Fine Gael TD for Galway West & Mayo South

Funding for Continued Removal of Invasive Plant Species from Lough Corrib

Lough Corrib at Rinnerroon before waterweed removal works
Lough Corrib near Rinnerroon before waterweed removal works

As Minister with responsibility for the Inland Fisheries sector I have allocated funding of €300,000 for 2019 to ensure Inland Fisheries Ireland’s (IFI) successful operations involving extensive removal of the invasive waterweed, Lagarosiphon Major (L.major), at Lough Corrib, Co. Galway, continue.  I have also asked IFI and his Department to continue liaison with the National Parks and Wildlife Service (NPWS), who have responsibility for the legislation covering Alien Invasive Species (AIS), and in particular liaison as regards species impacting on fisheries.

The management of the curly-leaved waterweed took place on Lough Corrib from January – July 2018 with a view to protecting this important angling resource and I am committing significant funding to IFI for 2019 for this initiative. I also welcome the new IFI research project commenced recently which will see scientists survey the distribution of the plant on the Lough. I want to encourage liaison between IFI and NPWS and other bodies on the issue of aquatic AIS so that a multi-agency approach can be brought to bear on the challenges involved” he added.

Lough Corrib near Rinnerroon after waterweed removal works
Lough Corrib near Rinnerroon after waterweed removal works

As part of the battle against L.major, Inland Fisheries Ireland cut and removed the weed across 73.5 hectares (73,500m2) of the Lough over a five month period in four sites which contained dense strands. These sites included Barrusheen Bay, Corrib View Bay, Drumsnauv Bay and Farnaught Bay.

In addition, 21.3ha (21, 320m2) of L.major was covered using the light excluding jute treatment method between May and July. The areas targeted included Cornamona Bay, School House Bay, Farnaught, Corrib View Bay, Bob’s Island, The Needles and Ballynalty Bay.  Finally, an area of 250m2 was eradicated using the hand picking method across Farnaught, Cornamona Bay, Corrib View Bay, Bob’s Island and The Needles.

The ongoing weed management operations carried out by Inland Fisheries Ireland has prevented the choking of bays by the weed which has occurred in the past. The management operations of L.major in Lough Corrib are supported annually by Galway Country Council and the Office of Public Works.

In addition to the management operations, Inland Fisheries Ireland commenced a research project last month which aims to establish the current distribution of L.major in Lough Corrib. New innovative methods are being trialled to survey the aquatic plant as part of this research. These include unmanned aerial drones, sub-aquatic remotely operated vehicles (ROV’s) and modern remote sensing techniques.

Physical and environmental factors will also be reviewed at sites on the lake each month to determine the influence of habitat and other factors on the distribution of the plant. The findings of the project will help inform policy on future control operations of the invasive plant in the future.


About Inland Fisheries Ireland


Inland Fisheries Ireland is a statutory body operating under the aegis of the Department of Communications, Climate Action and Environment (DCCAE) and was established under the Fisheries Act on 1st July 2010. Its principal function is the protection and conservation of the inland fisheries resource. Inland Fisheries Ireland promotes supports, facilitates and advises the Minister on the conservation, protection, management, development and improvement of inland fisheries, including sea angling. Inland Fisheries Ireland also develops policy and national strategies relating to inland fisheries and sea angling and advises the Minister on same.

About Lagarosiphon major

  • Lagarosiphon major is a submerged canopy-forming weed occurring in lakes, ponds and slow-moving watercourses.
  • It has curly leaves which are arranged spirally along the stem, which is hollow and fragile.
  • L.major is native to southern Africa and was introduced to Ireland by the horticulture industry as an oxygenating plant for use in artificial watercourses.
  • The plant is currently present in garden ponds, aquatic features on golf course and in artificial lakes at many locations throughout the country.
  • It was first recorded in a natural aquatic habitat in Ireland in 2005 when its presence was confirmed in a large sheltered bay on upper Lough Corrib.