rhetoric has been strong the amount of actual research on what multi-tenure reserve networks mean in practice has been limited. This paper reflects on the lessons acquired from research into these networks and discusses with this practical insight the difference between rhetoric and performance in this vital area. In particular we discuss some of the ecological, social, governance and legal aspects of these networks. We will also proceed to hypothesise on what the future challenges are for multi-tenure reserve networks and what will be needed to overcome these challenges.

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The establishment of a comprehensive, adequate and representative (CAR) reserve system is not only an objective of all States and Territories but it is an international commitment, since Australia signed the Convention on Biological Diversity. Various reviews note that Australia lacks a representative freshwater reserve system. However, there has been surprisingly little quantitative analysis on the reservation of freshwater ecosystems from which to identify the gaps or deficiencies in the reserve system.

We compared aspects of reservation in wetlands in northern Victoria before and after a major public land use investigation by the government-appointed Victorian Environmental Assessment Council, which sought specifically to recommend a CAR reserve system. Significant improvements in the reservation status for depleted and under-reserved wetland ecosystems, and improved reserve design have been recommended by the investigation. Increases in the reservation of nationally and internationally significant wetlands were also recommended. These recommendations are now under consideration by the Victorian Government.

Some of the challenges in decision-making during this investigation and their implications on wetland conservation are highlighted. The paper concludes by outlining broader policy dilemmas, decisions and debates that that require addressing in relation to developing a system of Freshwater Protected Areas in Australia.

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In 2005, the Victorian government asked the Victorian Environmental Assessment Council (VEAC) to 1) identify and evaluate the extent, condition, values, management, resources and uses of riverine red gum forests and associated fauna, wetlands, floodplain ecosystems and vegetation communities in northern Victoria; and 2) make recommendations relating to the conservation, protection and ecological sustainable use of public land. The design of a comprehensive, adequate and representative (CAR) reserve system was a key part of the recommendations made by VEAC. In order to assist in the decision-making for environmental water allocation for protected areas and other public land, a process for identifying flood-dependent natural values on the Victorian floodplains of the River Murray and its tributaries was developed.

Although some areas such as the Barmah forest are very well known, there have been few comprehensive inventories of important natural values along the Murray floodplains. For this project, VEAC sought out and compiled data on flood requirements (natural flood frequency, critical interval between floods, minimum duration of floods) for all flood-dependent ecological vegetation classes (EVCs) and threatened species along the Goulburn, Ovens, King and Murray Rivers in Victoria. The project did not include the Kerang Lakes and floodplains of the Avoca, Loddon and Campaspe Rivers. 186 threatened species and 110 EVCs (covering 224,247 ha) were identified as flood-dependent and therefore at risk from insufficient flooding.

Past environmental water allocations have targeted a variety of different natural assets (e.g. stressed red gum trees, colonial nesting waterbirds, various fish species), but consideration of the water requirements of the full suite of floodplain ecosystems and significant species has been limited. By considering the water requirements of the full range of natural assets, the effectiveness of water delivery for biodiversity can be maximised. This approach highlights the species and ecosystems most in need of water and builds on the icon sites approach to view the Murray floodplains as an interconnected system. This project also identified for the first time the flood-frequency and duration requirements for the full suite of floodplain ecosystems and significant species.

This project is the most comprehensive identification of water requirements for natural values on the floodplain to date, and is able to be used immediately to guide prioritisation of environmental watering. As more information on floodplain EVCs and species becomes available, the water requirements and distribution of values can be refined by ecologists and land and water managers. That is, the project is intended as the start of an adaptive process allowing for the incorporation of monitoring and feedback over time. The project makes it possible to transparently and easily communicate the extent to which manipulated or natural flows benefit various natural values. Quantitative and visual outputs such as maps will enable environmental managers and the public to easily see which values do and do not receive water (see http://www.veac.vic.gov.au/riverredgumfinal.htm for further details).