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Displaying items by tag: Owenriff Catchment

#Angling - Inland Fisheries Ireland has published its 2017 fish stock survey for the Owenriff catchment as well as its rehabilitation plan for the system to promote the recovery of brown trout and salmon in its lakes and rivers.

The Fish Stock Survey — which was conducted in the summer of 2017 and forms the basis for the Rehabilitation Plan — deduces that the introduction of pike into the catchment has been the significant factor in the declining fish stocks.

“As there are little or no major anthropogenic pressures in the catchment to cause the decline in fish stocks, it is reasonable to infer that the introduction of pike and their subsequent range expansion in the Owenriff catchment (with impacts of competition for food and space and predation on resident and migratory fish) is the main factor causing the decline of brown trout and salmon in the Owenriff catchment. Research from Europe and North America supports this finding,” the reports states.

Anthropogenic pressures include human-induced factors such as urban growth, deleterious discharges, farming activities and introduction of alien species.

Although pike were captured for the first time by IFI staff in 2009 in two lakes in the catchment (Loughs Bofin and Agraffard) and efforts were made by IFI staff to remove the pike from the system, they did not show up in two catchment-wide surveys in 1997 and 2007 and were only officially recorded in a survey for the first time in 2015.

However, the latest report, from the 2017 survey, confirms that pike are present all over the Owenriff catchment “in areas where they can freely gain access and in some areas where they cannot naturally gain access.”

Welcoming the publication of the two reports, Minister Sean Kyne TD said: “We have acted swiftly since the interim results of this survey became known. In late January, I announced that Inland Fisheries Ireland is to commence fish stock management operations on the Owenriff catchment to protect and restore trout stocks which have been impacted by recent introductions of pike to the catchment.

“The consequences of not taking wider remedial action on the basis of these survey results would lead to further decline in ecological biodiversity in the catchment, so I very much welcome the publication by IFI of the Owenriff Fish Population Rehabilitation Plan 2018.”

The minister continued: “The purpose of the plan is to develop a fisheries rehabilitation project that can be undertaken on the catchment to promote the recovery of the brown trout (both resident and migratory Corrib) and salmon populations in both lakes and rivers. It will take time and will be costly, but we are already underway with this very constructive and positive roadmap.”

With stock management actions having already commenced, the success of the broader rehabilitation project will depend on applying the correct tools to rehabilitate the brown trout and salmon populations in the Owenriff catchment.

These include fisheries enhancement works in selected sub-catchments to favour brown trout and salmon; genetic restoration; removing the problem (pike control); reducing anthropogenic impacts in the catchment; public awareness (especially in relation to the impacts of the introductions of species not indigenous to an area); interagency co-ordination; climate change mitigation; and any other necessary measures.

The Owenriff catchment is located on the north-western end of the Lough Corrib catchment, and the main Owenriff River drains into Lough Corrib Upper downstream of Oughterard, Co Galway. The Lough Corrib catchment itself is the largest and most important wild salmonid catchment in Ireland, and Lough Corrib is considered the premier wild brown trout fishery in Ireland.

The Owenriff rehabilitation plan and 2017 fish stock survey can both be downloaded from the IFI website. Afloat.ie also has more on IFI's stock management plan for Ireland's trout waters in 2018.

Published in Angling

#Angling - Sean Kyne, Minister of State with responsibility for the inland fisheries sector, has announced that Inland Fisheries Ireland will shortly commence fish stock management operations on the Owenriff catchment near Oughterard in Co Galway.

The measures to protect and restore trout stocks, which have been impacted by recent introductions of pike to the catchment, were promised last November upon the development by IFI of a specific stock management plan.

“The Owenriff catchment is one of the most important spawning and nursery tributaries of Lough Corrib, our most renowned wild trout fishery,” said Minister Kyne as he made the announcement today (Monday 29 January).

“Previous scientific studies have shown it contributed 15% of the wild trout found in Lough Corrib, and each year thousands of wild trout and salmon migrate upstream into the Owenriff to spawn.

“I am committed to protecting and rehabilitating the system and welcome IFI’s stock management plan which I have asked to be implemented immediately.”

IFI will be commencing a focused and intensive effort aimed at reducing the numbers of pike in the Owenriff catchment over the coming year.

While pike cannot be completely eradicated, the project will reduce numbers to a level where they are not impacting significantly on salmonid stocks.

It is expected that ongoing maintenance operations will be required in future years to help maintain the trout population.

