https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:52895 Tue 31 Oct 2023 15:46:14 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:44300 Tue 11 Oct 2022 16:05:32 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36708 Pagrus auratus) where more than 10% of the total catch is comprised of unwanted elasmobranchs and the presence of elasmobranchs reduces the catch of target species. Over 1000 fish traps were deployed in a fishery-dependent survey in New South Wales, Australia. Standardised catch rates indicate that the incorporation of magnets into fish traps significantly reduced incidences of elasmobranch bycatch (mainly Brachaelurus waddi) by over a third, while increasing the amount of target fish caught by an equivalent amount. Together these results suggest that magnets can be used as an effective bycatch reduction device that reduces incidences of elasmobranch bycatch while increasing the profitability of fish traps for fishermen. Future studies should aim to replicate these results in areas where different species of elasmobranchs occur.]]> Thu 25 Jun 2020 15:56:41 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36707 Catostylus mosaicus, can be rapidly estimated over much larger areas than traditional field sampling and without requiring fishing effort. Estimated biomass within Smiths Lake, New South Wales, Australia was roughly 350 kg per hectare, and size frequency distributions were skewed towards larger specimens compared to previous studies in other locations. Drone counts were similar to a visual census which provides further evidence that this rapid and relatively automated method has potential to be used more widely in ecological monitoring.]]> Thu 25 Jun 2020 15:42:42 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36777 Urolophus cruciatus and U. paucimaculatus, and one draughtboard shark, Cephalocyllium laticeps) in response to an approaching demersal trawl to quantify behavioural factors that affect their catchability. The morphologically similar U.cruciatus and U. paucimaculatus were similarly abundant, i.e. 290 and 218 individuals, respectively, but displayed different net avoidance behaviours, with U. paucimaculatus being far more likely to enter the trawl. The greater catchability of U. paucimaculatus would falsely suggest this less common species was more abundant than U. cruciatus, which has implications for any assessments of the impacts of trawling on these two elasmobranchs. Collision with trawl gear was relatively common for both Urolophus spp., and this was shown to decrease their likelihood of capture. In contrast, only 1 of the 68 individuals of the morphologically-different C. laticeps collided with gear. These results will help inform future development of BRDs and highlight that understanding the behaviour of elasmobranchs in response to capture methods should form an integral component of assessments of the impacts of trawling on this highly affected group.]]> Thu 16 Feb 2023 10:01:07 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:54262 Thu 15 Feb 2024 12:25:04 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:52213 Thu 05 Oct 2023 10:23:35 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:51386 Mon 04 Sep 2023 13:11:51 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:40550 Pristiophorus nudipinnis), to guide future research in this area. To identify where the animals may occur in greater numbers, this study used the major commercial fishery datasets in the region, containing nearly 180 000 catch records from 1990 to 2017. Several general patterns were evident. Sawsharks occurred at shallower and deeper depths than previously thought, and their geographical range was larger than documented in previous studies. Depth distributions of both species overlapped, but P. cirratus appeared more common in deeper water (at depths up to 500 m), with peak common sawshark catch rates at ~400 m. Seasonal standardised catch patterns across fishing methods suggested that migrations from deeper to shallower waters may occur in the Australasian autumn and winter. The greatest concentration of sawsharks, inferred by standardised catch rates, occurred to the east and west of Bass Strait between Tasmania and mainland Australia. Although standardised catch rates of sawsharks declined in gill-net fisheries by ~30%, primarily in the Bass Strait and Tasmania, sawsharks appear to be caught at consistent rates since the 1990s, inferring a possible resilience of these sharks to current levels of fishing pressure.]]> Fri 22 Jul 2022 15:24:27 AEST ]]>