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Feeding Ecology of Northeast Atlantic Mackerel, Norwegian Spring-Spawning Herring and Blue Whiting in the Norwegian Sea.

Bachiller E, Skaret G, Nøttestad L, Slotte A - PLoS ONE (2016)

Bottom Line: The Norwegian spring-spawning (NSS) herring (Clupea harengus), blue whiting (Micromesistius poutassou) and Northeast Atlantic (NEA) mackerel (Scomber scombrus) are extremely abundant pelagic planktivores that feed in the Norwegian Sea (NS) during spring and summer.For all the species, feeding incidence increased with decreasing temperature, and for mackerel so did stomach fullness, indicating that feeding activity is highest in areas associated with colder water masses.Significant annual effects on diet composition and feeding-related variables suggested that the three species are able to adapt to different food and environmental conditions.

View Article: PubMed Central - PubMed

Affiliation: Pelagic Fish Research Group, Institute of Marine Research (IMR), PO Box 1870, Nordnes, NO-5817, Bergen, Norway.

ABSTRACT
The Norwegian spring-spawning (NSS) herring (Clupea harengus), blue whiting (Micromesistius poutassou) and Northeast Atlantic (NEA) mackerel (Scomber scombrus) are extremely abundant pelagic planktivores that feed in the Norwegian Sea (NS) during spring and summer. This study investigated the feeding ecology and diet composition of these commercially important fish stocks on the basis of biological data, including an extensive set of stomach samples in combination with hydrographical data, zooplankton samples and acoustic abundance data from 12 stock monitoring surveys carried out in 2005-2010. Mackerel were absent during the spring, but had generally high feeding overlap with herring in the summer, with a diet mainly based on calanoid copepods, especially Calanus finmarchicus, as well as a similar diet width. Stomach fullness in herring diminished from spring to summer and feeding incidence was lower than that of mackerel in summer. However, stomach fullness did not differ between the two species, indicating that herring maintain an equally efficient pattern of feeding as mackerel in summer, but on a diet that is less dominated by copepods and is more reliant on larger prey. Blue whiting tended to have a low dietary overlap with mackerel and herring, with larger prey such as euphausiids and amphipods dominating, and stomach fullness and feeding incidence increasing with length. For all the species, feeding incidence increased with decreasing temperature, and for mackerel so did stomach fullness, indicating that feeding activity is highest in areas associated with colder water masses. Significant annual effects on diet composition and feeding-related variables suggested that the three species are able to adapt to different food and environmental conditions. These annual effects are likely to have an important impact on the predation pressure on different plankton groups and the carrying capacity of individual systems, and emphasise the importance of regular monitoring of pelagic fish diets.

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Related in: MedlinePlus

Average diet composition (mean prey group mg fish-1 weighted by the total estimated abundance per station), in percentages, for mackerel, herring and blue whiting in different water masses in May and July.All sampling years were analysed together (i.e. ‘Dataset1’ in Table 1; all stations in Fig 1). Light grey lines represent the average water mass boundaries during each season. Nst and Nf are the number of stations and fish samples, respectively. Empty stomachs were excluded from this analysis.
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pone.0149238.g004: Average diet composition (mean prey group mg fish-1 weighted by the total estimated abundance per station), in percentages, for mackerel, herring and blue whiting in different water masses in May and July.All sampling years were analysed together (i.e. ‘Dataset1’ in Table 1; all stations in Fig 1). Light grey lines represent the average water mass boundaries during each season. Nst and Nf are the number of stations and fish samples, respectively. Empty stomachs were excluded from this analysis.

Mentions: When diet data from all water masses and years are considered, mackerel and herring had similar diet compositions, with calanoid copepods (especially C. finmarchicus) as the dominant prey item. The ingestion of other groups like appendicularians and euphausiids (which were particularly abundant in herring stomachs in July) was also pronounced in some seasons and years. The blue whiting diet included more larger prey like euphausiids and amphipods (e.g. Themisto spp.), and less copepods than the diet of the two other species (Fig 4).


