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Three new species of the genus Caridina are described from the northernmost part of Australia. Caridina darwin n. sp. resembles Caridina temasek Choy and Ng, 1991 but differs in the armature of the rostrum, the development of epipods on the pereiopods and the absence of an appendix interna on the male first pleopods. Caridina magnovis n. sp. resembles Caridina serratirostris de Man, 1892 but differs in the armature of the ventral margin of the rostrum, a shorter stylocerite, a stouter carpus of the first pereiopod, the number and size of spiniform setae on the third and fifth pereiopods, the shape of the preanal carina and the size of the embryos (referred to as "eggs" in most previous publications). Caridina wilsoni n. sp. resembles Caridina gracilirostris de Man, 1892 but differs in the size of the embryos and in some length to width ratios of the segments of the pereiopods. Detailed morphological descriptions of all three new species are given. A molecular phylogeny (mt DNA 16S) supports the morphospecies hypothesis and illustrates the phylogenetic relationship with morphologically similar species from outside Australia. [ABSTRACT FROM AUTHOR]

This study detected two potential pathogens, Vibro parahaemolyticus, which causes acute hepatopancreatic necrosis disease (AHPND), and white spot syndrome virus (WSSV), in fishing bait in South Korea. However, their infectious nature was not confirmed, possibly due to the degradation caused by freezing/thawing or prolonged storage under frozen conditions. While infectivity was not confirmed in this study, there is still a significant risk of exposure to these aquatic products. Furthermore, fishing bait and feed should be handled with caution as they are directly exposed to water, increasing the risk of disease transmission. In Australia, cases of WSSV infection caused by imported shrimp intended for human consumption have occurred, highlighting the need for preventive measures. While freezing/thawing is a method for inactivating pathogens, there are still regulatory and realistic issues to be addressed. [ABSTRACT FROM AUTHOR]

Water development threatens rivers and their biodiversity. Amphidromous shrimp are particularly vulnerable as they require migration between freshwater and estuaries to complete their life cycle. The Fitzroy River is a large tropical intermittent river undergoing water development that is home to the amphidromous shrimp Macrobrachium spinipes (cherabin), yet little is known about its habitat use and flow‐ecology making it difficult to inform sustainable water‐take.We investigated habitat associations, distributional patterns suggestive of amphidromy, and the influence of water availability by sampling main channel and floodplain pools along a 350‐km river length during 2 contrasting flow years. Applying a size‐specific abundance model, we estimated abundance per size class, site, and year. We then predicted abundance at the landscape scale with remotely sensed water to reveal the impact of water availability on the meta‐population.Our model revealed that juveniles were in greatest abundance in downstream main channel pools, whereas adults were in greatest abundance in upstream floodplain pools. Abundance varied by year with lower numbers predicted in the low‐flow year. Longitudinal and habitat patterns remained when our pool‐level results were scaled to the landscape, and the positive relationship of abundance to wet‐season flow was strengthened. The predominance of smaller cherabin in the lower reaches of the river provides indirect support for an estuarine nursery and amphidromous life history; however, small individuals observed in landlocked pools, during late dry season suggests possible within‐river recruitment.The importance of water development policies that protect wet‐season flow and passage along the Fitzroy River is supported by this work. These types of policies are likely to be important for this and other amphidromous shrimp species across Australia, Southeast Asia and further afield. Further research detailing the species life history and describing flow–recruitment relationships will be important contributions to understanding this important taxonomic group and refining policies for current and future water resource development. [ABSTRACT FROM AUTHOR]

Fossil spinicaudatan taxonomy heavily relies on carapace features (size, shape, ornamentation) and palaeontologists have greatly refined methods to study and describe carapace variability. Whether carapace features alone are sufficient for distinguishing between species of a single genus has remained untested. In our study, we tested common palaeontological methods on 481 individuals of the extant Australian genus Ozestheria that have been previously assigned to ten species based on genetic analysis. All species are morphologically distinct based on geometric morphometrics (p ≤ 0.001), but they occupy overlapping regions in Ozestheria morphospace. Linear discriminant analysis of Fourier shape coefficients reaches a mean model performance of 93.8% correctly classified individuals over all possible 45 pairwise species comparisons. This can be further increased by combining the size and shape datasets. Nine of the ten examined species are clearly sexually dimorphic but male and female morphologie strongly overlap within species with little influence on model performance. Ornamentation is commonly species-diagnostic; seven ornamentation types are distinguished of which six are species-specific while one is shared by four species. A transformation of main ornamental features (e.g. from punctate to smooth) can occur among closely related species suggesting short evolutionary timescales. Our overall results support the taxonomic value of carapace features, which should also receive greater attention in the taxonomy of extant species. The extensive variation in carapace shape and ornamentation is noteworthy and several species would probably have been assigned to different genera or families if these had been fossils, bearing implications for the systematics of fossil Spinicaudata. [ABSTRACT FROM AUTHOR]

Temporal and spatial closures are often used to manage harvest by trawl fisheries. Trawl closures implemented to benefit a particular species may also benefit other species, but these indirect effects are rarely quantified. Using the New South Wales (Australia) Ocean Trawl Fishery as a case study, the potential unintended effects of trawl closures designed to protect juvenile eastern king prawn were explored for other quota managed Sillaginidae within the fishery (stout whiting Sillago robusta and eastern school whiting Sillago flindersii). Both species of whiting were more abundant within closed areas than adjacent areas, and spawning‐sized stout whiting were proportionally more abundant within closed areas. Thus, closures implemented to protect prawns also provided protection for exploited whiting species, including spawning‐sized individuals, enhancing their overall impact on the fishery. Spatial management of trawl fisheries elsewhere in the world may also similarly benefit other exploited species. [ABSTRACT FROM AUTHOR]

Using length frequency distribution data (LFD) is cost-effective for estimating somatic growth in fish or invertebrates as length data are relatively easy to obtain. The recently developed R packages TropFishR and fishboot extend classic ELEFAN (Electronic LEngth Frequency ANalysis) programs and include more powerful optimization procedures and a bootstrap method for estimating uncertainties. Yet, the fundamental functions require users to provide search conditions (e.g. upper and lower limits for each parameter, length-class size, number of length-classes for the calculation of moving average), which can significantly affect the results. In this paper, we compare the ELEFAN approach with a Bayesian approach in analysing LFD, employing both standard and seasonal von Bertalanffy growth functions. We apply both approaches to a commercially valuable but poorly studied red endeavour prawn (Metapenaeus ensis) harvested in Australia's Northern Prawn Fishery. Sensitivity tests on ELEFAN confirm that any change in search settings would affect the results. Simulation studies on Bayesian growth models show that Linf and K can be accurately obtained even with modal progression of only one year-class and using non-informative priors. However, age information, including the theoretical age at length zero (t0), is difficult to estimate and requires LFD from multiple age classes and informative priors. The Bayesian models yield mean parameters of: Linf = 36.56 mm (carapace length), K = 2.74 yr–1, and t0 = -0.02 yr for the males, and Linf = 51.81 mm, K = 1.94 yr–1, and t0 = -0.02 yr for the females. Seasonal oscillation models fit the LFD better, but the improvement is small and the estimated season-related parameters have large variances. [ABSTRACT FROM AUTHOR]

