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O'Toole, A. C., Danylchuk, A. J., Suski, C. D., and Cooke, S. J. 2010. Consequences of catch-and-release angling on the physiological status, injury, and immediate mortality of great barracuda (Sphyraena barracuda) in The Bahamas. – ICES Journal of Marine Science, 67: 1667–1675.Great barracuda (Sphyraena barracuda) are a common marine predatory fish readily captured by anglers (frequently as incidental bycatch while pursuing other gamefish) and are consequently released at high rates. A study was conducted in coastal waters of The Bahamas to evaluate how common angling techniques influence their physiological status, hooking injury, and immediate mortality. Post-angling blood glucose and plasma sodium levels increased with fight-time duration, though lactate levels increased only with longer blood sampling times. Concentrations of plasma chloride and potassium were not influenced by angling duration. We did not observe any differences in injury, bleeding, hook removal, or hooking depth among three types of artificial lure tested. Most fish were hooked in non-critical areas and experienced minimal or no bleeding at the hook site, so immediate mortality upon landing was negligible. Although great barracuda appear to be fairly resilient to physiological stress and injury associated with catch-and-release angling and immediate mortality was insignificant, they typically reside in habitats where post-release predation is possible. As such, efforts should be made to promote careful handling to ensure high rates of survival. [ABSTRACT FROM PUBLISHER]

Tsagarakis, K., Machias, A., Giannoulaki, M., Somarakis, S., and Karakassis, I. 2008. Seasonal and temporal trends in metrics of fish community for otter-trawl discards in a Mediterranean ecosystem. – ICES Journal of Marine Science, 65: 539–550.Trends in discard to marketed ratios, size spectra, diversities, and trophic levels of the demersal fish community were examined using data from a seasonally closed commercial trawl fishery in the eastern Mediterranean Sea (Ionian Sea), over a period of about 10 years. Trends were also examined for the artificial fractions derived from the discarding process (the marketed, the discarded, and the non-marketed clusters of the catch), as well as for the “big” and “small” fractions (defined by the size at which 50% of all specimens were discarded). The ratio of the discarded/marketed catch fluctuated greatly. Two commercial (Merluccius merluccius, and Mullus barbatus) and two non-marketed species (Lepidotrigla cavillone, and Argentina sphyraena) were the characteristic species of the fractions. A declining trend with time was observed for the examined time-series for species richness (S), Margalef’s d, and average taxonomic distinctness (Δ+), whereas the variation in taxonomic distinctness (Λ+) increased. The composition and/or trophic level of discards in relation to the marketed catch seemed to be indicative of the exploitation state of the demersal community: differences between the discarded and marketed fractions were high at the beginning of the fishing season (autumn), but the values of the indices converged at the end of the fishing season (spring). These changes could be attributed to alternative discarding strategies for certain species in response to increased cumulative fishing mortality towards the end of the period. [ABSTRACT FROM PUBLISHER]