Coral reproduction at Hall Bank, a high latitude coral assemblage in Western Australia

Research on coral reproduction has increased dramatically in recent times; however, there remain significant regions, in particular high latitude reefs, where research is limited. For example, the reproductive biology of species in the coral assemblage at Hall Bank, a high latitude site (32 degrees S) in southern Western Australia, remain unknown. Here, reproductive traits and the likely time of spawning for 12 of the approximately 16 species that occur at Hall Bank were established using histology between March 2009 and March 2011 at 7 discrete time points. Peak reproductive activity most likely occurs in February, as 7 of the 10 species sampled in this month had colonies with mature gametes. The sexuality, mode of larval development and transmission of symbionts were, as expected, consistent with previous work. The reproductive biology of the corals at Hall Bank is consistent with other regions of the Indo-Pacific, supporting the hypo thesis that reproductive traits such as sexuality and mode of larval development are evolutionarily conserved and do not vary biogeographically

Hidden giants: The story of Bolbometopon muricatum at ningaloo reef

Bolbometopon muricatum (bumphead parrotfish, Valenciennes, 1839) is a conspicuous, iconic and ecologically important coral reef fish species. B. muricatum plays an important role in the bioerosion of the reef framework and as a result has been described as both an ecosystem engineer and keystone species. Despite the complete absence of B. muricatum from 32 years of scientific surveys across the Ningaloo Reef World Heritage Area, we recorded a total of 155 individuals of B. muricatum across 63.2 ha of reef crest surveys, equating to mean density of 2.38 ind/ha. Our observations represent the first record of this iconic species in scientific surveys at Ningaloo and in combination with qualitative observations of B. muricatum by expert witnesses, indicate B. muricatum is likely to have been present in ecologically relevant densities since 2006. The densities of B. muricatum observed at northern Ningaloo in 2021 suggest this species is removing an estimated 13.42 tonnes/ha or 1.34 kg/m2 of calcium carbonate per year, which is broadly comparable with estimates of total parrotfish bioerosion across many reefs in the central Indian and Pacific Oceans. Although not currently afforded elevated conservation status within management plans, B. muricatum possess many life-history characteristics that make them vulnerable to overfishing and may justify consideration for increased protection within the world heritage listed Ningaloo Reef Marine Park

Coral larval recruitment in north-western Australia predicted by regional and local conditions

Understanding ecological processes that shape contemporary and future communities facilitates knowledge-based environmental management. In marine ecosystems, one of the most important processes is the supply of new recruits into a population. Here, we investigated spatiotemporal variability in coral recruitment at 15 reefs throughout the Dampier Archipelago, north-western Australia between 2015 and 2017 and identified the best environmental predictors for coral recruitment patterns over this period. Large differences in recruitment were observed among years with the average density of recruits increasing by 375% from 0.017 recruits cm−2 in 2015 to 0.059 recruits cm−2 in 2017. Despite differences in recruitment among years, the rank order of coral recruit density among reefs remained similar among years, suggesting that spatial variation in recruitment within the Dampier Archipelago is partly deterministic and predictable. The density of coral recruits was best explained by percent cover of live corals at both local (within 5 m) and meso-scales (within 15 km), water turbidity and an oceanographic model that predicted larval dispersal. The highest density of coral recruits (~0.13 recruits cm−2 or 37 recruits per tile) occurred on reefs within sub-regions (15 km) with greater than 35% coral cover, low to moderate turbidity (KD490 < 0.2) and moderate to high modelled predictions of larval dispersal. Our results demonstrate that broad-scale larval dispersal models, when combined with local metrics of percent hard coral cover and water turbidity, can reliably predict the relative abundance of coral recruits over large geographical areas and thus can identify hotspots of recruit abundance and potential recovery following environmental disturbances; information that is essential for effective management of coral reefs

The maximally entangled symmetric state in terms of the geometric measure

The geometric measure of entanglement is investigated for permutation symmetric pure states of multipartite qubit systems, in particular the question of maximum entanglement. This is done with the help of the Majorana representation, which maps an n qubit symmetric state to n points on the unit sphere. It is shown how symmetries of the point distribution can be exploited to simplify the calculation of entanglement and also help find the maximally entangled symmetric state. Using a combination of analytical and numerical results, the most entangled symmetric states for up to 12 qubits are explored and discussed. The optimization problem on the sphere presented here is then compared with two classical optimization problems on the S^2 sphere, namely Toth's problem and Thomson's problem, and it is observed that, in general, they are different problems.Comment: 18 pages, 15 figures, small corrections and additions to contents and reference

