An Asian clam found in Lough Derg
A leading scientist on invasive species has warned that Tipperary rivers and lakes are facing a threat from non-native species.
Dr Dan Minchin of the Lough Derg Science Group, warned at a meeting of Lough Derg anglers that the Asian clam was now being found in the lake and would colonise the entire waterway within a decade.
He was speaking at a meeting on the Lough Derg Native Fish Biodiversity Project, a study of the lake's fish stock that has been ongoing since 2006.
The Asian clam is also found in the River Barrow and Dr Minchin has raised the alert over it appearing n the River Suir.
Both Lough Derg and the Suir have recently been named as Blueways for boating tourism, and there are fears the species could spread through people from outside coming in to avail of the amenities.
Dr Minchin emphasised the need for vigilance, good monitoring and good practices by river and lake users to reduce the threat of the spread of these alien species.
Most aquatic invasive species were spread by boats and activities associated with water such as angling, and that there is a need for a greater understanding on how their spread can be avoided. It is estimated that the cost of invasive species to the Irish economy is in excess of €230 per annum and rising. In the UK, it is multiples of this.
Meanwhile, Dr Fran Igoe of the Lough Derg project, said that were simple methods to ensure that the risk of transfer of invasive aquatic species was reduced. Simply washing boats, canoes, kayaks, angling keepnets in hot water and drying them out is enough to significantly reduce the risk. Ideally disinfectant detergents should be used and there is plenty of information online on how to do this.
He said the big concern for the River Suir was to ensure that species such as the highly invasive Asian clam, which clogs up fish spawning gravel beds, did not make an appearance in the river.
Once the clam enters a waterway, there is no stopping it as it can distribute itself much in the same way as young spiders travel through air on gossamer threads. Young Asian clams do something similar underwater so once they enter a Blueway, they can spread very quickly indeed, bringing with them serious problems for native species and the local fishing economy.
Lough Derg has already suffered from an invasion of zebra mussels as well as some species of non-native shrimp.