Growth of the edible crab (Cancer pagurusL.) off south-west England

1974 ◽  
Vol 54 (4) ◽  
pp. 803-823 ◽  
Author(s):  
D. B. Bennett
Keyword(s):  
Egg Production ◽  
Carapace Width ◽  
Large Male ◽  
Annual Growth ◽  
Published Data ◽  
North East ◽  
South West ◽  
Males And Females ◽  
Moulting Cycle ◽  
South West England

Moult increments, annual moult frequency and hence annual growth were determined from suture-tagged edible crabs (Cancer pagurusL.) released and recaptured off Devon, Cornwall, and Dorset.The average moult increments of males and females at a premoult carapace width of 100 mm were similar; at larger sizes the average moult increment of females was considerably less than that of males. Annual moult frequency ofC. pagurusin south-west England decreased with increase in size, females more so than males.As a result of the smaller moult increments and lower moult frequency of females, their annual growth is considerably less than that of males. This appears to be the result of three aspects of sex and reproduction: (1) reduction in moult increments, probably as a result of competition for nutritive resources between egg production and body growth; (2) the interruption of the moulting cycle by successive annual spawnings from a single impregnation at the previous moult; and (3) accentuation of the larger increments in weight at moulting of male crabs due to the allometric growth of their chelae. A consequence of the higher growth rate of males is the presence of very large male crabs – a distinctive feature of the population structure of the stock off south-west England.The growth of C.pagurusin south-west England was compared with published data for stocks off the east and north-east coast. Moult increments were similar for both areas, but there were considerable differences in the moult frequencies. In the south-west, males moult more frequently than females; the opposite is the case for the east and north-east crab stocks. A valid reason for this difference has not yet been established.

Further results from a tagging study of pelagic sharks in the north-east Atlantic

1990 ◽  
Vol 70 (4) ◽  
pp. 707-720 ◽  
Author(s):  
J. D. Stevens
Keyword(s):  
Northern Spain ◽  
East Atlantic ◽  
North West ◽  
North East ◽  
The North ◽  
Isurus Oxyrinchus ◽  
South West ◽  
Predicted Values ◽  
Galeorhinus Galeus ◽  
South West England

A further 69 recaptures are reported from a tagging study of pelagic sharks initiated in 1970 in the north-east Atlantic. Galeorhinus galeus tagged in England were recaptured in the eastern Atlantic from southern Spain to north-west of Iceland. Among the 42 G. galeus recaptured the longest time at liberty was about 12 years and the greatest distance travelled was 2461 km. Among the 21 Prionace glauca recaptured the l ongest time at liberty was 10.7 years, and seven sharks moved distances between 4362 and 7176 km. One shark tagged in south-west England was recaptured in the South Atlantic off South America. An Isurus oxyrinchus was at liberty for 4–6 years and a Lamna nasus for up to about 13 years. Lamna nasus were recaptured from northern Norway to northern Spain. The growth rates of the tagged sharks were close to the predicted values for G. galeus, were slower for P. glauca and faster for L. nasus.

First results of shark tagging in the north-east Atlantic, 1972–1975

1976 ◽  
Vol 56 (4) ◽  
pp. 929-937 ◽  
Author(s):  
J. D. Stevens
Keyword(s):  
Adolescent Females ◽  
East Atlantic ◽  
Sport Fishery ◽  
North East ◽  
The North ◽  
Isurus Oxyrinchus ◽  
South West ◽  
First Results ◽  
South West England ◽  
Alopias Vulpinus

Since the early 1950s a sport fishery for sharks has existed off south-west England. On average some 5000 sharks are taken annually on rod and line between May and October. The catch consists almost entirely of blue sharks, the majority of which are immature or adolescent females, limited numbers of the porbeagle, Lamna nasus Bonnaterre, mako, Isurus oxyrinchus Rafinesque and very occasionally the thresher, Alopias vulpinus Bonnaterre.

TBE in United Kingdom

2020 ◽  
Keyword(s):  
United Kingdom ◽  
Clinical Disease ◽  
England And Wales ◽  
Probable Case ◽  
The United Kingdom ◽  
South West ◽  
Louping Ill ◽  
The Uk ◽  
North And South ◽  
South West England

Until 2019, TBE was considered only to be an imported disease to the United Kingdom. In that year, evidence became available that the TBEV is likely circulating in the country1,2 and a first “probable case” of TBE originating in the UK was reported.3 In addition to TBEV, louping ill virus (LIV), a member of the TBEV-serocomplex, is also endemic in parts of the UK. Reports of clinical disease caused by LIV in livestock are mainly from Scotland, parts of North and South West England and Wales.4

