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You searched for +publisher:"National University of Ireland – Galway" +contributor:("McCarthy, Thomas K"). Showing records 1 – 2 of 2 total matches.

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National University of Ireland – Galway

1. Egan, Fintan. Studies on the biology of juvenile European eels (Anguilla anguilla L.) in Irish rivers .

Degree: 2011, National University of Ireland – Galway

Over the past three decades recruitment of European eel (Anguilla anguilla L.) to inland waters has declined by more than 95%. The causes of this decline are still unclear although a number of factors are thought to have a contributory effect including pollution, habitat loss, climatic changes in the ocean, overfishing and the spread of non-indigenous parasites and disease. In this study, undertaken from 2008 to 2010, the abundance, timing and seasonal duration of eel recruitment was investigated on the Shannon, Erne and Lee river systems, where the natural connectivity of these rivers is interrupted by hydroelectric dams and regulating weirs. Catches of juvenile eels at fixed traps downstream of these structures were monitored and the length, weight and age of eels sampled were analysed. Total catch varied between years at each site and were generally low. The timing of the migration showed considerable interannual variability as well as differences between sites. Mean eel length was greater for eels trapped further upstream from the tidal limit of estuaries. At the Parteen regulating weir on the River Shannon variation in the juvenile eel catch was analysed in relation to environmental factors using multiple regression appropriate to time series data. Factors included in the regression model which explained a statistically significant portion of the variation in juvenile eel catch were: day length, flow, water temperature, moon fullness and year. An exceptional peak in the eel catch was recorded in August 2008 following very heavy rainfall. The catch recorded during August 2008 accounted for 51% of the total catch for the period 2008 to 2010. Juvenile eels sampled at fixed traps were examined for the presence of Anguillicoloides crassus, an introduced Asian parasitic nematode of eels that can affect swimbladder function. Investigations on the infection levels in yellow and silver eels are frequently reported but there is a paucity of information regarding infection of juvenile eels. Prevalence and intensity of infection was determined. Relationships between host length and condition and the infection intensity were also investigated. Juvenile eels sampled from the River Lee (N = 73) were found to be uninfected. Prevalence recorded for a sample from the Erne (N = 44) was 14% and mean intensity of infection was 1.0. On the River Shannon, samples (N = 498) were collected at the Ardnacrusha dam and Parteen regulating weir during 2008, 2009 and 2010. At Ardnacrusha elvers were more frequent in the trap catch and mean prevalence ranged from 23-66% with mean intensity ranging from 1.35 to 1.94. At Parteen, where larger juvenile eels are predominant in the trap catch, mean prevalence ranged from 59-66% and mean intensity ranged from 1.90 to 2.00. There was no significant correlation between the number of Anguillicoloides present and the condition factor of the eels sampled. Anguillicoloides infection of migrating juvenile eels used for stocking represents a mechanism of dispersal for the parasite to… Advisors/Committee Members: McCarthy, Thomas K (advisor).

Subjects/Keywords: Anguilla; Anguillicola crassus; Conservation; Environmental Factors; Fish Passage; Hydroelectric Dams; Juvenile Eel; Migration; Management; Recruitment; Traps

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Egan, F. (2011). Studies on the biology of juvenile European eels (Anguilla anguilla L.) in Irish rivers . (Thesis). National University of Ireland – Galway. Retrieved from http://hdl.handle.net/10379/3703

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Egan, Fintan. “Studies on the biology of juvenile European eels (Anguilla anguilla L.) in Irish rivers .” 2011. Thesis, National University of Ireland – Galway. Accessed December 05, 2020. http://hdl.handle.net/10379/3703.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Egan, Fintan. “Studies on the biology of juvenile European eels (Anguilla anguilla L.) in Irish rivers .” 2011. Web. 05 Dec 2020.

Vancouver:

Egan F. Studies on the biology of juvenile European eels (Anguilla anguilla L.) in Irish rivers . [Internet] [Thesis]. National University of Ireland – Galway; 2011. [cited 2020 Dec 05]. Available from: http://hdl.handle.net/10379/3703.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Egan F. Studies on the biology of juvenile European eels (Anguilla anguilla L.) in Irish rivers . [Thesis]. National University of Ireland – Galway; 2011. Available from: http://hdl.handle.net/10379/3703

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. MacNamara, Ruairi. Conservation biology of the European eel (Anguilla anguilla) on a hydropower-regulated Irish river .

