scholarly journals The concept of fecundity regulation in plaice (Pleuronectes platessa) tested on three Irish Sea spawning populations

2007 ◽  
Vol 64 (4) ◽  
pp. 587-601 ◽  
Author(s):  
J Kennedy ◽  
P R Witthames ◽  
R DM Nash
Keyword(s):  
Spatial Scales ◽  
Irish Sea ◽  
The West ◽  
Liverpool Bay ◽  
Pleuronectes Platessa ◽  
Isle Of Man ◽  
Spawning Areas ◽  
Temporal And Spatial ◽  
The Irish Sea ◽  
Different Levels

The fecundity of European plaice (Pleuronectes platessa) in the Irish Sea between 2000 and 2004 was estimated during the spawning season for fish in the three main spawning areas (Liverpool Bay, the Cumbrian coast, and the western Irish Sea) and one small spawning group on the west coast of the Isle of Man. Fecundity was also estimated during September of 2003 and 2004. The aim of this was to assess the variability in fecundity between areas and years in the Irish Sea and also to identify when differences in fecundity become apparent in the maturation cycle. There were variations in fecundity on both the temporal and spatial scales. The greatest variation in fecundity between years occurred in the western Irish Sea, whereas there was no variation between years in the southeastern Irish Sea (Liverpool Bay). There was no difference in fecundity between areas or years during September. The maximum fecundity in plaice is determined by the total weight of the fish at the end of follicle recruitment in the ovary, and differences in the fecundity of each population are the result of different levels of down-regulation in the period between the end of follicle proliferation and spawning.

Hydrographic Observations in the Eastern Irish Sea With Particular Reference to the Distribution of Nutrient Salts

1971 ◽  
Vol 51 (1) ◽  
pp. 159-182 ◽  
Author(s):  
P. G. W. Jones ◽  
A. R. Folkard
Keyword(s):  
Organic Phosphorus ◽  
Irish Sea ◽  
Liverpool Bay ◽  
Isle Of Man ◽  
Phosphate Nitrate ◽  
Distribution And Ecology ◽  
The Irish Sea ◽  
Physical And Chemical ◽  
Current Systems ◽  
Made In

INTRODUCTIONStudies on the physical hydrography of the Irish Sea, based mainly on temperature and salinity observations, have been made by Bowden (1955) and Lee (1960). The current systems in various parts of the Irish Sea have been investigated by Bowden & Sharaf El Din (1966), Harvey (1968), Ramster & Hill (1969) and Hill & Ramster (1971). Various smaller-scale physical observations made by other workers have been listed by the above authors.There are not as many references in the literature to the distribution of nutrient salts in the Irish Sea. Jones & Haq (1963) measured phosphate in Liverpool Bay as part of an investigation into the distribution of the alga Phaeocystis. Slinn & Offlow (1968) have made regular routine measurements of phosphate, nitrate and silicate over a number of years off Port Erin, Isle of Man. Ewins & Spencer (1967) measured phosphate, organic phosphorus, nitrate and silicate in the Menai Straits, and Liss (1969) surveyed the distribution of silicate in the western Irish Sea.During recent years the Fisheries Laboratory at Lowestoft has investigated the distribution and ecology of plankton and larval plaice in the Irish Sea, and a supporting programme of both physical and chemical hydrographic observations has been made in the area. Ramster & Hill (1969) and Hill & Ramster (1971) have summarized the results of the Lowestoft current measurements. The present paper describes an investigation into the distribution of temperature, salinity, phosphate, nitrate and silicate. The occurrence of Phaeocystis is also reported as an extension of the earlier work by Jones & Haq (1963).

scholarly journals The Occurrence and Breeding of Sagitta Elegans Verrill and Sagitta Setosa J. Müller in Parts of the Irish Sea

1941 ◽  
Vol 25 (1) ◽  
pp. 113-124 ◽  
Author(s):  
E. Lowe Pierce
Keyword(s):  
Irish Sea ◽  
Annual Number ◽  
Breeding Period ◽  
Spawning Period ◽  
Liverpool Bay ◽  
Isle Of Man ◽  
Three Stages ◽  
The Irish Sea ◽  
Reproductive Cycles ◽  
Breeding Seasons

