scholarly journals Feeding of Atlantic salmon (Salmo salar L.) post-smolts in the Northeast Atlantic

2006 ◽  
Vol 63 (8) ◽  
pp. 1488-1500 ◽  
Author(s):  
Monika Haugland ◽  
Jens Christian Holst ◽  
Marianne Holm ◽  
Lars Petter Hansen
Keyword(s):  
Atlantic Salmon ◽  
Condition Factor ◽  
Pelagic Fish ◽  
Norwegian Sea ◽  
Northeast Atlantic ◽  
The North ◽  
Important Prey ◽  
The United Kingdom ◽  
Spawning Areas ◽  
High Condition

Abstract Stomach samples from 1384 Atlantic salmon, collected from 1991 to 2003 in the Northeast Atlantic, were analysed to fill the gap between studies on post-smolt diet in fjords and coastal areas of the Northeast Atlantic and studies on the diet of pre-adults and adults in the Norwegian Sea. The post-smolts fed largely on 0-group fish. Blue whiting was an important prey only in the slope current transporting the larvae from the spawning areas west of the United Kingdom into the North and Norwegian Seas. Sandeel and herring were important or present in the stomachs throughout most of the area studied. Unusually large quantities of 0-group herring in the Norwegian Sea in summer 2002 coincided with a high condition factor of post-smolts that year. The forage ratio of the post-smolts was positively related to the proportion of herring in the stomachs and the abundance of herring recruits. Despite these findings, the most productive period for Atlantic salmon on record, the 1970s, coincided with the collapse of the Norwegian spring-spawning herring, which raises the question as to whether herring is more important as a competitor than as a food source. Hyperiid amphipods were more important prey than krill, in contrast to the situation for other pelagic fish species.

scholarly journals Diets of herring, mackerel, and blue whiting in the Norwegian Sea in relation to Calanus finmarchicus distribution and temperature conditions

2006 ◽  
Vol 63 (1) ◽  
pp. 117-127 ◽  
Author(s):  
Irina Prokopchuk ◽  
Evgeniy Sentyabov
Keyword(s):  
Stomach Content ◽  
Diet Composition ◽  
Pelagic Fish ◽  
Calanus Finmarchicus ◽  
Norwegian Sea ◽  
Main Prey ◽  
Blue Whiting ◽  
Important Prey ◽  
Hydrographic Conditions ◽  
Feeding Area

Abstract Diets of Norwegian spring-spawning herring, mackerel, and blue whiting in the Norwegian Sea are investigated in relation to the distribution of plankton and hydrographic conditions. Fish stomachs and zooplankton samples were collected during summer (June and July) cruises in 2001 and 2002. Calanus finmarchicus was the principal prey of mackerel, accounting for 53–98% of total stomach content by weight. The diet composition of herring varied depending on feeding area and availability of food under various environmental conditions. C. finmarchicus was important prey for herring only in July 2001 (about 77% by weight) in the central part of the sea and in June 2002 (about 82% by weight) near the Lofotens. In July 2002 appendicularians (Oikopleura spp.), amphipods (mainly Parathemisto abissorum), and euphausiids were important in the diet of herring, and at some stations cannibalism was observed. The main prey of blue whiting were amphipods (10–34% by weight), appendicularians (11–34%), and euphausiids (8–47%), as they usually feed deep in the water column, though C. finmarchicus was important, particularly in June 2002, when blue whiting were caught in the upper layers of the sea. Higher water temperatures indirectly affect pelagic fish through accelerated development of their prey and favourable conditions for migration farther north.

scholarly journals Feeding interactions between Atlantic salmon (Salmo salar Linnaeus) post-smolts and other planktivorous fish in the Northeast Atlantic

2020 ◽  
Author(s):  
Kjell Rong Utne ◽  
Katie Thomas ◽  
Jan Arge Jacobsen ◽  
Johanna Fall ◽  
Niall Pádraig Ó Maoiléidigh ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Interspecific Competition ◽  
Salmo Salar ◽  
Fish Larvae ◽  
Pelagic Fish ◽  
Diet Overlap ◽  
Growth And Survival ◽  
Pelagic Species ◽  
Northeast Atlantic ◽  
Feeding Interactions

In recent decades, there has been a decline in the marine growth of Atlantic salmon over large parts of the distribution range. One hypothesis for this reduced growth is increased interspecific competition with other planktivorous pelagic fish in the ocean. Here, interactions between salmon post-smolts and other pelagic fish (mackerel and herring) in the Northeast Atlantic were investigated. There was a low diet overlap between post-smolts and the two other planktivorous pelagic species. Both mackerel and herring were feeding predominantly on copepods and other small zooplankton while salmon were feeding mostly on fish larvae. All three species feed on euphausiids and amphipods. Furthermore, post-smolts geographically overlapped with mackerel but had a low geographic overlap with herring. There was no correlation between the abundance or survival of salmon from key index rivers and the abundance of pelagic fish. This study did not find evidence to support the hypothesis that observed temporal changes in marine growth and survival of salmon can be explained by feeding interactions with pelagic fish.