The Metamorphosed Limestones and Associated Contaminated Igneous Rocks of the Carlingford District, Co. Louth

1932 ◽  
Vol 69 (5) ◽  
pp. 209-233 ◽  
Author(s):  
G. D. Osborne
Keyword(s):  
Igneous Rocks ◽  
The South ◽  
Ordnance Survey ◽  
Igneous Complex ◽  
North East ◽  
The North ◽  
South West ◽  
Carboniferous Limestone ◽  
Contamination Effects

THE Carlingford-Barnave district falls within the boundaries of Sheet 71 of the Ordnance Survey of Ireland, and forms part of a broad promontory lying between Carlingford Lough on the north-east and Dundalk Bay on the south-west. The greater part of this promontory is made up of an igneous complex of Tertiary age which has invaded the Silurian slates and quartzites and the Carboniferous Limestone Series. This complex has not yet been investigated in detail, but for the purposes of the present paper certain references to it are necessary, and these are made below. The prevalence of hybrid-relations and contamination-effects between the basic and acid igneous rocks of the region is a very marked feature, and because of this it has been difficult at times to decide which types have been responsible for the various stages of the metamorphism.

scholarly journals Diocesan Licensing and Medical Practitioners in South-West England, 1660–1780

2004 ◽  
Vol 48 (1) ◽  
pp. 49-68 ◽  
Author(s):  
Ian Mortimer
Keyword(s):  
Early Modern ◽  
Specific Context ◽  
Medical Practitioners ◽  
Medical Expertise ◽  
North West ◽  
The North ◽  
Decentralized Trade ◽  
South West ◽  
The Many ◽  
South West England

The licensing of provincial surgeons and physicians in the post-Restoration period has proved an awkward subject for medical historians. It has divided writers between those who regard the possession of a local licence as a mark of professionalism or proficiency, those who see the existence of diocesan licences as a mark of an essentially unregulated and decentralized trade, and those who discount the distinction of licensing in assessing medical expertise availability in a given region. Such a diversity of interpretations has meant that the very descriptors by which practitioners were known to their contemporaries (and are referred to by historians) have become fragmented and difficult to use without a specific context. As David Harley has pointed out in his study of licensed physicians in the north-west of England, “historians often define eighteenth-century physicians as men with medical degrees, thus ignoring … the many licensed physicians throughout the country”. One could similarly draw attention to the inadequacy of the word “surgeon” to cover licensed and unlicensed practitioners, barber-surgeons, Company members in towns, self-taught practitioners using surgical manuals, and procedural specialists whose work came under the umbrella of surgery, such as bonesetters, midwives and phlebotomists. Although such fragmentation of meaning reflects a diversity of practices carried on under the same occupational descriptors in early modern England, the result is an imprecise historical literature in which the importance of licensing, and especially local licensing, is either ignored as a delimiter or viewed as an inaccurate gauge of medical proficiency.

Triassic tragedy—a bone bed in the Otter Sandstone of East Devon, south‐west England

Geology Today ◽  
2021 ◽  
Vol 37 (5) ◽  
pp. 176-183
Author(s):  
Robert A. Coram ◽  
Jonathan D. Radley ◽  
Michael J. Benton
Keyword(s):  
South West ◽  
South West England

scholarly journals Fishery-induced changes in Norwegian red king crab (Paralithodes camtschaticus) reproductive potential

2013 ◽  
Vol 71 (2) ◽  
pp. 365-373 ◽  
Author(s):  
Ann Merete Hjelset
Keyword(s):  
Egg Production ◽  
Barents Sea ◽  
Reproductive Potential ◽  
Size Composition ◽  
Red King Crab ◽  
Paralithodes Camtschaticus ◽  
King Crab ◽  
Males And Females ◽  
Induced Changes ◽  
Individual Fecundity

Abstract Hjelset, A. M. 2014. Fishery-induced changes in Norwegian red king crab (Paralithodes camtschaticus) reproductive potential. – ICES Journal of Marine Science, 71: 365–373. The introduced red king crab (Paralithodes camtschaticus) in the Barents Sea supports a valuable fishery in northern Norway. In this paper, I examine the effect of the increased harvest rate and the recently added female quota on the potential egg production of the stock. The size ranges of males and females in the period 1995–2011 were recorded, and estimated stock abundance of ovigerous females and established individual fecundity parameters from 2000–2007 were used to assess the reproductive potential of the stock from 1995–2011. The upper size ranges of males and females decreased throughout the period studied, presumably mainly due to fishing. The change in size composition among ovigerous females and functional mature males, and the reduced mean individual fecundity in the stock seem to have had a negative effect on the potential egg production of the stock.

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