Zeitschriftenartikel: „Coastal biology – Western Australia – South-West“

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SHATTUCK, STEVEN O. „Austromorium, a new myrmicine ant genus from Australia (Hymenoptera: Formicidae)“. Zootaxa 2193, Nr. 1 (10.08.2009): 62–68. http://dx.doi.org/10.11646/zootaxa.2193.1.3.

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The myrmicine ant genus Austromorium is described for two Australian endemic species. One species has been known for some time but its taxonomic placement has been unclear while the second species is newly described. They are thought to be related to Lordomyrma and Austromorium is tentatively placed within the tribe Stenammini. These are ground-nesting ants although little else is known of their biology. While one species is widespread across semi-arid southern Australia the other is restricted to a narrow band of coastal south-western Western Australia.

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Slater, James A., Randall T. Schuh, Gerasimos Cassis, Christine A. Johnson und Paola Pedraza-Peñalosa. „Revision of Laryngodus Herrich-Schaeffer, an Allocasuarina feeder, with comments on its biology and the classification of the family (Heteroptera:Lygaeoidea:Rhyparochromidae)“. Invertebrate Systematics 23, Nr. 2 (2009): 111. http://dx.doi.org/10.1071/is08028.

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Laryngodus Herrich-Schaeffer, 1850, is redescribed, including, for the first time, nymphal morphology. Three species are recognised based on qualitative morphology, a principle components analysis of morphometric data, and the study of sequence data from the mitochondrial genes COI and 16S. They are: L. australiae Herrich-Schaeffer from the south-western coastal area of Western Australia, L. cervantes, sp. nov., from southern Western Australia, and L. luteomaculatus, sp. nov., from western Victoria and adjacent South Australia. Sexual dimorphism in all species and variation in males of L. luteomaculatus, sp. nov. is documented and discussed. All species and their hosts are illustrated with colour digital images; scanning electron micrographs are used to illustrate male prosternal spines, antennnae, abdominal trichobothria, and other structures. Male genitalic morphology is illustrated with line drawings. Authoritative host identifications indicate that Laryngodus is restricted to feeding on several species of Allocasuarina (Casuarinaceae); nymphs and adults are known to live on the plants and to be strongly associated with the cone-like fruits. The tribal placement of Laryngodus is discussed.

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Hughes, Julian M., John Stewart, Benjamin W. Kendall und Charles A. Gray. „Growth and reproductive biology of tarwhine Rhabdosargus sarba (Sparidae) in eastern Australia“. Marine and Freshwater Research 59, Nr. 12 (2008): 1111. http://dx.doi.org/10.1071/mf08102.

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The growth and reproductive biology of the commercially and recreationally important sparid fish, tarwhine (Rhabdosargus sarba), was examined from the coastal waters of New South Wales (NSW), south-eastern Australia. Previous research on this species in other parts of the world has yielded conflicting results concerning its growth and reproductive biology. Age estimates were made by counting opaque zones in otolith sections. The method was validated by marking the otoliths of captive fish with alizarin complexone, and also by marginal increment analyses using otoliths from wild-caught fish. Both sexes grew at a similar rate. Von Bertalanffy growth function parameters were: L∞ = 26.40 ± 0.40 cm fork length (FL), k = 0.39 ± 0.02 year–1 and to = –0.56 ± 0.09 years. The maximum estimated age was 16.5 years. Spawning occurred from May to August with a peak in July. Both sexes matured at a similar size (L50 = 19.44 ± 0.15 cm FL), which was larger than the current minimum legal length in NSW. Ovotestes were identified in adult tarwhine and were confirmed by histological analyses. Results of this study provided evidence that tarwhine are likely to be rudimentary hermaphrodites in eastern Australia and are more similar in growth rate, maximum size/age, and reproductive biology to tarwhine from Western Australia than those from other parts of the world.

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Honan, JA, und BD Mitchell. „Reproduction of Euastacus bispinosus Clark (Decapoda:Parastacidae), and trends in the reproductive characteristics of freshwater crayfish“. Marine and Freshwater Research 46, Nr. 2 (1995): 485. http://dx.doi.org/10.1071/mf9950485.

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The reproductive biology of Euastacus bispinosus populations was studied in a river and a creek of the Glenelg River system in south-western Victoria, and a small coastal creek in south-eastern South Australia. Females produced eggs in the first breeding season after maturation of their gonopores. At the Victorian sites, E. bispinosus spawned in early May, carrying eggs for about seven months before hatching and juvenile release in October-December. At least 95% of mature females at each Victorian site carried eggs during the breeding season. Mature females had relatively broader abdomens than did males and carried between 63 and 812 eggs. The number of eggs carried was linearly related to both occipital carapace length and abdomen width. The South Australian population differed from the Victorian populations in having a smaller mean size at sexual maturity for females (occipital carapace length 58 mm compared with 85-86 mm in Victoria), a higher proportion (17%) of gonopore abnormalities (< 1% in Victoria), and relatively wider abdomens (which continued to broaden after maturity). Euastacus bispinosus is a winter brooder and has a long generation time and low potential reproductive rate, characteristics it shares with Astacopsis and Parastacoides species, and members of the Astacidae. Other crayfish species (e.g. Cherax species and members of the Cambaridae) are summer brooders and tend to have a high potential reproductive rate and short generation time.

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Just, Michael P., David J. Merritt, Shane R. Turner, John G. Conran und Adam T. Cross. „Seed germination biology of the Albany pitcher plant, Cephalotus follicularis“. Australian Journal of Botany 67, Nr. 7 (2019): 480. http://dx.doi.org/10.1071/bt19053.

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Cephalotus follicularis is an ecologically unique, taxonomically isolated and range-restricted carnivorous plant that occurs exclusively within vulnerable wetland habitats in coastal south-western Australia. Very little is known about the reproductive biology of this iconic plant species, particularly in relation to seed dormancy and the specific requirements for germination. This knowledge gap must be filled to facilitate the establishment of conservation and management initiatives for the species, as Cephalotus is increasingly impacted by habitat loss, alteration to natural hydrological and fire regimes and, in recent times, climatic change. This study aimed to determine the type of seed dormancy that the seeds of Cephalotus possess, determine the optimum conditions required for seed germination, and examine the storage behaviour of seeds. The seeds of Cephalotus are small (1.0 × 0.5 mm), lightweight (0.1 mg) and remain indehiscent within a wind-dispersed hairy achene. Results suggest that the seeds may exhibit some sensitivity to desiccation and appear to be short lived (<12 months) when stored at 23°C. Maximum germination was achieved after 16 weeks incubation at 15°C for seeds removed from the protective outer layer of the achene, while seeds retained within the protective outer layer displayed lower germination success. The post-ripening morphological changes in the embryo, limited response to gibberellic acid, and the long time period required for germination suggests that the seeds exhibit morphophysiological dormancy, with a fraction of seeds remaining dormant for a period of time post-dispersal. These results highlight the importance of limiting hydrological alteration within the few remaining habitats that continue to support Cephalotus, but to ensure its long-term protection, further research focusing on phenology and in situ recruitment is required.

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Kealley, Luke, Paul Doughty, Mitzy Pepper, J. Scott Keogh, Mia Hillyer und Joel Huey. „Conspicuously concealed: revision of the arid clade of theGehyra variegata(Gekkonidae) group in Western Australia using an integrative molecular and morphological approach, with the description of five cryptic species“. PeerJ 6 (19.07.2018): e5334. http://dx.doi.org/10.7717/peerj.5334.

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The methods used to detect and describe morphologically cryptic species have advanced in recent years, owing to the integrative nature of molecular and morphological techniques required to elucidate them. Here we integrate recent phylogenomic work that sequenced many genes but few individuals, with new data from mtDNA and morphology from hundreds of gecko specimens of theGehyra variegatagroup from the Australian arid zone. To better understand morphological and geographical boundaries among cryptic forms, we generated new sequences from 656Gehyraindividuals, largely assigned toG. variegatagroup members over a wide area in Western Australia, with especially dense sampling in the Pilbara region, and combined them with 566Gehyrasequences from GenBank, resulting in a dataset of 1,222 specimens. Results indicated the existence of several cryptic species, from new species with diagnostic morphological characters, to cases when there were no useful characters to discriminate among genetically distinctive species. In addition, the cryptic species often showed counter-intuitive distributions, including broad sympatry among some forms and short range endemism in other cases. Two new species were on long branches in the phylogram and restricted to the northern Pilbara region: most records of the moderately sizedG. incognitasp. nov. are near the coast with isolated inland records, whereas the small-bodied saxicolineG. unguiculatasp. nov. is only known from a small area in the extreme north of the Pilbara. Three new species were on shorter branches in the phylogram and allied toG. montium. The moderately sizedG. cryptasp. nov. occurs in the western and southern Pilbara and extends south through the Murchison region; this species was distinctive genetically, but with wide overlap of characters with its sister species,G. montium. Accordingly, we provide a table of diagnostic nucleotides for this species as well as for all other species treated here. Two small-bodied species occur in isolated coastal regions:G. capensissp. nov. is restricted to the North West Cape andG. ocellatasp. nov. occurs on Barrow Island and other neighbouring islands. The latter species showed evidence of introgression with the mtDNA ofG. cryptasp. nov., possibly due to recent connectivity with the mainland owing to fluctuating sea levels. However,G. ocellatasp. nov. was more closely related toG. capensissp. nov. in the phylogenomic data and in morphology. Our study illustrates the benefits of combining phylogenomic data with extensive screens of mtDNA to identify large numbers of individuals to the correct cryptic species. This approach was able to provide sufficient samples with which to assess morphological variation. Furthermore, determination of geographic distributions of the new cryptic species should greatly assist with identification in the field, demonstrating the utility of sampling large numbers of specimens across wide areas.

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Fairclough, D. V., W. F. Dimmlich und I. C. Potter. „Reproductive biology of the Australian herring Arripis georgiana“. Marine and Freshwater Research 51, Nr. 6 (2000): 619. http://dx.doi.org/10.1071/mf99119.