An investigation has been made of the species of Sagitta present in parts of the Irish Sea, their relative occurrence, and the annual number of reproductive cycles of each species. Three stages of maturity as described by Russell (1932a) have been used. To determine the maturity the Sagitta were transferred to a solution of 75% alcohol and stained with borax carmine.S. elegans Verrill and S. setosa J. Müller were collected in Liverpool Bay and in Port Erin harbour, Isle of Man. The former species was predominant at Port Erin. The coasts of Liverpool Bay have been added to the permanent range of S. setosa.At Port Erin there appears to be but one chief spawning period for S. elegans which extends generally from January through May. Following May the young forms appear in numbers and gradually mature through December to repeat the annual cycle.There appear to be two main breeding seasons for S. setosa in the outer Mersey Channels. The first and most noticeable begins in April and extends into June. There is evidence for a second breeding period in August.Both species were found in the samples taken from Morecambe Bay and Anglesey. The stage of maturity of these agreed with the Sagitta caught at the same time at Port Erin and Liverpool.The total monthly catches of Sagitta from Port Erin and the outer Mersey Channels have been recorded.

The Little Manx Nation: Antiquarianism, Ethnic Identity, and Home Rule Politics in the Isle of Man, 1880–1918

2000 ◽  
Vol 39 (2) ◽  
pp. 217-240 ◽  
Author(s):  
John Belchem
Keyword(s):  
United Kingdom ◽  
General Meeting ◽  
Irish Sea ◽  
British Politics ◽  
Home Rule ◽  
Isle Of Man ◽  
The United Kingdom ◽  
Victorian Period ◽  
The Irish Sea ◽  
Frank Kermode

As imperial pride flourished in the racial discourse of late Victorian British politics, ethnic revival and Celtic nationalism also gained purchase and resonance. These complex and seemingly competing issues of identity extended beyond the “four nations” of the United Kingdom to the Isle of Man, a crown dependency constitutionally outside the United Kingdom but at the very center of the British Isles. In this “land of home rule,” adrift in the Irish Sea, the juxtaposition of Britishness and Celticism was particularly acute, compounded by the proud persistence of Norse traditions. Manx independence within the Atlantic archipelago was symbolized by the annual Tynwald Day ceremony, a Viking “Thing” or general meeting, at which the year's new legislation was promulgated in both English and Manx Gaelic. In the late Victorian period, as Anglo-Manx business syndicates invested heavily in the “visiting industry,” transforming the island into “one large playground for the operatives of Lancashire and Yorkshire,” gentlemanly antiquarians constructed (and/or invented) the necessary traditions to safeguard Manx cultural distinctiveness and its devolved political status. Through the assertion of Celticism, a project that tended to downgrade Norse contributions to the island's past, the little Manx nation girded itself against cultural anglicization, yet remained unquestionably loyal to the British empire.Slightly other than English, the Manx have displayed what Sir Frank Kermode has described as “mild alienation” and “qualified foreignness,” characteristics that need to be considered in the wider debate about British identity.

scholarly journals IV.—On the Drifts of the West and South Borders of the Lake District, and on the Three Great Granitic Dispersions

1871 ◽  
Vol 8 (85) ◽  
pp. 303-312 ◽  
Author(s):  
D. Mackintosh
Keyword(s):  
Small Area ◽  
Irish Sea ◽  
Lake District ◽  
The West ◽  
Boulder Clay ◽  
The Irish Sea ◽  
Sea Cliff

Boulder-scars.—From Maryport to Parkgate, the E. coast of the Irish Sea at intervals exhibits accumulations or concentrations of large boulders, which are locally called scars. They may be seen in all stages of formation, from the denudational area, where they are in course of being left by the washing away of the clayey matrix, to the depositional area, where they have become half-covered with recent sand and shingle. In many places (as between Seascale and near Silecroft) there are so many boulders within a small area as to show that a considerable thickness of the clay must have been removed. With the exception of having tumbled down as the cliffs were undermined and worn back by the sea, many of the boulders may still rest nearly in the positions they occupied in the clay, but (as is evidenced on the coast at Parkgate) others, up to a great diameter, may have been shifted horizontally. Some of the scars exist where the Boulder-clay would appear to have risen up into ridges or mounds, as no clay is now found opposite to them at the base of the sea-cliff. Others are clay and boulder plateaux, visibly connected with the cliff-line. Most of the scars, I believe, are remnants of the great Lower Brown Boulder-clay. The most conspicuous boulder in the scars S.W. of Bootle, is Eskdale-fell granite, accompanied by a little Criffell granite, and a great number of the usual felspathic erratics.