To begin to understand the impact of food chain dynamics on ciguatera risk, we used published data to model the transfer of ciguatoxins across four trophic levels of a marine food chain in Platypus Bay, Australia. The data to support this first attempt to conceptualize the scale of each trophic transfer step was limited, resulting in broad estimates. The hypothetical scenario we explored generated a low-toxicity 10 kg Spanish mackerel (Scomberomorus commerson) with a flesh concentration of 0.1 µg/kg of Pacific-ciguatoxin-1 (P-CTX-1, also known as CTX1B) from 19.5–78.1 µg of P-CTX-1 equivalents (eq.) that enter the marine food chain from a population of 12–49 million benthic dinoflagellates (Gambierdiscus sp.) producing 1.6 × 10−12 g/cell of the P-CTX-1 precursor, P-CTX-4B. This number of Gambierdiscus could be epiphytic on 22–88 kg of the benthic macroalgae (Cladophora) that carpets the bottom of much of Platypus Bay, with the toxin transferred to an estimated 40,000–160,000 alpheid shrimps in the second trophic level. This large number of shrimps appears unrealistic, but toxic shrimps would likely be consumed by a school of small, blotched javelin fish (Pomadasys maculatus) at the third trophic level, reducing the number of shrimps consumed by each fish. The Spanish mackerel would accumulate a flesh concentration of 0.1 µg/kg P-CTX-1 eq. by preying upon the school of blotched javelin and consuming 3.6–14.4 µg of P-CTX-1 eq. However, published data indicate this burden of toxin could be accumulated by a 10 kg Spanish mackerel from as few as one to three blotched javelin fish, suggesting that much greater amounts of toxin than modelled here must at certain times be produced and transferred through Platypus Bay food chains. This modelling highlights the need for better quantitative estimates of ciguatoxin production, biotransformation, and depuration through marine food chains to improve our understanding and management of ciguatera risk. [ABSTRACT FROM AUTHOR]

Habitat associations can be critical predictors of larger‐scale organism distributions and range shifts. Here the authors consider how a critical habitat, kelp (Ecklonia radiata) and prey (mysid crustacean swarms), can influence small‐ and large‐scale distribution on the iconic common (weedy) seadragon (Phyllopteryx taeniolatus:Syngnathidae). P. taeniolatus are charismatic fish endemic to the temperate reefs of southern Australia, reported to range from Geraldton, Western Australia (28.7667°S, 114.6167°E) around southern Australia to Port Stephens, New South Wales (32.614369°S, 152.325676°E). The authors test a previously developed model of seadragon habitat preferences to predict P. taeniolatus occurrence within four sites from Sydney to the northern limit of their range in eastern Australia. They determined that P. taeniolatus associations with Ecklonia and mysid shrimp can be extrapolated across multiple sites to predict the occurrence of individual P. taeniolatus within a location/site. For instance, the authors demonstrated a significant positive relationship between the density of mysid swarms and the density of P. taeniolatus, evident across all sites despite large differences in the density of mysid swarms among sites. The findings are the first to model P. taeniolatus habitat associations across multiple sites to the northern limit of their range and have applications in protecting P. taeniolatus populations and how they may respond under climate change scenarios, such as poleward kelp retractions. [ABSTRACT FROM AUTHOR]

Macrobrachium australiense, is one of Australia's most widespread freshwater invertebrates. Although a significant amount of research has been conducted to understand the diversity of crustacean species in Australia, there has been considerably less effort focused on their Temnocephalidae symbionts. The present study aims to identify Temnocephalidae species found in M. australiense, along with determining their impacts on the fitness of their hosts. A total of 54 M. australiense (common Australian river prawn) were examined for evidence of infection with Temnocephalidae species, of which 96.3% showed at least one sign of infection with Temnocephalidae. Due to damage and immaturity of the worms collected from, they have been referred to as Temnocephalidae sp. based on the presence of tentacles on the anterior margin of the body, and pedunculate sucker located dorsally on the ventral surface. Possible mechanical damage to gill lamellae resulting from either egg deposition or autolysis is evident. In the phylogenetic tree built based on sequences of the 28S rRNA gene, specimens in the present study grouped separately from other Temnocephalidae species reported from Australia. [ABSTRACT FROM AUTHOR]

The taxonomic history of the atyid shrimp Paratya in Australia has been one of confusion due to the high morphological variability in material collected from its wide range of distribution. Early research concluded that all material should be considered a single species, P. australiensis Kemp, pending an acceptable revision. After morphological examination of material throughout the known distribution, others concluded that only a single species occurred in Australia. Molecular studies have recognised at least 10 distinct lineages. In the current study, fresh material was collected, and molecular sequencing was undertaken from a single leg from each specimen. Having confirmed the 10 lineages, the specimens were dissected for morphological examination. These lineages are recognised as distinct species and morphological descriptions are provided for seven new species: Paratya walkeri n. sp., P. spinosa n. sp., P. williamsi n. sp., P. whitemae n. sp., P. strathbogiensis n.sp., P. gariwerdensis n. sp. and P. rouxi n. sp. A new combination, P. arrostra Riek, is raised from sub-species to species, P. tasmaniensis Riek is reinstated and P. australiensis Kemp is redescribed. A key based on morphology is included. [ABSTRACT FROM AUTHOR]

Penaeus monodon is the primary shrimp species farmed in Australia. Based on an extensive survey of the literature and industry information, we identified and compiled 318 different parameters related to shrimp aquaculture enterprises and production. Using these as input parameters, we performed detailed bioeconomic modelling for evaluating the economic viability of intensive culture scenarios and identified the major drivers of business profitability under Australian conditions. Three business types (hatchery, grow‐out and combined hatchery + grow‐out) were evaluated by simulating varying numbers of female broodstock and ponds in operation based on annual, six‐monthly, quarterly and monthly stocking events per year over a 10‐year period. Net present value was the main economic variable for comparison. The hatchery business was most profitable in scenario with 250 females being spawned monthly or 500 females at least quarterly, that is, >2000 females spawned per year. Feed, acquisition of broodstock and fixed labour were major costs for hatchery scenarios. For a grow‐out business, all scenarios were profitable even at the smallest scale modelled (50 ponds stocked annually). Feed, power and purchase of post‐larvae were major costs for grow‐out business. The combined business was the most profitable for a large enterprise and required at least 100 ponds stocked over the year. The three major costs in the combined business were feed, power and labour. Sensitivity analyses showed feed cost and survival parameters were critical for profitability. [ABSTRACT FROM AUTHOR]

