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Displaying items by tag: Salmon Smolts

#Salmon - Wild Atlantic salmon smolts migrating to sea from Irish rivers can become infected with sea lice from West Coast salmon farms and suffer increased mortality soon after leaving the coast, cutting their numbers by half.

That’s the conclusion of a new study published in international journal Aquaculture Environment Interactions, which used 30 years of data from the River Erriff in the West of Ireland to evaluate the effect of sea lice from salmon aquaculture on wild Atlantic salmon.

The study, titled ‘Quantifying the contribution of sea lice from aquaculture to declining annual returns in a wild Atlantic salmon population’, examined sea lice production from salmon farming in Killary Harbour and its effect on the return of wild salmon to the Erriff, at the head of the harbour, in the following year.

Results from this long-term study indicate that returns of wild adult salmon can be reduced by more than 50% in years following high lice levels on nearby salmon farms during the smolt out-migration.

Inland Fisheries Ireland says sea lice from salmon farming have long been implicated in the collapse of sea trout stocks along the West Coast.

But this latest study, authored by Dr Samuel Shephard and Dr Paddy Gargan from IFI, is “the first to clearly demonstrate significant losses of wild Atlantic salmon due to infestation with sea lice from salmon farms,” it adds.

Dr Shephard says: “There has been a lot of discussion as to the importance of the sea lice impact in the context of environmental variation and changing ocean conditions.

“We find that the predicted 50% reduction in 1SW salmon returns following a high lice year is greater than the average year-to-year variation attributable to environmental effects.”

Modelled lice impact levels and a fitted stock-recruitment relationship were used to estimate how annual returns of Erriff salmon might have looked over the last 30 years, in the absence of a serious impact of sea lice from aquaculture.

Results suggest that Erriff salmon returns could now be twice as large as without observed anthropogenic lice impacts, but would probably show a similar long-term decline.

The River Erriff is designated as a Special Area of Conservation (SAC) for Atlantic salmon under the European Union Habitats Directive (92/43/EEC). Salmon smolts from the Erriff can be followed via a new online tool, as previously reported on Afloat.ie.

Dr Gargan explained that increased mortality of wild salmon due to the impact of sea lice can result in salmon stocks not reaching spawning targets or not being at favourable conservation status as required under the EU Habitats Directive.

It is therefore critical that sea lice levels are maintained at a very low level on farmed salmon in spring – and where this has not been achieved, that farmed fish are harvested before the wild salmon smolt migration period.

The authors conclude: “Many Atlantic salmon populations are already under pressure from (possibly climate-mediated) reductions in marine survival. The addition of significant lice-related mortality during the coastal stage of smolt out-migration could be critical.”

The full report can be found HERE.

Published in Marine Wildlife

#SalmonSmolts - Inland Fisheries Ireland (IFI) has launched the SMOLTRACK project, which gives the public the opportunity to follow the numbers of juvenile salmon making their journey down the River Erriff.

The EU-funded NASCO project will see IFI work alongside partners in Northern Ireland (River Bush), England (River Tamar), Spain (River Ulla and River Tea) and Denmark (River Skjern) in rolling out a counting, tagging and tracking system.

Traps are used to catch migrating salmon smolts for tagging before releasing them to continue their migration journey. In order to provide stakeholders – angling enthusiasts included – with the opportunity to follow and compare the migration timing of smolts in several countries, the daily numbers of salmon smolts counted in each system is uploaded for online viewing.

In Ireland, tagging is being carried out on salmon smolts from the Black River, a tributary of the River Erriff, which itself is the National Salmonid Index Catchment (NSIC).

The Erriff in Co Mayo is one of the premier salmon fishing rivers in Ireland and its smolt run typically occurs over six weeks during April and May. This year, the smolt run commenced on the river on Monday 3 April, with 289 salmon smolts counted on the system as of today (Monday 24 April).

The salmon smolts are tagged with miniature acoustic transmitters and their subsequent migration is followed via acoustic listening stations situated at various locations.

This information will help scientists to understand the survival rates of salmon smolts during their migration through the lower parts of rivers, estuaries and coastal areas, in addition to providing data on smolt run timing and migration behaviour.

The project will provide new data which will inform future salmon management and conservation work.

“This is an exciting project which will allow us to gather new information around the survival and timing of salmon smolts journeying seaward through the River Erriff, and into and through inshore coastal waters,” says Dr Cathal Gallagher, IFI’s head of research and development.

“We look forward to determining more about the smolts once they have been tagged by following their migration journey. As we are working with partners in Northern Ireland, England, Spain and Denmark, we can also learn from the data gathered in their regions.

“Ultimately, this information will inform our work in the area of salmon conservation which will prove invaluable to Ireland’s fisheries resource in the long term.”

Published in Angling

Marine Protected Areas (MPAs) - FAQS

Marine protected areas (MPAs) are geographically defined maritime areas where human activities are managed to protect important natural or cultural resources. In addition to conserving marine species and habitats, MPAs can support maritime economic activity and reduce the effects of climate change and ocean acidification.

