https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:39161 in situ microhabitat assessments to assess whether reef fish community structure on shallow (6-9 m) rocky reefs varied with spatial management zone (NTAs versus PPAs), sampling season (autumn, spring) and benthic habitat condition around coastal islands and headlands within the Port Stephens-Great Lakes Marine Park (established in 2007). While fish community composition and the relative abundance of fish species did not differ significantly across spatial management zones, there were significant differences among sampling season, and spatial variation at the site level that was partly explained by geomorphology (island/headland). Notably, there was a strong association between variation in fish community structure and site-level cover of canopy-forming macroalgae among islands and headlands, which transcended management zones. Our study suggests that balancing habitat condition and geomorpho-logical setting (islands, headlands) among management zones is key to the conservation and management of shallow-water reef fish assemblages. In particular, the percent cover of canopy-forming macroalgae may be a key habitat indicator for designing, monitoring and re-balancing spatial management zones.]]> Wed 22 Mar 2023 18:16:59 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:55228 470 km of SE NSW coastline. Diverse items were present in the digestive tracts of urchins from all habitats. These items included brown (42% barrens, 46% macroalgae), green (28% barrens, 42% macroalgae) and red algae (15% barrens, 12% macroalgae) and corallines (29% barrens, 37% macroalgae), molluscs (28% barrens, 29% macroalgae) and crustaceans (26% barrens, 22% macroalgae). There was no difference in urchin gut fullness between habitats (85% barrens, 90% macroalgae). Importantly, the gonad index only differed in macroalgae compared to barrens habitats at one location, with no differences detected at the other 4 locations. These results suggest that C. rodgersii has a diverse diet that is similar in both habitats, which could explain the similarities in gut fullness and gonad index. Our results suggest that C. rodgersii eat a broad diet including invertebrates and drift algae, and hence may not be malnourished in barrens. The finding of comparable gonad index between barrens and macroalgal areas further supports this conclusion. These findings challenge the prevailing perspective, indicating that sea urchins have sufficient food to survive and reproduce in different habitats.]]> Wed 01 May 2024 15:33:18 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:1456 Sat 24 Mar 2018 08:28:09 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:17280 Sat 24 Mar 2018 08:01:49 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:37668 Dendronephthya australis, with its limited distribution along the central New South Wales (NSW) coastline, forms a habitat within the benthic estuarine environment that supports commercially significant and protected marine species. However, the functional role of the soft coral within this system is unknown. Organisms from primary producers through to secondary consumers were sampled from soft coral and sponge habitats inside the Port Stephens estuary, NSW, Australia in 2014. A food web model of the benthic habitat, created using stable isotopes of carbon and nitrogen, was used to describe the functional role of the soft coral in comparison to sponges, another important habitat for commercially significant and protected marine species. Primary consumers accessed a range of benthic and pelagic energy sources; however, secondary consumers were almost entirely dependent on pelagic energy sources. Soft coral and sponges accessed different primary sources for their energy requirements. There was no evidence that D. australis was used as a direct food source by consumers other than nudibranchs. In contrast, sponges were trophically linked with secondary consumers and are likely to play a direct role in pelagic energy transfer. Amphipods collected from the branches of D. australis were identified as major prey components in the diet of protected syngnathids, suggesting that while the soft coral functions as critical habitat, it is indirectly linked to higher trophic levels.]]> Fri 25 Jun 2021 13:34:15 AEST ]]>