Endurance at intermediate swimming speeds of Atlantic mackerel, Scomber scombrus L., herring, Clupea harengus L., and saithe, Pollachius virens L.

We describe the isolation and identification of di-n-hexyl phthalate, a new marine pollutant found in Atlantic herring (Clupea harengus harengus) and Atlantic mackerel (Scomber scombrus). This compound was isolated from extracted lipids by a combination of gel permeation, high performance liquid and column chromatography, and selective precipitation of impurities. Conclusive proof of its structure was obtained from gas chromatographic–mass spectrometric analysis and proton nuclear magnetic resonance spectroscopy. The concentrations of di-n-hexyl phthalate (17–27 μg/g wet weight), which is not a major industrial phthalic acid ester, far exceeded those of dibutyl and di-2-ethylhexyl phthalates, the major industrial phthalic acid esters. Thus the possibility of selective bioaccumulation of DHP in herring and mackerel was indicated. This finding is important in view of the paucity of toxicological information concerning this compound.Key words: phthalic acid ester, di-n-hexyl phthalate (DHP), analysis, mackerel, herring, marine fish, pollution

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Quantitative molecular detection of larval Atlantic herring (Clupea harengus) in stomach contents of Atlantic mackerel (Scomber scombrus) marks regions of predation pressure

Scientific Reports ◽

10.1038/s41598-021-84545-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Bridie Jean Marie Allan ◽

Jessica Louise Ray ◽

Maik Tiedemann ◽

Valeriya Komyakova ◽

Frode Vikebø ◽

...

Keyword(s):

Early Life ◽

Molecular Detection ◽

Stomach Contents ◽

Early Life History ◽

Predation Pressure ◽

Clupea Harengus ◽

Atlantic Herring ◽

Atlantic Mackerel ◽

Life History Stages ◽

Scomber Scombrus

AbstractMortality rates in the early life-history stages of fishes are generally high yet identifying the causes remain unclear. Faltering recruitment rates of Atlantic herring (Clupea harengus) in the Norwegian Sea indicate a need to identify which mortality factors influence larval herring survival. Previous research suggests that increased predation pressure by Atlantic mackerel (Scomber scombrus) may contribute to the disconnect between spawning stock biomass and recruitment. To quantify the contribution of predation pressure by Atlantic mackerel to herring larval mortality, two research cruises were conducted within a probable “hot spot” (67–72° N) for intensified mackerel predation based on particle drift simulations. Mackerel stomach contents were analysed for herring larvae content using droplet digital polymerase chain reaction (ddPCR) with a quantitative molecular detection assay specific for herring. The ddPCR results demonstrate clear predation by mackerel on herring larvae and also suggest that the alternative use of visual examination may give misleading results. Our results show that mackerel should be considered a potentially important predator on herring larvae. The quantitative molecular assay presented here shows great promise as an efficient and specific tool to correctly identify and quantify predation pressure on early life-history stages of fishes.

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Routine respiration rates of Atlantic mackerel, Scomber scombrus L., and herring, Clupea harengus L., at low activity levels

Journal of Fish Biology ◽

10.1111/j.1095-8649.1993.tb00314.x ◽

1993 ◽

Vol 42 (1) ◽

pp. 149-151 ◽

Cited By ~ 11

Author(s):

A. D. F. Johnstone ◽

C. S. Wardle ◽

S. M. Almatar

Keyword(s):

Clupea Harengus ◽

Activity Levels ◽

Atlantic Mackerel ◽

Scomber Scombrus ◽

Respiration Rates ◽

Low Activity

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Changes in weight-at-length and size-at-age of mature Northeast Atlantic mackerel (Scomber scombrus) from 1984 to 2013: effects of mackerel stock size and herring (Clupea harengus) stock size

ICES Journal of Marine Science ◽

10.1093/icesjms/fsv142 ◽

2015 ◽

Vol 73 (4) ◽

pp. 1255-1265 ◽

Cited By ~ 16

Author(s):

Anna H. Olafsdottir ◽

Aril Slotte ◽

Jan Arge Jacobsen ◽

Guðmundur J. Oskarsson ◽

Kjell R. Utne ◽

...

Keyword(s):

Prey Availability ◽

Somatic Growth ◽

Recent Decade ◽

Clupea Harengus ◽

Negative Effects ◽

Norwegian Sea ◽

Stock Size ◽

Northeast Atlantic ◽

Atlantic Mackerel ◽

Scomber Scombrus

Abstract Weight-at-length and length-/weight-at-age were analysed for mature 3- to 8-year-old Northeast Atlantic mackerel (Scomber scombrus; n= 26 084) collected annually in autumn (September and October) at the end of the annual feeding season during 1984–2013 in the northern North Sea. The age range represented 92% of the mackerel stock size (age 3+). During the most recent decade, mackerel length- and weight-at-age continually declined. In 2013, the average mackerel was 3.7 cm shorter and weighed 175 g less than the average individual in 2002. Individual weight-at-length, demonstrating annual summer feeding success, continually declined during the most recent 5 years, whereas somatic growth of cohorts aged 3–8 continually declined for the last 11 of 25 cohorts investigated. Growth of the latest cohort was 34% of the maximum cohort growth recorded. Both weight-at-length and cohort growth were negatively affected by mackerel stock size and Norwegian spring-spawning herring (Clupea harengus) stock size (weight-at-length: r2 = 0.89; growth (length): r2 = 0.68; growth (weight): r2 = 0.78), while temperature was not significant. Conspecific density-dependence was most likely mediated via intensified competition associated with greater mackerel density. Negative effects of herring were likely mediated by exploitative competition for shared food resources rather than direct competition due to limited spatio-temporal overlap between mackerel and herring during the feeding season. Herring begin their seasonal feeding migration at least a month before mackerel; therefore, herring consumption influences prey availability for the later-arriving mackerel. Record low mackerel growth and negative effects of mackerel and herring stock size suggest that the carrying capacity of the Norwegian Sea and adjacent areas for plankton-feeding fish stocks have been reached. However, compounding effects of a less productive Norwegian Sea during the 30-year period cannot be excluded.

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