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Arripis georgiana was collected from along the Western Australian and South Australian coasts at regular intervals between October 1996 and December 1998. The trends exhibited during the year by gonadosomatic indices, gonadal maturity stages and oocyte stages demonstrate that spawning is restricted to south-western Australian waters from at least as far north as ~28˚43′S to as far east as ~119˚24′E, and that it occurs mainly during late May and early June. The simultaneous presence of post-ovulatory follicles and hydrated and yolk-granule oocytes in some ovaries during the spawning period indicates that A. georgiana is a multiple spawner, i.e. females spawn more than once in a breeding season. In south-western Australia, where all life-cycle stages are found, the overall sex ratio in catches collected by netting was close to parity, whereas females predominated in those obtained by anglers. The length at which 50% of fish reached maturity was 197 mm for females and 179 mm for males, and just over 50% of females and ~80% of males attained maturity at the end of their second year of life. The implications of these data for management of the fishery for A. georgiana are discussed.

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Forbes, Matt, Ryan Vogwill und Kimberly Onton. „A characterisation of the coastal tufa deposits of south–west Western Australia“. Sedimentary Geology 232, Nr. 1-2 (Dezember 2010): 52–65. http://dx.doi.org/10.1016/j.sedgeo.2010.09.009.

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Oram, Rex, und Greg Lodge. „Trends in temperate Australian grass breeding and selection“. Australian Journal of Agricultural Research 54, Nr. 3 (2003): 211. http://dx.doi.org/10.1071/ar02137.

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Current trends in grass cultivar development are reviewed, with respect to the range of species involved, and the objectives and methodology within each species. Extrapolations and predictions are made about future directions and methodologies. It is assumed that selection will necessarily cater for the following environmental changes: (1) higher year-round temperatures, higher variability of rainfall incidence, and lower total winter and spring rainfall along the south of the continent; (2) higher nutrient and lime inputs as land utilisation intensifies; and (3) the grazing management requirements of the important pasture components will be increasingly defined and met in practice.The 'big four' species, perennial ryegrass, phalaris, cocksfoot and tall fescue, will continue to be the most widely sown species in temperate regions for many decades, with the latter 3 increasing most in area and genetic differentiation. However, species diversification will continue, especially with native grasses, legumes, and shrubs from fertile regions of Australia and exotics from little-explored parts of the world, such as South Africa, western North and South America, coastal Caucasus, and Iraq–Iran. By contrast, the recent high rate of species diversification in the tropics and subtropics will probably give way to a much lower rate of cultivar development by refinement and diversification within the established species. Domestication of native grasses will continue for amenity, recreational, land protection, and grazing purposes. As seed harvesting technologies and ecological knowledge improve, natural stands will become increasingly important as local sources of seed. It is suggested that many native grasses have been greatly changed by natural selection so as to withstand strong competition from introduced species under conditions of higher soil fertility and grazing pressure. Conversely, some introduced species are being selected consciously and naturally to persist in regions with irregular rainfall and less fertile soils. Therefore, the distinction between native and introduced grasses may be disappearing, and many populations of native species could now be as foreign to the habitats of pre-European settlement as are populations of introduced species that have been evolving here for 50–200 years. Methods used for genetic improvement will continue to be selection among both overseas accessions and the many native and introduced populations that have responded to natural selection in Australia. As well, there will be deliberate recurrent crossing and selection programs in both native and introduced species for specific purposes and environments. Increasingly, molecular biology methods will complement traditional ones, at first by the provision of DNA markers to assist the selection of complex traits, and for proving distinctness to obtain Plant Breeders' Rights for new cultivars. Later, genetic engineering will be used to manipulate nutritive value, resistance to fungal and viral diseases, and breeding systems, especially cytoplasmic male sterility and apomixis, to utilise heterosis in hybrid cultivars of grasses, particularly for dairying and intensive meat production.Areas where the practice and management of grass breeding and selection programs could be improved are highlighted throughout the review, and reiterated in a concluding statement. Most problems appear to stem from inadequate training in population ecology, population genetics, evolution, and quantitative inheritance.

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Lambkin, KJ. „Revision of the Australian scorpion-fly genus Harpobittacus (Mecoptera : Bittacidae)“. Invertebrate Systematics 8, Nr. 4 (1994): 767. http://dx.doi.org/10.1071/it9940767.

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Harpobittacus Gerstaecker is the largest of the six genera of Australian Bittacidae. Adults occur in eastern, south-eastern and south-western Australian eucalypt woodland and coastal heathland during spring and summer and sometimes autumn. The genus contains 11 species, which are diagnosed in the present revision: H. australis (Klug) [= australis rubripes Riek, syn. nov., = corethrarius (Rambur), = intermedius (Selys-Longchamps)] (south-east Australia, including Tasmania); H. albatus Riek, stat. nov. (= limnaeus Smithers, syn. nov.) (coastal eastern Australia); H. christine, sp. nov. (inland south-east Queensland); H. tillyardi Esben-Petersen ( = nigratus Navás) (coastal eastern Australia); H. rubricatus Riek (inland south-east Australia); H. scheibeli Esben-Petersen (= brewerae Smithers, syn. nov.) (inland and coastal eastern Australia); H. septentrionis, sp. nov. (coastal north Queensland); H. nigriceps (Selys-Longchamps) (mainland south-east Australia); H. similis Esben-Petersen, H. quasisimilis, sp. nov., and H. phaeoscius Riek (all south-west Western Australia). Cladistic analysis has produced the following hypothesis of relationships: (((australis (albatus christine)) (tillyardi rubricatus)) ((similis quasisimilis) ((scheibeli septentrionis) (nigriceps phaeoscius))). Immediate sister-species show little or no overlap in their geographic distributions.

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Wheeler, SH, und DR King. „The European Rabbit in South- Western Australia II. Reproduction“. Wildlife Research 12, Nr. 2 (1985): 197. http://dx.doi.org/10.1071/wr9850197.

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'The reproduction of the European rabbit, Oryctolagus cuniculus (L.), at two intensive study sites in south-western Australia is compared with reproductive data from rabbits taken throughout the coastal and inland districts of the south-west region. South-western Australia has hot, arid summers and cool wet winters. Rabbit breeding in the region is characteristic of that in Mediterranean climates, with a winter breeding season which begins when pastures germinate with the initial winter rainfall (April-May) and ceases when the pastures dry out at the end of the year. Unseasonal cyclonic rain can promote pasture growth in summer, leading to limited breeding. At all times of year there were some fertile males, with fewest at the height of summer, followed by an increase before the winter breeding season. Near the coast, male fertility increased more rapidly than further inland. At our two study sites at Cape Naturaliste (on the coast) and Chidlow (55 km inland) the pattern was similar to that in the coastal district. Production of kittens was greater near the coast than further inland, because near the coast there was a high early peak in incidence of pregnancy, a second peak late in the year, and litters remained large throughout the breeding season. In the inland district, the early incidence of pregnancy was lower, there was no second peak, and litter sizes fell at the end of the year. Female reproduction at Cape Naturaliste was typical of that in the coastal district, but that at Chidlow was typical of the inland. The second peak of pregnancy at Cape Naturaliste was due to intensive breeding by subadults born earlier in the year. The differences in female reproduction and productivity between the coastal and inland districts are probably because pasture growth begins earlier and is better in the more fertile coastal areas than in the inland. That nutrition is better for rabbits in the coastal areas than in the inland is reflected in higher growth rates of kittens at Cape Naturaliste than at Chidlow. It is postulated, on the basis of the literature and the results of our studies, that the factor which determines whether rabbits will breed is the presence of growing vegetation, and that the intensity of breeding is influenced by a seasonal cycle in fertility.

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Lenanton, RCJ, DI Heald, M. Platell, M. Cliff und J. Shaw. „Aspect of the reproductive biology of the Gummy Shark, Mustelus antarcticus Gunther, from waters off the South coast of Western Australia“. Marine and Freshwater Research 41, Nr. 6 (1990): 807. http://dx.doi.org/10.1071/mf9900807.

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The gummy shark (Mustelus antarcticus) is a major target species in two substantial shark fisheries that operate in temperate Australian waters. Data on the reproductive biology of M. antarcticus in the waters off south-western Australia were obtained from samples collected by commercial vessels operating from Albany to Esperance, Western Australia. The samples contained a ratio of four females to one male. M. antarcticus is a viviparous, aplacental species. Males mature at a smaller size than females. Since the overwhelming majority of sharks sampled were mature, it was not possible to estimate precisely the mean size at which sexual maturity was attained. Examination of seasonal changes in the development of ova and testes, in uterine contents, and in embryo growth established that the period of parturition, mating and ovulation occurred over the 3 months between early November and early February. The gestation period was 11-12 months. Full-term embryos ranged in size from 30 to 36 cm total length and occurred in a sex ratio of one male to one female. The ovarian and gestational cycles proceed concurrently, with reproduction occurring annually. Only one of the 224 females analysed for uterine content was considered to be in a true post-partum condition. The number of embryos (N) per mother increased with the length of the mother (L) according to the regression N = exp(-4.13398 + 0.049171L). The reproductive biology of females collected off Albany and Esperance differed in some respects from that of females collected off south-eastern Australia.

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Cochrane, HR, G. Scholz und AME Vanvreswyk. „Sodic soils in Western Australia“. Soil Research 32, Nr. 3 (1994): 359. http://dx.doi.org/10.1071/sr9940359.

