667 research outputs found
James Butchart, Glenisla, to father
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/267910Description of the property and his job; cultivation on neighbouring land; description of a trip with Coghill to the Murray River looking for a run; running cattle relates being followed by group of Aboriginals; again urges his father to migrate; wages, prospects. Note: 'January 1847' is written at the top in pencil, but the letter was evidently commenced in about August 1846, and resumed on 13 December 1846, the latter date appearing at the top of page 2
PLACE NAMES: Gariwerd / Grampians (W Vic SJ54-03, SJ54-07, SJ54-08)
PLACE NAMES: Victoria Range (Gariwerd / Grampians W Vic SJ54-07)
PLACE NAMES: Glenelg River (W Vic SJ54-07, SJ54-08)
PLACE NAMES: Murray Bridge (SE SA SI54-13)
PLACE NAMES: River Murray (SW NSW, N Vic, SE SA SI54, SI55)
KEYWORDS: Koori, Aboriginal, Indigenous105273
Item: [1990.0083.00021] "James Butchart, Glenisla, to father
An Investigation into the performance and representations of a Stochastic Evolutionary Neural Tree
No full textAbstract: The Stochastic Competitive Evolutionary Neural Tree (SCENT) is a new unsupervised neural net that dynamically evolves a representational structure in response to its training data. Uniquely SCENT requires no initial parameter setting as it autonomously creates appropriate parameterisation at runtime. Pruning and convergence are stochastically controlled using locally calculated heuristics. A thorough investigation into the performance of SCENT is presented. The network is compared to other dynamic tree based models and to a high quality flat clusterer over a variety of data sets and runs. In this paper we report a thorough comparative analysis of the performance of a new unsupervised neural net architecture, SCENT, first introduced in [Butchart et al., 1996b]. This architecture contains two unique features: firstly in its combination of evolutionary growth with stochastic pruning and secondly in its dynamic, autonomous parameterisation; the user supplies no information to the net aside from the training data. Here w
Footprints on the Sands of Time: Retracing Harvey Butchart's Exploration of the Grand Canyon through His Annotated Matthes-Evans Maps – Video Recording
No full textabstract: John Harvey Butchart was a mathematics professor at Northern Arizona University from 1945 to 1973. From 1945 to 1987, he spent considerable time in the Grand Canyon, hiking established trails, exploring obscure routes, and discovering new routes. In all, Dr. Butchart spent over 1,000 days in the Grand Canyon and traveled over 12,000 miles in the Canyon. Dr. Butchart kept journals on his explorations and complemented those notes with a heavily annotated copy of the 1927 Francois Matthes and Richard Evans East Half, West Half topographic maps of the Grand Canyon. Embedded in Butchart’s annotated Matthes-Evans maps are compelling stories of adventure, discovery, triumph, and heartbreak. This presentation will highlight selections of those stories and the impact this map has had on subsequent hiking exploration in the Canyon
Improved predictability of the troposphere using stratospheric final warmings
No full textThe final warming of the stratospheric polar vortex at the end of northern hemisphere winter is examined in ECMWF ERA-Interim reanalysis data and an ensemble of chemistry climate models, using 20 years of data from each. In some years the final warming is found to occur first in the mid-stratosphere, and in others to occur first in the upper stratosphere. The strength of the winter stratospheric polar vortex, refraction of planetary waves, and the altitudes at which the planetary waves break in the northern extratropics lead to this difference in the vertical profile of the final warming. Years in which the final warming occurs first in the mid-stratosphere show, on average, a more negative NAO pattern in April mean sea level pressure than years in which the warming occurs first in the upper stratosphere. Thus, in the northern hemisphere, additional predictive skill of tropospheric climate in April can be gained from a knowledge of the vertical profile of the stratospheric final warming
Nautical Chic exhibition
No full textAmber Butchart's book Nautical Chic was the subject of an exhibition at the Fashion and Textile Museum, in conjunction with their ‘Riviera Style’ show running from May – August 2015. The display featured spreads from the book as well as garments and ephemera curated by the author to illustrate the timeless appeal of maritime style
Impact of alternative metrics on estimates of extent of occurrence for extinction risk assessment
No full textIn International Union for Conservation of Nature (IUCN) Red List assessments, extent of occurrence (EOO) is a key measure of extinction risk. However, the way assessors estimate EOO from maps of species’ distributions is inconsistent among assessments of different species and among major taxonomic groups. Assessors often estimate EOO from the area of mapped distribution, but these maps often exclude areas that are not habitat in idiosyncratic ways and are not created at the same spatial resolutions. We assessed the impact on extinction risk categories of applying different methods (minimum convex polygon, alpha hull) for estimating EOO for 21,763 species of mammals, birds, and amphibians. Overall, the percentage of threatened species requiring down listing to a lower category of threat (taking into account other Red List criteria under which they qualified) spanned 11–13% for all species combined (14–15% for mammals, 7–8% for birds, and 12–15% for amphibians). These down listings resulted from larger estimates of EOO and depended on the EOO calculation method. Using birds as an example, we found that 14% of threatened and near threatened species could require down listing based on the minimum convex polygon (MCP) approach, an approach that is now recommended by IUCN. Other metrics (such as alpha hull) had marginally smaller impacts. Our results suggest that uniformly applying the MCP approach may lead to a one-time down listing of hundreds of species but ultimately ensure consistency across assessments and realign the calculation of EOO with the theoretical basis on which the metric was founded
Trends and patterns in the extinction risk of Australia's birds over three decades
No full textAustralia recently committed through the Kunming-Montreal Global Biodiversity Framework (GBF) to halt human-induced extinction of known threatened species and to reduce extinction risk of threatened species significantly by 2030. We review recent trends in extinction risk of Australian birds to provide context for current and future conservation efforts. We calculate the Red List Index (RLI) for all Australian birds as well as subsets based on geography, habitat and taxonomy. Over the period 2010 to 2020, the number of taxa reassigned to lower categories of extinction risk (n = 20; 1.5% of all taxa included) was greatly outweighed by the number moved to higher categories owing to deteriorating status (n = 93; 7%). This resulted in the steepest decadal decline in the RLI since data were first compiled in 1990. It was chiefly driven by rapid population declines in migratory shorebirds, loss of suitable habitat for species affected by wildfire in 2019–2020 and, to a lesser extent, declines in the abundance of upland rainforest birds. To a small extent, these losses were counterbalanced by improvements in status of some bird species resulting from local eradication of invasive mammals, primarily from Macquarie Island. For Australia to meet the commitments recently adopted through the GBF, conservation interventions (and hence funding) will need to be scaled up substantially. The RLI is well placed for monitoring progress towards the GBF targets and for communicating trends in the extinction risk to national avifaunas.Alex J. Berryman, Stuart H. M. Butchart, Micha V. Jackson, Sarah M. Legge, George Olah, Janelle Thomas, John C. Z. Woinarski and Stephen T. Garnet
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