Square-mesh codends (i.e. turned 45 degrees or 'T45′) made from a minimum stretched mesh opening (SMO) of 27-mm mesh hung on the bar are mandated for estuarine-trawl fisheries targeting penaeids (mostly school prawns, Metapenaeus macleayi) in New South Wales, Australia. However, owing to variable mesh shrinkage over time, often slightly larger SMOs are supplied, and sometime too large to be oriented as T45 for the targeted school prawns (>13–15 cm carapace length; CL). During three experiments involving paired trawls with and without codend covers, we sought to investigate if, compared to a conventional 27-mm T45 codend, lateral openings in 30-mm SMO could be appropriately maintained by orientating diamond-shaped ('T0′) meshes at narrow (experiment 1) or normal (experiment 2) circumferences, or turned 90 degrees ('T90′; experiment 3). Analyses of size selection was done after first testing for species-specific cover effects, which required fish sizes to be assessed via a paired-hauls approach while sizes for school prawns were modelled using a covered-codend approach. Compared to the 27-mm T45 codend, only the T0 mesh hung at a normal circumference provided the same size selection for school prawns, with the two other alternative configurations producing wider selection. But, while incidental fish catches were low (14% of total catch), all new codends caught between ∼2 and 7 × more individuals of some small fish cross all sizes, including juveniles of an economically important species (tailor, Pomatomus saltarix). The data reiterate that among the codends tested, T45 mesh is the optimal configuration for regional penaeid trawls in terms of consistently maximining school prawn size selection and the escape of small fish, and so high-quality material in the required sizes needs to be sourced. [ABSTRACT FROM AUTHOR]

Understanding recruitment variability in marine fisheries has benefits for the stock management and dependent fishers' ability to plan their income. Here, we overview past and new research on the complex recruitment dynamics of redleg banana prawns Penaeus indicus in Australia's Joseph Bonaparte Gulf to assess themes dating back to the time of Hjort and identify new challenges. During 2015 and 2016, redleg prawn catches and catch per unit effort decreased to anomalously low levels, suggesting a substantial decrease in prawn biomass. We hypothesized that low catches could be explained by temporary drops in sea level and rainfall potentially reducing the ability of postlarvae to reach their nursery ground. We contend that very bad prawn catch years may be predicted using two variables that are possible drivers of recruitment—the January Southern Oscillation Index and the combined January to February cumulative rainfall. However, due to challenges in verifying and defining such environmental relationships for inclusion in a stock assessment, we propose development of a harvest strategy framework to support management recommendations. Our study highlights the increasing role of anthropogenic climate change in exaggerating the impacts of environmental drivers on recruitment processes and the need to also focus on multidisciplinary research. [ABSTRACT FROM AUTHOR]

The bunyavirus Mourilyan virus (MoV) occurs commonly in Black tiger (Penaeus monodon) and kuruma shrimp (Penaeus japonicus) farmed in eastern Australia. There is circumstantial evidence of MoV causing mortalities among P. japonicus moved from farm ponds to tanks for rearing as broodstock. To directly assess its pathogenic potential, independent cohorts of pond‐ (n = 24) or tank‐reared juvenile (n = 21) P. japonicus were challenged intramuscularly with a cephalothorax tissue homogenate of P. monodon containing high loads of MoV (1.48 ± 0.28 × 108 MoV RNA copies/µg total RNA). In each trial, mortalities accumulated gradually among the saline‐injected controls. Mortality onset occurred 12–14 days earlier in the pond‐reared shrimp, possibly due to them possessing low‐level pre‐existing MoV infections. Despite the time to onset of mortality differing, Kaplan–Meier survival analyses confirmed mortality rates to be significantly higher in both the pond‐ (p =.017) and tank‐reared shrimp (p =.031) challenged with MoV. RT‐qPCR data on shrimp sampled progressively over each trial showed high loads of MoV to establish following challenge and discounted GAV and other endemic viruses from contributing to mortality. Together, the data show that acute MoV infection can adversely compromise the survival of juvenile P. japonicus. [ABSTRACT FROM AUTHOR]

The majority of Australian Spinicaudata Linder, 1945 inhabit the (semi)arid deserts of Australia's lowlands. However, several closely related species of Paralimnadia Sars, 1896 inhabit small temporary habitats throughout the Great Dividing Range in eastern Australia. By combining analyses of mitochondrial cytochrome c oxidase subunit I (COI) with double-digest restriction-site associated DNA (ddRAD) data, we studied the species diversity and genetic diversity of this group of mountain-dwelling branchiopods. Levels of genetic differentiation in COI are relatively low between putative species (mostly between 1.5 and 6.7%), complicating COI-based species delimitation. Depending on the applied threshold, three to six species are inferred in the studied area, with most putative species being geographically restricted. Particularly notable are the high levels of population differentiation indicated by ddRAD analyses between nearby populations within putative species. This suggests that gene flow is limited, even between populations separated only by a few kilometres. This may lead to fast population differentiation, which in turn might drive speciation. Our data suggest that the species diversity of Paralimnadia in the Great Dividing Range is much higher than currently appreciated. Several closely related species of Paralimnadia (Crustacea, Branchiopoda, Spinicaudata) inhabit small temporary habitats throughout the Great Dividing Range in eastern Australia. By combining analyses of mitochondrial COI with double-digest restriction-site associated DNA (ddRAD) data, we studied the species diversity and genetic diversity of this group of mountain-dwelling branchiopods. Our data suggest that the species diversity of Paralimnadia in the Great Dividing Range is much higher than currently appreciated. [ABSTRACT FROM AUTHOR]

Paratya australiensis Kemp (Decapoda: Atyidae) is a widely distributed freshwater shrimp in eastern Australia. The species has been considered as an important stream organism for studying genetics, dispersal, biology, behaviour and evolution in atyids and is a major food source for stream dwelling fishes. Paratya australiensis is a cryptic species complex consisting of nine highly divergent mitochondrial DNA lineages. Previous studies in southeast Queensland showed that ''lineage 4'' favours upstream sites at higher altitudes, with cooler water temperatures. This study aims to identify putative selection and population structure between high elevation and low elevation populations of this lineage at relatively small spatial scales. Sample localities were selected from three streams: Booloumba Creek, Broken Bridge Creek and Obi Obi Creek in the Conondale Range, southeast Queensland. Six sample localities, consisting of 142 individuals in total were sequenced using double digest Restriction Site Associated DNA-sequencing (ddRAD-seq) technique. Among the 142 individuals, 131 individuals shared 213 loci. Outlier analysis on 213 loci showed that 27 loci were putatively under selection between high elevation and low elevation populations. Outlier analysis on individual streams was also done to test for parallel patterns of adaptation, but there was no evidence of a parallel pattern. Population structure was observed using both the 27 outliers and 186 neutral loci and revealed similar population structure in both cases. Therefore, we cannot differentiate between selection and drift here. The highest genetic differentiation was observed between high elevation and low elevation populations of Booloumba Creek, with small levels of differentiation in the other two streams. [ABSTRACT FROM AUTHOR]

In 2011, a male pristiophorid was caught by a prawn trawler north east of Cape Moreton, Queensland, Australia. Molecular analyses confirmed the specimen to be the common sawshark Pristiophorus cirratus. Historical catch data indicate the occurrence of the species in the region but this is the first verified record of P. cirratus occurring in the waters of southern Queensland. Together, these records extend the recognised northern limit of P. cirratus by c. 500 km, which suggests that further investigation of its distribution is warranted. [ABSTRACT FROM AUTHOR]

