Living the Wild Life
Colin

Series 4: Mulkear River - Sea Lamprey

Colin is in Annacotty and he is about to witness one of the great natural events to happen in Ireland. Sea Lampreys are on their way from the Atlantic to build nests for the breeding season. Lampreys are amazing pre-historic animals who have an extraordinary sucker for a mouth and they use this to drag rocks around the riverbed until they are satisfied with their arrangement. But the lampreys have a problem. A man made problem. Annacotty Weir is preventing the sea lampreys from getting upriver to their traditional spawning territories. This means that a good proportion of our sea lamprey population is concentrated in one small area of the river. Colin has heard about a wonderful environmental project to remove this obstacle and restore and improve habitat for not only the sea lamprey but also the otter and salmon. He is meeting up with Ruairi O'Conchuir who manages the Mulkear LIFE project to learn more about the work that they plan to do over the next four years.

Mulkear LIFE: www.mulkearlife.com
Is a five year partnership based project working on the restoration of the Mulkear River catchment for Atlantic Salmon, Sea Lamprey and European Otter. The catchment is part of the Lower Shannon Special Area of Conservation. MulkearLIFE is one of the first and most important integrated catchment management projects in Ireland and is a flagship European Commission co-funded LIFE Nature project with Inland Fisheries Ireland as lead partner. The main project objective is to restore, through in-stream rehabilitation works, degraded habitats along stretches of the Mulkear River and its principal tributaries. While the main target species are Atlantic Salmon, Sea Lamprey and Otter, the project actions benefit a wide range of other fish species, invertebrates, birds and mammals by creating habitat complexity which leads to an overall increase in biodiversity.
Degradation and loss of instream habitat due to river drainage and other land practices has had a negative impact on target species. The drainage schemes prevent the river from recovering to a more natural state and alternative solutions (i.e., habitat rehabilitation techniques) are required to mimic natural conditions. MulkearLIFE's instream work is helping to reduce sediment and create habitat that increases macroinvertebrates and fish. The instream work breaks uniform habitat and restores habitat complexity. The work reduces sediment input that impact spawning beds for salmon and lamprey. This in turn greatly supports a range of bird species, benefiting from the increased food supply. The instream work is being undertaken by our project partners Limerick County Council (LCC) and the Office of Public Works (OPW) and a total of 36.8km of river channel will be completed.
To improve the population of Sea Lamprey in the catchment MulkearLIFE must modify obstacles to their annual upstream migration. This will open up most of the catchment for sea lamprey spawning and recruitment. Currently a number of old mill weirs prevent sea lamprey from fully utilizing the catchment. This work is monitored by tagging and radio-tracking sea lamprey to determine how sea lamprey approach and navigate obstacles, the habitat they use and the habitat they use for spawning. The locations of the radio-tagged lamprey are uploaded on www.mulkearlife.com so that local schools and the general public can view their movements and learn more about their life cycle.

The Mulkear catchment has a number of Invasive Weeds (Giant Hogweed, Japanese Knotweed, and Himalayan Balsam) which have a very negative impact on the riparian zone. The riparian zone is the interface between the land and the watercourse. It is important as a food source and for the provision of cover for young salmon. Native vegetation improves bank function by protecting banks from erosion during flood conditions while invasive weeds lead to river bank instability, erosion and siltation of gravel beds used by salmon for spawning. Large invasive plants, like those MulkearLIFE is attempting to control and eradicate, reduce biodiversity by out-shading native plants.

The Mulkear catchment has a good population of Otter but in some areas numbers are low. In these areas the project is improving the breeding and resting habitat for otter. Otter survey work is a critical element of this work and MulkearLIFE will be placing artificial otter holts in sites considered necessary.

MulkearLIFE is also working closely with the local farming community to address local water quality concerns and developing alternative solutions to cattle drinks for cattle with direct access to the river. This is to counteract trampling by livestock which may lead to siltation and organic pollution problems particularly in smaller streams. MulkearLIFE is working on 12 demonstration farms to trial alternative cattle drink solutions. Improvement in overall water quality and invertebrate diversity on these demonstration farms will be monitored.

Promoting biodiversity and environmental awareness is of crucial importance to MulkearLIFE. The project has a comprehensive Environmental Educational Programme in local schools and within the wider community to promote a heightened sense of "environmental ownership" and to highlight the importance of the river catchment as an important natural resource that needs to be protected and supported.

For further information: www.mulkearlife.ie

 

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