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Forty-nine species (87 samples) of marine macroalgae from eastern Australia were analyzed by GC/MS for the key seafood flavor components 2- and 4-bromophenol, 2,4- and 2,6-dibromophenol, and 2,4, 6-tribromophenol. All five bromophenols were found in 62% of samples, four in 32% of samples, and three in the remaining 6% of samples. 2, 4,6-Tribromophenol was found in all samples and, with few exceptions, was present in the highest concentrations. The total bromophenol content determined on a wet-weight basis varied widely across species from 0.9 ng/g in the green alga Codium fragile to 2590 ng/g in the red alga Pterocladiella capillacea. Species with the highest concentrations of bromophenols were all collected from sites exposed at low tide. The study demonstrates the wide occurrence of bromophenols in marine algae and provides a possible source of such compounds in fish that feed predominantly on ocean plants. The possible effect that dietary marine algae has on the flavor of omnivorous ocean fish is discussed.

Thirty samples of 9 species of prawns (shrimp) harvested from sites along the eastern coast of Australia and 10 samples of two cultivated species were analyzed by GC/MS for the key flavor components, 2- and 4-bromophenol, 2,4- and 2,6-dibromophenol, and 2,4,6-tribromophenol. In the commercially important wild-harvested species, Penaeus plebejus, P. esculentus, and P. latisulcatus, the total bromophenol content was found to vary between 9.5 and 1114 ng/g, while in the major cultivated species, P. monodon, the total bromophenol content was <1 ng/g. Sensory analyses of 10 samples of wild-harvested prawns showed that the meat of these animals had briny, ocean-like, and prawn-like flavors, whereas all five samples of cultivated prawns were described as bland. Furthermore, analysis by GC/MS of the heads (including the gut) and tails of these animals showed that in wild-harvested prawns the average total bromophenol content in the heads was 6.8 times greater than that in the tails; in cultivated animals it was only 3 times greater. These observations support the opinion that bromophenols are derived from components of the diets of these animals. The paper discusses the likely dietary sources of these compounds in Australian prawns and a possible controlled dietary procedure to improve the flavor of cultivated animals. Keywords: Prawns; bromophenols; GC/MS analysis; flavor; sensory analysis; dietary origins

Evidence is accumulating that many marine ectotherms are undergoing rapid changes in their life‐history characteristics. These changes have been variously attributed to fisheries‐induced evolution, inhibited adult growth rate due to oxygen limitation at higher temperatures, and plastic responses to density dependence or changes in ocean productivity. Here, we review the diverse underlying mechanisms by which plastic and evolutionary responses to climate change and fisheries are likely to produce similar life‐history trends in harvested marine ectotherms, leading to faster life‐histories with earlier maturation and smaller adult size‐at‐age. While mechanistically understanding these growth and maturation changes may be difficult, it is becoming clear that changing life‐histories will lead to modified population dynamics, productivity and natural mortality of the affected species. We discuss how the observed and expected life‐history changes could affect the assumptions and uncertainty within single and multispecies models currently used in marine ecosystem management, highlighting that models which allow for dynamic life‐history traits often report significantly different estimates of stock biomass. Given that both climate‐ and harvest‐induced life‐history changes are likely to intensify and possibly amplify each other, there is an urgent need to adequately assess the implications of faster life‐histories for marine ecosystem management. This is especially true for data‐poor stocks, where growth and maturation are not regularly assessed. Targeted monitoring can be used to inform responsive management, but for improved sustainability outcomes, a precautionary approach to management that is robust to life‐history trends is advised.