https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48212 Wed 28 Jun 2023 20:19:32 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40517 Wed 19 Apr 2023 10:00:48 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:52457 Wed 11 Oct 2023 15:03:14 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:31429 Chelidonichthys kumu, Grooved Gurnard Lepidotrigla modesta, and Roundsnout Gurnard Lepidotrigla mulhalli), were examined for the presence of such dietary niches. The species are either fishery-important (Red Gurnard) or provide prey (Grooved Gurnard and Roundsnout Gurnard) for fishery-important species (e.g., Platycephalidae and Zeidae). Based on stomach content analyses, all three gurnards were shown to be bottom-feeding carnivores that consumed mainly benthic crustaceans, particularly decapods and amphipods, with teleosts also being important in the diets of only the larger Red Gurnard. Nonmetric multidimensional scaling ordination and multivariate analyses based on volumetric contributions of different prey taxa to the stomach contents revealed significant differences in dietary composition among all three species, implying a partitioning of food resources. Size-related and temporal changes in dietary composition were each significant among the three gurnards, but there were no interactions between body size and time. Principal components analysis of head and mouth morphology demonstrated that mouth protrusiveness was the dominant morphological difference among species, which may in part account for the niche partitioning observed from the stomach content analysis. Given the important role of gurnards in benthic food webs, these relationships will improve the specification of ecosystem-based fisheries models and their ability to predict the effects of environmental and anthropogenic perturbations.]]> Wed 11 Apr 2018 14:09:53 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:31428 3. These results suggest that structure from motion is a viable tool for ongoing monitoring of ecologically-significant coral reefs, especially to establish effects of disturbances, provided the measurement error is considered.]]> Wed 11 Apr 2018 10:45:16 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34869 Cephaloscyllium laticeps) and the piked spurdog (Squalus megalops) in-situ using a remote-operated-vehicle and in a replicated experiment in controlled conditions. In total, 67 sharks were caught with demersal fish trawls and commercial longlines and subjected to different deck exposures and release environments. Tailbeat rates of deck-exposed sharks were significantly lower than the control sharks, but this effect differed between in-situ and experimental environments. Results indicate that capture has species-specific effects, that post-release effects may last longer than 5 min, and that controlled experiments may not be reliable indicators of post-release effects. Immediate post-release swimming was not a good predictor of post-release behaviour, suggesting capture and release fisheries may have significant sub-lethal effects on some species of shark, and that limiting capture or handling time may reduce post-release effects.]]> Wed 09 Jun 2021 13:51:11 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43999 Wed 05 Oct 2022 15:12:27 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33357 Lepidotrigla mulhalli and L. vanessa from south-eastern Australia were analysed using stomach content and stable isotope ratios (δ¹³C and δ¹⁵ N). Both species are bottom-feeding carnivores that consumed mainly benthic crustaceans, but teleosts were also abundant in the diet of larger L. vanessa. Non-metric multidimensional scaling (nMDS) ordination and analysis of similarity (ANOSIM) of dietary data revealed significant inter-specific dietary differences; i.e. food resource partitioning. Carbon (δ¹³C) and nitrogen (δ¹⁵N) stable isotope values were similar between L. mulhalli and L. vanessa, however, suggesting similar trophic positioning. Ontogenetic changes in diet composition and stable isotope values were evident. As L. vanessa grew, they preyed upon larger individuals, such as teleosts and caridean shrmips, but no such trend was observed in the diets of L. mulhalli. Adults of both species were significantly enriched in ¹⁵N relative to juvenile conspecifics thus supporting these data. Consequently, in this study, both methodologies, i.e. stomach content and stable isotope analyses, provided evidence of inter- and/or intra-specific dietary segregations and trophic niche partitioning between co-occurring L. mulhalli and L. vanessa off Tasmanian waters.]]> Wed 04 Sep 2019 09:56:13 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40533 Tue 20 Feb 2024 12:00:49 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40846 Tue 19 Jul 2022 11:15:17 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48304 Tue 14 Mar 2023 14:13:46 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:52386 Tue 10 Oct 2023 14:45:57 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39157 Tue 09 Aug 2022 14:06:40 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:34919 Hemiscyllium ocellatum) displayed sinusoidal movement patterns, while Blacktip Reef Sharks (Carcharhinus melanopterus) had more linear trajectories that were similar to those of a Lemon shark (Negaprion acutidens). Individual shark trajectory patterns and movement speeds were highly variable. Results indicate that Epaulette sharks may be more mobile during diurnal low tides than previously thought. The approach presented here allows the movements and behaviours of marine vertebrates to be analysed at resolutions not previously possible without complex and expensive acoustic arrays. This method would be useful to assess the habitat use and behaviours of sharks and rays in shallow water environments, where they are most likely to interact with humans.]]