https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39544 60 % of the biomass was required to obtain an accurate estimate of abundance for rarer species. The careful consideration of program objectives is important in optimising the sampling approach employed, as subsampling may not be appropriate for detection of rare species. The patterns presented here provide a quantitative basis to support sampling and sorting methodology for multispecies trawl samples, as well quantifying the implications of subsampling on the confidence in estimates of diversity or abundance.]]> Wed 27 Jul 2022 14:25:17 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:52172 Wed 04 Oct 2023 10:55:46 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:41927 Metapenaeus macleayi), through a series of experiments conducted under normal (pH 8) and acidic (pH 5) conditions. Experimental data were used to examine mortality. Also, histological examination of the gills and hepatopancreas was conducted to determine pathological consequences of exposure to these stressors. School Prawn did not experience mortality in response to acute exposure to Al under normal pH conditions, but mortality and tissue bioaccumulation of Al was greater under acidic conditions, suggesting an interactive effect of both stressors. Histology revealed sub-lethal effects of Al including structural abnormalities in the gills and hepatopancreas, and evidence of viral infection and immune response, particularly at lower pH and higher Al concentrations. These impacts may impede major vital functions such as respiration, osmotic regulation, metabolism and growth of juvenile School Prawn, which could contribute to productivity bottlenecks in degraded estuaries.]]> Tue 16 Aug 2022 11:19:40 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43117 Tue 13 Sep 2022 14:25:26 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:51216 Thu 24 Aug 2023 15:06:05 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:31277 Penaeus [Melicertus] plebejus) and School Prawn (Metapenaeus macleayi) were studied for two years in the lower Hunter River estuary, on the temperate east coast of Australia. The higher salinity areas near the lower end of the estuary were most important for Eastern King Prawn, and marsh systems in the lower estuary were only important for the species where there was good connectivity with oceanic water. Areas along the estuary were important for juvenile School Prawn, especially marsh habitats, and relative abundance tended to increase with increasing distance along the estuary. Designation of effective juvenile habitat for School Prawn may have been affected by high fishing mortality in fished areas, but this requires further investigation. Salinity, depth, turbidity and distance along the estuary were all important indicators of prawn distribution. The implications of these patterns for current and future habitat rehabilitation in temperate Australia are discussed.]]> Sat 24 Mar 2018 08:44:32 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:31392 Penaeus [Melicertus] plebejus), and the processes that contributed to this nursery role. Stable isotopes were used to assign prawns joining the adult stock to putative nursery habitat areas within the estuary. Emigrating prawns originated from only 11 of the 20 sites surveyed. Of these, 8 sites were designated as Effective Juvenile Habitat (EJH), and 5 sites designated as Nursery Habitat (NH). The contribution of individuals from different nursery areas to the adult stock was related to both the abundance of prawns within an area and the distance to the mouth of the estuary, and with the exception of 1 site all EJH and NH were located in the northern section of the estuary. Quantitative sampling in this area indicated that prawns were present at an average density of 165 ± 11 per 100 m², and density formed non-linear relationships with the distance to the mouth of the estuary, seagrass cover and temperature. Prawn size also formed non-linear relationships with prawn density and seagrass cover. Spatial patterns in abundance were consistent with wind-driven recruitment patterns, which in turn affected the nursery role of particular areas within the system. These findings have implications for targeted fishery restoration efforts for both Eastern King Prawn and other ocean spawned species in wave dominated estuaries where circulation is primarily wind-driven.]]> Sat 24 Mar 2018 08:43:01 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:30702 Metapenaeus macleayi) and Mud Crab (Scylla serrata), two commercially important crustaceans in Australia. Perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), and perfluorooctanoic acid (PFOA) were present in samples of both species collected following exposure under natural conditions in contaminated estuaries. Depuration was tested in uncontaminated water for 33 days. PFOA was present at levels close to LOR in both species, and was not detected after 4.5 h and 72 h in School Prawn and Mud Crab respectively. PFHxS was rapidly depurated by School Prawn, and had a depuration half-life of 5.7 h. PFOS was also depurated by School Prawn, with a depuration half-life of 158.5 h. PFHxS and PFOS concentrations were highly variable in Mud Crab both at the start, and during the depuration experiment, and a depuration model could not be fitted to the data. For School Prawn, depuration of total PFASs to the relevant screening value for protection of human health (9.1 μg kg^{− 1}) occurred within 7.1 h. Rapid depuration of PFASs in School Prawn indicates that human health risks associated with consumption may decrease as this species migrates away from the contamination source. Further research is required to better understand the relationships between contaminant load and life-history characteristics (such as growth, reproduction, and moult cycle) in Mud Crab, and future work should target broader time frames for depuration in this species.]]> Sat 24 Mar 2018 07:35:08 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:42620 Mon 29 Aug 2022 08:32:13 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48516 Mon 20 Mar 2023 17:00:06 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:37144 Fri 21 Aug 2020 12:35:43 AEST ]]>