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Spatial segregation within the spawning migration of North Eastern Atlantic mackerel (Scomber scombrus) as indicated by juvenile growth patterns.

Jansen T, Campbell A, Brunel T, Worsøe Clausen L - PLoS ONE (2013)

Bottom Line: A similar significant relationship was found between the growth in the first year (derived from the otolith inner winter ring) and latitude for adult mackerel spawning between 44°N (Bay of Biscay) and 54°N (west of Ireland).No such relationship was found in mackerel spawning at more northerly latitudes, possibly as a consequence of increased spatial mixing in a more energetic regime with stronger currents.This study provides previously lacking support for spawning segregation behaviour among North East Atlantic mackerel--an important step towards understanding the migratory behaviour of mackerel and hence the spatiotemporal distribution dynamics around spawning time.

View Article: PubMed Central - PubMed

Affiliation: DTU AQUA-National Institute of Aquatic Resources, Technical University of Denmark, Charlottenlund, Denmark. Tej@aqua.dtu.dk

ABSTRACT
A comparison of growth data (fish length) with latitude shows that southern juvenile mackerel attain a greater length than those originating from further north before growth ceases during their first winter. A similar significant relationship was found between the growth in the first year (derived from the otolith inner winter ring) and latitude for adult mackerel spawning between 44°N (Bay of Biscay) and 54°N (west of Ireland). These observations are consistent with spatial segregation of the spawning migration; the further north that the fish were hatched, the further north they will tend to spawn. No such relationship was found in mackerel spawning at more northerly latitudes, possibly as a consequence of increased spatial mixing in a more energetic regime with stronger currents. This study provides previously lacking support for spawning segregation behaviour among North East Atlantic mackerel--an important step towards understanding the migratory behaviour of mackerel and hence the spatiotemporal distribution dynamics around spawning time.

Show MeSH
Mean body length of mackerel at the end of the first growth season (January-March) by latitude.95% confidence interval of the fitted model is indicated by dashed lines. Data from 44–54°N.
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pone-0058114-g003: Mean body length of mackerel at the end of the first growth season (January-March) by latitude.95% confidence interval of the fitted model is indicated by dashed lines. Data from 44–54°N.

Mentions: Inspection of the model residuals in both growth-latitude models revealed that the negative correlations were mainly evident from 44°N to around 54°N (Figure S2, S3). In order to explore this spatial pattern, we repeated the modelling steps separately for two geographical regions: 44°N –54°N and 54°N –61.2°N. While no significant terms were found in the northern models (p>0.05), we again found latitude to be the only significant term in the southern models (Tables 1, 2, Figure 3, 4). Latitude was negatively correlated with body size and L1 with an estimated decrease of 9±5% and 10±3% over the 8.5° from the Bay of Biscay to west of Ireland. The residuals of both models were normal distributed (Anderson-Darling normality test: p>0.05) and do not display any distinct patterns.


Spatial segregation within the spawning migration of North Eastern Atlantic mackerel (Scomber scombrus) as indicated by juvenile growth patterns.

Jansen T, Campbell A, Brunel T, Worsøe Clausen L - PLoS ONE (2013)

Mean body length of mackerel at the end of the first growth season (January-March) by latitude.95% confidence interval of the fitted model is indicated by dashed lines. Data from 44–54°N.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3585244&req=5

pone-0058114-g003: Mean body length of mackerel at the end of the first growth season (January-March) by latitude.95% confidence interval of the fitted model is indicated by dashed lines. Data from 44–54°N.
Mentions: Inspection of the model residuals in both growth-latitude models revealed that the negative correlations were mainly evident from 44°N to around 54°N (Figure S2, S3). In order to explore this spatial pattern, we repeated the modelling steps separately for two geographical regions: 44°N –54°N and 54°N –61.2°N. While no significant terms were found in the northern models (p>0.05), we again found latitude to be the only significant term in the southern models (Tables 1, 2, Figure 3, 4). Latitude was negatively correlated with body size and L1 with an estimated decrease of 9±5% and 10±3% over the 8.5° from the Bay of Biscay to west of Ireland. The residuals of both models were normal distributed (Anderson-Darling normality test: p>0.05) and do not display any distinct patterns.

Bottom Line: A similar significant relationship was found between the growth in the first year (derived from the otolith inner winter ring) and latitude for adult mackerel spawning between 44°N (Bay of Biscay) and 54°N (west of Ireland).No such relationship was found in mackerel spawning at more northerly latitudes, possibly as a consequence of increased spatial mixing in a more energetic regime with stronger currents.This study provides previously lacking support for spawning segregation behaviour among North East Atlantic mackerel--an important step towards understanding the migratory behaviour of mackerel and hence the spatiotemporal distribution dynamics around spawning time.

View Article: PubMed Central - PubMed

Affiliation: DTU AQUA-National Institute of Aquatic Resources, Technical University of Denmark, Charlottenlund, Denmark. Tej@aqua.dtu.dk

ABSTRACT
A comparison of growth data (fish length) with latitude shows that southern juvenile mackerel attain a greater length than those originating from further north before growth ceases during their first winter. A similar significant relationship was found between the growth in the first year (derived from the otolith inner winter ring) and latitude for adult mackerel spawning between 44°N (Bay of Biscay) and 54°N (west of Ireland). These observations are consistent with spatial segregation of the spawning migration; the further north that the fish were hatched, the further north they will tend to spawn. No such relationship was found in mackerel spawning at more northerly latitudes, possibly as a consequence of increased spatial mixing in a more energetic regime with stronger currents. This study provides previously lacking support for spawning segregation behaviour among North East Atlantic mackerel--an important step towards understanding the migratory behaviour of mackerel and hence the spatiotemporal distribution dynamics around spawning time.

Show MeSH