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Sodic soils are common throughout Western Australia, particularly in the south-west agricultural area where they occur mainly as duplex or gradational profiles. Soils with sodic properties are dominant in 26% of the state; saline-sodic sediments and soils in intermittent streams, lakes and estuarine plains occupy a further 5%. Sodic soils are moderately common throughout the south and western portion of the rangeland areas (38% of the state). The south-west coastal sands and the desert and rangeland soils to the north and east of the state are rarely sodic. Although sodicity has been recognized as a discrete problem in W.A. soils since the 1920s, the extent and severity of sodicity has been satisfactorily described only for small areas of the state and most land managers are unaware of the role sodicity plays in limiting the productivity of their soils. Sodicity is implicated in a diversity of problems for both agricultural and non-agricultural uses of Western Australian soils. Subsoil impermeability is probably the most widespread of these, but no comprehensive, quantitative assessment of the influence of exchangeable sodium on subsoil properties has been undertaken. Topsoil sodicity is much less extensive but can severely restrict land productivity, particularly on sandy loam and finer textured soils which set hard when dry. The physical behaviour of Western Australian topsoils cannot usefully be predicted from measurements of exchangeable sodium alone because soils differ so greatly in their response to changing exchangeable sodium. Some remain structurally stable at ESP values >15 while others are so 'sodium-sensitive' that they exhibit highly dispersive behaviour at ESP values as low as 2%. Land values over much of the dryland farming and pastoral areas of W.A. do not justify sustained use of amendments which would reduce soil exchangeable sodium contents. Efficient management of sodic soils in these areas must rely on the prevention of degradation and the use of biological and physical means to maintain adequate soil physical properties. Effective restoration of degraded sodic soils, however, often does require application of inorganic amendments in combination with tillage to initiate structural recovery. Sodicity is currently not considered to be a problem at any of the three main irrigation areas in W.A., but all have sodic soil within their potentially irrigable lands, which may limit their future expansion.

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McCosker, Erin, Claire H. Davies und Lynnath E. Beckley. „Oceanographic influence on coastal zooplankton assemblages at three IMOS National Reference Stations in Western Australia“. Marine and Freshwater Research 71, Nr. 12 (2020): 1672. http://dx.doi.org/10.1071/mf19397.

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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.

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McAuley, R. B., B. D. Bruce, I. S. Keay, S. Mountford, T. Pinnell und F. G. Whoriskey. „Broad-scale coastal movements of white sharks off Western Australia described by passive acoustic telemetry data“. Marine and Freshwater Research 68, Nr. 8 (2017): 1518. http://dx.doi.org/10.1071/mf16222.

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Movements of 89 acoustically tagged subadult and adult white sharks (Carcharodon carcharias) were monitored off the south and west coasts of Western Australia (WA) between December 2008 and May 2016 by a network of up to 343 passive acoustic receivers. In all, 290 inter-regional movements, totalling 185092km were recorded for 73 of these sharks. Estimated rates of movement in excess of 3kmh–1 (mean 1.7kmh–1; maximum 5.6kmh–1) were common, even over distances of thousands of kilometres. Detections indicated that white sharks may be present off most of the south and lower west coasts of WA throughout the year, although they are more likely to be encountered during spring and early summer and are least likely to be present during late summer and autumn. There was limited evidence of predictable return behaviour, seasonal movement patterns or coordination of the direction and timing of individual shark’s movements. Nevertheless, the data suggest that further analyses of movements in relation to ecological factors may be useful predictors of shark activity at local scales. It is hoped that these data may be useful for informing public safety initiatives aimed at mitigating the risks associated with human encounters with white sharks off the WA coast.

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Hodgkin, Ernest P., und Patrick Hesp. „Estuaries to salt lakes: Holocene transformation of the estuarine ecosystems of south-western Australia“. Marine and Freshwater Research 49, Nr. 3 (1998): 183. http://dx.doi.org/10.1071/mf96109.

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When the estuaries of south-western Australia were first flooded by the Holocene marine transgression about 7000 years before present (BP), most were enclosed by limestone barrier dunes. Coastal sand drift built bars and flood-tide deltas in the narrow entrances, but until about 3500 years BP the estuaries remained tidal-dominated systems with a diverse marine–estuarine fauna. Now the bars/deltas so obstruct the small tides that estuary water is fresh in winter and marine to hypersaline in summer; the estuaries are river-flow-dominated systems and the ecosystems are characterised by a restricted euryhaline estuarine biota. Some estuaries are still permanently open, their bars/deltas never close, and some are seasonally open, their bars open with river flow in winter and close in summer. Other estuaries are normally closed, their bars remain closed for several years and break with episodic flood flow, or are permanently closed coastal salt lakes with bars that never or rarely break: they can become grossly hypersaline and may dry up altogether. An hypothesis to explain this Holocene transformation of the estuaries attributes it principally to sedimentary processes in an environment where river flow is highly seasonal, tides are microtidal, there was a fall in sea level, and there are differences in the volume and periodicity of flow and the degree of shelter to the entrances from the prevailing south-west winds and swell.

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Dawes, W., R. Ali, S. Varma, I. Emelyanova, G. Hodgson und D. McFarlane. „Modelling the effects of climate and land cover change on groundwater recharge in south-west Western Australia“. Hydrology and Earth System Sciences Discussions 9, Nr. 5 (10.05.2012): 6063–99. http://dx.doi.org/10.5194/hessd-9-6063-2012.

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Abstract. The groundwater resource contained within the sandy aquifers of the Swan Coastal Plain, south west Western Australia, provides approximately 60% of the drinking water for the metropolitan population of Perth. Rainfall decline over the past three decades coupled with increasing water demand from a growing population has resulted in falling dam storage and groundwater levels. Projected future changes in climate across south-west Western Australia consistently show a decline in annual rainfall of between 5 and 15%. There is expected to be a continuing reduction of diffuse recharge across the Swan Coastal Plain. This study aims to quantify the change in groundwater recharge in response to a range of future climate and land cover patterns across south-west Western Australia. Modelling the impact on the groundwater resource of potential climate change was achieved with a dynamically linked unsaturated/saturated groundwater model. A Vertical Flux Manager was used in the unsaturated zone to estimate groundwater recharge using a variety of simple and complex models based on land cover type (e.g. native trees, plantation, cropping, urban, wetland), soil type, and taking into account the groundwater depth. These recharge estimates were accumulated on a daily basis for both observed and projected climate scenarios and used in a MODFLOW simulation with monthly stress periods. In the area centred on the city of Perth, Western Australia, the patterns of recharge change and groundwater level change are not consistent spatially, or consistently downward. In the Dandaragan Plateau to the north-east of Perth there has been groundwater level rise since the 1970s associated with land clearing, and with rainfall projected to reduce the least in this area the groundwater levels are estimated to continue to rise. Along the coastal zone north of Perth there is an interaction between projected rainfall decline and legislated removal to pine forests. This results in areas of increasing recharge and rising water levels into the future despite a drying climate signal. To the south of Perth city there are large areas where groundwater levels are close to the land surface and not expected to change more than 1m upward or downward over the next two decades; it is beyond the accuracy of the model to conclude any definite trend. In the south western part of the study area, the patterns of groundwater recharge are dictated primarily by soil, geology and land cover. In the sandy Swan (northern boundary) and Scott Coastal Plains (southern boundary) there is little response to future climates, because groundwater levels are shallow and much rainfall is rejected recharge. The profile dries out more in summer but this allows more rainfall to infiltrate in winter. Until winter recharge is insufficient to refill the aquifers these areas will not experience significant falls in groundwater levels. On the Blackwood Plateau however, the combination of native vegetation and clayey surface soils that restrict possible infiltration and recharge mean the area is very sensitive to climate change. With low capacity for recharge and low storage in the aquifers, small reductions in recharge can lead to large reductions in groundwater levels. In the northern part of the study area both climate and land cover strongly influence recharge rates. Recharge under native vegetation is minimal and is relatively higher where grazing and pasture systems have been introduced after clearing of native vegetation. In some areas the low recharge values can be reduced to almost zero, even under dryland agriculture, if the future climate becomes very dry. In the Albany Area the groundwater resource is already over allocated, and the combination of existing permanent native vegetation with decreasing annual rainfall indicate reduced recharge. The area requires a reduction in groundwater abstraction to maintain the sustainability of the existing resource.

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Dawes, W., R. Ali, S. Varma, I. Emelyanova, G. Hodgson und D. McFarlane. „Modelling the effects of climate and land cover change on groundwater recharge in south-west Western Australia“. Hydrology and Earth System Sciences 16, Nr. 8 (14.08.2012): 2709–22. http://dx.doi.org/10.5194/hess-16-2709-2012.

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Abstract. The groundwater resource contained within the sandy aquifers of the Swan Coastal Plain, south-west Western Australia, provides approximately 60 percent of the drinking water for the metropolitan population of Perth. Rainfall decline over the past three decades coupled with increasing water demand from a growing population has resulted in falling dam storage and groundwater levels. Projected future changes in climate across south-west Western Australia consistently show a decline in annual rainfall of between 5 and 15 percent. There is expected to be a reduction of diffuse recharge across the Swan Coastal Plain. This study aims to quantify the change in groundwater recharge in response to a range of future climate and land cover patterns across south-west Western Australia. Modelling the impact on the groundwater resource of potential climate change was achieved with a dynamically linked unsaturated/saturated groundwater model. A vertical flux manager was used in the unsaturated zone to estimate groundwater recharge using a variety of simple and complex models based on climate, land cover type (e.g. native trees, plantation, cropping, urban, wetland), soil type, and taking into account the groundwater depth. In the area centred on the city of Perth, Western Australia, the patterns of recharge change and groundwater level change are not consistent spatially, or consistently downward. In areas with land-use change, recharge rates have increased. Where rainfall has declined sufficiently, recharge rates are decreasing, and where compensating factors combine, there is little change to recharge. In the southwestern part of the study area, the patterns of groundwater recharge are dictated primarily by soil, geology and land cover. In the sand-dominated areas, there is little response to future climate change, because groundwater levels are shallow and much rainfall is rejected recharge. Where the combination of native vegetation and clayey surface soils restricts possible infiltration, recharge rates are very sensitive to reductions in rainfall. In the northern part of the study area, both climate and land cover strongly influence recharge rates. Recharge under native vegetation is minimal and is relatively higher where grazing and pasture systems have been introduced after clearing of native vegetation. In some areas, the recharge values can be reduced to almost zero, even under dryland agriculture, if the future climate becomes very dry.

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Hnatiuk, RJ, und BR Maslin. „Phytogeography of Acacia in Australia in Relation to Climate and Species-Richness“. Australian Journal of Botany 36, Nr. 4 (1988): 361. http://dx.doi.org/10.1071/bt9880361.