Minister Kyne also emphasised that, in tandem with the stock management plan, IFI is also preparing an Owenriff Fish Population Rehabilitation Plan which aims to ensure trout stocks and habitats are restored and protected, thereby providing the best opportunities for a successful trout population. The plan will be available shortly.

Survey results are currently being compiled and will be available from the IFI website. Further information on the stock management plan is available HERE.

Published in Angling

Sharks in Irish waters

Irish waters are home to 71 species of shark, skates and rays, 58 of which have been studied in detail and listed on the Ireland Red List of Cartilaginous fish. Irish sharks range from small Sleeper sharks, Dogfish and Catsharks, to larger species like Frilled, Mackerel and Cow sharks, all the way to the second largest shark in the world, the Basking shark. 

Irish waters provide a refuge for an array of shark species. Tralee Bay, Co. Kerry provides a habitat for several rare and endangered sharks and their relatives, including the migratory tope shark, angel shark and undulate ray. This area is also the last European refuge for the extremely rare white skate. Through a European Maritime and Fisheries Fund (EMFF) project, Marine Institute scientists have been working with fishermen to assess the distribution, diversity, and monthly relative abundance of skates and rays in Tralee, Brandon and Dingle Bays.

“These areas off the southwest coast of Ireland are important internationally as they hold some of the last remaining refuges for angel shark and white skate,” said Dr Maurice Clarke of the Marine Institute. “This EMFF project has provided data confirming the critically endangered status of some species and provides up-to-date information for the development of fishery measures to eliminate by-catch.” 

Irish waters are also home to the Black Mouthed Catshark, Galeus melastomus, one of Ireland’s smallest shark species which can be found in the deep sea along the continental shelf. In 2018, Irish scientists discovered a very rare shark-nursery 200 nautical miles off the west coast by the Marine Institute’s ROV Holland 1 on a shelf sloping to 750 metres deep. 

There are two ways that sharks are born, either as live young or from egg casings. In the ‘case’ of Black Mouthed Catsharks, the nursery discovered in 2018, was notable by the abundance of egg casings or ‘mermaid’s purses’. Many sharks, rays and skate lay eggs, the cases of which often wash ashore. If you find an egg casing along the seashore, take a photo for Purse Search Ireland, a citizen science project focusing on monitoring the shark, ray and skate species around Ireland.

Another species also found by Irish scientists using the ROV Holland 1 in 2018 was a very rare type of dogfish, the Sail Fin Rough Shark, Oxynotus paradoxus. These sharks are named after their long fins which resemble the trailing sails of a boat, and live in the deep sea in waters up to 750m deep. Like all sharks, skates and rays, they have no bones. Their skeleton is composed of cartilage, much like what our noses and ears are made from! This material is much more flexible and lighter than bone which is perfect for these animals living without the weight of gravity.

Throughout history sharks have been portrayed as the monsters of the sea, a concept that science is continuously debunking. Basking sharks were named in 1765 as Cetorhinus maximus, roughly translated to the ‘big-nosed sea monster’. Basking sharks are filter feeders, often swimming with their mouths agape, they filter plankton from the water.

They are very slow moving and like to bask in the sun in shallow water and are often seen in Irish waters around Spring and early Summer. To help understand the migration of these animals to be better able to understand and conserve these species, the Irish Basking Shark Group have tagged and mapped their travels.

Remarkably, many sharks like the Angel Shark, Squatina squatina have the ability to sense electricity. They do this via small pores in their skin called the ‘Ampullae of Lorenzini’ which are able to detect the tiny electrical impulses of a fish breathing, moving or even its heartbeat from distances of over a kilometre! Angel sharks, often referred to as Monkfish have a distinctively angelic shape, with flattened, large fins appearing like the wings of an angel. They live on the seafloor in the coastal waters of Ireland and much like a cat are nocturnal, primarily active at night.

The intricate complexity of shark adaptations is particularly noticeable in the texture of their skin. Composed of miniscule, perfectly shaped overlapping scales, the skin of shark provides them with protection. Often shark scales have been compared to teeth due to their hard enamel structure. They are strong, but also due to their intricate shape, these scales reduce drag and allow water to glide past them so that the shark can swim more effortlessly and silently. This natural flawless design has been used as inspiration for new neoprene fabric designs to help swimmers glide through the water. Although all sharks have this feature, the Leafscale Gulper Shark, Centrophorus squamosus, found in Ireland are specifically named due to the ornate leaf-shape of their scales.