scholarly journals Oceanographic influence on coastal zooplankton assemblages at three IMOS National Reference Stations in Western Australia

2020 ◽  
Vol 71 (12) ◽  
pp. 1672
Author(s):  
Erin McCosker ◽  
Claire H. Davies ◽  
Lynnath E. Beckley
Keyword(s):  
Western Australia ◽  
Detailed Comparison ◽  
Latitudinal Gradients ◽  
Zooplankton Abundance ◽  
Spatial And Temporal Patterns ◽  
North West ◽  
Leeuwin Current ◽  
National Reference ◽  
The North ◽  
E 32

Knowledge about the coastal zooplankton of the south-eastern Indian Ocean is limited, with few studies having compared assemblages across the latitudinal range of the western seaboard of Australia. The dominant oceanographic feature in this region is the Leeuwin Current, which transports warm, lower-salinity, tropical waters southward along the shelf-edge. This study examined data collected by Australia’s Integrated Marine Observing System at three coastal National Reference Stations located at 22°S 114°E, 32°S 115°E and 34°S 122°E. Spatial and temporal patterns in zooplankton abundance, composition and diversity were investigated, and differences in assemblage structure, particularly with respect to copepods, were related to oceanographic conditions. Clear dissimilarities among copepod assemblages were observed, becoming weaker in winter owing to enhanced connectivity of species driven by alongshore and cross-shelf transport in the Leeuwin Current. Both physical and biogeochemical factors were significant in structuring copepod assemblages, with seawater density, incorporating temperature and salinity, exerting the greatest influence. The results suggest that both broad-scale latitudinal gradients and mesoscale events contribute to variation in zooplankton assemblages in these waters. This study provides the first detailed comparison of zooplankton assemblages among the north-west, south-west and southern coastal waters of Western Australia, and enhances understanding of the processes influencing zooplankton distribution and structure.

Spatial and temporal patterns of reptile roadkill in the north-west Australian tropics

2019 ◽  
Vol 25 (4) ◽  
pp. 370 ◽  
Author(s):  
Holly Hastings ◽  
James Barr ◽  
Philip W. Bateman
Keyword(s):  
Western Australia ◽  
High Rate ◽  
Survey Method ◽  
Road Mortality ◽  
Natural Ecosystems ◽  
Spatial And Temporal Patterns ◽  
Wet Season ◽  
North West ◽  
The North ◽  
Carcass Persistence

Roads present unavoidable challenges to wildlife, both in populated and in more remote regions. Both traffic infrastructure and road vehicles can have a detrimental impact on natural ecosystems and wildlife populations. This study aimed to gain a broad overview of the impacts of a stretch of road on native herpetofauna in north-western Australia. Reptile roadkill was surveyed along a 31-km stretch of the main road in Broome, Western Australia for eight months, during both the wet and dry seasons. There was a significantly higher rate of road mortality in the wet season despite a decrease in traffic intensity. Incidence of roadkill varied between reptile clades, with varanids being the mostly frequently recorded as roadkill. Carcass persistence experiments, however, highlighted a potential significant underestimation in roadkill due to an extremely high rate of carcass removal, emphasising the need to consider this variable when using roadkill as a survey method. We recommend that carcass persistence should be further investigated in order to accurately assess extent of reptile roadkill in the region, and how roads and traffic may impact at-risk species and populations.

Community Dynamics and Metabolic Potential of Petroleum-Degrading Microbes in the North West Shelf, Western Australia

2019 ◽  
Author(s):  
Darren Cheah ◽  
Kliti Grice ◽  
Cornelia Wuchter ◽  
Alan G. Scarlett ◽  
Marco J. L. Coolen
Keyword(s):  
Western Australia ◽  
Community Dynamics ◽  
Metabolic Potential ◽  
North West ◽  
The North

Dynamics of the Ningaloo Current off Point Cloates, Western Australia

2006 ◽  
Vol 57 (3) ◽  
pp. 291 ◽  
Author(s):  
Mun Woo ◽  
Charitha Pattiaratchi ◽  
William Schroeder
Keyword(s):  
Numerical Model ◽  
Continental Shelf ◽  
Western Australia ◽  
Bottom Topography ◽  
Volume Transport ◽  
Relative Strength ◽  
Cross Sectional ◽  
Leeuwin Current ◽  
The North ◽  
Tropical Water

The Ningaloo Current (NC) is a wind-driven, northward-flowing current present during the summer months along the continental shelf between the latitudes of 22° and 24°S off the coastline of Western Australia. The southward flowing Leeuwin Current is located further offshore and flows along the continental shelf break and slope, transporting warm, relatively fresh, tropical water poleward. A recurrent feature, frequently observed in satellite images (both thermal and ocean colour), is an anti-clockwise circulation located offshore Point Cloates. Here, the seaward extension of the coastal promontory blocks off the broad, gradual southern shelf, leaving only a narrow, extremely steep shelf to the north. The reduction in the cross-sectional area, from the coast to the 50 m contour, between southward and northward of the promontory is ~80%. Here, a numerical model study is undertaken to simulate processes leading to the development of the recirculation feature offshore Point Cloates. The numerical model output reproduced the recirculation feature and indicated that a combination of southerly winds, and coastal and bottom topography, off Point Cloates is responsible for the recirculation. The results also demonstrated that stronger southerly winds generated a higher volume transport in the NC and that the recirculation feature was dependent on the wind speed, with stronger winds decreasing the relative strength of the recirculation.

TWO AND THREE DIMENSIONAL ANALOGUE MODELLING OF EXTENSIONAL FAULT SYSTEMS WITH APPLICATION TO THE NORTH WEST SHELF, WESTERN AUSTRALIA.

