scholarly journals First record of the rare crab Asthenognathus atlanticus Monod, 1933 (Crustacea: Brachyura: Varunidae) in the North Sea

2021 ◽  
Vol 50 (3) ◽  
pp. 352-358
Author(s):  
Marco Faasse ◽  
Hendrik Gheerardyn ◽  
Rob Witbaard ◽  
Joël Cuperus
Keyword(s):  
North Sea ◽  
First Record ◽  
Western Mediterranean ◽  
Distribution Range ◽  
Marine Waters ◽  
The West ◽  
The North ◽  
The North Sea ◽  
Northward Expansion ◽  
First Time

Abstract Several species new to the area were collected while monitoring Dutch marine waters using a dredge. The varunid crab Asthenognathus atlanticus Monod, 1933 was recorded for the first time in the North Sea. Until 2008, this relatively rare crab was known from the west coast of Africa and the western Mediterranean to northern Brittany in the north. In recent years, its distribution range has expanded, as indicated by records from the Bay of the Seine and the area around Dieppe-Le Tréport. Our finding from Brown Bank (southern North Sea) indicates a further, northward expansion of its distribution range. We list the hosts with which the crab is associated. Earlier arguments for climate change as an explanation for the northward range expansion are supported.

First Record of the American Jack Knife Clam Ensis Directus on the French Coast of the North Sea

1993 ◽  
Vol 73 (1) ◽  
pp. 233-235 ◽  
Author(s):  
C. Luczak ◽  
J.-M. Dewarumez ◽  
K. Essink
Keyword(s):  
North Sea ◽  
Coastal Waters ◽  
New Records ◽  
First Record ◽  
English Channel ◽  
Southern Bight ◽  
The North ◽  
German Coast ◽  
The North Sea ◽  
First Time

Ensis directus (Bivalvia: Solenidae) was noted for the first time along the French coast of the North Sea in June 1991. High numbers of post larvae after a period of northerly winds indicate that settled larvae originated from adult populations in Belgian or Dutch coastal waters. Future dispersal of Ensis directus could be used as a biological tracer of coastal water movements between the Southern Bight of the North Sea and the English Channel.The American jack knife clam, Ensis directus (Conrad, 1843), synonym Ensis americanus (Binney, 1870)sensu van Urk (1964,1972), was discovered in Europe in the German Bight for the first time in June 1979 (Von Cosel et al., 1982). This species is assumed to have been transported in its larval stage by a ship containing ballast water. Considering the dimensions of the specimens, this probably happened in the first half of 1978 (Von Cosel et al., 1982; Mühlenhardt-Siegel et al., 1983). Since then this species has spread rapidly in the North Sea in subtidal and intertidal areas. Dense populations were found along the German coast within a few years (Von Cosel et al., 1982; Mühlenhardt-Siegel et al., 1983; Swennen et al., 1985). In 1986 Ensis directus was reported from the north and east Danish coasts as far as the Belgian coast (Kerkhof & Dumoulin, 1987) (Figure 1). Since then no new records have been reported.

Offshore Claims and Problems in the North Sea

1965 ◽  
Vol 59 (3) ◽  
pp. 505-522 ◽  
Author(s):  
Richard Young
Keyword(s):  
North Sea ◽  
Large Scale ◽  
Geneva Convention ◽  
Legal Principles ◽  
The North ◽  
Legal Problems ◽  
The North Sea ◽  
The Subject ◽  
First Time ◽  
Economic Considerations

The possible presence of very large petroleum and natural gas reserves in the area beneath the North Sea is currently the subject of intense investigation. If confirmed, as seems likely in at least some localities, this occurrence will raise legal problems of considerable interest and complexity. For the North Sea is not merely an oilfield covered by water: for centuries it has been one of the world's major fishery regions and the avenue to and from the world's busiest seaports. Thus all three of the present principal uses of the sea—fishing, navigation, and the exploitation of submarine resources—promise to meet for the first time on a large scale in an area where all are of major importance. The process of reconciling the various interests at stake will provide the first thoroughgoing test of the adequacy and acceptability of the general principles laid down in the 1958 Geneva Convention on the Continental Shelf and should add greatly to the practice and precedents available in this developing branch of the law. In the present article an attempt is made to review some of the geographical and economic considerations involved in the North Sea situation, to note some of the technical and legal developments that have already taken place, and to consider these elements in the light of the various interests and legal principles concerned.