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This paper reports on the kinds of geographic patterns encountered in the distribution of Australian species of Acacia and on some climatic correlates of these patterns. The analyses were based on distribution data of 837 species mapped on a 1° x 1.5° grid. The area of highest density of species was the south-west corner of the continent, especially adjacent to the major boundary separating the Arid Zone from the more humid South West Botanical Province. The second major centre of richness occurred in eastern Australia south of the Tropic of Capricorn along the topographically heterogeneous Great Dividing Range. Secondary centres of species-richness occurred in northern and north-eastern Australia, a number of rocky tablelands of the Arid Zone and in western Victoria. The principal species-poor areas were located in sandy and some riverine areas of the Arid Zone, in temperate forests of Tasmania and in coastal areas of the north of the continent. The geographic patterns of each section of Acacia, when combined with those of species density, highlighted the tropical (section Juliflorae) v. temperate areas (sections Phyllodineae, Pulchellae, Botrycephalae and Alatae). The numerical classification of grids resulted in the recognition of eight major Acacia areas, arranged under four Acacia regions: (1) South-west; (2) Eastern, comprising a southern and a northern area; (3) Northern, comprising an eastern and a western area; (4) Central, comprising a south-east, a central and a north-west area. A discriminant function analysis indicated that precipitation was more important than temperature in distinguishing between areas. Discussion of the potential evolutionary significance of these findings and brief comparison with other biogeographic studies are given.

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Wheeler, M. A., und M. Byrne. „Congruence between phylogeographic patterns in cpDNA variation in Eucalyptus marginata (Myrtaceae) and geomorphology of the Darling Plateau, south-west of Western Australia“. Australian Journal of Botany 54, Nr. 1 (2006): 17. http://dx.doi.org/10.1071/bt05086.

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Phylogeographic patterns in the cp genome of Eucalyptus marginata Don ex Sm., a species common in the mesic region of south-western Australia, were investigated by using RFLP analysis. The chloroplast diversity was structured into two geographically distinct lineages and nested clade analysis inferred historical fragmentation as the major influence on the phylogeographic pattern. The lineages were separated along the geomorphological boundary of the Darling Scarp, which separates the Coastal Plain from the Darling Plateau. The divergence between the lineages is consistent with uplifting of the Darling Plateau in the late Neogene. Further geographic structuring in haplotype distributions was evident in the forest lineage on the Darling Plateau, where one sublineage was present in the central forest region and another was restricted to the south-eastern region. The level of divergence between these sublineages was similar to that between divergent lineages that have been identified in comparative phylogeographic studies of cpDNA variation in three species widespread throughout south-western Australia. In these species, divergence was attributed to the influence of significant changes in climatic oscillations across the semi-arid region during the mid-Pleistocene. The divergence identified in this study indicates that the influence of climatic change was widespread throughout south-western Australia, including the mesic, higher-rainfall region.

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Kerle, J. A., C. Kimmorley und J. M. Old. „An inland population of the common ringtail possum (Pseudocheirus peregrinus) at Black Rock Ridge, New South Wales: a preliminary ecological assessment“. Australian Mammalogy 35, Nr. 2 (2013): 236. http://dx.doi.org/10.1071/am12047.

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The common ringtail possum (Pseudocheirus peregrinus) is considered abundant throughout its distribution in eastern Australia but appears to be declining at a regional level in inland New South Wales. Previous studies of the common ringtail possum in south-eastern Australia have focussed on coastal populations and little is known about the ecology of inland populations. In south-western Australia studies of the closely related western ringtail possum (Pseudocherius occidentalis) have found that coastal populations differ from inland populations, particularly in their nesting behaviour. In this preliminary study of an inland population of the common ringtail possum at Black Rock Ridge in central west New South Wales population density has been estimated and the habitat and nesting preference assessed. Up to one ringtail per hectare and 4.5 ringtails per spotlight hour were recorded. Tree hollows appeared to be the preferred nest site, with possums seen entering hollows during spotlighting and no dreys being located. Threats to common ringtail possums at Black Rock Ridge include the isolation of the remnant ridge vegetation within an extensively cleared landscape and the associated change in fire regimes. Within this landscape there has been an extensive reduction in available habitat, and an overall lack of habitat connectivity has placed ringtail possums at an increased risk of predation.

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Shearer, B. L., C. E. Crane und A. Cochrane. „Quantification of the susceptibility of the native flora of the South-West Botanical Province, Western Australia, to Phytophthora cinnamomi“. Australian Journal of Botany 52, Nr. 4 (2004): 435. http://dx.doi.org/10.1071/bt03131.

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This study compares, for the first time, variation in estimates of susceptibility of native flora to Phytophthora cinnamomi Rands among four databases and proposes an estimate of the proportion of the flora of the South-West Botanical Province of Western Australia that is susceptible to the pathogen. Estimates of the susceptibility of south-western native flora to P. cinnamomi infection were obtained from databases for Banksia woodland of the Swan Coastal Plain, jarrah (Eucalyptus marginata Donn. ex Smith) forest, the Stirling Range National Park and Rare and Threatened Flora of Western Australia. For the woodland, forest and national park databases, hosts were naturally infected in uncontrolled diverse natural environments. In contrast, threatened flora were artificially inoculated in a shadehouse environment. Considerable variation occurred within taxonomic units, making occurrence within family and genus poor predictors of species susceptibility. Identification of intra-specific resistance suggests that P. cinnamomi could be having a strong selection pressure on some threatened flora at infested sites and the populations could shift to more resistant types. Similar estimates of the proportion of species susceptible to P. cinnamomi among the databases from the wide range of environments suggests that a realistic estimate of species susceptibility to P. cinnamomi infection in the south-western region has been obtained. The mean of 40% susceptible and 14% highly susceptible equates to 2284 and 800 species of the 5710 described plant species in the South-West Botanical Province susceptible and highly susceptible to P. cinnamomi, respectively. Such estimates are important for determining the cost of disease to conservation values and for prioritising disease importance and research priorities. P. cinnamomi in south-western Australia is an unparalleled example of an introduced pathogen with a wide host range causing immense irreversible damage to unique, diverse but mainly susceptible plant communities.

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Kuhn, M., D. Tuladhar und R. Corner. „Visualising the spatial extent of predicted coastal zone inundation due to sea level rise in south-west Western Australia“. Ocean & Coastal Management 54, Nr. 11 (November 2011): 796–806. http://dx.doi.org/10.1016/j.ocecoaman.2011.08.005.

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Singor, Marcus. „Eurasian Hobby Falco subbuteo: A review of recent records from Western Australia and Australian external territories“. Australian Field Ornithology 38 (2021): 119–23. http://dx.doi.org/10.20938/afo38119123.

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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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Shearer, B. L., C. E. Crane, R. G. Fairman und M. J. Grant. „Occurrence of Armillaria luteobubalina and Pathogen-mediated Changes in Coastal Dune Vegetation of South-western Australia“. Australian Journal of Botany 45, Nr. 5 (1997): 905. http://dx.doi.org/10.1071/bt96084.

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Sixty-two Armillaria luteobubalina Watling & Kiledisease centres were assessed along the coast from near Cervantes, 160 kmnorth-west of Perth, to Cape Arid, 120 km east of Esperance. Disease centresranged from 0.02 to 6.5 ha in size (mean ± s.e., 1.7 ± 0.2 ha).Most disease centres were active, with mainly old deaths occurring in only7% of centres. Impact was low in only 3% of centres. Diseasecentres mainly occurred on calcareous sands of Holocene dune systems.Susceptible hosts from the Proteaceae, Mimosaceae and Myrtaceae tended to bedominant small trees or shrubs and their death resulted in centres composedmainly of sedges or small shrubs and ground-cover species from a range offamilies. Percentage cover of susceptible plant species was significantly lessin disease centres than adjacent healthy areas. Cover of resistant speciestended to be greater in disease centres than adjacent healthy areas, althoughdifferences were not significant. In association with changes in communitystructure, infection resulted in more bare ground in disease centres thanamongst healthy vegetation. Infection had minimal effect on species richness.The mortality progress curve for the susceptible speciesDryandra sessilis (Knight) Domin increased at a meanapparent infection rate of 0.31 ± s.e. 0.12year-1. A disease centre extended at the rate of 0.004ha year-1 between 1964 and 1983 and 0.07 hayear-1 during the period 1981–1989. Diseaseextension per year was not correlated with yearly rainfall. Threatened taxakilled by A. luteobubalina included the rare andendangered Banksia brownii Baxter ex R.Br.,B. occidentalis R.Br. subsp.formosa Hopper, andB. verticillata R.Br. This is the first report ofdisease significantly altering the structure and composition of coastalvegetation of south-western Australia.Armillaria luteobubalina is a significant additional,and hitherto unrecognised, selection pressure on coastal dune vegetationcommunities, and an important consideration in their management andconservation.

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Start, A. N. „The mistletoe flora of southern Western Australia, with a particular reference to host relationships and fire“. Australian Journal of Botany 63, Nr. 8 (2015): 636. http://dx.doi.org/10.1071/bt15028.

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The mistletoe flora of southern Western Australia was studied over a 30-year period with a particular emphasis on distributions, host relationships and fire. The study area encompassed Western Australia south of ~26° S. It included all the South-west Botanical Province and southern components of the Eremaean Botanical Province, with the northern boundary corresponding with bioregional boundaries. Vegetation ranges from wet and dry sclerophyll forest through woodlands and heaths to deserts. The mistletoe flora comprises 21 taxa, 19 in the Loranthaceae and two in the Santalaceae. They infect 153 species in 25 genera and 15 families. The Fabaceae provides hosts to more taxa than any other family; however, the genus with most host species, Eucalyptus (Myrtaceae), supports only two mistletoe species, one of which barely enters the study area. Melaleuca (also Myrtaceae) is host to seven species. The number of mistletoe species per bioregion ranges from 0 to 18, with 12 species in the seven bioregions of the South-west Botanical Province and 20 in the six bioregions of Eremaean Botanical Province that are within the study area. In both provinces, diversity is lower in coastal areas and higher in more arid, inland areas. Most mistletoe habitats in the study area are fire-prone. One species is probably capable of resprouting whereas all other taxa are obligate seeders. With no means of in situ seed storage, post-fire recovery depends on seed importation. Fire is the most pervasive (but not the only) threatening process operating today. However, fire management in more populous agricultural and urban areas safeguards many populations in the South-west Province.