While prawns are produced domestically, most prawns currently consumed in Australia are imported from Asia. Local producers are concerned that these imports are depressing prices for their product, and future growth in imports due to increased global supplies would reduce their viability. We examined the price integration of prawn products within the Australian market using the autoregressive distributed lag (ARDL) bounds testing method. A Dynamic Inverse Almost Ideal Demand System (IAIDS) was employed to derive own- and cross-price flexibilities and scale flexibilities for the three prawn categories to determine whether the supply of one prawn product had an impact on the price of the other prawn products. The results suggest there is no price integration between domestically produced prawns (wild-caught and aquaculture) and imported prawns, but strong price integration exists between domestically produced prawns. The findings of the demand analysis confirm this result. [ABSTRACT FROM AUTHOR]

Australia banned imports of uncooked prawns from Asia in early 2017 after an outbreak of the deadly white spot disease in southern Queensland. The ban expired after 6 months, and it remains unclear what the source of the epidemic was, or the mechanism through which it may have entered the country. The Queensland State Government offered financial assistance to selected producers, although as a group, producers benefit from the higher prices resulting from the ban. In fact, the major cost of the ban is borne by domestic consumers and foreign producers. The major impact is a transfer from Australian consumers to Australian producers. These transfers are quantified in this analysis, as are the impacts on developing country exporters. [ABSTRACT FROM AUTHOR]

Elemental profiling has emerged as a powerful end-to-end tool for authenticating origins of our food but its adoption by the industry is hindered by analytical delays and inaccessibility due to the laboratory-based nature of most instruments. To address these critiques, we evaluated a handheld x-ray fluorescence (XRF) scanner as a rapid in-situ approach for discerning provenance in a case study of black tiger prawns (Penaeus monodon) across Australia. To better understand the limitations and opportunities of the technology for seafood provenance, we evaluated provenance classes (site, jurisdiction, and production method), preparation method (cooked vs raw), and biological traits (carapace length, body weight, and sex) to disentangle the dominant influences on multivariate elemental fingerprints. Harvest site was found to be the dominant explanatory variable, indicating unique site properties eclipsed jurisdiction and production method (farmed vs wild) contributions. Raw samples were shown to be better suited for provenance determinations due to more pronounced variation in elemental fingerprints between classes. To simulate a real-world application, we constructed and tested machine learning classification models for identification of prawns back to harvest site, jurisdiction, or production method. The models employing raw prawn samples demonstrated high accuracies, with a classification accuracy of 87.5% to site; 98% accuracy to jurisdiction, and 100% accuracy to production method. Our results demonstrate the practicality of this first line of defence technology for provenance on the market floor or in supply chains. This innovative technique could facilitate the adoption of portable elemental profiling for provenance across supply chains, leading to a more sustainable and ethical seafood trade. • Novel elemental technology tested for seafood provenance applications. • Handheld XRF can rapidly produce elemental fingerprints of prawn provenance. • Prawns >80% accurately classified to site, jurisdiction, and production method. • Portability and ease-of-use suggest its suitability for industry applications. [ABSTRACT FROM AUTHOR]

The fundamental geological framework of the concealed Paleoproterozoic East Tennant area of northern Australia is very poorly understood, despite its relatively thin veneer of Phanerozoic cover and its position along-strike from significant Au–Cu–Bi mineralisation of the Tennant Creek mining district within the outcropping Warramunga Province. We present 18 new U–Pb dates, obtained via Sensitive High Resolution Ion Micro Probe (SHRIMP), constraining the geological evolution of predominantly Paleoproterozoic metasedimentary and igneous rocks intersected by 10 stratigraphic holes drilled in the East Tennant area. The oldest rocks identified in the East Tennant area are two metasedimentary units with maximum depositional ages of ca. 1970 Ma and ca. 1895 Ma respectively, plus ca. 1870 Ma metagranitic gneiss. These units, which are unknown in the nearby Murphy Province and outcropping Warramunga Province, underlie widespread metasedimentary rocks of the Alroy Formation, which yield maximum depositional ages of 1873–1864 Ma. While parts of this unit appear to be correlative with the ca. 1860 Ma Warramunga Formation of the Warramunga Province, our data suggest that the bulk of the Alroy Formation in the East Tennant area is slightly older, reflecting widespread sedimentation at ca. 1870 Ma. Throughout the East Tennant area, the Alroy Formation was intruded by voluminous 1854–1845 Ma granites, contemporaneous with similar felsic magmatism in the outcropping Warramunga Province (Tennant Creek Supersuite) and Murphy Province (Nicholson Granite Complex). In contrast with the outcropping Warramunga Province, supracrustal rocks equivalent to the 1845–1810 Ma Ooradidgee Group are rare in the East Tennant area. Detrital zircon data from younger sedimentary successions corroborate seismic evidence that at least some of the thick sedimentary sequences intersected along the southern margin of the recently defined Brunette Downs rift corridor are possible age equivalents of the ca. 1670–1600 Ma Isa Superbasin. Our new results strengthen ca. 1870–1860 Ma stratigraphic and ca. 1850 Ma tectono-magmatic affinities between the East Tennant area, the Murphy Province, and the mineralised Warramunga Province around Tennant Creek, with important implications for mineral prospectivity of the East Tennant area. [ABSTRACT FROM AUTHOR]

Water resource development can lead to the significant alteration of natural flow regimes, which can have impacts on the many aquatic species that rely on both freshwater and estuarine environments to successfully complete their lifecycles. In tropical northern Australia, annual catches of commercially harvested white banana prawns (WBP) are highly variable in response to environmental conditions, namely rainfall and subsequent riverine flow. However, little is known about the spatial extent to which flow from individual rivers influences offshore WBP catch. In this study, we quantify how the relationship between WBP catch in the Gulf of Carpentaria is influenced by flow from the Mitchell River, Queensland Australia. We used a Bayesian framework to model both prawn presence and catch per unit effort, and found evidence that multiple components of the flow regime contribute to fishery catch. We also found evidence to suggest that the relationships between prawn presence and flow were spatially structured across the fishing ground. Our results suggest that attributing fishery catch to a single river remains challenging, though highlights the importance of maintaining natural flow regimes to support a highly valuable commercial fishery species in the face of potential water resource development. • Water resource development threatens natural flow regimes. • We modelled how riverine flow influences a highly valuable prawn fishery. • Multiple aspects of the flow regime were important for fishery catch. • Relationships between catch and flow were spatially structured in the fishery. • Our results inform management of ecosystems threatened by hydrologic development. [ABSTRACT FROM AUTHOR]