scholarly journals First record of brown colouration of Atlantic cod (Gadus morhua, L.) from the North Sea

Oceanologia ◽  
2014 ◽  
Vol 56 (1) ◽  
pp. 159-163
Author(s):  
Agnieszka Rybczyk ◽  
Przemysław Czerniejewski ◽  
Joanna Rokicka-Praxmajer
Keyword(s):  
North Sea ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
First Record ◽  
The North ◽  
The North Sea

scholarly journals A brachiopod-dominated sea-floor assemblage from the Late Pliocene of the eastern Netherlands

2013 ◽  
Vol 92 (2-3) ◽  
pp. 171-176 ◽  
Author(s):  
F.P. Wesselingh ◽  
W.J.M. Peters ◽  
D.K. Munsterman
Keyword(s):  
North Sea ◽  
Marine Waters ◽  
Late Pliocene ◽  
Sea Floor ◽  
The North ◽  
Storm Wave ◽  
Southeastern Margin ◽  
The North Sea ◽  
Early Late ◽  
Commensal Relationship

AbstractA sea-floor assemblage from hardened sandstone boulders in which lingulid brachiopods predominate is recorded from the Oosterhout Formation near Balgoy (province of Gelderland, the Netherlands). Dinoflagellate cysts indicate a late Early-Late Pliocene (late Zanclean-Piacenzian) age of these boulders; the entire assemblage is indicative of clear marine waters near storm wave base along the southeastern margin of the North Sea Basin at the time. A possible commensal relationship between the lingulid brachiopods and the gastropod Calyptraea chinensis is implied.

scholarly journals Lactuca tatarica (Asteraceae) in embryonic dunes on Wolin Island (NW Poland)

2015 ◽  
Vol 39 (1) ◽  
pp. 61-66 ◽  
Author(s):  
Wojciech Kowalski W. A. ◽  
Andrzej Łysko ◽  
Agnieszka Popiela
Keyword(s):  
Baltic Sea ◽  
19Th Century ◽  
North Sea ◽  
Natural Habitat ◽  
The North ◽  
The North Sea ◽  
The 19Th Century ◽  
First Time ◽  
Nw Poland

Abstract By the end of the 19th century, Lactuca tatarica was reported for the first time from an adventive occurrence on the North Sea and Baltic Sea coasts. In Wolin Island, the species has become established in the natural habitat and is clearly spreading in recent years. The community with L. tatarica was studied currently on the western point of Wolin Island along the stretch between the mouth of the Świna (Swine) River and a newly constructed breakwater of the external harbour. The taxon occupies relatively low parts of the sandy elevations of dune ridges, in patches of the Honckenyo-Agropyretum juncei association (habitat 2110). Furthermore, L. tatarica has been reported in recent years from some locations in Świnoujście (Usedom (Uznam) Island), Międzyzdroje, Wisełka and Międzywodzie.

scholarly journals Why do jellyfish bloom in Norwegian waters and what can be done to recover the ecosystems in the North Sea and on the Norwegian coast?

2017 ◽  
Author(s):  
Johannes Hamre
Keyword(s):  
North Sea ◽  
West Coast ◽  
Trophic Levels ◽  
The West ◽  
Fish Stocks ◽  
Norwegian Coast ◽  
The North ◽  
Key Species ◽  
Wide Range ◽  
The North Sea

The ecosystems with their relationships between fish species and stocks, have been established by evolution for millions of years, but during the last 50 years, the ecosystems in the North Sea and along the Norwegian coast have been changed fundamentally by fisheries. The North Sea mackerel stock has been depleted and its feeding grounds have been invaded by the Western mackerel which spawns west of Ireland. This stock is now very rich in numbers and occupies the North Sea, the Norwegian Sea and the western Barents Sea. If the trend continues, mackerel may outcompete many of the other fish stocks in the area. Traditionally and until the beginning of the 1970s, there was a large stock of sandeel spawning in the North Sea and on the Norwegian coast. Sandeel juveniles was an important food source for a wide range of species, including sea mammals and birds. The fact that this stock has also been overfished, may explain many changes observed in the ecosystem on the west coast of Norway, for example a large reduction in the populations of sea birds. There are several instances where ecosystems shift to sustain jellyfish blooms in response to depletion of forage fish stocks. This was registered in Namibia in the 1990’s, where the pilchard stock was decimated and the biomass of jellyfish soon became overwhelming. On the west-coast of Norway, there are now frequent blooms of jellyfish, yet another indication that a controlling factor is missing in the system, in this case sandeel, which is a key species in the transfer of nutrients from zooplankton to higher trophic levels in the area. In this paper, I give a description of the situation and some suggested measures that should be taken in fisheries management.

