Solar Driven Geomagnetic Anomalies and Sperm Whale (Physeter macrocephalus) Strandings Around the North Sea: An Analysis of Long Term Datasets

In spite of a continuously expanding physeteroid fossil record, our understanding of the origin and early radiation of the two modern sperm whale families Kogiidae Gill, 1871 (including the pygmy and dwarf sperm whales, Kogia spp.) and Physeteridae Gray, 1821 (including the great sperm whale, Physeter Linnaeus, 1758) remains limited, especially due to the poorly resolved phylogenetic relationships of a number of extinct species. Among those, based on fragmentary cranial material from the late early to middle Miocene of Antwerp (Belgium, North Sea basin), the small-sized Thalassocetus antwerpiensis Abel, 1905 has been recognized for some time as the earliest branching kogiid. The discovery of a new diminutive physeteroid cranium from the late Miocene (Tortonian) of Antwerp leads to the description and comparison of a close relative of T. antwerpiensis. Thanks to the relatively young ontogenetic stage of this new specimen, the highly modified plate-like bones making the floor of its supracranial basin could be individually removed, a fact that greatly helped deciphering their identity and geometry. Close morphological similarities with T. antwerpiensis allow for the reassessment of several facial structures in the latter; the most important reinterpretation is the one of a crest-like structure, previously identified as a sagittal facial crest, typical for kogiids, and here revised as the left posterolateral wall of the supracranial basin, comprised of the left nasal (lost in kogiids for which the postnarial region is known) and the left maxilla. Implemented in a phylogenetic analysis, the new anatomical interpretations result in the new Belgian specimen and T. antwerpiensis being recovered as sister-groups in the family Physeteridae. Consequently, the geologically oldest kogiids are now dated from the Tortonian, further extending the ghost lineage separating these early late Miocene kogiid records from the estimated latest Oligocene to earliest Miocene divergence of kogiids and physeterids.

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The ‘Yellow Danger’? Global forces and global fears in the North Sea and beyond (1600–1950)

International Journal of Maritime History ◽

10.1177/0843871415610502 ◽

2015 ◽

Vol 27 (4) ◽

pp. 743-754

Author(s):

Matthias van Rossum

Keyword(s):

Labour Market ◽

North Sea ◽

Labour Markets ◽

Labour Relations ◽

The North ◽

15Th Century ◽

Global Connections ◽

The North Sea

Since direct shipping routes between Europe and Asia opened up at the end of the 15th century, the growing intercontinental and regional shipping connections resulted in increasing entanglements between European and Asian maritime labour markets. This article analyses the long term development of the connections between European and Asian maritime labour markets and its impact on socio-cultural (and labour) relations through three elements: first, the changing connections between European and Asian maritime labour markets; second, the changing nature of European and Asian maritime labour markets and its influence on the positions of sailors; and third, the changing relations between European and Asian sailors and its effects on the reactions and interactions in a globalising maritime labour market. It explores how these changing global connections shaped encounters between European and Asian sailors on (intercontinental) shipping in and from the North Sea region, and how it affected the positions and reactions of its workers.

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Relevance of active faulting and seismicity studies to assessments of long-term earthquake activity and maximum magnitude in intraplate northwest Europe, between the Lower Rhine Embayment and the North Sea

Continental Intraplate Earthquakes: Science, Hazard, and Policy Issues ◽

10.1130/2007.2425(14) ◽

2007 ◽

Cited By ~ 23

Author(s):

Thierry Camelbeeck ◽

Kris Vanneste ◽

Pierre Alexandre ◽

Koen Verbeeck ◽

Toon Petermans ◽

...