scholarly journals Phenological and phenotypic changes in Atlantic salmon populations in response to a changing climate

2012 ◽  
Vol 69 (9) ◽  
pp. 1686-1698 ◽  
Author(s):  
Christopher D. Todd ◽  
Kevin D. Friedland ◽  
Julian C. MacLean ◽  
Bryce D. Whyte ◽  
Ian C. Russell ◽  
...  
Keyword(s):  
Atlantic Salmon ◽  
Age Structure ◽  
Condition Factor ◽  
Temporal Trends ◽  
Maternal Influence ◽  
Phenotypic Changes ◽  
Changing Climate ◽  
The North ◽  
Age Related ◽  
Run Timing

Abstract Todd, C. D., Friedland, K. D., MacLean, J. C., Whyte, B. D., Russell, I. C., Lonergan, M. E., and Morrissey, M. B. 2012. Phenological and phenotypic changes in Atlantic salmon populations in response to a changing climate. – ICES Journal of Marine Science, 69: 1686–1698. Atlantic salmon (Salmo salar) of southern European origin migrating to the Norwegian Sea currently encounter anomalously high sea-surface temperatures, and returning adults are of low mean condition factor. For the River North Esk (Scotland), time-series changes in river age-structure of emigrant smolts and returning one- and two-sea-winter (1SW and 2SW) adults are assessed. A comparison of the river age-structure of returning adults (1977–1999) with that of their respective annual emigrant smolt cohorts shows no evidence of river age-related bias in survivorship at sea. Evidence is presented of a possible transgenerational, or maternal, influence (poor somatic condition of spawners) driving reduced quality of emigrant S2 smolts in the North Esk. This effect is concurrent with an influence of freshwater climate as indicated by the North Atlantic Oscillation Index (NAOI). The maternal influence and NAOI variation in the winter immediately prior to smolt migration jointly explain approximately 29 (S2) and 17% (S3), respectively, of the variation in the mean size of smolts over the period 1975–2010. Run-timing of 1SW adult cohorts returning to Scotland shows recent delays. Variation in river flow did influence mean return date for the River Tweed, but adult condition factor, which itself shows temporal trends likely to be associated with ocean climate change, was the primary significant explanatory variable for run-timing in the rivers North Esk and Tweed. Overall, in years of poorer adult condition, 1SW salmon stay at sea longer.

scholarly journals Relationships between North Atlantic salmon, plankton, and hydroclimatic change in the Northeast Atlantic

2012 ◽  
Vol 69 (9) ◽  
pp. 1549-1562 ◽  
Author(s):  
Grégory Beaugrand ◽  
Philip C. Reid
Keyword(s):  
Time Series ◽  
Atlantic Salmon ◽  
North Atlantic ◽  
Trophic Levels ◽  
Marked Rise ◽  
Sea Temperature ◽  
Northeast Atlantic ◽  
Monotonic Trend ◽  
The North ◽  
Hydroclimatic Change

Abstract Beaugrand, G. and Reid, P. C. 2012. Relationships between North Atlantic salmon, plankton, and hydroclimatic change in the Northeast Atlantic – ICES Journal of Marine Science, 69: 1549–1562. The abundance of wild salmon (Salmo salar) in the North Atlantic has declined markedly since the late 1980s as a result of increased marine mortality that coincided with a marked rise in sea temperature in oceanic foraging areas. There is substantial evidence to show that temperature governs the growth, survival, and maturation of salmon during their marine migrations through either direct or indirect effects. In an earlier study (2003), long-term changes in three trophic levels (salmon, zooplankton, and phytoplankton) were shown to be correlated significantly with sea surface temperature (SST) and northern hemisphere temperature (NHT). A sequence of trophic changes ending with a stepwise decline in the total nominal catch of North Atlantic salmon (regime shift in ∼1986/1987) was superimposed on a trend to a warmer dynamic regime. Here, the earlier study is updated with catch and abundance data to 2010, confirming earlier results and detecting a new abrupt shift in ∼1996/1997. Although correlations between changes in salmon, plankton, and temperature are reinforced, the significance of the correlations is reduced because the temporal autocorrelation of time-series substantially increased due to a monotonic trend in the time-series, probably related to global warming. This effect may complicate future detection of effects of climate change on natural systems.

