Northwest Western Australia Research Articles

Comparison of alternative strategies for invasive species distribution modeling

Species distribution models (SDMs) can provide useful information for managing biological invasions, such as identification of priority areas for early detection or for determining containment boundaries. However, prediction of invasive species using SDMs can be challenging because they typically violate the core assumption of being at equilibrium with their environment, which may lead to poorly guided management resulting from high levels of omission. Our goal was to provide a suite of potential decision strategies (DSs) that were not reliant on the equilibrium assumption but rather could be chosen to better match the management application, which in this case was to ensure containment through adequate surveillance. We used presence-only data and expert knowledge for model calibration and presence/absence data to evaluate the potential distribution of an introduced mesquite (Leguminoseae: Prosopis) invasion located in the Pilbara Region of northwest Western Australia. Five different DSs with varying levels of conservatism/risk were derived from a multi-criteria evaluation model using ordered weighted averaging. The performance of DSs over all possible thresholds was examined using receiver operating characteristic (ROC) analysis. DSs not on the convex hull of the ROC curves were discarded. Two threshold determination methods (TDMs) were compared on the two remaining DSs, one that assumed equilibrium (by maximizing overall prediction success) and another that assumed the invasion was ongoing (using a 95% threshold for true positives). The most conservative DS fitted the validation data most closely but could only predict 75% of the presence data. A more risk-taking DS could predict 95% of the presence data, which identified 8.5 times more area for surveillance, and better highlighted known populations that are still rapidly invading. This DS and TDM coupling was considered to be the most appropriate for our management application. Our results show that predictive niche modeling was highly sensitive to risk levels, but that these can be tailored to match specified management objectives. The methods implemented can be readily adapted to other invasive species or for conservation purposes.

Localised and regional patterns in ground-dwelling beetle assemblages in a semi-tropical arid zone environment

– Ground-dwelling beetles were sampled by pitfall traps at 304 quadrats positioned to represent the geomorphic extent and profile of the Pilbara Region, a semi-tropical arid region in north-west Western Australia. For each quadrat, 47 climatic, soil, landform, geological and vegetation attributes were determined.

Sun-protective behaviours of beach goers in the North-West

The study investigates the sun-protective behaviours of beach goers in the north-west of Western Australia as the basis for a new health promotion intervention to be implemented in the area. A cross-sectional, observational survey of 1,498 beach goers in 25 beach locations across northwest Western Australia. Details of sun-protective clothing (none, hat with no shirt, shirt with no hat and full coverage) were recorded, as was time on beach, age and gender. Environmental audits were also completed to characterise the effects of the natural and built environments on sun-protective behaviours. Both females and children had the lowest rates of sun protection - 33.7% of females were found to wear shirts with no hats, compared to 29.0% of males, and they were less likely to be fully covered than males (30.3% compared to 41.5%). Children were more likely to wear shirts with no hats (43.1%) compared to adults (28.2%). Female and child beach goers represent two groups that are at a higher risk of developing skin cancer and, therefore, should become targets for a sustainable, effective and multi-component health promotion program.

Indigenous perceptions of contact at Inthanoona, Northwest Western Australia

AbstractInthanoona, a pastoral head station in the Pilbara region of Western Australia, which functioned from the 1860s to the 1890s includes an assemblage of more than 250 rock engravings of which 20% are identifiable contact period motifs. These include images of clothed men and women, guns, horses, sheep, wheeled vehicles, houses and ships. Spatial analysis of the structures, artefacts and engravings on the site supports the conclusion that the contact motifs demonstrate continuity in Indigenous modes of representation and innovation in subjects. They provide direct evidence of Aboriginal participation in, and perceptions of, the pastoral and pearl shell industries of the Pilbara.

