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A new species of drilliine turrid is described in the genus Splendrillia from the Gulf of Carpentaria Queensland, Australia. It is compared with S. aurora (Thiele 1925) from Sumatra, Indonesia and two Australian turrids “Crassispira” duplaris (Hedley 1922) and Splendrillia eburnea (Hedley, 1922). Additional information is provided on two species of Splendrillia, S. gratiosa (Sowerby, 1896) and S. bednalli (Sowerby, 1896). S. gratiosa is redescribed and compared with S. hansenae Wells, 1990. The known range of S. bednalli is extended to the south coast of Western Australia.

Seagrass (mainly Enhalus acoroides, Syringodium isoetifolium, Cymodocea serrulata, Thalassia hemprichii and Cymodocea rotundata) gross productivity, determined by a lacunal gas technique, ranged from 0.5-4.3 g C m. In comparison, gross community productivity ranged from 4-9 g C md. Macroalgae, epibenthic and epiphytic algae made the major contribution to gross primary production in the communities studied, contributing 40-90% of gross primary production. Most of the primary production was utilized by hydrolytic and fermentative bacteria and was ultimately oxidized by sulphate-reducing bacteria. Hydrolytic (aerobic) and fermentative bacterial productivity ranged from 3-13 g C md (integrated over a depth of 12 cm in the sediment). Highest rates of sulphate reduction coincided with the below-ground distribution of seagreass roots and rhizomes. Between 1.7-2.2 g C md was oxidized to CO by the sulphate-reducing bacteria, is equivalent to 30-80% of the net community productivity. -from Authors

Associations are established between the southern oscillation index (SOI) and penaeid prawn catches within the northern Australian prawn fishery. Analysis involved calculation of correlations between Gulf of Carpentaria banana prawn andtiger prawn catches and Troup’s SOI. Significant positive correlations are observed between catch size and SOI for specific months from pre-wet to post-wet seasons. For banana prawns, the results indirectly confirm some earlier observations of increased catches in conjunction with high rainfall during the onset of monsoon periods, but also indicate an association with late rains. However, the relationship with tiger prawns appears to be in the opposite direction, showing negative correlations with SOI for particular months. Some hypotheses are suggested to explain these results in terms of environmental effects on spawning populations, and comment is made on the potential for forecasting catch sizes.

A literary criticism of the book "Carpentaria," by Alexis Wright is presented. It discusses the representation of indigenous knowledge in the novel. It outlines the characters and explores the symbolic significance of these characters. It examines the themes of the novel, including the dreamtime mythology as an alternative form of scientific discourse. An overview of the story of the novel is also given.

Malalophus jensenae n. g., n. sp. is described from the gills of the ornate eagle ray Aetomylaeus vespertilio (Bleeker) collected off the eastern coast of the Gulf of Carpentaria, northern Queensland. The new genus is similar to Heliocotyle Neifar, Euzet & Ben Hassine, 1999, with which it shares a haptor bearing seven peripheral loculi and a single dorsal haptoral accessory structure. M.jensenae can be distinguished from species of Heliocotyle by the presence of numerous sclerotised sinuous ridges covering the ventral surfaces of the peripheral loculi of the haptor. It also lacks pseudosepta which are present on the haptor of Heliocotyle species. This is the first published record of a monogenean from an elasmobranch in the Gulf of Carpentaria, Australia.

Environmental evolution of the Gulf of Carpentaria region, the world's largest tropical epicontinental seaway, through the last glacial cycle has been determined from a series of six sediment cores. These cores form the focus of a multi-disciplinary study to elucidate sea level, climate and environmental change in the region. The sedimentary record reveals a series of facies including open shallow marine, marginal marine, estuarine, lacustrine and subaerial exposure, throughout the extent of the basin during this period. The partial or complete closure of the central basin from marine waters results from sea level falling below the height of one or both of the sills that border the Gulf—the Arafura Sill to the west (53 m below present sea level (bpsl)) and Torres Strait to the east (12 m bpsl). The extent and timing of these closures, and restriction of the shallow waterbody within, are intrinsic to local ocean circulation, available latent heat transport and the movement of people and animals between Australia and New Guinea. Whilst the occurrence of the palaeo-Lake Carpentaria has previously been identified, this study expands on the hydrological conditions of the lacustrine phases and extends the record through the Last Interglacial, detailing the previous sea-level highstand (MIS 5.5) and subsequent retreat. When sea levels were low during the MIS 6 glacial period, the Gulf was largely subaerially exposed and traversed by meandering rivers. The MIS 5 transgression (∼130 ka BP) led to marine then alternating marine/estuarine conditions through to MIS 4 (∼70 ka BP) when a protracted lacustrine phase, of varying salinity and depth/area, and including periods of near desiccation, persisted until about 12.2 cal ka BP. The lake expanded to near maximum size (∼190 000 km 2 ) following the intensification/restoration of the Australian monsoon at 14 ka BP. This lake-full phase was short-lived, as by 12.2 cal ka BP, marine waters were entering the basin, coincident with the progressive sea-level rise. Fully marine conditions were restored by about 10.5 cal ka BP by westward connection to the Arafura Sea (Indian Ocean), whereas connections to the Pacific Ocean (Coral Sea) did not occur until about 8 cal ka BP.

