The distribution and population structure of the bivalve Arctica islandica L. in the North Sea: what possible factors are involved?

The harbour porpoise is seriously depleted and threatened with extinction in the Baltic Sea. It is usually assumed that Baltic porpoises form a separate population unit, although the evidence for this has been disputed lately. Here, a 3-D geometric morphometric approach was employed to test a number of hypotheses regarding population structure of the harbour porpoise in the Baltic region. 277 porpoise skulls from Denmark, Sweden, Finland, Germany and Poland were measured with a suite of 3-D landmarks. Statistical analyses revealed highly significant shape differences between porpoises from the North Sea, Belt Sea and the inner Baltic Sea. A comparison of the directionalities of the shape vectors between these units found differences that cannot be attributed to a general, continual shape trend going from the North Sea to the inner Baltic Sea. These vectors indicate a morphological adaptation to the specific sub-areas. Such adaptation may be the result of the topographic peculiarities of the area with variable topography and shallow waters, e.g. in the Belt Sea porpoises, there may be a greater reliance on benthic and demersal prey. The present results show that isolation by distance alone is an unlikely explanation for the differences found within the Baltic region and thus support previously reported molecular indications of a separate population within the inner Baltic Sea.

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Microgeographical population structure of cod Gadus morhua in the North Sea and west of Scotland: the role of sampling loci and individuals

Marine Ecology Progress Series ◽

10.3354/meps07798 ◽

2009 ◽

Vol 376 ◽

pp. 213-225 ◽

Cited By ~ 38

Author(s):

EE Nielsen ◽

PJ Wright ◽

J Hemmer-Hansen ◽

NA Poulsen ◽

I Monro Gibb ◽

...

Keyword(s):

Population Structure ◽

North Sea ◽

Gadus Morhua ◽

The North ◽

The North Sea

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Population Genetic Structure Is Unrelated to Shell Shape, Thickness and Organic Content in European Populations of the Soft-Shell Clam Mya Arenaria

Genes ◽

10.3390/genes11030298 ◽

2020 ◽

Vol 11 (3) ◽

pp. 298 ◽

Cited By ~ 2

Author(s):

Michele De Noia ◽

Luca Telesca ◽

David L. J. Vendrami ◽

Hatice K. Gokalp ◽

Grégory Charrier ◽

...

Keyword(s):

Population Structure ◽

Genetic Structure ◽

North Sea ◽

Organic Content ◽

Mya Arenaria ◽

Shell Shape ◽

Soft Shell Clam ◽

The North ◽

Soft Shell ◽

The North Sea

The soft-shell clam Mya arenaria is one of the most ancient invaders of European coasts and is present in many coastal ecosystems, yet little is known about its genetic structure in Europe. We collected 266 samples spanning a latitudinal cline from the Mediterranean to the North Sea and genotyped them at 12 microsatellite loci. In parallel, geometric morphometric analysis of shell outlines was used to test for associations between shell shape, latitude and genotype, and for a selection of shells we measured the thickness and organic content of the granular prismatic (PR), the crossed-lamellar (CL) and the complex crossed-lamellar (CCL) layers. Strong population structure was detected, with Bayesian cluster analysis identifying four groups located in the Mediterranean, Celtic Sea, along the continental coast of the North Sea and in Scotland. Multivariate analysis of shell shape uncovered a significant effect of collection site but no associations with any other variables. Shell thickness did not vary significantly with either latitude or genotype, although PR thickness and calcification were positively associated with latitude, while CCL thickness showed a negative association. Our study provides new insights into the population structure of this species and sheds light on factors influencing shell shape, thickness and microstructure.

