Feeding of captive, tropical carcharhinid sharks from the Embley River estuary, northern Australia

Twenty carcharhinid sharks of 3 species were fed pilchards at different frequencies to examine feeding-growth relationships. These results are among the first in Australia on food intake and growth of wild-caught juvenile and sub-adult carcharhinids held in captivity. Mean consumption rates (±SE) for all feeding rations were 2.91% (±0.28) body weight per day (BWD) for Carcharhinus dussumieri, 3.44% (±0.40) BWD for C. tilstoni and 3.35% (±0.34) BWD for Negaprion acutidens. N. acutidens had the highest consumption rate of 5.02% BWD at 2 feeds d-1. Highest mean growth rates were 0.78% (±0.11) BWD for C. dussumieri, 1.34% BWD (±0.54) for C. tilstoni and 1.12% (n = 1) BWD for N. acutidens. Maintenance ration estimates were 1.29% BWD for C. dussumieri, 1.31% BWD for N. acutidens, and 2.06% BWD for C. tilstoni. These are similar to literature estimates. High consumption rates did not always translate directly to high growth rates

Genetic population structure of red snappers (Lutjanus malabaricus Bloch & Schneider, 1801 and Lutjanus erythropterus Bloch, 1790) in central and eastern Indonesia and northern Australia

The genetic population structure of red snapper Lutjanus malabaricus and Lutjanus erythropterus in eastern Indonesia and northern Australia was investigated by allozyme electrophoresis and sequence variation in the control region of mtDNA. Samples were collected from eight sites in Indonesia and four sites in northern Australia for both species. A total of 13 allozyme loci were scored. More variable loci were observed in L. malabaricus than in L. erythropterus. Sequence variation in the control region (left domain) of the mitochondrial genome was assessed by RFLP and direct sequencing. MtDNA haplotype diversity was high (L. erythropterus, 0.95 and L. malabaricus, 0.97), as was intraspecific sequence divergence, (L. erythropterus, 0.0-12.5% and L. malabaricus, 0.0-9.5%). The pattern of mtDNA haplotype frequencies grouped both species into two broad fisheries stocks with a genetic boundary either between Kupang and Sape (L. malabaricus) or between Kupang and Australian Timor Sea (L. erythropertus). The allozyme analyses revealed similar boundaries for L. erythropterus. Seven allozymes stocks compared to two mtDNA stocks of L. malabaricus including Ambon, which was not sampled with mtDNA, however, were reported. Possible reasons for differences in discrimination between the methods include: i) increased power of multiple allozyme loci over the single mtDNA locus, ii) insufficient gene sampling in the mtDNA control region and iii) relative evolutionary dynamics of nuclear (allozyme loci) and mitochondrial DNA in these taxa. Allozyme and haplotype data did not distinguish separate stocks among the four Australian locations nor the central Indonesian (Bali and Sape locations) for both L. malabaricus and L. erythropterus

The effectiveness of fish and shrimp trawls for sampling fish communities in tropical Australia

Catches of fish in a Frank and Bryce fish trawl during the day and in a Florida Flyer shrimp trawl at night were compared over 2 years (1992, 1993). The effectiveness of a Frank and Bryce demersal trawl as a sampling tool for demersal fish communities was assessed from 122 stations in the far northern section of the Great Barrier Reef. Day-time and night-time catches of the Frank and Bryce net were compared to identify diurnal and nocturnal species. Of a total of 259 species caught, 138 were caught both during the day and at night. An analysis of variance was used to identify species that were caught exclusively or in greater biomass during the day or night; 17 species (mainly small apogonids and mullids) were significantly nocturnal and one (a leiognathid) was significantly diurnal. The overall catch rate of the fish trawl during the day was 395.8 kg h−1 (s.e. 141.3) and that of the shrimp trawl at night was 28.0 kg h−1 (s.e. 1.7). A total of 340 species was caught by both types of net—the fish trawler caught 236 species, the shrimp trawler 243, and 141 were common to both trawl types. An analysis of variance was used to help identify species that were caught in greater biomass by either trawl. Fifty-eight fish species each had a greater biomass in the fish trawl than in the shrimp trawls, for 60 species it was the reverse and for 32 species there was no difference. The fish caught only by the fish trawl were mainly pelagic species (mackerels, carangids) or specimens of large species (lutjanids, sharks and rays), while the fish caught only by the shrimp trawl were small benthic species (apogonids, platycephalids, scorpaenids and flatfish). Over 80% of the fish caught by both nets were small (< 30 cm SL). The length-frequency distributions of only seven species differed significantly between fish and shrimp trawl catches, with the shrimp trawl generally catching the smaller component. No large commercially or recreationally important species of reef fish were caught by the shrimp trawl. The results of this study indicate that each type of trawl net will catch different species and, where they catch the same species, they catch different numbers, sizes and weights. Neither gear type can be used on its own for an adequate description of the fish community

Accelerated surgery versus standard care in hip fracture (HIP ATTACK) : an international, randomised, controlled trial

Background: Observational studies have suggested that accelerated surgery is associated with improved outcomes in patients with a hip fracture. The HIP ATTACK trial assessed whether accelerated surgery could reduce mortality and major complications. Methods: HIP ATTACK was an international, randomised, controlled trial done at 69 hospitals in 17 countries. Patients with a hip fracture that required surgery and were aged 45 years or older were eligible. Research personnel randomly assigned patients (1:1) through a central computerised randomisation system using randomly varying block sizes to either accelerated surgery (goal of surgery within 6 h of diagnosis) or standard care. The coprimary outcomes were mortality and a composite of major complications (ie, mortality and non-fatal myocardial infarction, stroke, venous thromboembolism, sepsis, pneumonia, life-threatening bleeding, and major bleeding) at 90 days after randomisation. Patients, health-care providers, and study staff were aware of treatment assignment, but outcome adjudicators were masked to treatment allocation. Patients were analysed according to the intention-to-treat principle. This study is registered at ClinicalTrials.gov (NCT02027896). Findings: Between March 14, 2014, and May 24, 2019, 27 701 patients were screened, of whom 7780 were eligible. 2970 of these were enrolled and randomly assigned to receive accelerated surgery (n=1487) or standard care (n=1483). The median time from hip fracture diagnosis to surgery was 6 h (IQR 4\u20139) in the accelerated-surgery group and 24 h (10\u201342) in the standard-care group (p&lt;0\ub70001). 140 (9%) patients assigned to accelerated surgery and 154 (10%) assigned to standard care died, with a hazard ratio (HR) of 0\ub791 (95% CI 0\ub772 to 1\ub714) and absolute risk reduction (ARR) of 1% ( 121 to 3; p=0\ub740). Major complications occurred in 321 (22%) patients assigned to accelerated surgery and 331 (22%) assigned to standard care, with an HR of 0\ub797 (0\ub783 to 1\ub713) and an ARR of 1% ( 122 to 4; p=0\ub771). Interpretation: Among patients with a hip fracture, accelerated surgery did not significantly lower the risk of mortality or a composite of major complications compared with standard care. Funding: Canadian Institutes of Health Research