The Gulf of Carpentaria in northern Australia has a weather-driven annual periodic amplitude in sea surface height of ~ 0.4 m. Such a signal generates a mass variation that is readily detected by the GRACE mission. We used this naturally occurring phenomenon over a region of ~ 2.6 × 10 5 km 2 to evaluate the accuracy of the GRACE estimates of temporal mass variation. Comparison of the Groupe de Recherche de Geodesie Spatiale 10-day GRACE solutions and observations from a nearby tide gauge show a correlation of 0.93, indicating that the GRGS GRACE solutions capture well the regional signal. On the other hand, the MOG2D-G barotropic model accounts for only ~ 50% of the non-gravitational annual signal, suggesting either deficiencies in the model or that some other non-barotropic process is occurring.

The new species Mallacoota misool is described from the West Macleur Gulf, West Papua. Mallacoota misool sp. nov. is exceptionally similar to the geographically close M. chandaniae Lowry & Springthorpe, 2005 known from the Gulf of Carpentaria in northern Australia and also reported from the South China Sea. Both species have a massive gnathopod 2 propodus defined by two large teeth. Mallacoota misool sp. nov. has the palm medial surface without a dense bunch of seta, which is present in M. chandaniae .

Context Following centuries of intense human exploitation, the global stocks of hawksbill turtle have decreased precipitously and the species is currently considered Critically Endangered by the IUCN. Australia supports the largest breeding aggregations worldwide; however, there are no accurate estimates of population abundance and seasonality for hawksbill turtles at important nesting grounds in eastern Arnhem Land. Aims This study was designed to fill in this lack of ecological information and assist with the conservation and management of hawksbill turtles. More specifically, our overarching goals were to assess nesting seasonality, habitat preferences and provide the first estimate of annual nesting population size at a Northern Territory rookery. Methods In 2009 and 2010 we collected beach monitoring, satellite telemetry and sand temperature data over two nesting seasons at a group of three islands located 30 km off Groote Eylandt in the Gulf of Carpentaria, northern Australia. We subsequently analysed these data to unravel hawksbill nesting behaviour and reproductive outputs, and examined the vulnerability of this rookery to climate change. Key results Hawksbill turtle nesting seasonality consistently started in mid-May, peaked in mid-August and ended in late November. Annual nesting abundance showed a near 3-fold increase between 2009 and 2010, with an average of 220 and 580 hawksbill females nesting on this island group respectively. Sand temperature at 50 cm reached more than 30°C at all monitored sites during most of the peak of the incubation period. Conclusions This remote and untouched group of islands constitutes a major hawksbill turtle rookery both nationally and globally. While anthropogenic impacts and predation are low year round, climate change threatens to skew hatchling sex ratios, eventually leading to an increase in hatchling mortality. Implications Additional ground-based surveys are required to refine the accuracy of population estimates presented in this study. Given the paucity of data in the region, we recommend this island group off Groote Eylandt be used as a population-monitoring index site for the eastern Arnhem Land hawksbill turtle breeding aggregation.

