Displaying items by tag: control

17th April 2012

Trial Dredging to Help Rid Barrow of Invasive Asian Clam

#INLAND WATERWAYS - Trial dredging operations to curtail the spread of Asian clams at designated sites in the lower River Barrow are set to conclude today.

Inland Fisheries Ireland (IFI) employed the use of a a traditional cockle harvesting boat to physically remove the clams from the river bed, in an effort to explore methods of controlling or eradicating what it describes as an "ecosystem-changing invader" in other infested waters.

IFI scientists supervised the trials, using teams of divers to quantify the result of the dredging efforts.

The Asian clam (Corbicula fluminea) is "a most unwelcome addition to the fauna of the lower River Barrow". The bivalve mollusc is regarded as "one of the most notorious aquatic invasive species in the world".

First recorded in the river downstream of St Mullin’s in April 2010, subsequent IFI studies have revealed that the Asian clam is firmly established in the lower Barrow and in the River Nore downstream of Inistioge. Populations have also been recorded in the River Shannon and in Lough Derg.

In one section of the River Barrow the clam has achieved a "staggering" density of almost 10,000 per square metre.

Dr Joe Caffrey, senior scientist with IFI, said of the trial dregding: “It is imperative that every effort is made to control the expansion and spread of this highly adept invasive species.

"The results from these trials will inform future national management plans for this most unwelcome non-native species and will, at the very least, dramatically reduce the numbers of individuals in the test sites.

He added: "In tandem with these trials, research effort is being focused at producing other control methods that can be targeted as this species.”

Published in Inland Waterways

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Forty Foot Swimming Spot on Dublin Bay

The 'Forty Foot' is a rocky outcrop located at the southern tip of Dublin Bay at Sandycove, County Dublin from which people have been swimming in the Irish Sea all year round for 300 years or more. It is popular because it is one of few spots between Dublin city and Greystones in County Wicklow that allows for swimming at all stages of the tide, subject to the sea state.

Forty Foot History

Traditionally, the bathing spot was exclusively a men's bathing spot and the gentlemen's swimming club was established to help conserve the area.

Owing to its relative isolation and gender-specific nature it became a popular spot for nudists, but in the 1970s, during the women's liberation movement, a group of female equal-rights activists plunged into the waters and now it is also open to everyone and it is in the control of Dun Laoghaire Rathdown County Council.

Many people believe that swimming in extremely cold water is healthy and good for the immune system.

Is it safe to swim at the Forty Foot?

The Forty-Foot is a great place to swim because there is always enough water to get a dip but like all sea swimming, there are always hazards you need to be aware of. For example, a lot of people like to dive into to the pool at the Forty-foot but there are submerged rocks that can be hazardous especially at low water. The Council have erected signs to warn people of the underwater dangers. Other hazards include slippy granite cut stone steps that can often be covered with seaweed and of course marine wildlife including jellyfish that make their presence felt in the summer months as do an inquisitive nearby Sandycove seal colony.