Water temperature affects somatic growth, body condition and oxygen and carbon otolith isotopes of stout whiting (Sillago robusta).

Ocean warming will continue to affect the growth, body condition and geographic distributions of marine fishes and understanding these effects is an urgent challenge for fisheries research and management. Determining how temperature is recorded in fish otolith carbonate, provides an additional chronological tool to investigate thermal histories, preferences and patterns of movement throughout an individual's life history. The influence of three water temperature treatments (22°C, 25°C, and 28°C) on hatchery-reared juvenile stout whiting, Sillago robusta, was tested using a controlled outdoor mesocosm system. Fish were measured for change in length and weight, and body condition was determined using bioelectrical impedance analysis. Sagittal otoliths were analysed for stable oxygen (δ18Ootolith) and carbon (δ13Cotolith) isotopes via isotope ratio mass spectrometry. Whiting kept at 22°C were significantly smaller and had diminished body condition compared to fish in 25°C and 28°C, which did not significantly differ from each other. The δ18O otolith values of stout whiting demonstrated a negative temperature-dependent fractionation relationship which was similar in slope but had a different intercept to the relationships reported for inorganic aragonite and other marine fish species. The δ13C otolith values also showed a negative relationship with water temperature, and the calculated proportion of metabolic carbon M in otoliths differed between fish reared in the coolest (22°C) and warmest (28°C) temperature treatments. Overall, the results suggest that stout whiting may have reached an upper growth threshold between 25°C and 28°C, and that growth and body condition may be optimised during warmer seasons and toward the northerly regions of their distribution. Otolith oxygen thermometry shows promise as a natural tracer of thermal life history, and species-specific fractionation equations should be utilised when possible to prevent errors in temperature reconstructions of wild-caught fish.

Fighting and mating success in giant Australian cuttlefish is influenced by behavioural lateralization.

Behavioural lateralization is widespread. Yet, a fundamental question remains, how can lateralization be evolutionary stable when individuals lateralized in one direction often significantly outnumber individuals lateralized in the opposite direction? A recently developed game theory model predicts that fitness consequences which occur during intraspecific interactions may be driving population-level lateralization as an evolutionary stable strategy. This model predicts that: (i) minority-type individuals exist because they are more likely to adopt unpredictable fighting behaviours during competitive interactions (e.g. fighting); and (ii) majority-type individuals exist because there is a fitness advantage in having their biases synchronized with other conspecifics during interactions that require coordination (e.g. mating). We tested these predictions by investigating biases in giant Australian cuttlefish during fighting and mating interactions. During fighting, most male cuttlefish favoured the left eye and these males showed higher contest escalation; but minority-type individuals with a right-eye bias achieved higher fighting success. During mating interactions, most male cuttlefish favoured the left eye to inspect females. Furthermore, most male cuttlefish approached the female's right side during a mating attempt and these males achieved higher mating success. Our data support the hypothesis that population-level biases are an evolutionary consequence of the fitness advantages involved in intraspecific interactions.

A review of the burns caseload of a physician-based helicopter emergency medical service.

OBJECTIVES: The aim of this study was to describe patient demographics, injuries, physiology and interventions performed by retrieval physicians in the care of burns patients in both a pre-hospital and interhospital setting. METHODS: A retrospective review of patient records from a large Australian Helicopter Emergency Medical Service was conducted. Demographics, injury, burn type, physiology and intervention data were extracted into a database for statistical analysis. Basic descriptive statistics were calculated, and patient physiology measures were compared at arrival and destination. RESULTS: A total of 490 burns cases were identified from a 5 year period (January 2010-August 2015). The majority (78.6%) were interhospital transfers conducted by road (49.4%) or helicopter (36.9%). Patients were predominantly men (75.7%) with a median age of 37 years (interquartile range [IQR] 23-50). Median estimated total body surface area burned was 15% (IQR 8.5-20) and 18% (IQR 10-30) in pre-hospital and interhospital groups, respectively; however, retrieval physicians tended to overestimate total body surface area burned in comparison to destination burns units. Flash burn or explosion were the predominant aetiology of burn (49.4%), although the majority (95.3%) of patients had no associated traumatic injuries. Sixty patients were intubated by the Service. Escharotomies were performed on eight occasions resulting in improvement in circulation or ventilation. Overall mortality was 3.7% at 24 h. CONCLUSIONS: The Service cares for 80-100 burns patients annually, a proportion of whom require complex interventions such as intubation and escharotomy, which was performed by retrieval physicians appropriately. Associated traumatic injuries were infrequent in patients who sustained burns from flashes or explosions.

Errors and Predictors of Confidence in Condom Use amongst Young Australians Attending a Music Festival.