Keyword(s):

North Sea ◽

Earthquake Activity ◽

Maximum Magnitude ◽

Active Faulting ◽

The North ◽

Northwest Europe ◽

The North Sea ◽

Lower Rhine Embayment ◽

Lower Rhine

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The history and future of the North Sea benthos

Proceedings of the Royal Society of Edinburgh Section B Biological Sciences ◽

10.1017/s0269727000002864 ◽

1978 ◽

Vol 76 (1-3) ◽

pp. 193-200

Author(s):

P. E. P. Norton

Keyword(s):

North Sea ◽

Bottom Type ◽

The North ◽

Late Tertiary ◽

Long Term Changes ◽

History Of ◽

The North Sea ◽

Temperature Depth

SynopsisThis is a brief review intended to supply bases for prediction of future changes in the North Sea Benthos. It surveys long-term changes which are affecting the benthos. Any prediction must take into account change in temperature, depth, bottom type, tidal patterns, current patterns and zoogeography of the sea and the history of these is briefly touched on from late Tertiary times up to the present. From a prediction of changes in the benthos, certain information concerning the pelagic and planktonic biota could also be derived.

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Warm-water decapods and the trophic amplification of climate in the North Sea

Biology Letters ◽

10.1098/rsbl.2010.0394 ◽

2010 ◽

Vol 6 (6) ◽

pp. 773-776 ◽

Cited By ~ 15

Author(s):

J. A. Lindley ◽

G. Beaugrand ◽

C. Luczak ◽

J.-M. Dewarumez ◽

R. R. Kirby

Keyword(s):

North Sea ◽

Warm Water ◽

Climate Signal ◽

Southern North Sea ◽

The North ◽

Ecosystem Shift ◽

The North Sea ◽

Induced Changes ◽

Water Species

A long-term time series of plankton and benthic records in the North Sea indicates an increase in decapods and a decline in their prey species that include bivalves and flatfish recruits. Here, we show that in the southern North Sea the proportion of decapods to bivalves doubled following a temperature-driven, abrupt ecosystem shift during the 1980s. Analysis of decapod larvae in the plankton reveals a greater presence and spatial extent of warm-water species where the increase in decapods is greatest. These changes paralleled the arrival of new species such as the warm-water swimming crab Polybius henslowii now found in the southern North Sea. We suggest that climate-induced changes among North Sea decapods have played an important role in the trophic amplification of a climate signal and in the development of the new North Sea dynamic regime.

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Comparing conceptual frameworks for a fish community MSY (FCMSY) using management strategy evaluation—an example from the North Sea

ICES Journal of Marine Science ◽

10.1093/icesjms/fsz015 ◽

2019 ◽

Vol 76 (4) ◽

pp. 813-823 ◽

Cited By ~ 3

Author(s):

Robert B Thorpe ◽

José A A De Oliveira

Keyword(s):

North Sea ◽

Management Strategy ◽

Fish Community ◽

Parameter Uncertainties ◽

Management Strategy Evaluation ◽

The North ◽

Strategy Evaluation ◽

The North Sea ◽

Definition Of

Abstract Maximum sustainable yield (MSY) is a well-established concept that is mandated by legislation, and has a clear theoretical meaning in terms of a single stock. However, its definition is problematic in a multispecies setting, which makes it more difficult to apply the MSY principle. In this study of the North Sea fish community, we consider several possible MSY candidates, and evaluate them in terms of their ability to produce optimum long-term yield whilst avoiding unacceptable risk of stock impairment. We perform this evaluation with an ensemble of size-structured models using a management strategy evaluation approach, in which harvest control rules (HCRs) are used to determine levels of fishing as a function of the proposed MSY target and stock status, taking account of recruitment and model parameter uncertainties. We find that HCRs of the type considered here are always useful in the scenarios we tested, as they reduce overfishing risk much more than average long-term yield. This is independent of the precise form of the HCR, so it is more important to implement one rigorously than obsess over the rule details. For a lax definition of overfishing, which accepts relatively severe stock depletion (B < 10% B0), and using HCRs, risks are “low” across all strategies, and the Nash equilibrium is the best performing MSY approach considered here. For more stringent definitions of “at risk” (e.g. likelihood of B < 20% of B0), the application of HCRs can allow a range of alternative formulations of MSY. Thus, the definition of MSY may be sensitive to judgements about acceptable levels of risk, and consistent application of a sensible management framework may be more important than developing the best possible theoretical definition of MSY.

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