Despite being critically endangered, the at-sea behaviour of hawksbill turtles (Eretmochelys imbricata) remains insufficiently understood to support a global conservation strategy. Habitat location and spatial use are poorly documented, which is particularly true for the globally important Australian hawksbill population. We equipped 10 adult female hawksbill turtles nesting on Groote Eylandt, northern Australia, with Fastloc GPS and Argos satellite transmitters. We quantified fine-scale habitat use and area-restricted search behaviour, and located potential feeding and developmental habitats by simulating hatchling turtle dispersal patterns by using a particle-tracking hydrological model. During the breeding season, females mostly remained near their nesting site. Post-breeding, all turtles migrated to foraging sites on the Australian continental shelf, primarily in the Gulf of Carpentaria in coastal seagrass pastures, but also offshore near coral-reef platforms. The distribution of adult foraging grounds was similar to simulated dispersal patterns of hatchling turtles from distant rookeries, thus highlighting the ecological significance of the Gulf of Carpentaria for hawksbill turtles. Although this hawksbill turtle population is likely to be endemic to Australian waters, national and international conservation initiatives are required to mitigate sources of anthropogenic mortality (e.g. illegal tortoise-shell trade, incidental captures in fishing gear, marine debris, seabed mining exploitation).

Australia has diverse wetlands with multiple threats. We reviewed knowledge about the extent of wetlands, representativeness, impacts and threats to integrity and options for effective conservation. Natural Australian wetlands cover an estimated 33 266 245 ha (4.4%), with 55% palustrine (floodplains and swamps), followed by 31% lakes, 10% estuarine systems, and 5% rivers and creeks. The Lake Eyre (1.1%), Murray–Darling (0.73%), Tanami–Timor Sea Coast (0.71%) and the Carpentaria Coast (0.55%) drainage divisions have more wetlands, also reflected in the distributions among states and territories. Ramsar sites and wetlands in protected areas were generally biased towards the southern continent. Overall representation of mapped wetlands was good for lacustrine (40.6%) and estuarine (34.4%), fair for riverine (16.8%), but inadequate for palustrine (10.8%) wetlands. Within drainage divisions, representation varied considerably, with shortfalls from the Aichi target of 17%. Agriculture, urbanisation, pollution and invasive species have degraded or destroyed wetlands, particularly in the developed south-east, south-west and north-east of the continent. Water resource developments, primarily the building of dams, diversion of water and development of floodplains, seriously threaten Australian wetlands, with all threats exacerbated by climate change impacts of rising sea levels and high temperatures. Management and policy for wetlands is dependent on data on distribution, type and extent of wetlands, a key national constraint. Some States are well advanced (e.g. Queensland) and others lack any comprehensive data on the distribution of wetlands. Mitigation of increasing development (e.g. northern Australia) will be critical for conservation, along with increased representativeness in protected areas and restoration, particularly with environmental flows.

In the Embley River, Gulf of Carpentaria, Australia, the largest catches of the commercially important banana prawns, Penaeus merguiensis , were made on mangrove-lined, steeply sloping mud banks. The upstream limit of distribution of P. merguiensis was found to coincide with the distribution of broad bands of fringing mangrove forests but, except in the wet season, was not related to salinity levels. Although some postlarval P. merguiensis settled on all habitat types in the estuary, large catches were only taken on the mangrove-lined banks. Catches of both postlarvae and juveniles in the upstream reaches of a small creek were almost five times higher than those in the river near the creek mouth. Moreover, prawns in the 2 to 4 mm carapace length (CL) size class were poorly represented in the river but were abundant in catches in the small creek. This suggests that either the survival rate of postlarvae is highest in the upper reaches of the small creeks, or that the small prawns are migrating from the main river into the creek. As prawns increase in size above 5 mm CL it appears that they take part in daily tidal migrations from small creeks to the river and begin a gradual migration from the creeks to the river.