This research has explored the potential of stable isotope and trace metal profiles to distinguish Australian prawns from prawns imported from neighbouring Asian countries. Australian prawns were collected mostly from the Brisbane area. Strong differences in Australian vs. imported prawns were evident from both the isotope and trace element data, with the differences most likely occurring because imported prawns are typically reared in aquaculture facilities and frozen prior to sale in Australia. The aquaculture origins are characterised by comparatively; low δH VSMOW , δ 13 C VPDB values, low concentrations of arsenic, zinc and potassium, and high water contents (>80%). Relatively high arsenic and cadmium contents were found within Australian prawns, but the concentrations did not exceed local human health guidelines. [ABSTRACT FROM AUTHOR]

Background: Banana shrimp Fenneropenaeus merguiensis has emerged as an important aquacultured shrimp species in South East Asia and Australia. However, the quantitative genetic basis of economically important traits in this species are currently not available, while for body colour, cooked or uncooked, there are no genetic parameter estimates for any shrimp or indeed any decapod crustacean. In this study, we report for banana shrimp genetic parameters for morphometric traits and, the first time for any shrimp, parameter estimates for body colour. Ten highly polymorphic microsatellite markers were developed from genomic sequences and used to construct a pedigree for 2000 offspring from approximately 60 female and 60 male parents that were sampled from a single routine commercial production pond. Results: Restricted maximum likelihood method applied to a single trait mixed model was used to estimate heritabilities, while correlations were estimated using the multi-trait approach. The estimates of heritability for morphometric traits were moderate to high (h² = 0.14 - 0.50). Body colour of uncooked shrimp showed a heritable additive genetic component (h² = 0.03 - 0.55), and those estimates obtained for cooked shrimp were significantly different from zero. Genetic correlations among morphometric traits were all positive and very high (close to unity, rg = 0.85 - 0.99). The genetic correlations of body traits (weight, length and width) were positive with both colour after cooking (0.74 - 0.84) and body colour measured on live shrimp (0.59 to 0.70). The positive genetic correlations between the cooked body colour and uncooked body colour (0.64 ± 0.20) suggests these two traits can be simultaneously improved in practical selective breeding programs. This first ever report of genetic parameters for cooked or uncooked colour in crustacean indicates there is potential for genetic improvement of both growth and body colour through selection. Conclusions: In the present study we demonstrated for banana shrimp that genetic parameters can be estimated from commercial samples (using pedigrees based on DNA markers), that selection for shrimp colour should be successful under such commercial conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Wild caught jelly prawns from Moreton Bay, Australia, displayed visible opacity of the hepatopancreas. • Affected jelly prawns were infected by a novel haplosporidian parasite infecting all cell types within the hepatopancreas. • This is the first record of haplosporidiosis in sergestid shrimp, and the new haplosporidian is described as Haplosporidium acetes n. sp. • A novel microsporidian parasite infected hepatopancreatic epithelial cells of one jelly prawn. Wild Acetes sibogae australis from northern Moreton Bay, Australia displaying opacity of the hepatopancreas were sampled and examined histologically, revealing infection by multinucleate plasmodia of a haplosporidian-like parasite in the epithelial cells of the hepatopancreas. A morphological and phylogenetic investigation identified the parasite as a novel species of the order Haplosporida, and the parasite is described as Haplosporidium acetes n. sp. This is the first report of disease caused by a haplosporidian in wild Australian decapod crustaceans, and the first record of haplosporidiosis in sergestid shrimp. Infections of H. acetes were observed in all cell types (R, B, F and E) within the hepatopancreas. Infected epithelial cells became hypertrophied as they filled with haplosporidian parasites and, in heavy infections, caused almost complete displacement of normal hepatopancreas tissue. Although sporulation was not observed, infected jelly prawns appeared terminally diseased. Infections became grossly evident in around 5% of wild prawns during early autumn at a time of year when jelly prawn populations decline rapidly with decreasing water temperatures, however histopathology indicated at least 13% of apparently normal jelly prawns were also infected. Further studies are required in order to determine if this parasite influences jelly prawn population dynamics. In addition, we report co-infection of a novel microsporidian parasite in the Enterocytozoon Group Microsporidia (EGM) infecting nuclei of hepatopancreatic epithelial cells. The microsporidian was phylogenetically distinct from Enterocytozoon hepatopenaei (EHP) known to infect penaeid shrimp in Asia. [ABSTRACT FROM AUTHOR]

Improving the seedstock production of domesticated broodstock remains a high priority for the black tiger shrimp, Penaeus monodon, farming industry in Australia and other shrimp farming regions. In this study, wild-caught (W) broodstock were reciprocally crossed with eighth generation (domesticated-selected) broodstock (G8) and the reproductive performance was evaluated to identify the key parameters and gender influences currently constraining seedstock production from domesticated broodstock. Nauplii production was significantly lower in G8 than W broodstock and differences in nauplii production were found to be more influenced by the female than the male origin of the broodstock. The main constraints on nauplii production in G8 females were inferior egg hatch rates and egg production. The percentage of eggs that hatched was 44% lower in G8 females (24.3%) than W females (43.7%). The total number of eggs per spawning was 25% lower in G8 females (413,000) than W females (552,000) and the relative number of eggs spawned per gram female body weight was 37% lower in G8 females (2476) than W females (3909). In addition, a significantly higher percentage of the W females (70.8±5.7%) matured to ovary stage 4 than G8 females (2.1±2.1%). But there was no difference in the percentage of females that developed stage 3 ovaries or the percentage of females that spawned. There was no difference in the total number of sperm per spermatophore or sperm quality (based on acrosome reaction) between W and G8 males, which may explain the lack of any male effect on fertilization. Our results suggest that female broodstock quality may often explain the low nauplii output of domesticated broodstock. [ABSTRACT FROM AUTHOR]

The Northern Prawn Fishery (NPF) is one of Australia's most valuable federally managed fisheries. It has also been a focus for modelling in Australia, with over 40 years of development of bioeconomic, stock assessment and management strategy evaluation models that have been used to varying degrees to inform management. The current management model has been in operation for over 10 years and is used to set the total allowable effort (TAE) for the tiger prawn (Penaeus semisulcatus and P. esculentus) component of the fishery, historically undertaken after a mid-year closure. The success of management has resulted in increased stocks of tiger prawns, and a fishery before the mid-year closure during which fishing for banana prawns was historically the main activity. While the current management model includes the consequences of fishing for tiger prawns during the first season in terms of which weeks are available for fishing for tiger prawns when estimating the TAE, the lack of explicit inclusion of banana prawns in the bioeconomic modelling has resulted in concerns that the TAE may be biased, as effort is allocated in the model to tiger prawns that, in reality, should be applied to banana prawns. The current model was consequently extended to include an explicit banana prawn component, and a range of scenarios undertaken to explore the impact of this on the management advice. It was found that the current model overestimates the optimal level of effort to be applied to tiger prawns except during periods of very low banana prawn abundance. Banana prawns, which vary substantially inter-annually due largely to environmental drivers, were also found to be the key driver of the level of overall fishery profit, suggesting that greater attention to this component of the fishery may be necessary to achieve the objective of maximizing net economic returns from the NPF. [ABSTRACT FROM AUTHOR]