The identity of Sertularia reptans Linnaeus, 1758 (Bryozoa, Candidae)

Zootaxa ◽  
2012 ◽  
Vol 3563 (1) ◽  
pp. 26 ◽  
Author(s):  
LEANDRO M. VIEIRA ◽  
MARY E. SPENCER JONES
Keyword(s):  
United Kingdom ◽  
North Sea ◽  
Morphological Characteristics ◽  
Limited Distribution ◽  
Northeast Atlantic ◽  
Linnean Society ◽  
The North ◽  
The United Kingdom ◽  
The North Sea ◽  
Herbarium Sheet

This paper includes a reassessment of Scrupocellaria reptans (Linnaeus, 1758) (basionym Sertularia reptans), thelectotype of which is selected and figured from among herbarium-sheet specimens held at the Linnean Society of London.Material previously assigned to S. reptans was examined, providing morphological characteristics to distinguishScrupocellaria ellisi n. sp. Scrupocellaria reptans has a geographically limited distribution in the United Kingdom, while S. ellisi is more widespread in the North Sea, Northeast Atlantic, Adriatic and Tasmania.

Present Status of the Salmonids Atlantic Salmon and Sea-Trout in the Dutch Part of the River Rhine

1994 ◽  
Vol 29 (3) ◽  
pp. 37-41 ◽  
Author(s):  
W. G. Cazemier
Keyword(s):  
Atlantic Salmon ◽  
Salmo Trutta ◽  
Natural Populations ◽  
River Rhine ◽  
Sea Trout ◽  
The Past ◽  
The North ◽  
Trout Population ◽  
The North Sea ◽  
Heavy Pollution

In the past, the anadromous salmonids, Atlantic salmon (Salmo salar) and sea-trout (Salmo trutta), have formed natural populations in the river Rhine. From the beginning of the nineteenth century onwards, the greater part of the drainage area of the river has been gradually altered from a more or less rural and agricultural area, into a highly industrialised one with subsequent industrialisation, river-engineering and heavy pollution. These developments are considered to be the major cause for the disappearance of the populations of anadromous salmonid fish in the 1950s. The water quality has recovered significantly during the past 25 years. From about 1975 onwards, this process gave rise to a recovery of the anadromous trout population. Results of recent studies of the sea-trout migration pattern are presented. They reveal that nowadays these salmonids can complete their up- and downstream migrations from the North Sea to places, situated at hundreds of kilometres upward the river and vica versa. The numbers of recorded Atlantic salmon and catch locations in inland waters are presented. They show a significant increase since 1989. These phenomena can be understood as promising signs of the recovery of the Rhine aquatic ecosystem.

Becoming a Community Musician

2018 ◽  
Author(s):  
Dave Camlin ◽  
Katherine Zesersen
Keyword(s):  
United Kingdom ◽  
Community Music ◽  
Knowledge And Attitudes ◽  
The North ◽  
The United Kingdom ◽  
Democratic Pedagogy ◽  
Situated Perspective

In this chapter, we outline an approach to training in community music that is congruent with its pluralistic and diverse character. From the situated perspective of Sage Gateshead, a large music organization in the north of the United Kingdom, we reflect on some of the ways that musicians have developed the skills, knowledge, and attitudes to become effective practitioners of community music. Rooted in a dialogic and democratic pedagogy, the training processes described herein recognize the highly individualized nature of community music practices, and are underpinned by the explicitly humanistic values and attitudes that unite them.

scholarly journals Physiological resilience of pink salmon to naturally occurring ocean acidification

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Andrea Y Frommel ◽  
Justin Carless ◽  
Brian P V Hunt ◽  
Colin J Brauner
Keyword(s):  
British Columbia ◽  
Elevated Co2 ◽  
Condition Factor ◽  
Pacific Salmon ◽  
Pink Salmon ◽  
Hypoxia Tolerance ◽  
High Co2 ◽  
The North ◽  
Naturally Occurring ◽  
Co2 Levels