MPAs can be found across a range of marine habitats, from the open ocean to coastal areas, intertidal zones, bays and estuaries. Marine protected areas are defined areas where human activities are managed to protect important natural or cultural resources.

The world's first MPA is said to have been the Fort Jefferson National Monument in Florida, North America, which covered 18,850 hectares of sea and 35 hectares of coastal land. This location was designated in 1935, but the main drive for MPAs came much later. The current global movement can be traced to the first World Congress on National Parks in 1962, and initiation in 1976 of a process to deliver exclusive rights to sovereign states over waters up to 200 nautical miles out then began to provide new focus

The Rio ‘Earth Summit’ on climate change in 1992 saw a global MPA area target of 10% by the 2010 deadline. When this was not met, an “Aichi target 11” was set requiring 10% coverage by 2020. There has been repeated efforts since then to tighten up MPA requirements.

Marae Moana is a multiple-use marine protected area created on July 13th 2017 by the government of the Cook islands in the south Pacific, north- east of New Zealand. The area extends across over 1.9 million square kilometres. However, In September 2019, Jacqueline Evans, a prominent marine biologist and Goldman environmental award winner who was openly critical of the government's plans for seabed mining, was replaced as director of the park by the Cook Islands prime minister’s office. The move attracted local media criticism, as Evans was responsible for developing the Marae Moana policy and the Marae Moana Act, She had worked on raising funding for the park, expanding policy and regulations and developing a plan that designates permitted areas for industrial activities.

Criteria for identifying and selecting MPAs depends on the overall objective or direction of the programme identified by the coastal state. For example, if the objective is to safeguard ecological habitats, the criteria will emphasise habitat diversity and the unique nature of the particular area.

Permanence of MPAs can vary internationally. Some are established under legislative action or under a different regulatory mechanism to exist permanently into the future. Others are intended to last only a few months or years.

Yes, Ireland has MPA cover in about 2.13 per cent of our waters. Although much of Ireland’s marine environment is regarded as in “generally good condition”, according to an expert group report for Government published in January 2021, it says that biodiversity loss and ecosystem degradation are of “wide concern due to increasing pressures such as overexploitation, habitat loss, pollution, and climate change”.

The Government has set a target of 30 per cent MPA coverage by 2030, and moves are already being made in that direction. However, environmentalists are dubious, pointing out that a previous target of ten per cent by 2020 was not met.

Conservation and sustainable management of the marine environment has been mandated by a number of international agreements and legal obligations, as an expert group report to government has pointed out. There are specific requirements for area-based protection in the EU Marine Strategy Framework Directive (MSFD), the OSPAR Convention, the UN Convention on Biological Diversity and the UN Sustainable Development Goals. 

Yes, the Marine Strategy Framework directive (2008/56/EC) required member states to put measures in place to achieve or maintain good environmental status in their waters by 2020. Under the directive a coherent and representative network of MPAs had to be created by 2016.

Ireland was about halfway up the EU table in designating protected areas under existing habitats and bird directives in a comparison published by the European Commission in 2009. However, the Fair Seas campaign, an environmental coalition formed in 2022, points out that Ireland is “lagging behind “ even our closest neighbours, such as Scotland which has 37 per cent. The Fair Seas campaign wants at least 10 per cent of Irish waters to be designated as “fully protected” by 2025, and “at least” 30 per cent by 2030.

Nearly a quarter of Britain’s territorial waters are covered by MPAs, set up to protect vital ecosystems and species. However, a conservation NGO, Oceana, said that analysis of fishing vessel tracking data published in The Guardian in October 2020 found that more than 97% of British MPAs created to safeguard ocean habitats, are being dredged and bottom trawled. 

There’s the rub. Currently, there is no definition of an MPA in Irish law, and environment protections under the Wildlife Acts only apply to the foreshore.

Current protection in marine areas beyond 12 nautical miles is limited to measures taken under the EU Birds and Habitats Directives or the OSPAR Convention. This means that habitats and species that are not listed in the EU Directives, but which may be locally, nationally or internationally important, cannot currently be afforded the necessary protection

Yes. In late March 2022, Minister for Housing Darragh O’Brien said that the Government had begun developing “stand-alone legislation” to enable identification, designation and management of MPAs to meet Ireland’s national and international commitments.

Yes. Environmental groups are not happy, as they have pointed out that legislation on marine planning took precedence over legislation on MPAs, due to the push to develop offshore renewable energy.

No, but some activities may be banned or restricted. Extraction is the main activity affected as in oil and gas activities; mining; dumping; and bottom trawling

The Government’s expert group report noted that MPA designations are likely to have the greatest influence on the “capture fisheries, marine tourism and aquaculture sectors”. It said research suggests that the net impacts on fisheries could ultimately be either positive or negative and will depend on the type of fishery involved and a wide array of other factors.

The same report noted that marine tourism and recreation sector can substantially benefit from MPA designation. However, it said that the “magnitude of the benefits” will depend to a large extent on the location of the MPA sites within the network and the management measures put in place.

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