Disease presents a considerable challenge to the sustainability and development of global shrimp aquaculture. The Australian black tiger shrimp (Penaeus monodon) aquaculture industry is heavily reliant on wild-sourced broodstock for seedstock production, representing a large and under evaluated biosecurity risk. Currently, there is a paucity of quantitative, large-scale data detailing the extent of pathogenic agents in wild-sourced P. monodon broodstock. This study presents a comprehensive investigation of the presence and level of detection of endemic pathogen targets in wild-sourced P. monodon broodstock collected from the two primary sources of supply for the Australian shrimp aquaculture industry using quantitative polymerase chain reaction (qPCR). Broodstock pleopod samples (N = 7472) were analysed by TaqMan qPCR for the detection of six viral pathogens. In total, 44.9% of wild-sourced broodstock were positive for the detection of at least one pathogen target. White spot syndrome virus and yellow head virus-1 were not detected in any sample. Infectious hypodermal haematopoietic necrosis virus (30%) and gill-associated virus (28.1%) were the most prevalent pathogen targets detected. Whenzhou (syn. Wenzhou) shrimp virus-2 and yellow head virus-7 were each cumulatively detected in less than 3% of broodstock samples. Geographic source, sex and year of collection of broodstock significantly influenced prevalence of detection. The current study will be valuable to the Australian shrimp aquaculture industry to improve understanding of the presence of pathogens in wild-sourced broodstock, along with informing management decisions related to wild broodstock collection and associated biosecurity practices. • 7472 wild-sourced P. monodon from two northern regions in Australia were sampled. • WSSV, YHV-1, YHV-7, IHHNV, GAV and When-2 were screened for using Taqman qPCR. • WSSV and YHV-1 were not detected, however, endemic pathogens were highly prevalent. • Broodstock geographic source and sex significantly influenced pathogen detection. [ABSTRACT FROM AUTHOR]

[Display omitted] • First report of monodon baculovirus (MBV) from mud crab, Scylla serrata. • Provided the histological and molecular evidences of MBV in hepatopancreas of crab. • Provided the histological evidence of hepatopancreatic parvovirus (HPV)-like inclusions in S. serrata. During a survey of farmed and wild crustaceans from India for viruses, spherical baculovirosis otherwise known as Penaeus monodon -type baculovirus (MBV) was detected in field-collected juvenile/sub-adult mud crab, Scylla serrata using a nested polymerase chain reaction (PCR)-based amplification of the hepatopancreatic DNA. Eight out of 115 mud crab (7.0%) examined during the study were found to be positive in the nested PCR resulting in a 361 nt amplicon. Mud crab, S. olivacea and other crustaceans such as marine crab, Portunus sanguinolentus and farmed penaeid shrimp, Penaeus vannamei and P. monodon were tested negative for the virus. Further, degenerate primers reported to amplify polyhedrin protein gene of MBV also showed PCR amplification in one of the MBV-positive crab samples resulting in a 250 nt amplicon. Sequencing of the two target amplicons (MBV- 361 nt and MBV polyhedrin – 216 nt) revealed more than 97.5 % and 92.8% sequence identity, respectively with the Penaeus monodon nudivirus and Penaeus monodon nucleopolyhedrovirus (MBV) reported from shrimp. Further, histological analysis of mud crab revealed nuclear hypertrophy, chromatin margination and intranuclear eosinophilic/basophilic inclusions in tubule epithelium of hepatopancreas. The hepatopancreatic tissue also showed unusually large, eosinophilic/basophilic inclusion-like structures. These inclusions resembled the viral inclusions reported from S. serrata from Australia. This is the first record of monodon-type baculovirus from a crab host and the second from a non-penaeid crustacean. Interestingly, some of the crab samples also showed deeply basophilic intranuclear inclusion-like bodies resembling hepatopancreatic parvovirus group of viruses (HPV). However, none of the crab samples subjected to PCR amplification using HPV-specific primers showed any amplification. The histological observations made in the present study indicate the possibility of the presence of two hepatopancreas-infecting viruses in S. serrata from India. [ABSTRACT FROM AUTHOR]

Stochastic growth models were fitted to length-increment data of eastern king prawns, Melicertus plebejus (Hess, 1865), tagged across eastern Australia. The estimated growth parameters and growth transition matrix are for each sex representative of the species' geographical distribution. Our study explicitly displays the stochastic nature of prawn growth. Capturing length-increment growth heterogeneity for short-lived exploited species such as prawns that cannot be readily aged is essential for length-based modelling and improved management. [ABSTRACT FROM AUTHOR]

Abstract: Offshore catches of banana prawns, Penaeus merguiensis, are correlated with the extent of mangrove forests. However, recent evaluation has questioned whether the apparent relationship between juvenile penaeids and mangroves reflects specific utilisation of mangroves or just the use of shallow, organically rich, muddy habitats. We investigated this by focussing on juvenile P. merguiensis within 30 mangrove estuaries spanning 650 km of the coast of north-eastern Australia. We investigated a range of hierarchically clustered spatial scales and within-estuary spatial resolutions, as well as variables representing a variety of estuary structural factors, anthropogenic impacts, and particular hypotheses about the ways in which mangroves could influence P. merguiensis catch per unit effort (CPUE). Estuary to estuary differences, rather than climatic zone or the proximity of other estuaries, was the major large scale spatial influence on CPUE. At the among-estuaries scale mangrove extent appeared to influence CPUE but was extensively confounded with the effects of two non-mangrove variables; intertidal extent and substrate type. The fact that 3 alternative measures of connectivity with mangrove forests were not influential, points to the importance of the non-mangrove variables rather than mangrove extent. At the within-estuary scale, P. merguiensis CPUE was correlated with the extent of shallow water but not with mangrove variables. The spatial and temporal extent of sampling support a strong conclusion that factors associated with mangroves alone do not drive abundances of juvenile prawns. Nevertheless, despite being the dominant habitat, mangroves are only one of a mosaic of interacting habitats occurring in the tropical estuaries inhabited by juvenile penaeids (Sheaves, 2009), so causal relationships are complex and difficult to define unambiguously. [Copyright &y& Elsevier]

Pharmaceutical companies and manufacturers of food products are legally required to label the product's shelf-life on the packaging. For pharmaceutical products the requirements for how to determine the shelf-life are highly regulated. However, the regulatory documents do not specifically define the shelf-life. Instead, the definition is implied through the estimation procedure. In this paper, the focus is on the situation where multiple batches are used to determine a label shelf-life that is applicable to all future batches. Consequently, the short-comings of existing estimation approaches are discussed. These are then addressed by proposing a new definition of shelf-life and label shelf-life, where greater emphasis is placed on within and between batch variability. Furthermore, an estimation approach is developed and the properties of this approach are illustrated using a simulation study. Finally, the approach is applied to real data. [ABSTRACT FROM AUTHOR]

Further information on the little known pontoniine shrimps, Periclimenaeus quadridentatus Rathbun, 1906 and P. crassipes (Calman, 1939), is provided and illustrated, and Periclimenaeus calmani sp. nov, from the Cobourg Peninsula, Northern Territory, Australia, and P. serenei sp. nov., from Nha Trang, Vietnam, are designated. [ABSTRACT FROM AUTHOR]