Oxygen Isotope Compositions of Iron Oxides from High-Grade BIF-Hosted Iron Ore Deposits of the Central Hamersley Province, Western Australia: Constraints on the Evolution of Hydrothermal Fluids

The Hamersley province of northwest Western Australia is one of the world’s premier iron ore regions with high-grade martite-microplaty hematite iron ore deposits mostly hosted within banded iron formation (BIF) sequences of the Brockman Iron Formations of the Hamersley Group. These high-grade iron ores contain between 60 and 68 wt percent Fe, and formed by the multistage interaction of hydrothermal fluids with the host BIF formation. The oxygen isotope compositions of magnetite and hematite from BIF, hydrothermal alteration assemblages, and high-grade iron ore were analyzed from the Mount Tom Price, Paraburdoo, and Channar iron ore deposits. The δ18O values of magnetite and hematite from hydrothermal alteration assemblages and high-grade iron ore range from −9.0 to −2.9 per mil, a depletion of 5 to 15 per mil relative to the host BIF. The δ18O values are spatially controlled by faults within the deposits, a response to higher fluid flux and larger influence on the isotopic compositions by the hydrothermal fluids. The oxygen isotope composition of hydrothermal fluids (δ18Ofluid) indicates that the decrease in the 18O content of iron oxides was due to the interaction of both basinal brines and meteoric fluids with the original BIF. Late-stage talc-bearing ore at the Mount Tom Price deposit formed in the presence of a pulse of 18O-enriched basinal brine, indicating that hydrothermal fluids may have repeatedly interacted with the BIFs during the Paleoproterozoic.

Oxygen Isotope Compositions of Iron Oxides from High-Grade BIF-Hosted Iron Ore Deposits of the Central Hamersley Province, Western Australia: Constraints on the Evolution of Hydrothermal Fluids

The Hamersley province of northwest Western Australia is one of the world’s premier iron ore regions with high-grade martite-microplaty hematite iron ore deposits mostly hosted within banded iron formation (BIF) sequences of the Brockman Iron Formations of the Hamersley Group. These high-grade iron ores contain between 60 and 68 wt percent Fe, and formed by the multistage interaction of hydrothermal fluids with the host BIF formation. The oxygen isotope compositions of magnetite and hematite from BIF, hydrothermal alteration assemblages, and high-grade iron ore were analyzed from the Mount Tom Price, Paraburdoo, and Channar iron ore deposits. The δ18O values of magnetite and hematite from hydrothermal alteration assemblages and high-grade iron ore range from −9.0 to −2.9 per mil, a depletion of 5 to 15 per mil relative to the host BIF. The δ18O values are spatially controlled by faults within the deposits, a response to higher fluid flux and larger influence on the isotopic compositions by the hydrothermal fluids. The oxygen isotope composition of hydrothermal fluids (δ18Ofluid) indicates that the decrease in the 18O content of iron oxides was due to the interaction of both basinal brines and meteoric fluids with the original BIF. Late-stage talc-bearing ore at the Mount Tom Price deposit formed in the presence of a pulse of 18O-enriched basinal brine, indicating that hydrothermal fluids may have repeatedly interacted with the BIFs during the Paleoproterozoic.

Effect of muddy conditions in the field on the liveweight gain of cattle consuming Leucaena leucocephala - Digitaria eriantha pastures in north-west Australia

Cattle grazing leucaena (Leucaena leucocephala cv. Cunningham)–pangola grass (Digitaria eriantha cv. Steudel) pastures in the Ord River Irrigation Area in north-west Western Australia, sometimes exhibit higher liveweight gains in the dry season when temperature and humidity are lower. Two factors have been suggested as causing this seasonal difference: the combined effect of the temperature and humidity, and the effect of the muddy conditions in the field associated with rainfall in the wet summer season. An experiment over 81 days, from August to October 1995, was conducted to evaluate the effect of muddy conditions on the liveweight gain of cattle grazing a leucaena–pangola grass pasture. Replicated paddocks were grazed in a normal irrigated system during this dry season whereas other paddocks were flood irrigated twice weekly to create muddy conditions. Cattle grazing the muddy paddocks had a liveweight gain of 0.29 kg/steer.day, which was lower (P < 0.001) than the animals in the dry paddocks (0.57 kg/steer.day). These cattle spent less time grazing (41.9 v. 67.6% of animals grazing at three observation times, 0600, 1100 and 1500 hours, on each day over the whole 81 days; P ≤ 0.001). It was suggested that the muddy condition of the paddock was the primary factor causing this difference in liveweight gain and grazing behaviour.