From midden to megalith? The Mesolithic-Neolithic transition in western Britain

2007 ◽  
Author(s):  
Vicki Cummings
Keyword(s):  
Transition Process ◽  
The Other ◽  
Irish Sea ◽  
Technological Transformation ◽  
Neolithic Transition ◽  
Isle Of Man ◽  
The Past ◽  
Hunting And Gathering ◽  
The Irish Sea

The transition from the Mesolithic to the Neolithic in Britain and Ireland remains one of the most debated and contested transitions of prehistory. Much more complex than a simple transition from hunting and gathering to farming, the Mesolithic–Neolithic transition in Britain has been discussed not only as an economic and technological transformation, but also as an ideological one. In western Britain in particular, with its wealth of Neolithic monuments, considerable emphasis has been placed on the role of monumentality in the transition process. Over the past decade the author‧s research has concentrated on the early Neolithic monumental traditions of western Britain, a deliberate focus on areas outside the more ‘luminous’ centres of Wessex, the Cotswold–Severn region, and Orkney. This chapter discusses the transition in western Britain, with an emphasis on the monuments of this region. In particular, it discusses the areas around the Irish Sea – west Wales, the Isle of Man, south-west and western Scotland – as well as referring to the sequence on the other side of the Irish Sea, specifically eastern Ireland.

Stylistic Influences in Early Manx Sculpture

2009 ◽  
Author(s):  
David M. Wilson
Keyword(s):  
Irish Sea ◽  
Isle Of Man ◽  
Stylistic Influences ◽  
The Irish Sea

This chapter examines the influences in the early sculpture in the Isle of Man, particularly the crosses that were previously described as Celtic. It suggests that the inscriptions in the Manx sculpture epigraphically and linguistically relate the island to the lands round the Irish Sea, while their typology and style history provide rough chronological yardsticks. The findings reveal that most pre-Viking memorial stones can be found in cemeteries on the sites of keeills.

scholarly journals On the Food of Young Plaice (Pleuronectes platessa)

1922 ◽  
Vol 12 (4) ◽  
pp. 678-687 ◽  
Author(s):  
Andrew Scott
Keyword(s):  
Present Report ◽  
Stomach Contents ◽  
Annual Reports ◽  
Irish Sea ◽  
Pleuronectes Platessa ◽  
Larval Stages ◽  
Marine Biological Association ◽  
Open Sea ◽  
Pelagic Eggs ◽  
The Irish Sea

The investigation of the food contents in the stomachs of young fishes was included in the scheme of scientific investigations drawn up and initiated by Professor Herdman for the Lancashire Sea Fisheries Committee nearly thirty years ago. The lengthy series of Annual Reports contain here and there accounts of the observations made on the stomach contents of various Pleuronectidæ captured close inshore, and the pelagic stages of other fishes caught from time to time in the plankton tow-nets. No systematic attempt has, however, been made, in connection with the investigation of the Irish Sea, to determine the food of any particular species of fish during the early part of its life history.Other observers working in other areas, notably Dr. Marie Lebour at Plymouth, have added very much to our knowledge of the early food of young fishes. Dr. Lebour's reports, published in the Journal of the Marine Biological Association, Vols. XI and XII, deal with a very large number of larval and post-larval stages of the more important food fishes caught in the tow-nets and young fish-trawl in Plymouth Sound and beyond.The present report gives an account of the food contained in the stomachs of young plaice (Pleuronectes platessa, Linn.) from a few days after hatching to about five months old. The samples examined in April and May were taken from the spawning pond at Port Erin, Isle of Man, where they had hatched from the pelagic eggs spawned by the adult plaice early in 1921. The later stages examined during May to August represented young plaice hatched in the open sea about the same time as those in the pond, and which had made their way close inshore.

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