Abstract: The use of visual and chemical cues in host detection is regarded as important but relatively unknown for many symbionts. The small circumtropical caridean shrimp Gnathophylloides mineri forms a close symbiotic association with sea urchins, particularly Tripneustes gratilla, in many parts of the world. G. mineri is known to occur in temperate eastern Australia but the breadth of host use and selection of hosts amongst different species of sea urchins is relatively unknown. The abundance of G. mineri on three co-occurring species of sea urchins, T. gratilla, Heliocidaris tuberculata and Pseudoboletia indiana were measured in eastern Australia. These species of sea urchins were chosen because of either a known prior association with this shrimp elsewhere in the world, or due to their abundance in the area in temperate Australia where the shrimp occurs. Field collections showed that the association between shrimp and sea urchin appears extremely host-specific, with G. mineri only observed on T. gratilla, at an average density of two shrimp per sea urchin. Moreover, the majority of symbionts occurred on the underside (oral region) of T. gratilla. A visual laboratory experiment showed that G. mineri would actively move towards T. gratilla in preference to the other potential host species in the absence of chemical signals. Using a Y-maze, we tested the reaction of G. mineri to the absence of visual signals but the presence of chemical signals originating from their host, and from other species of potential host sea urchins. Seawater alone was used as a negative control. We demonstrated that G. mineri could detect T. gratilla from a distance, the same host that the shrimp are associated with in the field, using visual and chemical cues. Moreover, G. mineri react quickly to visual and chemical host signals by moving towards T. gratilla in preference to other species of sea urchins or in the absence of a signal. The relative importance of visual versus chemical cues is, however, unknown. [Copyright &y& Elsevier]

Abstract: Since bycatch reduction devices (BRDs) were first tested in Australian penaeid-trawl fisheries almost 20 years ago, there have been ongoing refinements to a discrete range of legislated designs; mostly in response to dynamic fishery-specific operational requirements. This study assesses the relative utility of the latest versions of two generic BRDs that have evolved/devolved in an estuarine fishery. Compared with a codend containing no BRD, a simplified Nordmøre-grid and radial escape section significantly reduced the total weight of bycatch by 74 and 36%, respectively. Catches of the targeted school prawns (Metapenaeus macleayi) were also reduced by 4 and 11%, respectively, although, at least for the Nordmøre-grid, these losses were apparently offset by the practicality of the revised design in terms of a simpler and cheaper construction. The presence of large quantities of displaced submerged plants (e.g. Egeria densa and Hydrilla verticillata) on the trawl grounds at certain times (which preclude using the Nordmøre-grid) may similarly compensate for the reduced efficiency of the radial escape section. In addition to quantifying the performance of the revised BRDs, the results provide direction for their future refinement in this and other similar fisheries. [Copyright &y& Elsevier]

Gill-associated virus (GAV) was found to be associated with decreased prawn, Penaeus monodon, production when prawns from three farms ( n = 45 ponds, 1800 prawns) were monitored for GAV over the production season using a graded RT-nPCR. The grading system used was a visualization of either the outer or inner nested PCR products. Prevalence and loading of GAV were associated with disease severity. Ponds with a higher initial prevalence and a larger increase in GAV load over the production period suffered disease outbreaks. Ponds with low initial prevalence of GAV but a larger increase in prevalence and large increase in load over the production period suffered chronic disease with no disease outbreak identified, yet low production. However, the ponds with moderate to low initial prevalence of GAV with a low increase in prevalence and load of GAV over the production period incurred no disease outbreak and comparatively high production. Ponds with GAV prevalence greater than 75% at 1 month post-stocking should be considered for termination as they have a high probability (95%) of having a disease outbreak. Emergency harvest when a disease outbreak occurs will significantly limit mortality losses. [ABSTRACT FROM AUTHOR]

The species diversity of pontoniine shrimps (Decapoda: Palaemonidae: Pontoniinae) previously recorded in the vicinity of Lizard Island, Great Barrier Reef (GBR), Australia, were compared with new records obtained during a recent three-week expedition as part of the CReefs Project, a field project of the Census of Marine Life. Few previous investigations at this location had discovered 18 species of pontoniine shrimps distributed among 12 genera. In contrast, relatively little effort, approximately 35 hours sampling (40 dives), was required to increase this list more than twice adding 20 new species records from 15 pontoniine genera for the locality including 6 species and 1 genus reported from Australian waters for the first time and 1 genus and 4 species new to science. This large increase in species was enumerated with little additional effort and the relatively low total species diversity of these shrimps known from this location compared to species known from the southern GBR (e.g. Heron Island), where overall diversity is expected to be less, strongly indicates that the enumeration of these shrimps from the northern GBR is far from complete. [ABSTRACT FROM AUTHOR]

Abstract: The culture of mud crabs Scylla serrata (Forskal) is largely experimental in Australia but some operators are producing marketable quantities. In an effort to understand the bottlenecks to production in hatcheries, a number of disease studies were initiated. In one study, basophilic to particularly magenta, intranuclear inclusions consistent with intranuclear bacilliform virus were discovered in the hepatopancreas of ~9% of wild broodstock and ~13% of batches of their progeny larvae. The inclusions were highly focused in hepatopancreatic tubules with 13-42% of tubules infected. Concurrently, using quantitative real-time Taqman PCR, ~74% of haemolymph samples of adults and 50% of batches of larvae were positive for Penaeus merguiensis Densovirus (PmergDNV) with copy numbers ranging from 6×102 to 1.5×105. Sequencing of 2475 base pairs of viral genome confirmed that the virus was 99% similar to PmergDNV. This is the first record of one of the members of the hepatopancreatic parvovirus group of viruses to be found outside penaeid prawns. This study demonstrates that there are at least two viruses circulating in mud crab populations in northern Australia that might impact on hatchery production. [ABSTRACT FROM AUTHOR]

1. The response of a species to environmental disturbance is largely mediated by its life history traits that have evolved within a particular habitat template. Altered flow seasonality, as a direct consequence of river regulation, is a major environmental disturbance and has been implicated in the redistribution of a range of riverine organisms. An understanding of the reasons for species-specific responses, however, has proved elusive. 2. Here, we investigated the reproduction of three riverine shrimp species ( Paratya australiensis, Caridina mccullochi and Macrobrachium australiense) that show contrasting patterns in distribution and abundance in regulated Australian rivers. 3. In all three species, breeding females were largest, and fecundity was greatest early in the breeding season (November–December). Fecundity and egg size subsequently declined, with lower investment (overall and per offspring) perhaps indicating that conditions for larvae were more favourable later in the breeding season (a time normally characterised by low flow, warm water and high productivity). 4. Interspecific differences in absolute values of reproductive traits were, however, striking. Paratya australiensis has typically ‘opportunistic’ traits (small body size, small eggs and high fecundity), whereas M. australiense has more ‘equilibrium’ traits (larger body size, larger eggs and moderate fecundity). Caridina mccullochi is intermediate, having neither high fecundity nor large size, and has limited swimming ability when young. This species is now absent from at least one heavily regulated river in south-eastern Australia, and we hypothesise that its life history may explain this absence. 5. Studies involving aspects of life history, such as reproductive traits, are likely to improve our understanding of a range of organisms and assist in the management of disturbed or altered environments. [ABSTRACT FROM AUTHOR]