The demersal fish fauna of Albatross Bay, in the eastern Gulf of Carpentaria, northern Australia, was sampled on seven cruises from August 1986 to November 1988, using a random stratified trawl survey. Four depth zones between 7 and 45 m were sampled during both day and night. The mean biomass of fish from all seven cruises was 297 kg ha−1 for days trawls and 128 kg ha−1 for night trawls. The overall mean catch rates were 922 kg h−1 for day trawls and 412 kg h−1 for night trawls. There were marked differences between cruises in both the biomass and catch rate. Approx 890 000 fish of 237 species were collected. Of these, 25 species comprised 82% of the total biomass and 74% of the overall catch rate. The dominant families were Leiognathidae, Haemulidae and Clupeidae, with Sciaenidae and Dasyatidae important at night.Leiognathus bindus was the most abundant species. Twenty-five species occurred in more than 50% of trawls, withCaranx bucculentus the most frequently caught (96% of all trawls). Thirty four species were predators on prawns; their absolute mean biomass was 50 kg ha−1 during the day and 39 kg ha−1 at night. The corresponding catch rates were 171 and 125 kg h−1. Multiple-regression analyses were used to discriminate the effects of diel, seasonal, depth and cruise patterns. Of the 31 most abundant species, 15 showed diel patterns of abundance; 11 species showed seasonal patterns of abundance; 23 species had differential depth distribution; and 13 species showed significant cruise-to-cruise variation in abundance. Cruise variations in abundance were tested against salinity, temperature, tidal exchange, plankton biomass and prawn abundances as well as periods (and lags) of total rainfall prior to sampling. Only total rainfall showed any significant correlation. Total rainfall over a period of 6 wk immediately prior to sampling showed significant positive correlations with the abundances of five species, with overall daytime catch rates, and with the suite of 34 prawn predators. Rainfall and river runoff into Albatross Bay were significantly correlated. In Albatross Bay, the complex of factors affecting fish abundances and the magnitude of between-cruise differences indicate that such tropical communities may be unpredictable and are not seasonally constant. The high catch rates in Albatross Bay relative to similar tropical areas elsewhere are discussed and attributed to the light exploitation of the Albatross Bay stocks. Other than a prawn fishery, there is no commercial trawling in Albatross Bay. Hence, the only fishing mortality is a result of by-catch from prawn trawling. The annual total of such fish by-catch is probably less than 10% of the estimated standing stock of 93 000 tonnes.

Copepods from the Gulf of Carpentaria, the tropical, northern Australian waters adjacent to the Arafura Sea, were collected from 23 sites spanning the entire Gulf during 10 cruises in the period August 1975 to May 1977. Samples were taken using plankton nets with mesh size of 142 μm. One hundred and two species of copepods were identified, 68 species belonging to the sub-order Calanoida, 30 to the Cyclopoida and four to the Harpacticoida. Thirteen of these species were new to science; descriptions of seven have so far been published. Ninety five of the species collected in this study are new records for the Gulf region, and 23 are new records for waters of the Australian continent. The faunal composition is characteristically warm water neritic, and shows similarity to that of Southeast Asia, having at least 88 species in common. Comparisons of copepod species records from the Gulf of Carpentaria with those from the northeastern Pacific coast of Australia (Great Barrier Reef and Moreton Bay) show 79 species to be common to these areas. Of all the species collected in the Gulf, three have been previously recorded from the Indian Ocean but not the Pacific, and five are otherwise only known from the Pacific Ocean. The Gulf is regarded as forming the southeasternmost region of the Indo-pacific marine domain, within which most of the 13 new species encountered in this study appear to be endemic. Species distribution patterns are discussed in relation to post-glacial and present-day hydrodynamics of the region.

Plant and bacterial productivities were compared at different seasons in 3 communities of seagrass in the Gulf of Carpentaria. Australia, in 1985. Seagrass biomass and shoot density were very variable, with no seasonal trend. The gross primary productivity of the seagrasses in each of the communities (Syringodium isoetifoliurn with Cymodocea serrulata in a bay, Halodule uninervis at a river mouth, and Thalassia hernprichii with Cymodocea rotundata on a reef flat) were determined seasonally from rates of lacuna1 gas production. Productivity varied seasonally, being lowest in winter (July). Values ranged from 0.6 to 1.0 g C m-2 d-' for C. serrulata, 0.3 to 8.1 for S. isoetifolium, 0 9 to 3.5 for H. uninervis, 0.2 to 0.4 for T henlprichii and 0.1 to 1.0 for C. rotundata. Gross community primary productivity, measured from diurnal changes in oxygen concentration in the water column, ranged from 3.3 in winter to 9.3 g C m-2 d-' in summer at the bay site, 2.7 to 4 at the river mouth and 3.3 to 8.4 on the reef flat. Bacterial productivity was determined using the rate of tritiated thymidine incorporation into DNA. Most (90 to 95 %) bacterial biomass was produced in the sediment. Between winter and summer, total bacterial productivity (including water column) ranged from 1.0 to 4.8 g C m-2 d-I in the bay, 0.6 to 2.5 at the river mouth and 0.6 to 3.7 on the reef flat. Bacterial productivity averaged 43 O/ O (range 10 to 90 %) of gross primary productivity, and thus would account for about half of the primary production if their growth efficiency were 50 %. Animals appeared to have an impact on bacteria at the sediment surface in summer, when specific growth rates and productivity were high, but numbers were low.