Objectives. To determine the confidence and ability to use condoms correctly and consistently and the predictors of confidence in young Australians attending a festival. Methods. 288 young people aged 18 to 29 attending a mixed-genre music festival completed a survey measuring demographics, self-reported confidence using condoms, ability to use condoms, and issues experienced when using condoms in the past 12 months. Results. Self-reported confidence using condoms was high (77%). Multivariate analyses showed confidence was associated with being male (P < 0.001) and having had five or more lifetime sexual partners (P = 0.038). Reading packet instructions was associated with increased condom use confidence (P = 0.011). Amongst participants who had used a condom in the last year, 37% had experienced the condom breaking and 48% had experienced the condom slipping off during intercourse and 51% when withdrawing the penis after sex. Conclusion. This population of young people are experiencing high rates of condom failures and are using them inconsistently or incorrectly, demonstrating the need to improve attitudes, behaviour, and knowledge about correct and consistent condom usage. There is a need to empower young Australians, particularly females, with knowledge and confidence in order to improve condom use self-efficacy.

Asexual propagation of sea anemones that host anemonefishes: implications for the marine ornamental aquarium trade and restocking programs.

Anemonefishes and their host sea anemones form an iconic symbiotic association in reef environments, and are highly sought after in the marine aquarium trade. This study examines asexual propagation as a method for culturing a geographically widespread and commonly traded species of host sea anemone, Entacmaea quadricolor. Two experiments were done: the first to establish whether size or colour morph influenced survival after cutting into halves or quarters; and the second to see whether feeding was needed to maximise survival and growth after cutting. Survival rates were high in both experiments, with 89.3 and 93.8% of the anemones cut in half, and 62.5 and 80.4% cut in quarters surviving in experiments 1 and 2, respectively. Anemones that were cut in half were larger in size, and healed and grew quicker than those cut in quarters. However, even though survival was lower when the individuals were cut in quarters, this treatment produced the greatest number of anemones. Feeding increased oral disc diameter growth and reduced wet weight loss, but did not significantly influence pedal disc diameter. Given that the anemones took up to 56 d to form an off-centre mouth, it is highly likely that feeding may have produced greater effect if the experiment was run for longer. This low technology method of propagation could be used to produce individuals throughout the year and the anemones could then be used to supply the aquarium trade or restock depleted habitats, thus supporting biodiversity conservation in coral reef areas.

Sulfide formation in freshwater sediments, by sulfate-reducing microorganisms with diverse tolerance to salt.

Understanding how sulfate-reducing microbes in freshwater systems respond to added salt, and therefore sulfate, is becoming increasingly important in inland systems where the threat from salinisation is increasing. To address this knowledge gap, we carried out mesocosm studies to determine how the sulfate-reducing microbial community in sediments from a freshwater wetland would respond to salinisation. The levels of inorganic mineral sulfides produced after 6months incubation were measured to determine whether they were in sufficient quantity to be harmful if re-oxidized. Comparative sequence analysis of the dissimilatory sulfite reductase (DSR) gene was used to compare the sulfate-reducing community structure in mesocosms without salt and those incubated with moderate levels of salt. The amount of total S, acid volatile sulfide or chromium-reducible sulfide produced in sediments with 0, 1 or 5gL(-1) added salt were not significantly different. Sediments subjected to 15gL(-1) salt contained significantly higher total S and acid volatile sulfide, and levels were above trigger values for potential harm if re-oxidation occurred. The overall community structure of the sulfate-reducing microbiota (SRM) was explained by the level of salt added to sediments. However, a group of sulfate reducers were identified that occurred in both the high salt and freshwater treatments. These results demonstrate that freshwater sediments contain sulfate reducers with diverse abilities to respond to salt and can respond rapidly to increasing salinity, explaining the observation that harmful levels of acid volatile sulfides can form rapidly in sediments with no history of exposure to salt.

Adaptable night camouflage by cuttlefish.

Cephalopods are well known for their diverse, quick-changing camouflage in a wide range of shallow habitats worldwide. However, there is no documentation that cephalopods use their diverse camouflage repertoire at night. We used a remotely operated vehicle equipped with a video camera and a red light to conduct 16 transects on the communal spawning grounds of the giant Australian cuttlefish Sepia apama situated on a temperate rock reef in southern Australia. Cuttlefish ceased sexual signaling and reproductive behavior at dusk and then settled to the bottom and quickly adapted their body patterns to produce camouflage that was tailored to different backgrounds. During the day, only 3% of cuttlefish were camouflaged on the spawning ground, but at night 86% (71 of 83 cuttlefish) were camouflaged in variations of three body pattern types: uniform (n=5), mottled (n=33), or disruptive (n=34) coloration. The implication is that nocturnal visual predators provide the selective pressure for rapid, changeable camouflage patterning tuned to different visual backgrounds at night.