This study investigated the importance of dispersal and retention processes during early ontogeny for three caridean shrimp species that complete their entire life history in freshwater. Directional traps were used to examine the small-scale movement patterns of shrimp into and out of nursery habitat patches (slackwaters) in a small lowland river in southeastern Australia. Movement patterns provided evidence for two contrasting life history based dispersal and retention strategies. For the two smaller atyid species, Paratya australiensis and Caridina mccullochi, the majority of larvae remained within the slackwater in which they were hatched until the final stage of development, at which point dispersal, either among slackwaters or out of slackwaters to faster-flowing pool and run habitats, occurred. For the larger palaemonid species, Macrobrachium australiense, larvae were hatched into slackwaters and dispersal occurred predominately during the first stage of larval development and then decreased as development progressed. Despite the differences in dispersal strategies among species, movement was mostly associated with a particular larval stage and thus emphasizes the importance of retention during critical developmental periods and of the potential impact that flow alteration could have on these and other species with similar life histories. Notre étude examine l’importance des processus de dispersion et de rétention durant le début de l’ontogenèse chez trois espèces de crevettes caridéennes qui complètent tout leur cycle biologique en eau douce. Des pièges directionnels ont servi à déterminer les patrons de déplacement des crevettes à petite échelle à l’entrée et la sortie des taches d’habitat de nourricerie (étales de courant) dans une petite rivière de plaine dans le sud-est de l’Australie. Les patrons de déplacement démontrent l’existence de deux stratégies bien disctinctes de dispersion et de rétention basées sur les cycles biologiques. Chez les deux espèces plus petites d’atyidés, Paratya australiensis et Caridina mccullouchi, la majorité des larves demeure dans l’étale où elles ont éclos jusqu’aux derniers stades de leur développement; à ce moment a lieu la dispersion, soit entre les étales, soit des étales vers les habitats d’eau plus rapide des profonds et des rapides. Chez l’espèce de palaemonidé de plus grande taille, Macrobrachium australiense, les larves éclosent dans les étales et la dispersion se fait surtout durant le premier stade du développement larvaire pour ensuite diminuer au cours du développement. Malgré les différences de stratégie de dispersion entre les espèces, les déplacements sont surtout associés à des stades larvaires particuliers. Cela souligne l’importance de la rétention durant les périodes critiques du développement et l’impact potentiel des modifications de débit sur ces espèces et sur d’autres espèces à cycle biologique semblable. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the habitat preference as an attempt to drive the distribution of postlarval prawn called Penaeus plebejus in Australia. It compares the occupancy of complex and simple habitat as well as its predation mortality. The result of the study shows that mortality of postlarvae prawns caused by the predatory fishes such as Centropogan australis and Acanthopagrus australis was higher in simple habitats. It also reveals that predation risk of postlarvae can be minimized by releasing the stocked larvae in the macrophyte habitats during the day and night.

Records of extinct organisms interacting with each other are limited primarily to evidence of predation and records of parasitism. However, in rare cases, records of organisms living within another one (inquilinism) have been identified. To expand the rather limited record of documented euarthropod inquilinism, we present a new example of three articulated swimming shrimps within an inoceramid bivalve from the Cretaceous (Albian) Allaru Mudstone, Queensland, Australia. We suggest that the specimen represents the first record of decapod inquilinism from Australia and the first record of extinct shrimps within a bivalve. We also show an inoceramid from the same area and age containing at least 30 fish, a specimen that supports the inquilinism hypothesis. Further examination of these rare specimens is a cardinal direction to better understand how extinct crustaceans interacted with other organisms and to document where and when inquilinism evolved across the Phanerozoic. • Reviewed the evidence of decapod-mollusc inquilinism. • Document the oldest record of decapod-bivalve inquilinism in the fossil record and Australia. • Explore possible implications for inquilinism in arthropods across the Phanerozoic. [ABSTRACT FROM AUTHOR]

Abstract: A suite of management options for a prawn trawl fishery in Torres Strait, Australia was assessed for impacts on the benthic fauna using a dynamic management strategy evaluation approach. The specification of the management options was gained through consultation with stakeholders. Data for the model was drawn from several sources: the fleet data from fishery logbooks and satellite vessel monitoring systems, benthic depletion rates from trawl-down experiments, benthic recovery rates from post-experiment recovery monitoring studies, and benthic distribution from large-scale benthic surveys. Although there were large uncertainties in the resulting indicators, robust measures relevant to management were obtained by taking ratios relative to the status quo. The management control with the biggest effect was total effort; reducing trawl effort always led to increases in benthic faunal density of up to 10%. Spatial closures had a smaller benefit of up to 2%. The effect of closing a set of buffer zones around reefs to trawling was indistinguishable from the status quo option. Closing a larger area, however, was largely beneficial especially for sea cucumbers. When the spatial distributions of fauna prior to fishing were accounted for, fauna with distributions positively correlated with effort improved relative to those negatively correlated. The reduction in prawn catch under effort reduction scenarios could be ameliorated by introducing temporal closures over the full-moon period. [Copyright &y& Elsevier]

The thalassinidean ghost shrimps Trypaea australiensis and Biffarius arenosus are dominant burrowing macroinvertebrates of soft-sediment habitats in Western Port, Victoria, Australia. Burrow structure has been described for both species but little is known about how the burrows change over time. This study used resin casting to investigate temporal variation by making burrow casts each month over a 12-month period. It was found that the overall burrow morphology of both T. australiensis and B. arenosus was consistent over time, but in the warmer months (summer and spring), both species constructed burrows that were deeper and of greater volume than burrows constructed in winter and autumn. Possible reasons for this variation are discussed. [ABSTRACT FROM AUTHOR]

Large areas of uncompacted cyanobacterial accumulations (or “gyttja”) have been observed in Myall Lake, New South Wales, Australia. To determine whether the cyanobacterial accumulations were assimilated into the local food web, carbon and nitrogen stable isotopes were used to identify the primary food sources of a primary consumer in Myall Lake, the freshwater atyid shrimp Paratya australiensis. Suspended particulate organic matter (POM) and the macrophyte Myriophyllum salsugineum were identified as major dietary sources of P. australiensis. Enriched stable isotope signatures (δ13C and δ15N) of shrimp from gyttja-affected sites, relative to shrimp from unaffected locations, also indicated that P. australiensis were deriving a considerable portion of their dietary carbon and nitrogen requirements from gyttja. Stable isotope mixing models estimated that cyanobacterial accumulations might constitute up to 69% of P. australiensis biomass carbon and nitrogen requirements at gyttja-affected locations. To our knowledge, this is the first study to use stable isotope analysis to trace the assimilation of potentially toxic cyanobacterial accumulations into the trophic pathways of an affected system. [ABSTRACT FROM AUTHOR]