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Allen, Simon J., Daniele D. Cagnazzi, Amanda J. Hodgson, Neil R. Loneragan und Lars Bejder. „Tropical inshore dolphins of north-western Australia: Unknown populations in a rapidly changing region.“ Pacific Conservation Biology 18, Nr. 1 (2012): 56. http://dx.doi.org/10.1071/pc120056.

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Australian Snubfin Orcaella heinsohni, Indo-Pacific Humpback Sousa chinensis and Indo-Pacific Bottlenose Dolphins Tursiops aduncus inhabit Australia’s tropical north-western coastline, a region undergoing extensive port development associated with the massive expansion of the oil, gas and mining industries. The current lack of data on dolphin population sizes or trends precludes impact assessments of developments on these protected species. Furthermore, the Western Australian and Commonwealth Government conservation listings of tropical inshore dolphins do not reflect their international listings. From April to July, 2010, we conducted ad hoc boat-based surveys (n=55) of inshore delphinids at seven sites across north-western Australia from Coral Bay in the south (23.1°S: 113.8°E) to Cable Beach in the north (17.9°S: 122.2°E). We documented the locations of these three species from which we obtained photoidentification and biopsy data, as well as reports of Australian Snubfin Dolphin sightings from researchers and community groups. The data from this limited field effort confirm that Indo-Pacific Humpback and Indo-Pacific Bottlenose Dolphins occur in the waters adjacent to each north-western Australian urban centre and show that the range of the Australian Snubfin Dolphin extends considerably further south-west than previously reported. Given the scale of coastal developments and the vulnerability of isolated cetacean populations to fragmentation or extirpation, assessments of the viability of dolphin populations are required. Our data suggest that the Australian Snubfin, Indo-Pacific Humpback and Indo-Pacific Bottlenose Dolphins need to be considered as likely to be impacted by coastal developments across north-western Australia.

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Macphail, Michael K., und Robert S. Hill. „What was the vegetation in northwest Australia during the Paleogene, 66–23million years ago?“ Australian Journal of Botany 66, Nr. 7 (2018): 556. http://dx.doi.org/10.1071/bt18143.

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Fossil pollen and spores preserved in drillcore from both the upper South Alligator River (SARV) in the Kakadu National Park, Northern Territory and the North-West Shelf, Western Australia provide the first record of plants and plant communities occupying the coast and adjacent hinterland in north-west Australia during the Paleogene 66 to 23million years ago. The palynologically-dominant woody taxon is Casuarinaceae, a family now comprising four genera of evergreen scleromorphic shrubs and trees native to Australia, New Guinea, South-east Asia and Pacific Islands. Rare taxa include genera now mostly restricted to temperate rainforest in New Guinea, New Caledonia, New Zealand, South-East Asia and/or Tasmania, e.g. Dacrydium, Phyllocladus and the Nothofagus subgenera Brassospora and Fuscospora. These appear to have existed in moist gorges on the Arnhem Land Plateau, Kakadu National Park. No evidence for Laurasian rainforest elements was found. The few taxa that have modern tropical affinities occur in Eocene or older sediments in Australia, e.g. Lygodium, Anacolosa, Elaeagnus, Malpighiaceae and Strasburgeriaceae. We conclude the wind-pollinated Oligocene to possibly Early Miocene vegetation in the upper SARV was Casuarinaceae sclerophyll forest or woodland growing under seasonally dry conditions and related to modern Allocasuarina/Casuarina formations. There are, however, strong floristic links to coastal communities growing under warm to hot, and seasonally to uniformly wet climates in north-west Australia during the Paleocene-Eocene.

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JUST, JEAN. „Siphonoecetini Just, 1983 (Crustacea, Amphipoda, Ischyroceridae) 13: Western Australian species of Bubocorophiina in Rhinoecetes, Cephaloecetes, Sinoecetes, Borneoecetes and Pararhinoecetes gen. nov.“ Zootaxa 4554, Nr. 1 (08.02.2019): 101. http://dx.doi.org/10.11646/zootaxa.4554.1.3.

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The Western Australia fauna of Bubocorophiina (Siphonoecetini) from the Albany area in the south to Port Hedland in the north-west, a coastal stretch of about 2000 km, is reported. One new genus and 11 new species are described: Rhinoecetes sinuduopopulus sp. nov., R. rockinghamia sp. nov., R. makritrichoma sp. nov., R. lowryi sp. nov., R. caetus sp. nov., R. karkharius sp. nov., R. wamus sp. nov., R. setosus sp. nov., Borneoecetes minimus sp. nov. (first record of Borneoecetes Barnard & Thomas, 1984 from Australia); Sinoecetes reni sp. nov. (first record of Sinoecetes Ren, 2012 from Australia), and Pararhinoecetes bicornis gen. et sp. nov. In addition, Cephaloecetes enigmaticus, previously described from the southeast coast of Australia, is recorded in the Albany area. A key to Western Australian Bubocorophiina is presented, and the distribution around Australian of the genera in the subtribe is commented upon.

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Gilmour, James, Conrad W. Speed und Russ Babcock. „Coral reproduction in Western Australia“. PeerJ 4 (18.05.2016): e2010. http://dx.doi.org/10.7717/peerj.2010.

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Larval production and recruitment underpin the maintenance of coral populations, but these early life history stages are vulnerable to extreme variation in physical conditions. Environmental managers aim to minimise human impacts during significant periods of larval production and recruitment on reefs, but doing so requires knowledge of the modes and timing of coral reproduction. Most corals are hermaphroditic or gonochoric, with a brooding or broadcast spawning mode of reproduction. Brooding corals are a significant component of some reefs and produce larvae over consecutive months. Broadcast spawning corals are more common and display considerable variation in their patterns of spawning among reefs. Highly synchronous spawning can occur on reefs around Australia, particularly on the Great Barrier Reef. On Australia’s remote north-west coast there have been fewer studies of coral reproduction. The recent industrial expansion into these regions has facilitated research, but the associated data are often contained within confidential reports. Here we combine information in this grey-literature with that available publicly to update our knowledge of coral reproduction in WA, for tens of thousands of corals and hundreds of species from over a dozen reefs spanning 20° of latitude. We identified broad patterns in coral reproduction, but more detailed insights were hindered by biased sampling; most studies focused on species ofAcroporasampled over a few months at several reefs. Within the existing data, there was a latitudinal gradient in spawning activity among seasons, with mass spawning during autumn occurring on all reefs (but the temperate south-west). Participation in a smaller, multi-specific spawning during spring decreased from approximately one quarter of corals on the Kimberley Oceanic reefs to little participation at Ningaloo. Within these seasons, spawning was concentrated in March and/or April, and October and/or November, depending on the timing of the full moon. The timing of the full moon determined whether spawning was split over two months, which was common on tropical reefs. There were few data available for non-Acroporacorals, which may have different patterns of reproduction. For example, the massivePoritesseemed to spawn through spring to autumn on Kimberley Oceanic reefs and during summer in the Pilbara region, where other common corals (e.g.Turbinaria&Pavona) also displayed different patterns of reproduction to theAcropora. The brooding corals (Isopora&Seriatopora) on Kimberley Oceanic reefs appeared to planulate during many months, possibly with peaks from spring to autumn; a similar pattern is likely on other WA reefs. Gaps in knowledge were also due to the difficulty in identifying species and issues with methodology. We briefly discuss some of these issues and suggest an approach to quantifying variation in reproductive output throughout a year.

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Brown, Alex, Lars Bejder, Daniele Cagnazzi, Guido J. Parra und Simon J. Allen. „The North West Cape, Western Australia: A Potential Hotspot for Indo-Pacific Humpback Dolphins Sousa chinensis?“ Pacific Conservation Biology 18, Nr. 4 (2012): 240. http://dx.doi.org/10.1071/pc120240.

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Indo-Pacific Humpback Dolphins Sousa chinensis (Humpback Dolphins hereafter) are listed as ‘near threatened’ on an international level and ‘migratory’ in Australian waters. There is limited information on Humpback Dolphins in Western Australian State waters, where the species remains unlisted. This lack of knowledge hinders the management and conservation of the species in a region of rapidly increasing coastal development. We conducted opportunistic boat-based surveys in April 2010 and present data on the location, size and composition of Humpback Dolphin groups encountered in the near-shore waters around the North West Cape, Western Australia. A total of 42 groups were encountered in a variety of habitats during 145 h on the water over ca. 80 km coastline. Group size ranged from 1 to 15, with a mean (± SE) of 5.3 (± 0.48) individuals. A total of 54 Humpback Dolphins were identified from photographs of the unique markings on their dorsal fins. The lack of a plateau in the cumulative discovery curve of identified individuals over the duration of the study suggests that only a subset of dolphins in the area was identified. This region is close to the south-western limit of the species’ Australian distribution and appears to represent an important location for Western Australian Humpback Dolphins. In light of increasing anthropogenic activity around the North West Cape and Exmouth Gulf, these preliminary findings from a limited survey effort indicate that further research into this population is required.

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Butcher, R., und K. R. Thiele. „An investigation of taxon boundaries in rare and range-restricted Synaphea (Proteaceae: Conosperminae) species from south-west Western Australia“. Australian Systematic Botany 27, Nr. 2 (2014): 119. http://dx.doi.org/10.1071/sb14015.

