A significant portion of MulkearLIFE’s work programme is to control invasive plant species along the river corridor as they have detrimental impact on the projects target species. Dense populations of invasive plants alter the ecology of infested habitats by suppressing indigenous plant species which results in a significant reduction in floral and faunal diversity. These dense stands can suppress and exclude all other plants which play an important role in river bank stabilisation. When these invasive plants die back in winter the exposed soils can be washed into the river during floods. This destabilises the banks and the sediment washed into the rivers which can destroy the spawning gravels of resident fish populations. The loss of spawning habitat directly impacts sea lamprey and Atlantic salmon which in turn reduces the food supply for otter. The loss of native riparian plants and the destabilisation of the river banks also negatively impacts otter and reduces biodiversity.
Large stand on Giant Hogweed (Image: Glen Wightman)
Non-native invasive plant species are problematic throughout the Mulkear catchment. Limerick County Council, with support and guidance from MulkearLIFE, were able to treat substantial sections of river in their area of jurisdiction during the month of June 2013. Over 15 kms of river channel was treated by Limerick County Council using a boat mounted spraying system in the main channel of the Mulkear River and truck-mounted system on the smaller tributary rivers.
Treating an extensive stand of knotweed (Image: Glen Wightman)
MulkearLIFE’s other main project partner, the Office of Public Works has an ongoing treatment programme to control and manage Giant Hogweed and various knotweed species in their area of jurisdiction. The Office of Public Works completed treatment work on 16 kms of river channel in the Killeenagarriff, Newport and Annagh river catchments. All work was completed on foot using knapsack sprayers.
Monitoring of Giant Hogweed (Images: Glen Wightman)
All treatment work is undertaken using the herbicide Glyphosate (sold under a number of brand names Roundup®, Gallup®, etc.) as it the only chemical applicant with the necessary approval for use near water. Both the Office of Public Works and Limerick County Council’s spray crews are trained in the proper use of herbicides and comply with all health and safety considerations. Great care is given during spraying operations to minimise any harmful damage to non-target species and fauna. Monitoring work by MulkearLIFE staff has shown that treated areas have reduced densities of invasive plants and a reestablishment of native species.
Monitoring of Knotweed (Images: Glen Wightman)
Considerable work on invasive plant species was also undertaken by the Mulkear Conservation Volunteers (MCV). Significant work was undertaken at various High Nature Value (HNV) sites such as Annacotty where Himalayan balsam has been manually removed for the past three years.
MCV members manually remove Himalayan Balsam (Image: Ruairí Ó Conchúir)
MulkearLIFE also undertook considerable outreach work on invasives during 2013. MulkearLIFE was delighted to be in a position to host two large groups of Teagasc advisors and planners as part of a training workshop organised jointly by Teagasc and Inland Fisheries Ireland. The nature of invasive species in the catchment and in particular the problem of Giant Hogweed, Japanese Knotweed, Himalayan Balsam and Pheasant Berry was discussed in detail during site visits to farms with river frontage.
Teagasc staff review Pheasant Berry on the Bilboa River (Image: Ruairí Ó Conchúir)
Teagasc advisors review Himalayan Balsam (Image: Glen Wightman)
MulkearLIFE was delighted to have an opportunity to highlight and display the work of LCC, OPW and the MCV’s in controlling NNIS at two international conferences in 2013. The conferences provided invaluable networking opportunities as it was an ideal platform to meet and share ideas with like-minded professionals and practitioners involved with aquatic invasive species and the protection and restoration of Europe’s rivers. Conference goers were thrilled with Mulkear Life’s community engagement and local community involvement, such as the establishment of the conservation volunteers, which has been of critical importance and a key factor in the success of the project.
MulkearLIFE display at FIN’s Conference (Image: Glen Wightman)
To date over 200kms of channel has been treated; this includes multiple spraying over a number of years. MulkearLIFE looks forward to 2014 and our ongoing work to control and manage the NNI riparian plant species in the catchment. We look forward to working in partnership not only with our own Project Partners but also with the many groups and individuals who helped progress our work in 2014. We look forward to restoring many river banks into species rich riparian zones.