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A new ΔR value for the southern North Sea and its application in coastal research

Netherlands Journal of Geosciences – Geologie en Mijnbouw ◽

10.1017/njg.2020.19 ◽

2021 ◽

Vol 100 ◽

Author(s):

Dirk Enters ◽

Kristin Haynert ◽

Achim Wehrmann ◽

Holger Freund ◽

Frank Schlütz

Keyword(s):

North Sea ◽

Wadden Sea ◽

Mya Arenaria ◽

Arctica Islandica ◽

Growth Rings ◽

The North ◽

Local Correction ◽

The North Sea ◽

Sea Area ◽

Coastal Research

Abstract Accelerator mass spectrometry (AMS) radiocarbon (14C) dating of Cerastoderma edule (Linnaeus 1767) and Mytilus edulis (Linnaeus 1758) shells sampled in AD 1889 near the island of Wangerooge gave a new local correction factor ΔR of −85 ± 17 14C years for the Wadden Sea area. The value is considerably higher than the available scattered data from the North Sea, which were obtained from pre-bomb growth rings of living Arctica islandica (Linnaeus 1767). This can be explained by the incorporation of 14C-depleted terrestrial carbon into the shell material which compensates the intensified exchange of CO2 between atmosphere and shallow coastal water, e.g. by tidal currents. Additionally, two examples of application of the new ΔR value in coastal research give deeper insights into the dynamics of bivalve shell preservation in the Wadden Sea and the need for further research to clarify the Holocene reintroduction of Mya arenaria (Linnaeus 1758) into European waters.

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Decadal climate variability of the North Sea during the last millennium reconstructed from bivalve shells (Arctica islandica)

The Holocene ◽

10.1177/0959683614530438 ◽

2014 ◽

Vol 24 (7) ◽

pp. 771-786 ◽

Cited By ~ 18

Author(s):

Hilmar A Holland ◽

Bernd R Schöne ◽

Constanze Lipowsky ◽

Jan Esper

Keyword(s):

Climate Variability ◽

North Sea ◽

Last Millennium ◽

Decadal Climate Variability ◽

Arctica Islandica ◽

The North ◽

The North Sea ◽

Decadal Climate ◽

Bivalve Shells

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Genetic population structure of minke whales Balaenoptera acutorostrata from Greenland, the North East Atlantic and the North Sea probably reflects different ecological regions

Marine Ecology Progress Series ◽

10.3354/meps247263 ◽

2003 ◽

Vol 247 ◽

pp. 263-280 ◽

Cited By ~ 14

Author(s):

LW Andersen ◽

EW Born ◽

R Dietz ◽

T Haug ◽

N Øien ◽

...

Keyword(s):

Population Structure ◽

North Sea ◽

Balaenoptera Acutorostrata ◽

East Atlantic ◽

Genetic Population ◽

Ecological Regions ◽

North East ◽

The North ◽

Minke Whales ◽

The North Sea

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Geographical differences in growth rates of Arctica islandica (Mollusca: Bivalvia) from the North Sea and adjacent waters

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315498001076 ◽

1999 ◽

Vol 79 (5) ◽

pp. 907-915 ◽

Cited By ~ 45

Author(s):

R. Witbaard ◽

G.C.A. Duineveld ◽

P.A.W.J. de Wilde

Keyword(s):

Growth Rate ◽

Primary Production ◽

North Sea ◽

Growth Rates ◽

Shell Growth ◽

Geographical Differences ◽

Arctica Islandica ◽

The North ◽

Standard Coefficient ◽

The North Sea

Geographical differences in the shell growth rate of several populations of the bivalve Arctica islandica (Mollusca: Bivalvia) were estimated by using the growth lines laid down during their first ten years of life. Attention was focused on populations from the North Sea, but for comparison small samples from adjacent waters were also analysed. A four-fold difference in the average growth rate was found between the slowest and fastest growing shells.Principal component analysis was used to summarize the inter-relationships between environmental variables and growth rates. Shell growth correlated positively with primary production and temperature and inversely with depth and the silt content of the sediment. The North Sea specimens were found to have a strong positive correlation with grain size. Since sediment characteristics also depend on bottom currents, it is suggested that these increased rates reflect lateral seston flux as additional food supply.In a multiple regression model, applied to all available data, average annual temperature, primary production and the interaction between production and water depth explained 50% of the variance. The derived standard coefficients for temperature, primary production and the interaction between depth and primary production were 0.90, 0.47 and −0.92 respectively. The results of this study suggest that the temperature effects on in situ shell growth are easily overruled by other environmental factors.If a similar model was calculated with North Sea data only, 75% of the variance was explained by temperature, primary production and depth×primary production. The standard coefficient for primary production was 1.26. The role of temperature in explaining the observed growth differences is negligible since the standard coefficient is −0.098. The interaction term, depth×primary production had a standard coefficient of −0.95.

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