International audience; Cluster analyses (R- and Q-mode) were applied to upper Quaternary coccolith assemblages in a sediment core (MD972132) collected in the Gulf of Carpentaria, northern Australia. This shallow gulf is influenced by the Australian monsoon, is tectonally stable and represents an important link between marine and terrestrial palaeoenvironments. The Gulf of Carpentaria is linked to the Pacific Ocean to the east by Torres Strait (12 m water depth) and to the Indian Ocean to the west by the Arafura Sill (53 m water depth), and therefore has been separated from both oceans during sea-level low-stands, resulting in the formation of Lake Carpentaria. Coccolith assemblages in the gulf are similar to modem assemblages in the region, and correspond to typical assemblages in marginal seas. The cluster analysis defines six species assemblages (R-mode), and six groups of samples (i.e., defined by depth in core depth; Q-mode), some with sub-groups, which were deposited under similar environmental conditions. We thus recognised, four major environmental facies over the past 125 ka, corresponding to closed Lake Carpentaria stages, the transitional periods while active channels sporadically connected Lake Carpentaria to the Indian Ocean, and the opening of the Gulf of Carpentaria to the ocean over either one, or both of the sills. Lake Carpentaria was isolated from both oceans through Marine Isotope Stages (MIS) 5d, MIS 4 and MIS 2, and the Gulf of Carpentaria was connected to both oceans during MIS 5c and MIS 1. Torres Strait was emergent during MIS 5b, was flooded again during MIS 5a and persisted as land bridge from MIS 4 to MIS 1. The Arafura Sill was opened from MIS 5c to MIS 5a and episodically connected the Gulf to the Indian Ocean during MIS 3. (c) 2007 Elsevier B.V. All rights reserved.

Two new species of Stephanotheca are described from the southeast Gulf of Carpentaria, northern Australia, providing the first tropical records of this genus. Stephanotheca ipsum n. sp. is provisionally placed in the genus on the basis of a low ridge of calcification around the edge of the ooecium, which differs from the fully pseudoporous ooecium of Calyptotheca (Lanceoporidae) and resembles the ‘crowned’ ooecium of Stephanotheca , with a central porous area surrounded by a nodular imperforate area. Stephanotheca ipsum and Stephanotheca romajoyae n. sp. are the only species in the genus with more than one avicularium on some zooids. The latter species is distinguished by high variability in avicularium size, shape, position and orientation; it also shares dimorphic avicularia with S. ochracea (Hincks) and is the only species in which they sometimes occur together on the same zooid. This study increases the number of Australian Stephanotheca species to four. The Australian species all have smaller primary orifices and variations in ovicell morphology compared with other, all European, species. In S. ipsum n. sp. the ooecia are ridged, those of S. victoriensis Reverter-Gil et al . have a single row of pseudopores forming an arch, and those of S. ambita (Waters) and S. romajoyae n. sp. have a relatively large pseudoporous area and smaller, lower nodular imperforate area. None of the Australian species have vicarious avicularia, which are known only from the type species, S. barrosoi Reverter-Gil et al .

We assayed mtDNA haplotype [300 base pairs (bp) control region] geography and genealogy in the Indo-Pacific tasselfish, Polynemus sheridani from its contiguous estuarine distribution across northern Australia (n = 169). Eight estuaries were sampled from three oceanographic regions (Timor Sea, Gulf of Carpentaria and the Coral Sea) to assess the impact of Pleistocene sea level changes on the historical connectivity among P. sheridani populations. Specifically, we investigated the genetic consequences of disruption to Indian-Pacific Ocean connectivity brought about by the closure of the Torres Strait. Overall there was significant population subdivision among estuaries (FST = 0.161, PhiST = 0.187). Despite a linear distribution, P. sheridani did not show isolation by distance over the entire sampled range because of genetic similarity of estuaries greater than 3000 km apart. However, significant isolation by distance was detected between estuaries separated by less than 3000 km of coastline. Unlike many genetic studies of Indo-Pacific marine species, there was no evidence for an historical division between eastern and western populations. Instead, phylogeographical patterns were dominated by a starlike intraspecific phylogeny coupled with evidence for population expansion in both the Gulf of Carpentaria and the Coral Sea but not the Timor Sea. This was interpreted as evidence for recent west to east recolonization across of northern Australia following the last postglacial marine advance. We argue that although sufficient time has elapsed postcolonization for populations to approach gene flow-drift equilibrium over smaller spatial scales (3000 km), the signal of historical colonization persists to obscure the expected equilibrium pattern of isolation by distance over large spatial scales (3000 km).

