Sustainability & Environment
For generations to come
Eel traps & transport
About the eel
The European eel (Anguilla Anguilla) has been an important indigenous fish in Europe since the beginning of time.
Eels spawn in the Saragosa Sea, with their larvae travelling across the Atlantic ocean on the prevailing currents, to reach the coasts of Europe in November/December as roughly 20 mm long transparent eels (referred to as 'glass' eels).
From there they begin to pigment and move into fresh water in early spring, at which stage they are called 'elvers'.
Eels spend from 10 to 20 years in freshwater before sexually maturing. They then start to move down through the river systems, to begin their long journey back across the Atlantic to spawn.
Decline in eel stocks
Since the mid-1980s, there has been a notable decline in the number of elvers returning to Europe, with a subsequent decline in eel stocks throughout European rivers.
Why the decline?
Explanations have varied from:
- Climate change
- Pollution
- Effect of man-made barriers and weirs such as dams and hydro stations
While no one reason prevails, it is likely that all these issues are contributing factors.
ESB's eel conservation role
ESB Fisheries Conservation have employed full time staff in silver eel fishing at Killaloe since the beginning of the Shannon Hydro Scheme, and from the mid 1960s at Athlone and Cloonlara.
Elvers were captured at Parteen weir, Ardnacrusha, the River Maigue and the River Feale, and restocked into the lakes above Killaloe.
Managing & monitoring eel stocks
In 1992, ESB Fisheries Conservation began the Shannon Eel Management Programme, and initiated an eel survey to investigate the possibility of job creation from eel fishing.
In 1998, NUIG produced a report of their survey work since 1992, stating that due to a shortage of available elvers, it was not feasible to sustain full time employment at a commercial eel fishery on the River Shannon.
Since then, eel stocks have been monitored closely on the rivers Shannon, Erne and Lee, but no increase in the biomass of eels has been detected.
Trap & transport
In 2000, we began a programme of 'trap and transport' of Silver Eel from Killaloe to sites below Parteen Weir, to aid the numbers of eels returning to sea.
From 2000 to 2004, a target of 10% of the total Shannon catch was released. Since 2005 the total catch at Killaloe was released.
EU eel stock recovery plan
In 2007, a new EU regulation* was introduced to provide for the recovery of European eel stocks, requiring each EU member to submit National Eel Stock Recovery Plans.
* EU Council Regulation 1100/2007
The EU eel recovery plan is built around the principle that management of the river systems in each country should permit at least 40% of the biomass of spawner escapement that migrated to sea during former, pristine conditions, to do so in the future.
National Report for Ireland
In December 2008, the Department of Communications, Energy and Natural Resourses, following consultation with all the relevant stakeholders, submitted the 'National Report for Ireland on Eel Stock Recovery Plan' to the EU for consideration. It was approved by the EU Commission.
The plan outlines the proposed trap and transport figures for the ESB-controlled areas of the River Shannon and River Erne:
- 22 tonnes per year up to 2012 for the River Shannon
- 22 tonnes on the Erne in 2009, rising to 34 tonnes in 2010 and 39 tonnes in 2011
Meeting our targets
From September 2009, ESB Fisheries have engaged:
- 3 contracted fishing crews at Killaloe on the River Shannon
- 2 contracted fishing crews at Roscor Bridge on the River Erne
The crews will operate throughout the silver eel season (September to March) on all nights with favourable eel fishing conditions.
These stations will also be sites for ongoing scientific research into eel trapping methods and prediction of silver eel movement through the river systems.
All silver eels captured will be transported from the fishing sites to release locations below the dams on each river system, using specialised ESB-owned eel transporting tanks and equipment.
This will ensure that eels collected from the contracted crews are released in healthy state to continue their journey across the Atlantic.