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Dublin Bay Boating News and Information

Displaying items by tag: Algae

Kerry County Council is once again warning pet owners to be vigilant around Lough Leane in Killarney after the detection of blue-green algae, as RTÉ News reports.

Samples taken in recent days show the presence of the algae, which has the potential to form a scum that’s toxic to animals.

Last July pet owners were advised to be vigilant over the presence of Cyanobacteria which has turned the waterway a soupy pea-green colour.

A previous outbreak in 2016 was connected with a number of dog deaths.

RTÉ News has more on the story HERE.

Published in Inland Waterways

#AlgalBloom - The Marine Institute says it is currently monitoring an algal bloom on beaches on the east coast of Ireland as a part of its Phytoplankton Monitoring programme. 

The bloom was detected two weeks ago using satellite images and information provided by the Environmental Protection Agency (EPA) and Wexford County Council.

The Marine Institute has analysed a number of samples from the algal bloom and has identified the species as Phaeocystis pouchetii, a common species that has caused blooms along the east coast several times in previous years. The species causes discolouration of the water, and foaming on the beach in windy conditions.  

Joe Silke of marine environment and food safety services at the Marine Institute emphasised that the species is not directly harmful to humans either through swimming or from consuming fish that have been exposed to the bloom. 

Beaches remain safe despite any discolouration of water, though the production of foam, and in some extreme cases anoxia, can result in marine organism mortalities. 

However, unlike last summer's destructive algal bloom on the west and north coasts that was responsible for significant fish and shellfish kills from Galway to Donegal, fish mortalities caused by this particular species in previous Irish blooms have not been observed, as wild fish tend to avoid the bloom. This may explain the low catches reported by sea anglers on the east coast in recent weeks. 

Several fishermen have also reported clogging of nets in recent weeks, which may be caused by the decaying bloom sinking to the seafloor.  

Algal blooms are commonly detected over the summer months in coastal areas. It is likely that this particular bloom will dissipate in in the next week or so and will be replaced with the normal succession of microalgae that form the bottom of the food chain in the sea.

Published in Marine Wildlife

#MARINE WILDLIFE - An algal bloom off the west coast of Ireland is responsible for significant fish and shellfish kills from Galway to Donegal, according to the Marine Institute.

As The Irish Times reports, as much as 80% of stocks have been affected on Donegal oyster farms, and the bloom is also impacting negatively on angling tourism in the west and northwest.

The algae responsible, karenia mikimotai, occurs naturally in Ireland's coastal waters during the summer months and his harmless to humans, but contains a "toxic irritant" that damages the gills of fish, shellfish and other marine species.

Low-level samples were first detected in May but in the last two weeks it has grown into a dense bloom from Donegal to Mayo, with high levels now being recorded in Galway Bay, according to the Marine Institute's Joe Silke.

"In Donegal the bloom was so dense that there were many reports of discoloured red or brown water in some areas and several areas have reported dead marine life washing up on the shoreline, requiring local authorities to close certain beaches,” he said.

"The bloom affects species that live on or near the sea bed so we are seeing flatfish, lugworms and some shellfish getting washed up on the beaches."

The image evokes memories of the notorious 'red tide' that killed wild fish and shellfish along the west coast in 2005.

Meanwhile, the Marine Insitute said there are "some indications" that the bloom may be moving back out to sea, as observed in the latest satellite images and modelling data.

"However, cell counts of samples analysed in the Marine Institute... show that the bloom is still of the same density in the Donegal and Sligo regions as it was last week."

Published in Marine Wildlife

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