> Tue 03 Sep 2019 17:58:05 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:38302 Thu 26 Aug 2021 10:22:38 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:37768 Sphyrna mokarran are the largest member of Sphyrnidae, yet the roles of these large sharks in the food webs of coastal ecosystems are still poorly understood. Here we obtained samples of muscle, liver and vertebrae from large S. mokarran (234–383 cm total length; L_T) caught as by‐catch off eastern Australia and used stable‐isotope analyses of δ¹⁵N, δ¹³C and δ³⁴S to infer their resource use and any associated ontogenetic patterns. The results indicated large S. mokarran are apex predators primarily relying on other sharks and rays for their diet, with a preference for benthic resources such as Australian cownose rays Rhinoperon neglecta during the austral summer. Teleosts, cephalopods and crustaceans were not significant components of S. mokarran diets, though some conspecifics appeared to rely on more diverse resources over the austral summer. Ontogenetic shifts in resource use were detected but trajectories of the increases in trophic level varied among individuals. Most S. mokarran had non‐linear trajectories in ontogenetic resource‐use shifts implying size was not the main explanatory factor. Stable isotope values of δ¹³C and δ³⁴S in muscle suggest S. mokarran span coastal, pelagic and benthic food webs in eastern Australia.]]> Thu 15 Apr 2021 10:37:54 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:44452 Thu 13 Oct 2022 15:05:26 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26183 Sat 24 Mar 2018 07:24:11 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48196 Sat 11 Mar 2023 12:30:29 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48176 Sat 11 Mar 2023 12:23:01 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:32832 intermedialis and was generally detected at levels an order of magnitude lower in the corpus calcareum,. In most species, zinc concentrations were higher pre-birth mark, indicating a high rate of pre-natal zinc deposition. These results suggest there are inter-specific differences in elemental deposition within vertebrae. Since the deposition of zinc is physiologically-driven, these differences suggest that the processes of growth and deposition are potentially different in the intermedialis and corpus calcareum, and that caution should be taken when extrapolating information such as annual growth bands from one structure to the other. Together these results suggest that the high inter-specific variation in vertebral zinc deposition and associated physiologies may explain the varying effectiveness of ageing methodologies applied to elasmobranch vertebrae.]]> Mon 23 Sep 2019 12:27:57 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:51902 Fri 22 Sep 2023 09:29:56 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40445 Sphyrna mokarran). Both methods indicated similar geographic ranges and suggested that S. mokarran recorded in south-eastern Australia are likely to be from more northern Australian waters. These approaches could be replicated in other areas where coastlines span predictable geographic gradients in isotope values and be used to determine the core population geography of highly mobile species to inform management decisions.]]> Fri 22 Jul 2022 14:37:03 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40145 Amnoonviridae, a family within the order Articulavirales comprising segmented negative-sense RNA viruses. We sought to identify additional viruses within the Amnoonviridae through total RNA sequencing (meta-transcriptomics) and data mining of published transcriptomes. Accordingly, we sampled marine fish species from both Australia and China and discovered several segments of two new viruses within the Amnoonviridae, tentatively called Flavolineata virus and Piscibus virus, respectively. In addition, by mining vertebrate transcriptome data, we identified nine additional virus transcripts matching to multiple genomic segments of TiLV in both marine and freshwater fish. These new viruses retained sequence conservation with the distantly related Orthomyxoviridae in the RdRp subunit PB1, but formed a distinct and diverse phylogenetic group. These data suggest that the Amnoonviridae have a broad host range within fish and that greater animal sampling will identify additional divergent members of the Articulavirales.]]> Fri 22 Jul 2022 13:49:47 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:41835 Fri 12 Aug 2022 14:23:17 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39513 2 Heron Island Reef in Queensland, Australia. Ex situ bioturbation rates of the most abundant holothurian, Holothuria atra, were assessed during 24-h feeding experiments. Using density measurements of holothurians across reef flat zones in a 27,000 m² map produced from drone imagery, we extrapolated bioturbation across the reef using satellite remote sensing data. Individual H. atra were estimated to produce approximately 14 kg of bioturbated sediment per year. On a reef scale (excluding the reef lagoon) and accounting for varying densities of holothurians across different reef zones, total bioturbation from holothurians at Heron Reef was estimated at over 64,000 metric tonnes per year, slightly more than the mass of five Eiffel Towers. These results highlight the scale of structural and biochemical impacts that holothurians have on reef flats and their importance to ecosystem functioning and services. Management of these animals on reefs is imperative as overharvesting would likely cause substantial negative effects on sedimentary ecosystems and their biogeochemistry in corals reefs.]]> Fri 10 Jun 2022 15:42:34 AEST ]]>