Estimating the age of juvenile loggerhead sea turtles in the North Atlantic

1997 ◽  
Vol 75 (1) ◽  
pp. 40-46 ◽  
Author(s):  
G. C. Hays ◽  
R. Marsh

Analysis of previously published records shows that the modal size of juvenile loggerhead sea turtles (Caretta caretta) found around the United Kingdom (the area north of 49°N and east of 12°W) is a carapace length of 20.5 cm. These turtles are believed to originate from nesting beaches in North America (principally Florida). We estimated their trans-Atlantic drift time using data from satellite-tracked buoys and from a mathematical model and, hence, estimated that the modal age of these juvenile turtles was between 1.80 and 3.75 years.

2015 ◽  
Vol 282 (1804) ◽  
pp. 20143129 ◽  
Author(s):  
Kara L. Dodge ◽  
Benjamin Galuardi ◽  
Molly E. Lutcavage

Leatherback sea turtles ( Dermochelys coriacea ) travel thousands of kilometres between temperate feeding and tropical breeding/over-wintering grounds, with adult turtles able to pinpoint specific nesting beaches after multi-year absences. Their extensive migrations often occur in oceanic habitat where limited known sensory information is available to aid in orientation. Here, we examined the migratory orientation of adult male, adult female and subadult leatherbacks during their open-ocean movements within the North Atlantic subtropical gyre by analysing satellite-derived tracks from fifteen individuals over a 2-year period. To determine the turtles' true headings, we corrected the reconstructed tracks for current drift and found negligible differences between current-corrected and observed tracks within the gyre. Individual leatherback headings were remarkably consistent throughout the subtropical gyre, with turtles significantly oriented to the south-southeast. Adult leatherbacks of both sexes maintained similar mean headings and showed greater orientation precision overall. The consistent headings maintained by adult and subadult leatherbacks within the gyre suggest use of a common compass sense.


2017 ◽  
Vol 121 (1-2) ◽  
pp. 222-229 ◽  
Author(s):  
Christopher K. Pham ◽  
Yasmina Rodríguez ◽  
Axelle Dauphin ◽  
Rita Carriço ◽  
João P.G.L. Frias ◽  
...  

1951 ◽  
Vol 5 (4) ◽  
pp. 825-832

With the development of certain administrative frictions (concerning coal quotas, occupation costs, and the scrap metal treaty) between the western occupying powers and the German Federal Republic, early indications were that if the talk of “contractual agreements” did materialize it would reserve, for the occupying powers, wide controls over important areas of west Germany's internal and external affairs. In Washington, however, a general modification of approach was noted during the September discussions between the United States Secretary of State (Acheson), the United Kingdom Foreign Secretary (Morrison), and the French Foreign Minister (Schuman), preparatory to the Ottawa meetings of the North Atlantic Council.


2008 ◽  
Vol 5 (5) ◽  
pp. 1199-1213 ◽  
Author(s):  
A. Landolfi ◽  
A. Oschlies ◽  
R. Sanders

Abstract. To enable an accurate estimate of total excess nitrogen (N) in the North Atlantic, a new tracer TNxs is defined, which includes the contribution of organic nutrients to the assessment of N:P stoichiometric anomalies. We measured the spatial distribution of TNxs within the subtropical North Atlantic using data from a trans-Atlantic section across 24.5° N occupied in 2004. We then employ three different approaches to infer rates of total excess nitrogen accumulation using pCFC-12 derived ventilation ages (a TNxs vertical integration, a one end-member and a two-end member mixing model). Despite some variability among the different methods the dissolved organic nutrient fraction always contributes to about half of the TNxs accumulation, which is in the order of 9.38±4.18×1011 mol N y−1. We suggest that neglecting organic nutrients in stoichiometric balances of the marine N and P inventories can lead to systematic errors when estimating deviations of nitrogen excess or deficit relative to the Redfield ratio in the oceans. For the North Atlantic the inclusion of the organic fraction to the excess nitrogen pool leads to an upward revision of the N supply by N2 fixation to 10.2±6.9×1011 mol N y−1.


2021 ◽  
Vol 115 (4) ◽  
pp. 715-721

In July, the United States, the North Atlantic Treaty Organization (NATO), the European Union (EU), and other allies attributed a variety of malicious cyber activities, including the Microsoft Exchange hack, to China. This joint attribution builds on commitments made in June summits with NATO, the G7, the EU, and the United Kingdom, and is consistent with the Biden administration's multilateral approach to confronting cybersecurity threats and China more generally. Still, critics question whether the administration's efforts will succeed in altering the behavior of states that pose cybersecurity threats to the United States.


1950 ◽  
Vol 4 (2) ◽  
pp. 362-369

The Governments of the United States of America and the United Kingdom of Great Britain and Northern Ireland;Being parties to the North Atlantic Treaty signed at Washington on April 4, 1949;Considering their reciprocal pledges under Article 3 of the North Atlantic Treaty separately and jointly with the other parties, by means of continuous and effective self-help and mutual aid, to maintain and develop their individual and collective capacity to resist armed attack;


Author(s):  
Thorkild Kjærgaard

Thorkild Kjærgaard: The Peace in Kiel, Greenland, and the North Atlantic, 1814–2014 At the peace conference in Kiel (North Germany) in January 1814, the Danish-Norwegian North Atlantic Empire that controlled an enormous area of land and water, including not only Denmark (with Schleswig-Holstein) and Norway but also Iceland, the Faroe Islands and the huge, thinly populated ice-covered island of Greenland, was dissolved by the victorious powers of the Napoleonic wars. Norway was given to Sweden as compensation for Finland, which Sweden — now in the victorious coalition — had lost to Russia in 1809. Rather surprisingly, the Kingdom of Denmark — now, without Norway, Europe’s smallest independent country — was entrusted with Greenland, Iceland and the Faroe Islands, although these three North Atlantic areas since early medieval times had been a part of the Kingdom of Norway. Without question, this was a major historical injustice. For Denmark, the outcome of the 1814 conference in Kiel was twofold: it was reduced to a very small country and it became — and still is — a polar nation, which it had not been before. The article discusses three aspects of this complex. Firstly: What happened in Kiel? Why were the three North Atlantic territories taken from Norway and given to Denmark? Was it, as it has been claimed by a majority of historians, the merit of sly Danish diplomats or was it — as the author believes — the will of the United Kingdom that was imposed on two small countries, Sweden and Denmark? Secondly, it is discussed how Denmark dealt with its new role as a polar nation. It turns out that Denmark initially was a rather hesitant, not to say, unwilling polar nation. Gradually, however, the extraordinary qualities of the North Atlantic islands, especially Greenland, were recognized. Since the end of the 19th century, Greenland has been a major subject of Danish art and literature, just as it has been a decisive dimension of Danish scientific research. The last section of the article deals with the significance of Greenland for Danish security and foreign policy. It is shown how the suffocating dependency on Great Britain after 1814 gradually was reduced thanks to a rapprochement to the new world power, the United States, which very early on showed interest in Greenland, which is, geographically, a part of the North American continent. The close alliance with the United States has saved Greenland for Denmark, just as it has been extremely helpful for Denmark in number of critical situations since 1814, but it also has its price. The price is that Denmark always follows US and never questions US actions. Relatively, Denmark, one of President Bush’s “willing nations,” has had more casualties on the American battlefields in Iraq and Afghanistan than any other of the United States’ allied nations. The Danish soldiers who have been killed on Middle East or Central Asiatic battlefields since 2001 have died for Greenland.


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