Ninety juvenile yellowfin bream Acanthopagrus australis were angled from holding tanks, allowed to ingest nickel-plated, carbon-steel J-hooks and released (with their lines cut) into individual experimental tanks during 2 experiments in order to assess their (1) long-term (up to 105 d) health, mortality and rate of hook ejection and (2) short-and medium-term (< 42 d) temporal changes in health during hook ingestion. Equal numbers of control fish were scooped from holding tanks and similarly monitored in experimental tanks. Of 20 hook-ingested fish released during Expt 1, 3 died within 8 d, providing a non-significant mortality of 15%. Between Day 6 and Day 56 post-release, 13 of the surviving individuals ejected their hooks, which were typically oxidized to about 94% of their original weight and often broken into 2 pieces. At Day 105, there were no significant differences between the 20 control and 17 hook-ingested/-ejected fish in terms of their ability to digest and assimilate food (measured as changes in apparent digestibility coefficients), stress (measured as concentrations of plasma cortisol and glucose) or of morphological parameters that included weight (Wt) and maximum height (MH), maximum width (MW) and maximum girth (MG). During Expt 2, 3 individuals that still contained ingested hooks and 3 controls were sampled on each of 9 occasions between Day 3 and Day 42 post-release. All fish were sampled for blood cortisol and glucose and were then euthanized before being weighed and measured for total length (TL), MH, MW and MG. Hook-ingested individuals were also X-rayed to determine the position and orientation of hooks. There were no significant differences in plasma glucose between hook-ingested and control fish. Irrespective of the treatment of fish, concentrations of cortisol were elevated on some sampling occasions, indicating variable, acute stress. The MH and MG of fish were not significantly different between groups. Significant differences were detected for MG and Wt, with hook-ingested fish having weights similar to those of the control fish but a relatively greater MW (owing to stomach distension from ingested hooks) until 2 wk post-release, after which both morphological parameters generally declined. There was no significant temporal progression of hooks in the stomach of treatment fish; however, some hooks reorientated to positions that may have precluded passage along the digestive tract. We conclude that, for the J-hooks examined, cutting the line is an appropriate strategy that results in the greater majority of released hook-ingested yellowfin bream surviving with minimal negative long-term effects. KEY WORDS: Acanthopagrus australis · Catch-and-release · Hook mortality · Hook ingestionResale or republication not permitted without written consent of the publisher
Samples of 16 key fish species targeted by oceanic prawn trawlers and oceanic and estuarine beach seiners in southeastern Australia were measured for up to 10 morphological dimensions that included: total (Wt) and eviscerated weights (EWt); total (TL), fork (FL), natural (NL), standard (SL), dorsal standard (DSL), and anal standard lengths (ASL); and maximum body height (MH), width (MW), and girth (MG). All partial lengths were indexed against TL to provide linear relationships and, where there were sufficient data, tested for intra-specific sexual dimorphism. Nearly all species that were sexed demonstrated at least some morphological divergence, and especially for transverse measures; probably owing to different reproductive conditions. Sex-specific or combined regressions of DSL and ASL and transverse measures versus TL were used to identify the most appropriate: (1) partial length for compliance purposes; and (2) mesh sizes and configurations for the different fishing gears M05052;
Five species of calcified hydroids occur in shallow waters along the Brazilian coast: four milleporids –Millepora alcicornis Linnaeus, Millepora braziliensis Verrill, Millepora nitida Verrill, and a new species, Millepora laboreli – and one stylasterid – Stylaster roseus (Pallas). Compared to the scleractinian corals, the calcified hydroids of Brazil have received little attention. Nevertheless, Milleporidae are an important component of Brazilian reefs, with colonies that can reach up to 2 m in diameter. Among the aspects that have been studied for Millepora spp, their distributions and skeletal morphometries are the most distinctive. Due to their complex taxonomy, several morphometric characters have been used to facilitate their identification. Molecular systematics has also been used as a complementary technique to traditional taxonomic tools. Other aspects of Brazilian Millepora spp, such as their nematocysts, medusae and ecology, have received less attention; nevertheless, the few existing studies reveal several remarkable features of this genus. Comprehensive studies of Brazilian stylasterids are still lacking.
Purpose Blood flow to skeletal muscles and removal of metabolic by-products during a sport climb are essential to optimise performance and recovery. New Zealand blackcurrant 2 (NZBC) extract enhanced blood flow and performance in other exercise modalities. We examined the effect of NZBC extract on sport climbing performance and recovery. Methods The study employed a double-blind, randomized, cross-over design. Male sport climbers (n=18, age 24±6 yrs, height 179±6 cm, mass 71.4±7.8 kg, French grade 6a-8b) undertook 7 days supplementation of NZBC extract (600 mg•day-1 CurraNZ™ containing 210 mg anthocyanins) or a placebo (PL). Climbing ability was assessed through hang time (HT), pull-ups and total climbing time (TCT) in 3 intermittent climbing bouts on a Treadwall M6 rotating climbing wall to exhaustion with 20 min recovery between climbs. Heart rate (HR), blood lactate (BL), forearm girth (FG) and hand grip strength (HGS) were recorded. Results NZBC extract had no effect on pull-ups but provided a trend for higher HT and significantly improved TCT (+23%) compared to PL (-11%) over 3 climbs. HR, BL, FG and HGS all indicated that 20 minutes was insufficient for physiological recovery between the 3 climbing bouts indicating accumulative fatigue regardless of condition. Conclusion Despite indices of progressive fatigue across 3 bouts of climbing, NZBC extract facilitated not only a maintenance of TCT but an improved climbing endurance as compared with the PL condition. Blackcurrant anthocyanin-derived metabolites seems to affect physiological responses that facilitate sport climbing performance.
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