Notes on crabs of the families Goneplacidae and Dorippidae (Decapoda: Brachyura) from the Dampier Archipelago, Western Australia

Nineteen specimens representing four species in the brachyuran f~milie.s Goneplacidae and Dorippidae were collected during a four year bIOlogIcal survey of the Dampier Archipelago, in northwest Western Australia, conducted by the Western Australia Museum. Two of the species are goneplacids, Eucrate affinis and E. dorsalis and the other two are dorippids, Dorippe quadridensand Paradorippeaustraliensis. Notes on range extensions, habitats, etc., are provided for these four species.

A rare East Indian Ocean autumn season tropical cut-off low: impacts and a high-resolution modelling study

There are two aims of this study. The first is to provide a synoptic description of the lifecycle and impacts of a seasonally rare but intense cut-off low of tropical origin that developed off the northwest coast of Australia, during the Southern Hemisphere autumn months of late April/early May, 2005. The second, and more important, part of this study is an assessment of the capacity of a state-of-the-science numerical model, assimilating all available satellite-derived observational data, to predict the track, intensity, duration, and severe weather that occurred during the life cycle of the cut-off low. The system was unusual in that its initial development occurred over tropical waters and was associated with a strong and highly involuted subtropical jetstream, generating a cloud band that produced record 24 h rainfall totals in northwest Western Australia for this time of the year. The cut-off low then underwent further deepening which produced more unseasonable heavy rainfall. Confirmed tornado reports occurred over the populous southwest corner of Western Australia.

The enigma of 3400 years BP coastal oolites in tropical northwest Western Australia… why then, why there?

Oolites crop out along the northwestern coast of Western Australia at Port Smith, about 80 km SW of Broome. An oolitic coastal ridge truncated by marine erosion exposes subtidal, intertidal, and supratidal (aeolian) facies. The deposits are firmly indurated and composed of about 75% tangentially and moderately thickly layered, aragonitic ooid grains with over 90% quartz nuclei. Subtidal sedimentary structures are exposed about a metre above the present high tide mark, hinting that sea level may have been somewhat higher when the shoreline was formed. However, the macrotidal range of up to 7 m, and the possibility of cyclonic surges along the coast, precludes unequivocal determinations on this point. Whole-rock amino acid racemisation (AAR) geochronology (epimerisation of isoleucine: d-alloisoleucine/ l-isoleucine or A/I) on each facies of the oolite outcrop averaged 0.106 ± 0.013 ( N = 10). The modern beach contains fewer ooids (∼ 30%), and nearly half of these are stained brown, grey, or black, perhaps as a result of burial, reduction and/or mineralization. A higher (older) mean and large standard deviation in whole-rock amino acid ratio of 0.145 ± 0.067 ( N = 2) supports our inference that ooids on the modern beach were reworked from fossil deposits. Reverse phase chronostratigraphy (RPC) on individual ooid grains holds tremendous promise in this preliminary study. RPC results show a narrow variation of d/ l values (CV = 6–11%), and yield nearly identical d/ l Asp means from light coloured fossil ooids (0.307 ± 0.018 ( N = 17)); light (0.323 ± 0.026 ( N = 12)) and dark coloured ooids (0.298 ± 0.027 ( N = 10)) from the active beach face. When compared to A/I ratios from 14C dated mid-Holocene ooids in the Bahamas, the mean A/I from Port Smith reflects an age of ca. 3500–4500 years that is in agreement with a calibrated AMS 14C age of 3370 ± 50 calendar years BP on the same material. Thus, the ooids were formed, transported, emplaced, strongly cemented, and largely eroded from the beach ridge in only 3400 years. The environmental conditions that underlie a pulse of ooid deposition during a brief period of the mid-Holocene almost certainly involve extensive tidal inlets in the area, a possible mid-Holocene oscillation 1–2 m above present, and a subsequent fall to present level that terminated the process. Apparently, a unique combination of factors produced ooids here, and in only a handful of other sites in Australia and the Indian Ocean.