Continuous Trawl Protection of Heating Cable for Direct Electric Heating of Flowlines

2005 ◽  
Author(s):  
Ha˚var Ilstad ◽  
Svein Harald Sa˚tendal ◽  
Bjo̸rn Melve ◽  
Atle Harald Bo̸rnes ◽  
Lars Henning ◽  
...  
Keyword(s):  
North Sea ◽  
Electric Heating ◽  
Full Length ◽  
Electrical Heating ◽  
Reservoir Temperature ◽  
The North ◽  
Heating Cable ◽  
Analytical Work ◽  
The North Sea ◽  
First Time

The following paper describes the experimental and analytical work that was carried out in the development of a continuous external trawling protection for the Direct Electrical Heating cables for the subsea flowlines on the Kristin Field in the North Sea. The developed trawl protection was able to absorb the required 5.0 kJ energy without damage to the cable. The Kristin field is the most extreme HP/HT subsea field developed in Norway to date (170 degC reservoir temperature and 911 barg pressure). This is the first time that a continuous trawl protection is applied to the full length of a flowline. The normal approach would be burying to avoid interaction with fishing activities, however since this is a HP/HT subsea flowline it was necessary with an extra cooling from unburied pipelines to reduce the riser temperatures.

scholarly journals Recent Foraminifera from the North Sea (Forties and Ekofisk areas) and the continental shelf west of Scotland

1985 ◽  
Vol 4 (2) ◽  
pp. 117-125 ◽  
Author(s):  
John W. Murray
Keyword(s):  
Continental Shelf ◽  
North Sea ◽  
Standing Crop ◽  
High Energy ◽  
The West ◽  
The North ◽  
Energy Environment ◽  
Bottom Waters ◽  
The North Sea ◽  
Northern North Sea

Abstract. The regions studied are all of mid continental shelf depth (70–145 m) and have bottom waters of normal marine salinity. The North Sea has lower bottom water temperatures than those to the west of Scotland. However, the major difference between the two regions is one of tidal and/or wave energy: the northern North Sea is a low energy environment of muddy sand deposition whereas the sampled part of the continental shelf west and north of Scotland is a moderate to high energy environment of medium to coarse biogenic carbonate sedimentation.The physical differences between the two main areas are reflected in the living and dead foraminiferal assemblages. The northern North Sea is a region of free-living species whereas the continental shelf west of Scotland has immobile and mobile attached species living on firm substrates. The northern North Sea is very fertile and has high standing crop values.The dead assemblages are small in size and very abundant. To the west of Scotland the sea is less fertile, standing crop values are low, the dead assemblages are moderate to large in size and reasonably abundant due to the slow rate of dilution by sediment.

scholarly journals Report on the Surface Collections made by Mr. W. T. Grenfell in the North Sea and West of Scotland

1890 ◽  
Vol 1 (4) ◽  
pp. 376-381 ◽  
Author(s):  
Gilbert C. Bourne
Keyword(s):  
Sulphuric Acid ◽  
North Sea ◽  
Deep Sea ◽  
Early Spring ◽  
The Other ◽  
The West ◽  
The North ◽  
The North Sea

Mr. Wilfrid Grenfell, the Superintendent of the Mission to Deep Sea Fishermen, has most kindly arranged to carry on a series of observations on the pelagic fauna and the fishes of the seas traversed by the Mission boats in the course of their work. The following report gives an account of the pelagic fauna collected in the North Sea during the early spring, and in the west of Scotland and Kinsale Harbour during the summer. The collections were preserved in picro-sulphuric acid and spirit, and were forwarded to Plymouth for examination. Owing to pressure of work, and to my leaving Plymouth somewhat unexpectedly, I have not been able to make a thorough investigation of all the collections, but have worked out the Copepoda with care, and have confined myself to short notes on the other species.

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