The Carpentaria Conductivity Anomaly of western Queensland is a major element in the electrical conductivity structure of the Australian continent. Investigation of it is significant both for its own sake, and as a case history in the general understanding of continental conductivity structure. Following its earlier discovery by reconnaissance magnetometers arrays, detailed magnetotelluric observations were carried out in 1997 along a transect crossing the anomaly between Cloncurry and Julia Creek. The magnetotelluric results define a good conductor within the crust beneath the sediments of the Eromanga Basin. The conductor extends over a depth range of tens of kilometres. This structure, evidently shown also by aeromagnetic and gravity data, is interpreted as the eastern boundary of the Mt Isa Block at a plate suture, which was later covered by the sediments of the Eromanga Basin. Seismic tomographic results show a major gradient in seismic-wave speed in the region. It appears the potential-field, electromagnetic and seismic methods have detected different characteristics of the same geologic structure, with complementary results. The electromagnetic results, new to this paper, define horizontal position well, and give evidence of highly conducting material from the crust to a depth of tens of kilometres. The seismic results extend the depth of the boundary into the upper mantle. The case history supports the hypothesis that the major conductivity anomalies of the geomagnetic deep-sounding method mark continental sutures of fundamental significance in recording the creation of continents.

Although subsampling is a common method for describing the composition of large and diverse trawl catches, the accuracy of these techniques is often unknown. We determined the sampling errors generated from estimating the percentage of the total number of species recorded in catches, as well as the abundance of each species, at each increase in the proportion of the sorted catch. We completely partitioned twenty prawn trawl catches from tropical northern Australia into subsamples of about 10 kg each. All subsamples were then sorted, and species numbers recorded. Catch weights ranged from 71 to 445 kg, and the number of fish species in trawls ranged from 60 to 138, and invertebrate species from 18 to 63. Almost 70% of the species recorded in catches were "rare" in subsamples (less than one individual per 10 kg subsample or less than one in every 389 individuals). A matrix was used to show the increase in the total number of species that were recorded in each catch as the percentage of the sorted catch increased. Simulation modelling showed that sorting small subsamples (about 10% of catch weights) identified about 50% of the total number of species caught in a trawl. Larger subsamples (50% of catch weight on average) identified about 80% of the total species caught in a trawl. The accuracy of estimating the abundance of each species also increased with increasing subsample size. For the "rare" species, sampling error was around 80% after sorting 10% of catch weight and was just less than 50% after 40% of catch weight had been sorted. For the "abundant" species (five or more individuals per 10 kg subsample or five or more in every 389 individuals), sampling error was around 25% after sorting 10% of catch weight, but was reduced to around 10% after 40% of catch weight had been sorted.

A new diagnosis is presented for Calyptotheca Harmer, 1957 and six species are described from the Gulf of Carpentaria: C. wasinensis (Waters, 1913) (type species), C. australis (Haswell, 1880), C. conica Cook, 1965 (with a redescription of the holotype), C. tenuata Harmer, 1957, C. triquetra (Harmer, 1957) and C. lardil n. sp. These are the first records of Bryozoa from the Gulf of Carpentaria, and the first Australian records for C. wasinensis, C. tenuata and C. triquetra. The limit of distribution of three species is extended east to the Gulf of Carpentaria, from Kenya for C. wasinensis, from China for C. tenuata, and from northwestern Australia for C. conica. The number of tropical Calyptotheca species in Australian territorial waters is increased from seven to eleven.

The Gulf of Carpentaria is an epicontinental sea (maximum depth 70 m) between Australia and New Guinea, bordered to the east by Torres Strait (currently 12 m deep) and to the west by the Arafura Sill (53 m below present sea level). Throughout the Quaternary, during times of low sea-level, the Gulf was separated from the open waters of the Indian and Pacific Oceans, forming Lake Carpentaria, an isolation basin, perched above contemporaneous sea-level with outlet channels to the Arafura Sea. A preliminary interpretation is presented of the palaeoenvironments recorded in six sediment cores collected by the IMAGES program in the Gulf of Carpentaria. The longest core (approx. 15 m) spans the past 130 ka and includes a record of sea-level/lake-level changes, with particular complexity between 80 and 40 ka when sea-level repeatedly breached and withdrew from Gulf/Lake Carpentaria. Evidence from biotic remains (foraminifers, ostracods, pollen), sedimentology and geochemistry clearly identifies a final marine transgression at about 9.7 ka (radiocarbon years). Before this transgression, Lake Carpentaria was surrounded by grassland, was near full, and may have had a surface area approaching 600 km×300 km and a depth of about 15 m. The earlier rise in sea-level which accompanied the Marine Isotopic Stage 6/5 transgression at about 130 ka is constrained by sedimentological and biotic evidence and dated by optical- and thermoluminescence and amino acid racemisation methods.