Looking for Neanderthal Man, Finding a Captive White Woman: The Story of a Documentary Film

In 1928 the Australian racial psychologist Stanley David Porteus went to northwest Western Australia and central Australia to conduct psychological and psychophysical studies of sample Aboriginal groups. Porteus was accompanied by Paul Withington, a Honolulu surgeon and explorer, and two cinematographers. Withington, presenting the facade of a serious investigator searching for evidence of Neanderthal Man, told A.O. Neville, chief protector of Aborigines in Western Australia, that he was also making a film about Aboriginal life for educational purposes. After leaving Australia, Neville became increasingly concerned about this film. His queries to Porteus were met with uncertainty, and he received only silence from Withington. When the film was finally released, its representation of Aboriginal life was grossly distorted. This had far-reaching consequences for future researchers in Western Australia.

Marine benthic flora of the Dampier Archipelago, Western Australia

– There is a lack of information regarding the marine benthic flora of northwest Western Australia and a comprehensive flora for the region has never been produced. A checklist of the marine benthic flora of the Dampier Archipelago collected during the Western Australian Museum expeditions of 1998/1999 is presented.

Shell artefacts from northern Cape Range Peninsula, northwest Western Australia

This paper describes a range of flaked, ground and utilised shell artefacts that were recorded and analysed as part of a broader study of archaeological sites in a section of arid coastal northwest Western Australia. Despite the relative profusion of shell artefacts in the study area, ethnographic sources for the Cape Range region do not reference the making or using of shell artefacts by Aboriginal people. Previous and recent archaeological research in the Cape Range region are discussedand a shell artefact assemblage with components such as baler shell pendants, knives and dishes, shell beads and giant clam shell adzes is identified. Shell artefacts have been generally neglected by archaeologists in Australia, but are potentially a substantial source of information regarding the function of archaeological sites. This paper provides a resource for the identification of shell artefacts from sites in coastal northwestern Australia.

The diagnosis of chlamydia, gonorrhoea, and trichomonas infections by self obtained low vaginal swabs, in remote northern Australian clinical practice

Objective: To examine the diagnostic performance of self obtained low vaginal swabs (SOLVS) and polymerase chain reaction (PCR) techniques in the diagnosis of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and...

Prionospio thalanji sp. nov. (Polychaeta: Spionidae) from an anchialine cave, Cape Range, north-west Western Australia

Prionospio thalanji sp. nov. (Polychaeta: Spionidae) from an anchialine cave, Cape Range, north-west Western Australia

Effectiveness of a community-directed ‘healthy lifestyle’ program in a remote Australian Aboriginal community

ObjectiveTo assess the sustainability and effectiveness of a community-directed program for primary and secondary prevention of obesity, diabetes and cardiovascular disease in an Aboriginal community in north-west Western Australia. MethodEvaluation of health outcomes (body mass index, glucose tolerance, and plasma insulin and triglyceride concentrations) in a cohort of high-risk individuals (n=49, followed over two years) and cross-sectional community samples (n=200 at baseline, 185 at two-year and 132 at four-year follow-ups), process (interventions and their implementation) and impact (diet and exercise behaviour). ResultsFor the high-risk cohort, involvement in diet and/or exercise strategies was associated with protection from increases in plasma glucose and triglycerides seen in a comparison group; however, sustained weight loss was not achieved. At the community level, significant reductions were observed in fasting insulin concentration but no change in prevalence of diabetes, overweight or obesity. Weight gain remained a problem among younger people. Sustainable improvements were observed for dietary intake and level of physical activity. These changes were related to supportive policies implemented by the community council and store management. ConclusionsCommunity control and ownership enabled embedding and sustainability of program, in association with social environmental policy changes and long-term improvements in important risk factors for chronic disease. ImplicationsDevelopmental initiatives facilitating planning, implementation and ownership of interventions by community members and organisations can be a feasible and effective way to achieve sustainable improvements in health behaviours and selected health outcomes among Aboriginal people.