The oceanography and marine ecology of Ningaloo, a world heritage area

The Ningaloo coast of north-western Australia (eastern Indian Ocean) hosts one of the world’s longest and most extensive fringing coral reef systems, along with globally significant abundances of large marine fauna such as whale sharks. These characteristics – which have contributed to its inscription on the World Heritage list – exist because of the unique climatic, geomorphologic and oceanographic conditions. The region is hot and arid, so runoff of water from land is low, facilitating clear water that allows corals to grow close to the shore. The poleward-flowing Leeuwin Current is an important influence, bringing warm water and generally suppressing coastal upwelling. During the austral summer, strong southerly winds generate the equatorward-flowing Ningaloo Current on the inner shelf – this current facilitates sporadic upwelling events that enhance concentrations of nutrients, which in turn enhance pelagic primary productivity that supports the reef’s biota. The coast has experienced several marine heatwaves since 2011 that have caused mortality of corals and probably seagrass, albeit relatively less than elsewhere along the coast. Wind-generated surface waves break over the fringing reef crest, causing cooling currents that tend to dampen warming – although this mechanism seems not to have prevented some areas from experiencing damaging heat, and corals in places that do not receive the wave-generated currents have experienced substantial mortality. Herbivores, from fish to green turtles, are abundant, and in the lagoon, extensive stands of large brown algae provide an important habitat for newly recruited fish. There has been a decline in abundance of some fish. Predictions of future pressures include a weaker but more variable Leeuwin Current and increased human use. The ability of Ningaloo’s ecosystems to withstand growing pressures will depend partly on the rate and magnitude of global warming but also on actions that manage local pressures from increasing human use. These actions will rely on continued science to provide the evidence needed to identify the pressures, the changes they create and the ways that we can mitigate them

Chapter 4 The Oceanography and Marine Ecology of Ningaloo, A World Heritage Area

The Ningaloo coast of north-western Australia (eastern Indian Ocean) hosts one of the world’s longest and most extensive fringing coral reef systems, along with globally-significant abundances of large marine fauna such as whale sharks. These characteristics — which have contributed to its inscription on the World Heritage list — exist because of the unique climatic, geomorphologic and oceanographic conditions. The region is hot and arid, so runoff of water from land is low, facilitating clear water that allows corals to grow close to the shore. The poleward-flowing Leeuwin Current is an important influence, bringing warm water and generally suppressing coastal upwelling. During the austral summer, strong southerly winds generate the equatorward-flowing Ningaloo Current on the inner shelf — this current facilitates sporadic upwelling events that enhance concentrations of nutrients, which in turn enhances pelagic primary productivity that supports the reef’s biota. The coast has experienced several marine heatwaves since 2011 that have caused mortality of corals, and probably seagrass, albeit relatively less than elsewhere along the coast. Wind-generated surface waves break over the fringing reef crest, causing cooling currents that tend to dampen warming — although this mechanism seems not to have prevented some areas from experiencing damaging heat, and corals in places that do not experience the wave-generated currents have experienced substantial mortality. Herbivores, from fish to green turtles, are abundant, and in the lagoon extensive stands of large brown algae provide an important habitat for newly-recruited fish. There has been a decline in abundance of some fish. Predictions of future pressures include a weaker but more variable Leeuwin Current, and increased human use. The ability of Ningaloo’s ecosystems to withstand growing pressures will depend partly on the rate and magnitude of global warming, but also on actions that manage local pressures from increasing human use. These actions will rely on continued science to provide the evidence needed to identify the pressures, the changes they create and the ways that we can mitigate them

Beliefs and practices of patients with advanced cancer: implications for communication

The aim of this study was to investigate the beliefs that patients with advanced cancer held about the curability of their cancer, their use of alternatives to conventional medical treatment, and their need to have control over decisions about treatment. Of 149 patients who fulfilled the criteria for participation and completed a self-administered questionnaire, 45 patients (31%) believed their cancer was incurable, 61 (42%) were uncertain and 39 (27%) believed their cancer was curable. The index of need for control over treatment decisions was low in 53 patients (35.6%) and high in only 17 patients (11.4%). Committed users of alternatives to conventional medical treatments were more likely to believe that their cancer was curable (

Exploring the predation of UK bumblebees (Apidae, Bombus spp.) by the invasive pitcher plant Sarracenia purpurea: examining the effects of annual variation, seasonal variation, plant density and bumblebee gender

Invasive carnivorous plant species can impact the native invertebrate communities on which they prey. This article explores the predation of native UK bumblebees (Bombus spp.) by the invasive pitcher plant species Sarracenia purpurea and discusses the potential effect of S. purpurea on native bumblebees. Specifically, it evaluates whether the extent to which bumblebees are captured varies (i) over successive years, (ii) across June and July, (iii) with density of distribution of pitchers or (iv) with bumblebee gender. Pitcher contents were examined from an established population of Sarracenia purpurea growing in Dorset, UK. Results show that the total extent to which bumblebees were captured differed over the years 2012–2014 inclusive. A 1-year study in 2013 showed that more bumblebees were caught in July than in June and more bumblebees were captured when pitchers grew at high density. Results from 2013 also showed that more pitchers caught more than one bumblebee than would be expected based on a normal probability distribution and that this phenomenon affects female and male bumblebees equally. We discuss possible reasons for these results including that the bumblebees may be using S. purpurea as a resource. Further work is required to establish the exact underpinning mechanisms and the relative roles of plant and bumblebee behaviour within the relationship. Such interaction complexity may have consequences for consideration in invasive carnivorous plant management