Feeding Ecology of Northeast Atlantic Mackerel, Norwegian Spring-Spawning Herring and Blue Whiting in the Norwegian Sea.

Bachiller E, Skaret G, Nøttestad L, Slotte A - PLoS ONE (2016)

Average diet composition (mean prey group mg fish-1 weighted by the total estimated abundance per station), in percentages, for mackerel, herring and blue whiting in different water masses in May and July.All sampling years were analysed together (i.e. ‘Dataset1’ in Table 1; all stations in Fig 1). Light grey lines represent the average water mass boundaries during each season. Nst and Nf are the number of stations and fish samples, respectively. Empty stomachs were excluded from this analysis.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4764516&req=5

pone.0149238.g004: Average diet composition (mean prey group mg fish-1 weighted by the total estimated abundance per station), in percentages, for mackerel, herring and blue whiting in different water masses in May and July.All sampling years were analysed together (i.e. ‘Dataset1’ in Table 1; all stations in Fig 1). Light grey lines represent the average water mass boundaries during each season. Nst and Nf are the number of stations and fish samples, respectively. Empty stomachs were excluded from this analysis.
Mentions: When diet data from all water masses and years are considered, mackerel and herring had similar diet compositions, with calanoid copepods (especially C. finmarchicus) as the dominant prey item. The ingestion of other groups like appendicularians and euphausiids (which were particularly abundant in herring stomachs in July) was also pronounced in some seasons and years. The blue whiting diet included more larger prey like euphausiids and amphipods (e.g. Themisto spp.), and less copepods than the diet of the two other species (Fig 4).

Bottom Line: The Norwegian spring-spawning (NSS) herring (Clupea harengus), blue whiting (Micromesistius poutassou) and Northeast Atlantic (NEA) mackerel (Scomber scombrus) are extremely abundant pelagic planktivores that feed in the Norwegian Sea (NS) during spring and summer.For all the species, feeding incidence increased with decreasing temperature, and for mackerel so did stomach fullness, indicating that feeding activity is highest in areas associated with colder water masses.Significant annual effects on diet composition and feeding-related variables suggested that the three species are able to adapt to different food and environmental conditions.

View Article: PubMed Central - PubMed

Affiliation: Pelagic Fish Research Group, Institute of Marine Research (IMR), PO Box 1870, Nordnes, NO-5817, Bergen, Norway.

ABSTRACT
The Norwegian spring-spawning (NSS) herring (Clupea harengus), blue whiting (Micromesistius poutassou) and Northeast Atlantic (NEA) mackerel (Scomber scombrus) are extremely abundant pelagic planktivores that feed in the Norwegian Sea (NS) during spring and summer. This study investigated the feeding ecology and diet composition of these commercially important fish stocks on the basis of biological data, including an extensive set of stomach samples in combination with hydrographical data, zooplankton samples and acoustic abundance data from 12 stock monitoring surveys carried out in 2005-2010. Mackerel were absent during the spring, but had generally high feeding overlap with herring in the summer, with a diet mainly based on calanoid copepods, especially Calanus finmarchicus, as well as a similar diet width. Stomach fullness in herring diminished from spring to summer and feeding incidence was lower than that of mackerel in summer. However, stomach fullness did not differ between the two species, indicating that herring maintain an equally efficient pattern of feeding as mackerel in summer, but on a diet that is less dominated by copepods and is more reliant on larger prey. Blue whiting tended to have a low dietary overlap with mackerel and herring, with larger prey such as euphausiids and amphipods dominating, and stomach fullness and feeding incidence increasing with length. For all the species, feeding incidence increased with decreasing temperature, and for mackerel so did stomach fullness, indicating that feeding activity is highest in areas associated with colder water masses. Significant annual effects on diet composition and feeding-related variables suggested that the three species are able to adapt to different food and environmental conditions. These annual effects are likely to have an important impact on the predation pressure on different plankton groups and the carrying capacity of individual systems, and emphasise the importance of regular monitoring of pelagic fish diets.

Show MeSH
Related in: MedlinePlus