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The Swan Coastal Plain of south-west Western Australia has been extensively cleared since European settlement, with the fertile Pinjarra Plain land system preferentially cleared for grazing; what remains of the native vegetation is of high conservation value despite being highly fragmented and often degraded. The following six taxa of Synaphea R.Br. (Proteaceae), with conservation status corresponding to IUCN Red List categories Threatened and Data Deficient, are restricted to vegetation remnants in this region: S. stenoloba A.S.George, S. odocoileops A.S.George, S. sp. Pinjarra (R. Davis 6578), S. sp. Fairbridge Farm (D. Papenfus 696), S. sp. Pinjarra Plain (A.S. George 17182) and S. sp. Serpentine (G.R. Brand 103). Taxonomic boundaries among these morphologically similar taxa of Synaphea were investigated using morphometric analyses based on characters of leaves, inflorescences, flowers and fruits. Results allow the circumscription of the four informally named taxa from this complex, which will enable their formal description in a subsequent publication. They also provide support for several morphologically closely related taxa, including the provisional distinction of S. sp. Udumung (A.S. George 17058) from close ally S. decorticans Lindl. Two described species (S. odocoileops and S. stenoloba) and several anomalous specimens could not be adequately resolved in these analyses, and further investigation of their boundaries using molecular markers is required.

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R. Williams, Matthew. „Butterflies and day-flying moths in a fragmented urban landscape, south-west Western Australia: patterns of species richness“. Pacific Conservation Biology 15, Nr. 1 (2009): 32. http://dx.doi.org/10.1071/pc090032.

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Surveys of butterflies and day-flying moths were conducted at 46 bushland remnants in the Swan Coastal Plain, Western Australia, between 2001 and 2005. A total of 17 075 individuals was recorded, representing 35 butterfly and 5 day-flying moth species. Individual site species richness varied between one and 27 species. Two main groups of taxa were identified: (i) species that are reliant on remnant native vegetation for breeding and are entirely or predominantly restricted to remnant bushland (resident species or urban avoiders, 27 taxa); and (ii) species that now breed primarily on introduced plants and disperse readily through the urban matrix, but which also visit remnant bushland and sometimes breed there (non-resident species or urban adapters, 13 taxa). Estimated species detectability varied widely between species and seasonally, but for most taxa was consistent across the three years of the study. Peak detectability was strongly related to observed abundance, something that is well known (intuitively), but has rarely been demonstrated (quantitatively). Only one listed endangered species was recorded, the Graceful Sun-moth Synemon gratiosa which was observed in low numbers at six sites. Several species were encountered less frequently, although these have populations outside the region. Few of the surveyed remnants were considered to have an intact butterfly fauna; it is inferred that the majority had lost some or all of their original resident species. The reliance of many species on specific host plants, and the ability of some to adapt to introduced weeds, are important factors in their persistence within remnants. These bushland remnants are effectively habitat islands for butterflies and day-flying moths, and the few remaining species-rich bushlands are therefore of regional importance for conservation of this group. This paper serves as a baseline study against which to monitor any future changes to the butterfly fauna of these remnants.

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Hughes, JC, und RJ Gilkes. „Rock phosphate dissolution and bicarbonate-soluble-P in some soils from South-Western Australia“. Soil Research 32, Nr. 4 (1994): 767. http://dx.doi.org/10.1071/sr9940767.

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Samples were collected from 228 soils from the main agricultural areas of Western Australia (W.A.) and their chemical and textural properties analysed. Soils were incubated for 7 days with North Carolina rock phosphate at a rate equivalent to 1022 �g Ca g(-1) and 383 �g P g(-1) soil. Subsequently, the amount of rock phosphate (RP) that had dissolved was determined by measuring the increase in extractable calcium (�Ca) and changes in plant-available P were estimated by a sodium bicarbonate extraction (�Bic-P). Only 29 soils dissolved more than 40% of the added RP and these occur in the wettest area of W.A., to the west of the 800 mm rainfall isohyet. They represent a variety of soil types including Vertisols, Spodosols, Alfisols and Ultisols. Simple and multiple regressions were carried out to investigate the soil properties responsible for RP dissolution and associated P availability. No single soil property adequately predicted RP dissolution or concomitant changes in bicarbonate-P. Titratable acidity and sand content together explained 61% of the variance in RP dissolution; titratable acidity was the most predictive single variable for bicarbonate-P but only explained 56% of the variance. Stepwise regression showed that titratable acidity and pH(CaCl2) together explained 79% of the variance in bicarbonate-P. The most suitable soils for RP application are sandy, humic or peaty podzols where much of the dissolved P remains available to plants. The other soils (mainly red and yellow earths and Vertisols) which dissolved much RP contain larger amounts of extractable aluminium (by dithionite or oxalate) which is the soil component largely responsible for P-sorption in these W.A. soils. These results indicate that RP fertilizers will be most effective on the humic, sandy podzols of the western and southern coastal plains of WA.

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Bougher, N. L., und J. A. Friend. „Fungi consumed by translocated Gilbert's potoroos (Potorous gilbertii) at two sites with contrasting vegetation, south coastal Western Australia“. Australian Mammalogy 31, Nr. 2 (2009): 97. http://dx.doi.org/10.1071/am09012.

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Gilbert’s potoroo (Potorous gilbertii) was previously widespread in south-west Australia but is now restricted to one location – a granitic area of shrubby heath at Two Peoples Bay Nature Reserve on the south coast of Western Australia. To alleviate the threat of extinction a program is under way to establish potoroos in other locations. At Two Peoples Bay Gilbert’s potoroos feed almost exclusively on truffle fungi. However, it was not known whether potoroos translocated to any new areas would be able to rapidly access and consume fungi after translocation, or whether truffles could be a sustainable food supporting breeding populations of potoroos in translocation sites. Furthermore, it was not known whether translocation of potoroos would be successful only in areas with vegetation similar to their refuge at Two Peoples Bay. The current study addressed these questions by analysing the diet of potoroos translocated into two contrasting areas – one on Bald Island with similar topography and vegetation to that of Two Peoples Bay, and the other a 14-ha enclosure on the mainland dominated by Eucalyptus–Allocasuarina woodland. The diet of potoroos was characterised by microscopic examination of scats from individuals trapped after their translocation to these areas. At Bald Island a diverse range of fungi was consumed immediately after translocation. Four potoroos released onto the island only 4–8 days previously consumed 23 species of fungi. Consumption was sustained over time. Three potoroos released onto Bald Island 1–2 years previously and one island-born individual consumed 27 species of fungi during a two-day sampling period. Nine of the 27 fungi species were the same as those that had been consumed by the potoroos within days after their release onto the island. This indicates that production of fungi and their consumption by potoroos on the island was sustained at least 1–2 years after translocation. Potoroos bred on Bald Island during this period. During the same period, two potoroos that were moved from captivity to the mainland site (Ryedene) were consuming six species of truffles within 29 days after release, and 14 species within three months. Such data indicate that a wider selection of vegetation types and areas than just those similar to where potoroos occur at Two Peoples Bay may be able to sustain potoroos and should be investigated for future translocations.

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Braithwaite, LW, M. Maher, SV Briggs und BS Parker. „An Aerial Survey of 3 Game Species of Waterfowl (Family Anatidae) Populations in Eastern Australia“. Wildlife Research 13, Nr. 2 (1986): 213. http://dx.doi.org/10.1071/wr9860213.

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Populations of waterfowl of three game species, the Pacific black duck Anus superciliosa, grey teal A. gibberifrons, and maned duck Chenonetta jubata, were assessed by aerial survey in October 1983 within a survey region of 2 697 000 km2 of eastern Australia. The numbers of each species were assessed on all surface waters of over 1 ha, and on a sample of smaller surface waters within 10 survey bands each 30 km wide and spaced at intervals of 2� latitude from 20�30' to 38�30'S. The area within the survey bands was 324 120 km2, which gave a sampling intensity of 12.0% of the land surface area. The area of features shown as wetlands or water impoundments within the survey bands on 1 : 2 500 000 topographic maps was 19 200 km2 or 11.2% of the total area of these features in the survey region. The area of surface waters surveyed was assessed at 465 300 ha. Assessments of populations of each species were tallied for wetlands by grid cells of 6 min of 1� longitude along the survey bands (258-309 km2 depending on latitude). Distributions were then mapped, with log*10 indices of populations in each cell. Distributions of the black duck and grey teal showed a pattern of intense aggregation in limited numbers of cells, that of the maned duck was more evenly distributed. The major concentrations of the Pacific black duck were recorded in northern New South Wales and the south-eastern, western, central eastern and central coastal regions of Queensland; those of the grey teal were in south-western, western and northern New South Wales and central-eastern Queensland; the maned duck was broadly distributed over inland New South Wales with the exception of the far west, inland southern Queensland, and central northern Victoria.

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Woinarski, JCZ. „Biogeography and conservation of reptiles, mammals and birds across north-western Australia: an inventory and base for planning an ecological reserve system“. Wildlife Research 19, Nr. 6 (1992): 665. http://dx.doi.org/10.1071/wr9920665.

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The distributions of mammals (94 spp. =38% of the Australian total), land birds (252 spp. =52%), and terrestrial reptiles (269 spp. = 39%) in north-western Australia are analysed. Of these species, 133 (mostly reptiles) are restricted to this region. Reptiles (and especially endemic species) characteristically have small ranges in this area. For all three groups, diversity is highest in coastal, high rainfall areas (especially of Arnhem Land and the northern Kimberley). Such areas are relatively well represented in the existing nature reserve system. Assemblages of species are mapped, on the basis of classification of the 123 lo latitude by lo longitude cells in the region. For both mammal and bird species, four defined assemblages were distributed in high rainfall coastal areas, inland low rainfall areas and two transitional zones, all extending over a broad east-west span. Reptile assemblages show a similar initial (wet-dry) division, but then split into east and west subdivisions. For all three animal groups, transitional and inland assemblages are poorly reserved (<0.25% of land area). A total of 58 reserves occur in the region. Most are small (median 24km*2) and concentrated around population centres. Biological information is lacking for most reserves. Largely because of the dispersion of existing reserves, almost one quarter of the species considered (and about the same proportion of endemic species) are not known to occur in any conservation reserve in the region. Priorities are assigned for the placement of future reserves. The most significant additions should be in the north Kimberley, south-west Kimberley, northern fringe of the Tanami Desert, Gulf of Carpentaria hinterland and eastern Arnhem Land. The conservation of this fauna is not dependent solely on the provision of a park network, but demands also informed management of reserves and adequate environmental protection of land outside reserves.

