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19th February 2012

Results of Genetic Studies of Brown Trout Stocks in Suir and Boyne Catchments

#INLAND WATERWAYS - Inland Fisheries Ireland (IFI) has announced the results of studies on the genetic makeup of brown trout stocks in the Suir and Boyne river catchments.

These studies form part of a wider scheme looking at Ireland's larger riverine catchments - assisted by the Office of Public Works, geneticists from UCD and trout anglers across Ireland - and involve a chemical analysis of scale samples from fish known as 'micro-satellite DNA analysis'.

The results from the Suir and Boyne are described by IFI as "quite amazing" and "of significant value" to managing the fisheries in these areas.

In both catchments, the first step saw trout stock samples of young fish examined genetically, and they were shown to be discrete - in other words, fish from any given tributary were found to be genetically different to those from others.

The next step involved samples of adult fish from the main river, contributed by anglers, which were then related to the different tributary genetic types.

Summary results from the Suir and Boyne show that there are respectively seven and five distinct families of trout in the catchment area; that most fish born in tributaries migrate to the main stem till adulthood before returning to their tributaries to spawn; that numbers migrating from individual tributaries are variable, but fish don't cross into adjacent catchment areas; and that there movement of young trout along the river system is "extraordinary", with fish often migrating from near the source to the mouth.

More details on findings for the Suir catchment and Boyne catchment are available on the IFI website.

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.