Increasing research in northern Australia continues to expand the known distribution of backed blades. It is now generally accepted that the distribution maps of 20 years ago reflect the distribution of research rather than of the artefacts themselves. The total number of such artefacts known from northern Australia is, however, still very small. During ethnographic fieldwork in the southern Gulf of Carpentaria in August 1989 the author had occasion to visit a public facility 4 km south of Borroloola overlooking the McArthur River. During an early visit a light scatter of artefacts was noticed in an area denuded through vehicle and pedestrian traffic. A cursory examination located two backed blades, one broken bifacial point and one small grindstone fragment in close association. Subsequent visits failed to locate any other artefact of these types.

Objective To investigate probabilities of establishment of screwworm fly throughout the year, for several locations around Australias coastline. Methods A simulation model that predicts the spread and economic impact of an established screwworm fly population was modified to include stochastic survival functions, to investigate the risks of the pest actually establishing in this country. The effects of time of year, climate, vegetation and the number of incoming flies or larvae were investigated for four locations around Australia. Results Analysis of variance identified a dominant three-way interaction between site, time, and the number of introduced flies. These probabilities are graphed. Discussion In southern areas, as exemplified by Fremantle, the cold winters limit survival. A high probability of establishment exists year round in tropical regions, except in areas around the Gulf of Carpentaria and in the Northern Territory where dry weather mid-year would limit survival. Despite these comparatively lower risks, there were no areas or times where reductions in quarantine efforts could be justified.

Terrigenous shelves include both epeiric (epicontinental) platforms and continental shelves, with a mantle of land-derived sediments, as opposed to biogenic and chemical precipitates. Epeiric platforms are broad, shallowly inundated continental areas. Modem examples such as the North Sea, Hudson Bay, and Gulf of Carpentaria are small by comparison with many of their ancient counterparts. Continental shelves are submerged continental margins, dipping very gently from the outer edge of the shore zone to a depth, generally between 300 and 800 ft (100 and 250 m), at which there is an abrupt increase in slope. If the shelf break is not well defined, the shelf is arbitrarily confined to depths shallower than 200 m (650 ft) (Bates and Jackson, 1980). Present-day shelves have a complex depositional and erosional evolution which commenced in the Mesozoic (Swift, 1969).

