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Concentrations of 11 trace elements in three tissues of porbeagle shark Lamna nasus (n = 33) were determined. The maximum observed concentrations of Cd and Pb in muscle were 0.04 and 0.01 mg kg − 1 , respectively, and all muscle samples were below European seafood limits for these metals. Hg concentrations in either the red or white muscle that exceeded European regulations for seafood were observed in one-third of specimens. Hg concentration, however, increased with length, and all fish > 195 cm had concentrations > 1.0 mg kg − 1 , with a maximum observed value of 2.0 mg kg − 1 . Concentrations of Fe and Cu were, on average, 9.7 and 10 times higher in red muscle than in nearby white muscle, respectively. Mn, Zn, As and Se were also found in significantly higher concentrations in red muscle than in white muscle. [ABSTRACT FROM AUTHOR]

The North-East Atlantic porbeagle (Lamna nasus) population has declined dramatically over the last few decades and is currently classified as 'Critically Endangered'. As long-lived, apex predators, they may be vulnerable to bioaccumulation of contaminants. In this study organohalogen compounds and trace elements were analysed in 12 specimens caught as incidental bycatch in commercial gillnet fisheries in the Celtic Sea in 2011. Levels of organohalogen contaminants were low or undetectable (summed CB and BDE concentrations 0.04-0.85mgkg−1wet weight). A notably high Cd concentration (7.2mgkg−1wet weight) was observed in one mature male, whereas the range observed in the other samples was much lower (0.04-0.26mgkg−1wet weight). Hg and Pb concentrations were detected only in single animals, at 0.34 and 0.08mgkg−1wet weight, respectively. These contaminant levels were low in comparison to other published studies for shark species. [ABSTRACT FROM AUTHOR]

The article discusses a study which measured the thermal experience of several adult Atlantic cod from different stocks in the northeast Atlantic using electronic tags. Data from the study showed that cod is an adaptable and tolerant species capable of surviving and growing in a wide range of temperate marine climates. It was demonstrated that the total thermal niche of the species ranged from -1.5 to 19 degrees centigrade, which was narrower during the spawning period. It also concluded that their growth rates increased with temperature.