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Wright, Ian J., und Pauline Y. Ladiges. „Geographic Variation in Eucalyptus diversifolia (Myrtaceae) and the Recognition of New Subspecies E. diversifolia subsp. hesperia and E. diversifolia subsp. megacarpa“. Australian Systematic Botany 10, Nr. 5 (1997): 651. http://dx.doi.org/10.1071/sb96019.

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Patterns of geographic variation in morphological and chemical characters are documented in Eucalyptus diversifolia Bonpl. (soap mallee, white coastal mallee). This species is found in coastal and subcoastal Australia from southern Western Australia to Cape Nelson (western Victoria), with a number of disjunctions in the intervening region. Morphological data from adult plants collected at field localities and seedlings grown under uniform conditions were analysed using univariate and multivariate methods, including oneway ANOVA, multiple comparison tests, non-metric multidimensional scaling (NMDS), nearest neighbour networks, and minimum spanning trees. Seedling material was tested for isozyme polymorphism, and adult leaf flavonoids were analysed using liquid chromatography. Morphological and chemical characters are also documented in E. aff. diversifolia, a closely related but unnamed taxon restricted to ironstone outcrops near Norseman (WA), and putative E. diversifolia- E. baxteri hybrids from Cape Nelson. Congruent patterns in data sets distinguish three groups of E. diversifolia adults and progeny: (1) those to the west of the Nullarbor disjunction; (2) South Australian populations to the east of this disjunction; and (3) those from Cape Nelson. Formal taxonomic recognition of the three forms at subspecific level is established, namely E. diversifolia subsp. diversifolia, E. diversifolia subsp. hesperia, and E. diversifolia subsp. megacarpa. Patterns of geographic affinity between populations are consistent with a hypothesis of genetic exchange between normally disjunct regional populations of E. diversifolia via coastal land-bridges exposed during periodic times of low sea level since the mid Tertiary.

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Bortolussi, G., J. G. McIvor, J. J. Hodgkinson, S. G. Coffey und C. R. Holmes. „The northern Australian beef industry, a snapshot. 3. Annual liveweight gains from pasture based systems“. Australian Journal of Experimental Agriculture 45, Nr. 9 (2005): 1093. http://dx.doi.org/10.1071/ea03098.

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The herd performance of 375 northern Australian beef producers during the 1991 and 1992 to 1995 and 1996 financial years was surveyed in 1996 and 1997. Estimates were made of annual liveweight gain from production systems based on native and improved pastures together with hormonal growth promotant use and supplementation practices. The most commonly used pasture communities for growing and finishing cattle were black speargrass and brigalow communities in Central Coastal Queensland and the Central Highlands; black speargrass in Northern Queensland; Mitchell grass and gidgee in Central Western and North-west Queensland; Mitchell grass in the Northern Territory and northern Western Australia regions and brigalow–softwood scrub in the Maranoa South West. There was considerable variation and overlap in the production ranges of the various pasture communities. The estimates and ranges of annual liveweight gains were comparable with measurements from scientific and commercial studies for 3 major pasture communities (black speargrass, brigalow and Mitchell grass). On this basis, the annual liveweight gain data are considered to represent sound estimates of performance from the pasture communities and husbandry systems in use in northern Australia. Mean annual gains for pasture communities in the more northern regions tended to be <150 kg/year. Half the survey group used hormonal growth promotants but use varied between regions with lowest levels in Central Coastal Queensland (30%) and highest usage in the Central Highlands (59%). Steers and bullocks were the most commonly implanted class of cattle. Supplementation periods tended to be longest in more northern regions. Nitrogen was a component of >90% of the supplements offered. The percentage of producers supplementing various classes of cattle varied widely (0–77%). Steers were often the least supplemented class and weaners were the most common. The highest percentage of producers (>68%) supplementing weaners was found in North-west and Northern Queensland, the Northern Territory and northern Western Australia. Significant correlations explaining 3–23% of the variance were found between annual liveweight gain and latitude and/or longitude for native black speargrass and Mitchell grass pasture communities and improved brigalow pastures. Generally, annual liveweight gain increased with increasing latitude and longitude. The results are discussed in relation to herd management practices and sources of variation in the northern Australian production environment.

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Islam, Farhana, und Monzur Alam Imteaz. „Use of Teleconnections to Predict Western Australian Seasonal Rainfall Using ARIMAX Model“. Hydrology 7, Nr. 3 (05.08.2020): 52. http://dx.doi.org/10.3390/hydrology7030052.

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Increased demand for engineering propositions to forecast rainfall events in an area or region has resulted in developing different rainfall prediction models. Interestingly, rainfall is a very complicated natural system that requires consideration of various attributes. However, regardless of the predictability performance, easy to use models have always been welcomed over the complex and ambiguous alternatives. This study presents the development of Auto–Regressive Integrated Moving Average models with exogenous input (ARIMAX) to forecast autumn rainfall in the South West Division (SWD) of Western Australia (WA). Climate drivers such as Indian Ocean Dipole (IOD) and El Nino Southern Oscillation (ENSO) were used as predictors. Eight rainfall stations with 100 years of continuous data from two coastal regions (south coast and north coast) were selected. In the south coast region, Albany (0,1,1) with exogenous input DMIOct–Nino3Nov, and Northampton (0,1,1) with exogenous input DMIJan–Nino3Nov were able to forecast autumn rainfall 4 months and 2 months in advance, respectively. Statistical performance of the ARIMAX model was compared with the multiple linear regression (MLR) model, where for calibration and validation periods, the ARIMAX model showed significantly higher correlations (0.60 and 0.80, respectively), compared to the MLR model (0.44 and 0.49, respectively). It was evident that the ARIMAX model can predict rainfall up to 4 months in advance, while the MLR has shown strict limitation of prediction up to 1 month in advance. For WA, the developed ARIMAX model can help to overcome the difficulty in seasonal rainfall prediction as well as its application can make an invaluable contribution to stakeholders’ economic preparedness plans.

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Summers, KJ, BH O'Connor und DR Fox. „Radiological consequences of amending soils with bauxite residue gypsum mixtures“. Soil Research 31, Nr. 4 (1993): 533. http://dx.doi.org/10.1071/sr9930533.

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This paper reports on the gamma (�) radiation flux from sandy soils of the Swan Coastal Plain treated with bauxite residue/gypsum at various application rates and assesses the radiological significance of soil amendment in relation to currently accepted standards. Amendment rates of up to 2000 t ha-1 of bauxite residue were used. There is a linear increase of incremental � dose with increasing rate of residue. The 1 mSv limit for incremental � dose exposure for the general public is reached for 100% occupancy at an amendment rate of 1500 t ha-1 of bauxite residue. The gamma rate of approximately 0.15 �Gy h-1 is similar to that for soils of much of the area between Bunbury and Capel in the south-west of Western Australia and is significantly lower than levels for Minninup beach where there are deposits of mineral sands.

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LAST, PETER R., JUSTIN A. CHIDLOW und LEONARD J. V. COMPAGNO. „A new wobbegong shark, Orectolobus hutchinsi n. sp. (Orectolobiformes: Orectolobidae) from southwestern Australia“. Zootaxa 1239, Nr. 1 (21.06.2006): 35. http://dx.doi.org/10.11646/zootaxa.1239.1.3.

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Orectolobus hutchinsi n. sp.. is a moderate-sized wobbegong shark found in shallow continental shelf habitats off Western Australia. It occurs from Coral Bay (near North West Cape) south to Groper Bluff (west of Bremer Bay) in depths of 9–106 m where it is caught as by-catch of local gillnet, longline, rock lobster and recreational fisheries. It is sympatric with two other commercial wobbegong species, Orectolobus maculatus and O. ornatus, but differs from these and other IndoPacific species in having the combination of a few unbranched dermal lobes, relatively tall dorsal fins, no warty tubercles on the back of adults, and dark brown corrugated saddles without white spots and blotches. Some details of its biology are also provided.

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Specht, RL, und A. Specht. „Species Richness of Sclerophyll (Heathy) Plant Communities in Australia ̵2 the Influence of Overstorey Cover“. Australian Journal of Botany 37, Nr. 4 (1989): 337. http://dx.doi.org/10.1071/bt9890337.

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The species richness (number of vascular-plant species per unit area) of sclerophyll (heathy) plant communities is examined from south-east Queensland to south-west Western Australia. The species richness of communities of heathy open forest, heathy open scrub, dry heathland and wet heathland is consist- ently similar throughout southern Australia and decreases from dry heathland (on laterite, coastal and inland localities) to heathy open forest, heathy open scrub and wet heathland. Investigation of related microcommunities at Cooloola, Stradbroke Island, Ku-ring-gai Chase and Wilsons Promontory indicates that species richness decreases linearly as overstorey cover increases. In post-fire succession on Stradbroke Island heathy woodland and Dark Island heathland, species richness declines linearly as overstorey cover increases during the regeneration of the community. The appli- cation of limiting fertiliser to Stradbroke Island heathy woodland and Dark Island heathland increases the rate of development of overstorey cover, with a simultaneous decrease in species richness. Species richness of the understorey strata of plant communities appears to be inversely related to the rate of development of foliage projective cover in the overstorey. If an environmental or biotic factor inhibits or retards the development of overstorey cover, the understorey increases in species richness. Conversely, if any environmental or biotic factor accelerates the development of overstorey cover, the understorey species show a reduction in species richness.

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Møller Andersen, N. „The coral bugs, genus Halovelia Bergroth (Hemiptera, Veliidae). I. History, classification, and taxonomy of species except the H. malaya-group“. Insect Systematics & Evolution 20, Nr. 1 (1989): 75–120. http://dx.doi.org/10.1163/187631289x00519.