Comparative erythrocyte metabolism in three species of marsupials from Western Australia

A comparative study was carried out to investigate various aspects of erythrocyte metabolism in three species of marsupials located in the western part of Australia. The burrowing bettong (Bettongia lesueur) and the Barrow Island euro (Macropus robustus isabellinus) were captured on Barrow Island whereas the mainland euro (Macropus robustus erubescens) was captured from the Pilbara region of northwest Western Australia. Aspects of erythrocyte metabolism studied included: levels of glycolytic intermediates, enzyme activities, sensitivity of erythrocytes to oxidants and methaemoglobin reducing capacity. Some important findings were: (1) no relationship was observed between haemoglobin and diphosphoglycerate levels; (2) both species from Barrow Island had lower levels of catalase than the mainland species; and (3) methaemoglobin reductive capacity was greater in the erythrocytes of the burrowing bettong compared to the two species of euro.

Effect of maize supplementation, seasonal temperature and humidity on the liveweight gain of steers grazing irrigated Leucaena leucocephala/Digitaria eriantha pastures in north-west Australia

Brahman Shorthorn steers (213±4·6 kg initial weight) were grazed on a pangola (Digitaria eriantha cv. Steudel) pasture interplanted with leucaena (Leucaena leucocephala cv. Cunningham) in rows 1·8–2·7 m apart in the Ord River Irrigation Area (ORIA) in north-west Western Australia. The leucaena comprised a mean of 46% of the diet but ranged from 100% of the diet on day 1 to c. 18% on day 7 of a 7-day grazing period, within the rotational grazing system. It was suggested that the low herbage allowance of leucaena may have restricted the intake of the steers, reducing the quantity and quality of the herbage consumed.The steers were also supplemented with maize during the dry and wet seasons (1992 and 1992/93). The maize supplement was offered at 0, 0·5, 1·0, 1·5 and 2·0 kg/head per day, over a 168-day period. Maize supplementation at 1·5 kg maize per head per day resulted in an increase in the liveweight gain of the steers grazing leucaena/pangola pastures in the dry season from 0·73±0·05 kg/day (mean±S.E.) for no supplementation to 1·1±0·05 kg/day for 1·5 kg/head per day of maize. Maize supplementation up to 2·0 kg/day did not further increase the liveweight gain. A high rate of substitution of leucaena and pangola intake for the maize supplement occurred.There was a large seasonal difference in liveweight gain (mean 0·89 v. 0·63 kg/day for the dry and wet seasons respectively; P<0·001) irrespective of the level of maize supplementation. This seasonal difference in liveweight gain was not primarily a function of the herbage on offer, but was most probably a direct function of the effect of the seasonal temperature and humidity influencing the feed intake and growth rate of these Brahman crossbred cattle.This system produced some of the higher liveweight gains recorded per hectare for a grazing system (1570–2110 kg/ha per year), as a result of the very good individual liveweight gains (250-340 kg/head per year) and high stocking rate (6·25 head/ha).

‘Mr Neville did all in [his] power to assist me’: A. P. Elkin, A. O. Neville and Anthropological Research in Northwest Western Australia, 1927–1928

ABSTRACTFrom the commencement of his field research A. P. Elkin sought to bring a practical application to his work on Aborigines. He positioned anthropology as an enabling science which had the capacity to reduce conflict, violence and misunderstanding on the frontier. He stated that the ‘object of his mission [field work]’ was both ‘academic and practical’. He declared that the knowledge gained through anthropological field research would serve not only narrow academic aims but would also be put at the service of government. Anthropology's purpose was to inform and influence the formulation of government Aboriginal policy. This paper examines Elkin's first encounter and interaction with government through his relationship with A. O. Neville, chief protector of Aborigines in Western Australia. It illustrates the beginnings of what Gillian Cowlishaw has called a discourse of helping, that is Australian anthropologists in the 1930s constructed a discourse about their usefulness to government. It was a discourse which seemingly lacked critical distance from the policies of government. I argue that this discourse of helping government was heavily influenced by Elkin once he became professor of anthropology but it can be discovered in this earlier period. I conclude by discussing how the implications of this discourse were played out in the decade of the 1930s. The focus of this paper is on Elkin and his relationship with Neville and the consequences of this relationship for Elkin's later actions.

‘The natives are happy’: A.P. Elkin, A.O. Neville and anthropological research in Northwest Western Australia

‘The natives are happy’: A.P. Elkin, A.O. Neville and anthropological research in Northwest Western Australia