Abstract Pacific salmon stocks are in decline with climate change named as a contributing factor. The North Pacific coast of British Columbia is characterized by strong temporal and spatial heterogeneity in ocean conditions with upwelling events elevating CO2 levels up to 10-fold those of pre-industrial global averages. Early life stages of pink salmon have been shown to be affected by these CO2 levels, and juveniles naturally migrate through regions of high CO2 during the energetically costly phase of smoltification. To investigate the physiological response of out-migrating wild juvenile pink salmon to these naturally occurring elevated CO2 levels, we captured fish in Georgia Strait, British Columbia and transported them to a marine lab (Hakai Institute, Quadra Island) where fish were exposed to one of three CO2 levels (850, 1500 and 2000 μatm CO2) for 2 weeks. At ½, 1 and 2 weeks of exposure, we measured their weight and length to calculate condition factor (Fulton’s K), as well as haematocrit and plasma [Cl−]. At each of these times, two additional stressors were imposed (hypoxia and temperature) to provide further insight into their physiological condition. Juvenile pink salmon were largely robust to elevated CO2 concentrations up to 2000 μatm CO2, with no mortality or change in condition factor over the 2-week exposure duration. After 1 week of exposure, temperature and hypoxia tolerance were significantly reduced in high CO2, an effect that did not persist to 2 weeks of exposure. Haematocrit was increased by 20% after 2 weeks in the CO2 treatments relative to the initial measurements, while plasma [Cl−] was not significantly different. Taken together, these data indicate that juvenile pink salmon are quite resilient to naturally occurring high CO2 levels during their ocean outmigration.

scholarly journals FRI0649-HPR HYDROXYCHLOROQUINE PRESCRIBING AND OPHTHALMOLOGY SCREENING WITHIN RHEUMATOLOGY DEPARTMENTS IN THE NORTH-WEST OF THE UNITED KINGDOM: A PROSPECTIVE REGIONAL AUDIT

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 928.2-929
Author(s):  
S. Juman ◽  
T. David ◽  
L. Gray ◽  
R. Hamad ◽  
S. Horton ◽  
...  
Keyword(s):  
High Risk ◽  
Risk Group ◽  
Service Level ◽  
High Risk Group ◽  
North West ◽  
The North ◽  
The United Kingdom ◽  
The Uk ◽  
Treatment Dosage ◽  
Sd Oct

Background:Hydroxychloroquine (HCQ) is widely used in the management of rheumatoid arthritis and connective tissue disease. The prevalence of retinopathy in patients taking long-term HCQ is approximately 7.5%, increasing to 20-50% after 20 years of therapy. Hydroxychloroquine prescribed at ≤5 mg/kg poses a toxicity risk of <1% up to five years and <2% up to ten years, but increases sharply to almost 20% after 20 years. Risk factors for retinopathy include doses >5mg/kg/day, concomitant tamoxifen or chloroquine use and renal impairment. The UK Royal College of Ophthalmologists (RCOphth) 2018 guidelines for HCQ screening recommend optimal treatment dosage and timing for both baseline and follow-up ophthalmology review for patients on HCQ, with the aim of preventing iatrogenic visual loss. This is similar to recommendations made by the American Academy of Ophthalmology (2016).Objectives:To determine adherence to the RCOphth guidelines for HCQ screening within the Rheumatology departments in the North-West of the UK.Methods:Data for patients established on HCQ and those initiated on HCQ therapy were collected over a 7 week period from 9 Rheumatology departments.Results:473 patients were included of which 56 (12%) were new starters and 417 (88%) were already established on HCQ. 79% of the patients were female, with median ages of 60.5 and 57 years for new and established patients respectively. The median (IQR) weight for new starters was 71 (27.9) kg and for established patients, 74 (24.7) kg.20% of new starters exceeded 5mg/kg daily HCQ dose. 16% were identified as high risk (9% had previously taken chloroquine, 5% had an eGFR <60ml/min/m2and 2% had retinal co-pathology). Of the high-risk group, 44% were taking <5mg/kg. In total, 36% of new starters were referred for a formal baseline Ophthalmology review.In the established patients, 74% were taking ≤5mg/kg/day HCQ dose and 16% were categorized as high risk (10% had an eGFR less than 60ml/min/m2, 3% had previous chloroquine or tamoxifen use and 2% had retinal co-pathology). In the high-risk group, 75% were not referred for spectral domain optical coherence tomography (SD-OCT). 41% of patients established on HCQ for <5 years, and 33% of patients on HCQ for >5 years were not referred for SD-OCT. Reasons for not referring included; awaiting 5 year review, previous screening already performed and optician review advised.Since the introduction of the RCOphth guidelines, 29% patients already established on HCQ had an alteration in the dosage of HCQ in accordance with the guidelines. In the high-risk group, 16% were not on the recommended HCQ dose.Conclusion:This audit demonstrates inconsistencies in adherence to the RCOphth guidelines for HCQ prescribing and ophthalmology screening within Rheumatology departments in the North-West of the UK for both new starters and established patients. Plans to improve this include wider dissemination of the guidelines to Rheumatology departments and strict service level agreements with ophthalmology teams to help optimize HCQ prescribing and screening for retinopathy.Acknowledgments:Drs. S Jones, E MacPhie, A Madan, L Coates & Prof L Teh. Co-1st author, T David.Disclosure of Interests:None declared

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