Degree: 2012, National University of Ireland – Galway

The European eel (Anguilla anguilla) has a complex lifecycle, involving catadromous migration between marine spawning grounds and continental growth habitat. European eel stocks have undergone a serious population collapse, and recently introduced E.U. legislation (EC 1100/2007) specifies major conservation actions. In particular, the protection of potential spawners (i.e. silver eels) from continental waters is considered essential for stock recovery. Various aspects of silver eel migratory behaviour, population biology and conservation were examined on the hydropower-regulated River Shannon. The primary study site was at Killaloe eel fishing weir, where long-term reliable catch records are available. Ardnacrusha hydropower dam is located 18 km further downstream (near the tidal limit). Since 2000, silver eels captured at Killaloe are released below the hydropower dam as part of a 'trap and transport' conservation strategy. In 2009, Ireland's Eel Management Plan (EMP) specified that 30% of the silver eel production on River Shannon must be captured and released annually. As a result, four additional fishing sites were established in the mid/upper catchment. An estimated 228 013 silver eels, including a high proportion of females (75.9%), have been released to the lower River Shannon (2000-2010), thus avoiding the hazards associated with passage via Ardnacrusha. Analysis of silver eel migration dynamics/population structure on the river has demonstrated how multi-site capture has enabled EMP targets to be achieved (30.2% in 2009, 39.6% in 2010 and 41.9% in 2011), in addition to increasing the quantity of large female eels released. Silver eel trap and transport is ideally an interim conservation measure, pending development of non-intrusive alternatives (e.g. guidance technology, controlled spillage). To ensure effective implementation of these alternatives, accurate prediction of silver eel migration is essential. Therefore, two predictive approaches were evaluated on the lower River Shannon, by reference to silver eel catches at Killaloe: (i) the Migromat® biomonitor, which predicts migration based on the activity levels of captive eels, signalled 19.9-28.9% of the total catch, or 21.4-32.1% of migration events, during the evaluation period; (ii) alternatively, retrospective analysis of catch and environmental data (water temperature, discharge and lunar luminosity) were used to develop logistic regression models for prediction of silver eel migration. The predictive capacity of this approach varied, depending on the year (27.5-86.4% of the total catch, or 66.7-95.0% of migration events), but was generally more effective than the Migromat®. The use of behavioural guidance as a potential hydropower mitigation measure was also evaluated on the lower River Shannon. During an experiment involving an overwater light barrier at Killaloe eel weir, catch patterns were found to be significantly different between lights on and lights off periods. Eel response to the light barrier was size related, reflecting the… Advisors/Committee Members: McCarthy, Thomas K (advisor).

Subjects/Keywords: Silver eel; Anguilla anguilla; Downstream migration; Hydropower; Zoology; Natural Sciences

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

MacNamara, R. (2012). Conservation biology of the European eel (Anguilla anguilla) on a hydropower-regulated Irish river . (Thesis). National University of Ireland – Galway. Retrieved from http://hdl.handle.net/10379/3108

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

MacNamara, Ruairi. “Conservation biology of the European eel (Anguilla anguilla) on a hydropower-regulated Irish river .” 2012. Thesis, National University of Ireland – Galway. Accessed December 05, 2020. http://hdl.handle.net/10379/3108.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

MacNamara, Ruairi. “Conservation biology of the European eel (Anguilla anguilla) on a hydropower-regulated Irish river .” 2012. Web. 05 Dec 2020.

Vancouver:

MacNamara R. Conservation biology of the European eel (Anguilla anguilla) on a hydropower-regulated Irish river . [Internet] [Thesis]. National University of Ireland – Galway; 2012. [cited 2020 Dec 05]. Available from: http://hdl.handle.net/10379/3108.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

MacNamara R. Conservation biology of the European eel (Anguilla anguilla) on a hydropower-regulated Irish river . [Thesis]. National University of Ireland – Galway; 2012. Available from: http://hdl.handle.net/10379/3108

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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