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Dublin Bay Boating News and Information

Displaying items by tag: Japanese Kelp

Scientists from NUI Galway and Seasearch Ireland are asking divers and marina users to keep an eye out for Undaria pinnatifida, commonly known as Wakame or Japanese kelp. This species was first recorded in Belfast Lough, Northern Ireland in 2012, Wakame has subsequently been recorded at Carlingford Lough in 2014 and Kilmore Quay in Wexford in 2016.

Since then it has been recorded by Seasearch diver Frances O'Sullivan of the Dalkey Sub Aqua club recorded it in Dun Laoghaire Harbour in 2017 and by Seasearch Ireland and KelpRes divers at Greystones Harbour in 2020. Given the widespread nature of the records on the east coast, it is thought that the species is likely to occur in suitable habitats between these areas and may have spread to other areas of the coast.

Wakame can be distinguished from other kelp species found in Ireland by the undulating margins of the blade, distinctive midrib, and belt-like stipe that often has reproductive sori at the margins. The distinctive midrib in a large blade distinguishes this species from other kelp species in Irish waters (e.g. dabberlocks - Alaria esculenta -which has a distinctive midrib but thin blade).

Seasearch Ireland and the KelpRes team at NUIG are asking any marine users who see a kelp species matching the description below to send a photo to [email protected] to confirm the identification and then our colleagues from the KelpRes team in NUIG intend to collect samples of the seaweed for genetic analysis.

Undaria pinnatifida, commonly known as Wakame or Japanese kelp identificationUndaria pinnatifida, commonly known as Wakame or Japanese kelp identification

Kathryn Schoenrock-Rossiter explains the rationale for the sampling: "Studying the genetics of invasive species is important in terms of identifying vectors for introduction and spread. For example, in the invasive freshwater Zebra mussels (Dreissena polymorpha) a study combing genetic analysis with fieldwork revealed leisure boats from the United Kingdom as the most likely source (vector) of introduction. By using genetic tools to investigate Wakame populations we can estimate whether a single introduction event or multiple have occurred and potentially determine where from (e.g. Europe)."

Rory O'Callaghan, Seasearch Ireland: "International experience with wakame would indicate it is much more likely to occur in marinas and on other man-made structures. From here it can attach to boats and be carried to other parts of the country when boats are moved. As divers, we are particularly conscious of the need for good biosecurity practices such as cleaning or drying out their boat before moving it to another location."

Seasearch is a project by the Marine Conservation Society for divers and snorkelers, who have an interest in what they're seeing underwater, want to learn more and want to help protect the marine environment around the coasts of Britain and Ireland.

Published in Marine Science

Dublin Bay

Dublin Bay on the east coast of Ireland stretches over seven kilometres, from Howth Head on its northern tip to Dalkey Island in the south. It's a place most Dubliners simply take for granted, and one of the capital's least visited places. But there's more going on out there than you'd imagine.

The biggest boating centre is at Dun Laoghaire Harbour on the Bay's south shore that is home to over 1,500 pleasure craft, four waterfront yacht clubs and Ireland's largest marina.

The bay is rather shallow with many sandbanks and rocky outcrops, and was notorious in the past for shipwrecks, especially when the wind was from the east. Until modern times, many ships and their passengers were lost along the treacherous coastline from Howth to Dun Laoghaire, less than a kilometre from shore.

The Bay is a C-shaped inlet of the Irish Sea and is about 10 kilometres wide along its north-south base, and 7 km in length to its apex at the centre of the city of Dublin; stretching from Howth Head in the north to Dalkey Point in the south. North Bull Island is situated in the northwest part of the bay, where one of two major inshore sandbanks lie, and features a 5 km long sandy beach, Dollymount Strand, fronting an internationally recognised wildfowl reserve. Many of the rivers of Dublin reach the Irish Sea at Dublin Bay: the River Liffey, with the River Dodder flow received less than 1 km inland, River Tolka, and various smaller rivers and streams.

Dublin Bay FAQs

There are approximately ten beaches and bathing spots around Dublin Bay: Dollymount Strand; Forty Foot Bathing Place; Half Moon bathing spot; Merrion Strand; Bull Wall; Sandycove Beach; Sandymount Strand; Seapoint; Shelley Banks; Sutton, Burrow Beach

There are slipways on the north side of Dublin Bay at Clontarf, Sutton and on the southside at Dun Laoghaire Harbour, and in Dalkey at Coliemore and Bulloch Harbours.

Dublin Bay is administered by a number of Government Departments, three local authorities and several statutory agencies. Dublin Port Company is in charge of navigation on the Bay.

Dublin Bay is approximately 70 sq kilometres or 7,000 hectares. The Bay is about 10 kilometres wide along its north-south base, and seven km in length east-west to its peak at the centre of the city of Dublin; stretching from Howth Head in the north to Dalkey Point in the south.

Dun Laoghaire Harbour on the southside of the Bay has an East and West Pier, each one kilometre long; this is one of the largest human-made harbours in the world. There also piers or walls at the entrance to the River Liffey at Dublin city known as the Great North and South Walls. Other harbours on the Bay include Bulloch Harbour and Coliemore Harbours both at Dalkey.

There are two marinas on Dublin Bay. Ireland's largest marina with over 800 berths is on the southern shore at Dun Laoghaire Harbour. The other is at Poolbeg Yacht and Boat Club on the River Liffey close to Dublin City.

Car and passenger Ferries operate from Dublin Port to the UK, Isle of Man and France. A passenger ferry operates from Dun Laoghaire Harbour to Howth as well as providing tourist voyages around the bay.

Dublin Bay has two Islands. Bull Island at Clontarf and Dalkey Island on the southern shore of the Bay.

The River Liffey flows through Dublin city and into the Bay. Its tributaries include the River Dodder, the River Poddle and the River Camac.

Dollymount, Burrow and Seapoint beaches

Approximately 1,500 boats from small dinghies to motorboats to ocean-going yachts. The vast majority, over 1,000, are moored at Dun Laoghaire Harbour which is Ireland's boating capital.

In 1981, UNESCO recognised the importance of Dublin Bay by designating North Bull Island as a Biosphere because of its rare and internationally important habitats and species of wildlife. To support sustainable development, UNESCO’s concept of a Biosphere has evolved to include not just areas of ecological value but also the areas around them and the communities that live and work within these areas. There have since been additional international and national designations, covering much of Dublin Bay, to ensure the protection of its water quality and biodiversity. To fulfil these broader management aims for the ecosystem, the Biosphere was expanded in 2015. The Biosphere now covers Dublin Bay, reflecting its significant environmental, economic, cultural and tourism importance, and extends to over 300km² to include the bay, the shore and nearby residential areas.

On the Southside at Dun Laoghaire, there is the National Yacht Club, Royal St. George Yacht Club, Royal Irish Yacht Club and Dun Laoghaire Motor Yacht Club as well as Dublin Bay Sailing Club. In the city centre, there is Poolbeg Yacht and Boat Club. On the Northside of Dublin, there is Clontarf Yacht and Boat Club and Sutton Dinghy Club. While not on Dublin Bay, Howth Yacht Club is the major north Dublin Sailing centre.

© Afloat 2020