1994 ◽  
Vol 34 (1) ◽  
pp. 555
Author(s):  
N. M. Lemon ◽  
T. Mahmood
Keyword(s):  
Western Australia ◽  
Three Dimensional ◽  
Sedimentary Sequence ◽  
Progressive Deformation ◽  
Plan View ◽  
North West ◽  
The North ◽  
Analogue Modelling ◽  
Extensional Structures ◽  
Geometry And Kinematics

The North West Shelf of Western Australia is an area of known extensional control with a number of inbuilt complexities related to variations in direction of extension and the existence of early fracture sets. Analogue modelling in a sandbox of modest construction and proportions can imitate the style of structures imaged by seismic on the North West Shelf. Models were constructed to simulate deformation in a sedimentary sequence above simple listric, ramp/flat and complex 3D detachment surfaces. A new 3D technique has been devised to simulate progressive deformation above complex detachment morphologies. Analysis of the structures produced has been achieved by marrying sequential plan view photographs of the model surface with serial vertical sections of the bulk of the model once the experiment has been completed and the sand stabilised. This technique also has the ability to simulate geometry and kinematics of extensional structures in a complex polyphase area. This 3D technique has proven particularly useful in the understanding of structures developed in regions where the sedimentary sequence has been subject to more than one period of extension, each with different orientations. The models provide the first understanding of the areal distribution of fault patterns and associated subsidiary troughs in areas of complex detachments. These models show the distribution of pre-rift and syn-rift sediments in extensional terranes and are valuable in the prediction of deformation in areas of poor seismic quality and for confirmation of seismic interpretation.

Extensional fault-related folding of the North West shelf, Western Australia

AAPG Bulletin ◽  
2020 ◽  
Vol 104 (4) ◽  
pp. 913-938
Author(s):  
Sam McHarg ◽  
Chris Elders ◽  
Jane Cunneen
Keyword(s):  
Western Australia ◽  
North West ◽  
The North

Community structure and zoogeographic affinities of the coastal fishes of the Dampier region of north-western Australia.

1985 ◽  
Vol 36 (2) ◽  
pp. 247 ◽  
Author(s):  
SJM Blaber ◽  
JW Young ◽  
MC Dunning
Keyword(s):  
Community Structure ◽  
Western Australia ◽  
High Tide ◽  
Organic Content ◽  
Tidal Range ◽  
Nursery Ground ◽  
North West ◽  
Physical Conditions ◽  
The North ◽  
North Western

The species composition and broad trophic structure of the mangrove creek and open shore fish communities of the Dampier region in tropical north-western Australia are described. The habitats are characterized by a lack of freshwater influence, low turbidity and a tidal range in excess of 4 m. Both mangroves and open shores have a diversity of species typical of Indo-west Pacific coastal waters but the physical conditions have modified the community structure both to exclude many families that prefer areas of higher turbidity and reduced salinity, and to include others that usually occur only in clear waters. The fish faunas of the mangroves (113 species) and open shores (106 species) are compared: 54 species were common to both. The deeper waters were dominated by piscivores, which penetrated throughout the mangroves at high tide. Iliophagous species were abundant, particularly in the mangroves where the organic content of the substratum (7.8-8.2%) was not reduced markedly compared with other areas of the Indo-Pacific, despite the lack of freshwater inflow. The clear and deep water in the mangroves at high tide favour predation on juveniles by piscivorous fishes and reduce the effectiveness of such areas as nurseries. There is virtually no overlap of the fauna with that of the deeper waters (>20 m) of the North West Shelf, and the inshore region is not a significant nursery ground for any of the commercially important deeper water species.

Pidgin Ngarluma

1998 ◽  
Vol 13 (1) ◽  
pp. 1-61 ◽  
Author(s):  
Alan Dench
Keyword(s):  
Western Australia ◽  
West Coast ◽  
Aboriginal People ◽  
North West ◽  
The North ◽  
Australian Languages

This paper discusses evidence of an early pidgin in use amongst Aboriginal people of the north west coast of Western Australia. The crucial evidence comes from an Italian manuscript describing the rescue, by local Aborigines, of two castaways wrecked on North West Cape in 1875. The data reveals that the local Aborigines attempted to communicate with the Italian-speaking survivors using what appears to be an Australian language spoken some 300 kilometers further along the coast, around the emerging center of the new Pilbara pearling industry. I present an analysis of the material, showing that it differs from Australian languages of the area in significant ways and can be considered a reduced variety. I conclude that this variety is an indigenous pidgin — the first to be described for Australia.

scholarly journals Eurasian Hobby Falco subbuteo: A review of recent records from Western Australia and Australian external territories

2021 ◽  
Vol 38 ◽  
pp. 119-123
Author(s):  
Marcus Singor
Keyword(s):  
Western Australia ◽  
Coastal Plain ◽  
Austral Summer ◽  
North West ◽  
The North ◽  
Swan Coastal Plain

All Australian records of the Eurasian Hobby Falco subbuteo are summarised. Before 2016, the only Australian records of the Eurasian Hobby were on external territories to the north-west of the mainland. Each year between 2016 and 2021 a single Eurasian Hobby was observed as an austral summer visitor to the Swan Coastal Plain in south-western Western Australia. These sightings involved an adult in 2016, 2019 and 2020, and single immature birds in 2017–2018. The age of the Hobby seen in 2020–2021 was undetermined. As it appears that multiple individuals have been recorded across years, it is likely that the species is now more than just an accidental vagrant to Australia.

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