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AbstractMarine bugs of the genus Halovelia Bergroth inhabit intertidal coral reefs and rocky coasts along the continents and larger islands bordering the Red Sea, Indian Ocean, and western Pacific Ocean as well as on island groups and atolls in these areas. A historical review of the study of the genus is presented and different views upon its classification discussed. The genus Halovelia is redescribed together with its type species, H. maritima Bergroth, and four other previously known species. Fifteen new species are described: H. carolinensis sp.n. (Caroline Islands), H. halophila sp.n. (Sumbawa, Sabah), H. corallia sp.n. (Papua New Guinea, Australia: Queensland), H. esakii sp.n. (Solomon Islands, Irian New Guinea, Moluccas, Sulawesi, Sumbawa, Palau Islands, Philippines), H. polhemi sp.n. (Australia: Northern Territory), H. solomon sp.n. (Solomon Islands), H. novoguinensis sp.n. (Papua New Guinea), H. fosteri sp.n. (Fiji Islands), H. tongaensis sp.n. (Tonga Islands), H. heron sp.n. (Australia: S. Queensland), H. fijiensis sp.n. (Fiji Islands), H. inflexa sp.n. (Sudan, Red Sea), H. annemariae sp.n. (Solomon Islands, Papua New Guinea), H. lannae sp.n. (Java, Singapore, West Malaysia, Sabah, Philippines), and H. wallacei sp.n. (Sulawesi, Sumbawa). Two names are synonymized: H. marianarum Usinger syn.n. (= H. bergrothi Esaki) and H. danae Herring syn.n. (= H. bergrothi Esaki). The following species are removed from the genus Halovelia: H. papuensis Esaki, H. loyaltiensis China, and H. (Colpovelia) angulana Polhemus. A key to the species is included. The taxonomy of the H. malaya-group will be presented in Part II of this work together with the cladistics, ecology, biology, and biogeography of the genus.

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Goldsworthy, SD, PD Shaughnessy, AI Mackay, F. Bailleul, D. Holman, AD Lowther, B. Page et al. „Assessment of the status and trends in abundance of a coastal pinniped, the Australian sea lion Neophoca cinerea“. Endangered Species Research 44 (22.04.2021): 421–37. http://dx.doi.org/10.3354/esr01118.

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Australian sea lions Neophoca cinerea are endemic to Australia, with their contemporary distribution restricted to South Australia (SA) and Western Australia (WA). Monitoring of the species has proved challenging due to prolonged breeding events that occur non-annually and asynchronously across their range. The most recent available data from 80 extant breeding sites (48 in SA, 32 in WA) enabled us to estimate the species-wide pup abundance to be 2739, with 82% (2246) in SA and 18% (493) in WA, mostly based on surveys conducted between 2014 and 2019. We evaluated 1776 individual site-surveys undertaken between 1970 and 2019 and identified admissible time-series data from 30 breeding sites, which revealed that pup abundance declined on average by 2.0% yr-1 (range 9.9% decline to 1.7% growth yr-1). The overall reduction in pup abundance over 3 generations (42.3 yr) was estimated to be 64%, with over 98% of Monte Carlo simulations producing a decline >50% over a 3-generation period, providing strong evidence that the species meets IUCN ‘Endangered’ criteria (decline ≥50% and ≤80%). The population is much smaller than previously estimated and is declining. There is a strong cline in regional abundances (increasing from west to east), with marked within-region heterogeneity in breeding site pup abundances and trends. Results from this study should improve consistency in the assessment of the species and create greater certainty among stakeholders about its conservation status. To facilitate species management and recovery, we prioritise key data gaps and identify factors to improve population monitoring.

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Galeotti, David M., Mark A. Castalanelli, David M. Groth, Clint McCullough und Mark Lund. „Genotypic and morphological variation between Galaxiella nigrostriata (Galaxiidae) populations: implications for conservation“. Marine and Freshwater Research 66, Nr. 2 (2015): 187. http://dx.doi.org/10.1071/mf13289.

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Galaxiella nigrostriata is a freshwater fish that is endemic to the seasonally dry coastal wetlands of south-west Western Australia and considered by the International Union for Conservation of Nature (IUCN) as lower risk–near threatened. This small fish (maximum total length<50mm) aestivates in the sediment over the long, dry Mediterranean summer and its dispersal is limited by lack of habitat connectivity. The objective of this study was to identify the historical and contemporary genetic connectivity between populations of G. nigrostriata and to assess morphological variation between these populations. Results showed that all populations were genetically divergent and no mtDNA haplotypes were shared between populations. In contrast, morphological differentiation between individual populations was weak; however, pooling populations into two broad regions (Swan coastal plain and southern coast) resulted in clear morphological differentiation between these two groups. Based on these results, we postulate G. nigrostriata distribution last expanded in the early Pleistocene ~5.1 million years ago and have since been restricted to remnant wetlands in the immediate area. Galaxiella nigrostriata populations at the northern end of their range are small and are the most vulnerable to extinction. Conservation efforts are therefore required to ensure the survival of these genetically and morphologically distinctive Swan coastal plain populations.

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Potter, Abbey, Michael D. A. Lindsay und John S. MacKenzie. „Ross River virus - at the interface between humans, animals and the environment“. Microbiology Australia 33, Nr. 4 (2012): 160. http://dx.doi.org/10.1071/ma12160.

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Ross River virus (RRV) is the most common cause of mosquito-borne illness in Western Australians. The virus is maintained in nature principally via transmission between competent mosquito vectors and native (marsupial) vertebrate hosts, although humans are suspected of being amplifiers of RRV in some situations. The influence of prevailing environmental conditions on the ecology of RRV has been extensively documented. Indeed, monitoring of environmental variables, together with vector mosquito populations and infection rates with RRV, now provides effective early warning of elevated levels of RRV activity in several different regions of Australia. Serosurveys provide convincing evidence that western grey kangaroos (WGK; Macropus fuliginosus) are commonly infected with the virus in south-west coastal regions of Western Australia. There is also evidence of seroconversions in WGKs coinciding with outbreaks of human disease. Such outbreaks have been preceded by favourable environmental conditions for breeding of WGKs, presumably leading to an increase in numbers of non-immune individuals in the environment. More recently, GIS analyses of clusters of human cases of RRV has shown a relationship between proximity of residence to mosquito and WGK habitat and risk of RRV disease. These findings indicate that monitoring of seroprevalence to RRV in vertebrate hosts of RRV, such as the WGK, may assist in predicting outbreaks of RRV disease and for determining whether strategies to manage natural host populations in close proximity to human habitation may be worth further consideration.

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PETERSON, MAGNUS. „Clarification of the type-locality of Nascio chydaea Olliff (Coleoptera: Buprestidae: Nascionini), with further notes on its biology, distribution and relationships“. Journal of Insect Biodiversity 8, Nr. 2 (13.11.2018): 35–42. http://dx.doi.org/10.12976/jib/2018.08.2.2.

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The precise type-locality of the infrequently encountered Western Australian species Nascio chydaea Olliff, 1886 is redefined from 28˚44ʹS, 116˚24ʹE to 34˚11ʹS, 118˚19ʹE, and thus George Masters is identified as the original collector and January–February 1869 as the date of collection of its lectotype and paralectotype. The first larval and adult hostplant records, Eucalyptus wandoo and an unidentified Asteraceae species respectively, as well as three further distributional records from south-west Western Australia, are provided for N. chydaea and discussed. A colour photograph of its dorsal habitus is also provided, as well as a distribution map for this species. Relationships, general zoogeography and biology of all Nascio species are briefly discussed.

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Griffin, David A., John L. Wilkin, Chris F. Chubb, Alan F. Pearce und Nick Caputi. „Ocean currents and the larval phase of Australian western rock lobster, Panulirus cygnus“. Marine and Freshwater Research 52, Nr. 8 (2001): 1187. http://dx.doi.org/10.1071/mf01181.

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The return of Panulirus cygnus larvae to the coast of Western Australia after nearly a year at sea and its modulation by ocean currents were addressed with an individual-based larval-transport model. The simulations implied that offshore wind-driven transport of larvae is balanced by onshore geostrophic flow. Additional simulations revealed that vertical migration behaviour was essential to larval survival through its impact on advection. The six years simulated include two of high, two of low, and two of average puerulus settlement. The most robust interannual difference of the simulations was that, when coastal sea level was low and the Leeuwin Current was weak, more early-stage larvae were lost to the north and west under the influence of the wind. Conversely, many late-stage model larvae were carried south of the fishery in years when the Leeuwin Current was strong. The fraction of model larvae remaining or arriving offshore of the fishery and metamorphosing was essentially constant from year to year, so the variation in observed puerulus settlement was not explained by the model. The results imply that the nonadvective effects of fluctuations in the Leeuwin (e.g., on temperature and primary production) were primarily responsible for the high variation in natural settlement.

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England, Phillip R., Julia Phillips, Jason R. Waring, Graham Symonds und Russell Babcock. „Modelling wave-induced disturbance in highly biodiverse marine macroalgal communities: support for the intermediate disturbance hypothesis“. Marine and Freshwater Research 59, Nr. 6 (2008): 515. http://dx.doi.org/10.1071/mf07224.

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As biodiversity declines globally, it is becoming increasingly important to understand the processes that create and maintain biodiverse communities. We examined whether the extraordinarily high species diversity of macroalgal communities in shallow coastal waters off south-west Western Australia is related to wave-induced physical disturbance. We used the numerical wave model SWAN to estimate the hydrodynamic forces generated by waves in bathymetrically complex coastal reefs. Oscillatory water motion at the seabed during extreme wave events was used as an index of physical disturbance in macroalgal communities. There was a significant curvilinear relationship between species diversity and disturbance index, consistent with the intermediate disturbance hypothesis (IDH). Diversity was lower at exposed offshore sites where disturbance is likely to be highest and at very sheltered sites with the least disturbance. Our results match those from some other highly diverse habitats, including rainforests, grasslands and coral reefs in which patchy, stochastic disturbance regimes have been hypothesised to prevent the development of homogeneous climax communities, promoting spatiotemporal heterogeneity and increasing total system diversity. Our results represent important evidence in support of a role for the IDH in driving diversity in marine plant communities.

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