Introduction In 536-541 AD a short-term and sudden cooling took place in the northern hemisphere which has caught the attention of researchers only quite recently. In 1983, Richard Stothers and Michael Rampino published a list of volcanic eruptions prior to 630 AD known from historical sources (Stothers & Rampino 1983). Their list included a veil of dust or dry fog that darkened the sky for almost a year in 536-537 AD and caused crop failure. Dendrochronologist Mike Baillie found physical evidence of the event studying the tree rings of Irish oak (Baillie 1994). During the last decades, numerous publications (e.g. Randsborg 1997; Axboe 1999; 2001a; 2001b; Baillie 1999; Keys 1999; Gunn 2000; Hoilund Nielsen 2006; Graslund 2008; Graslund & Price 2012; Arrhenius 2013) have discussed the historical significance and impact of the 536-537 event as well as its archaeological manifestations and written sources. The emergence of this new research topic is due to recent advancements in climate reconstructions based on natural science. Having access to much higher-resolution climate records makes it possible to discuss the demographic, economic, and cultural impacts of climate change more precisely (Widgren 2012, 126). The event in question appears clearly in the growth rings of trees in the northern hemisphere, namely in the common oak (Quercus robur) and families of pine (Pinus). Tree rings show abnormally little growth in 536 and the following years. A similar pattern has been found in tree rings from 540 in the southern hemisphere, for example in southern Chile and Argentina (Baillie 1999; 2007; Gunn 2000; Jones 2000; Young 2000 and citations therein). Tree rings of the northern hemisphere show that growth was hampered in two periods. After recovery a new, even sharper drop emerged in 540-541 (D'Arrigo et al. 2001, 240). According to tree rings, extraordinarily cold weather continued in the northern hemisphere until the year 545 (Graslund & Price 2012, 430 and citations therein). Traces of the event can be found in ice cores from Greenland and Antarctica. The earliest studies referred to the high sulphuric acid content of ice deposits in Greenland from around 540 which indicate the volcanic origin of the event (see Stothers & Rampino 1983; Stothers 1999). Later researchers have also found evidence of substantial sulphate deposits in ice layers from Greenland and Antarctica, supporting the notion of volcanic dust (e.g. Traufetter et al. 2004; Larsen et al. 2008; Ferris et al. 2011). Most scientists who have studied the causes of the event of 536 have concluded that it was caused by an immense volcanic eruption in the tropical zone of Earth (see Stothers & Rampino 1983; Stothers 1999; Larsen et al. 2008). Several volcanoes and places have been proposed (see Stothers 1984; Keys 1999; Wohletz 2000). The most convincing evidence so far refers to the Tierra Blanca Joven eruption of the Ilopango caldera in central El Salvador (Dull et al. 2001; 2010; Oppenheimer 2011, 254 ff.). Others believe that a comet or a meteorite explosion caused the event (Baillie 1999; 2007; Rigby et al. 2004). Magnetite and silicate spherules found from the ice layers of 536-537 in Greenland support this alternative explanation (Abbott et al. 2008). Similar sphelures have been found in northern Australia from a supposed metorite crater in the Gulf of Carpentaria (Abbott et al. 2008; Subt et al. 2010). Thus, natural scientists have not agreed on what caused the climate anomaly of 536-537. Nevertheless, according to tree growth rings it was the worst shock to the ecosystem within the last 2000 years (Baillie 2007, 106). Antti Arjava (2006) has studied written evidence from Mediterranean sources of the extraordinary event of 536-537. In several of these sources it appears that a darkening of the sun was observable in the Mediterranean region during more than a year. Bishop Michael the Syrian writes in his 12th century chronicle, quoting the 6th century ecclesiastical historian John of Ephesos: Each day it shone for about four hours, and still this light was only a feeble shadow. …

Glacial cycles during the Pleistocene reduced sea levels and created new land connections in northern Australia, where many currently isolated rivers also became connected via an extensive paleo-lake system, ‘Lake Carpentaria’. However, the most recent period during which populations of freshwater species were connected by gene flow across Lake Carpentaria is debated: various ‘Lake Carpentaria hypotheses’ have been proposed. Here, we used a statistical phylogeographic approach to assess the timing of past population connectivity across the Carpentaria region in the obligate freshwater fish, Glossamia aprion. Results for this species indicate that the most recent period of genetic exchange across the Carpentaria region coincided with the mid- to late Pleistocene, a result shown previously for other freshwater and diadromous species. Based on these findings and published studies for various freshwater, diadromous and marine species, we propose a set of ‘Lake Carpentaria’ hypotheses to explain past population connectivity in aquatic species: (1) strictly freshwater species had widespread gene flow in the mid- to late Pleistocene before the last glacial maximum; (2) marine species were subdivided into eastern and western populations by land during Pleistocene glacial phases; and (3) past connectivity in diadromous species reflects the relative strength of their marine affinity.

A Queensland state-wide review of coastal and inland fish traps and weirs is undertaken. More than 179 sites are described. For coastal Queensland, it is demonstrated that traps with multiple pens are common in the Torres Strait and at a limited number of locations in the southern Gulf of Carpentaria. Most traps and weirs south of Torres Strait and the Gulf are isolated structures, with traps in most cases having a single pen. Walls of traps are most often in the shape of an arc and found at points and estuaries and only occasionally on open beaches. Some traps and weirs on the coast were built or used by non-Indigenous people, including South Sea Islanders. Less information could be located on traps and weirs of inland Queensland, which appear to have included many organic traps and weirs. It was found that weirs are common east of the Great Dividing Range, while traps were common to the west. The review draws heavily on unpublished data and reports held by the Queensland Department of Environment and Resource Management. The use of this information along with published sources, theses, explorer's diaries and ethnographic accounts allows a comprehensive overview of available information. Fish traps in particular are often found in coastal zones subject to development pressure and this work provides a baseline resource to generate discussion about research and management of this significant site type in these zones.