Recent Submissions

  • Catch and bycatch in the tangle net fishery for crayfish (Palinurus elephas) off the south west coast of Ireland

    Tully, Oliver; Palma-Pedraza, S. (Marine Institute, 2022)
    Crayfish or spiny lobster is fished off the south west coast of Ireland. There are also smaller fisheries on the west and north west coasts. Although historically, prior to the 1970s, the main fishing gear used in the fishery was top entrance traps crayfish are now targeted with large mesh tangle nets. The selectivity of these nets is poor and there is known to be a by-catch of finfish, skates and rays and protected species such as grey seal. The fishery usually occurs from mid-March to December. The species composition and size distribution of the catch and by-catch was surveyed over a 4 year period from 2017-2020 from Dingle Bay north to the Shannon Estuary. Additional data south of this area was obtained in 2020. A crayfish tagging programme was undertaken in 2017 and 2018. Between 2 and 6 vessels participated in the programme depending on year Most of the data was reported directly by Skippers and crew who were contracted to supply data. Scientific observers covered a proportion of trips in 2017 and 2019. A total of 1500 nmiles of tangle net hauls were surveyed across 6 vessels. A total of 11792 crayfish and 899 lobsters were measured, 1234 crayfish were tagged and released and 45 recaptures were reported. Spider crab, brown crab and crayfish were the numerically dominant species in the catch. Lobster, pollack, thornback ray, spurdog, monkfish and turbot were caught regularly in low numbers. There was no cetacean by-catch. A total of 200 grey seals were caught over the 4 year period by the vessels participating in the survey. Endangered and critically endangered species, including flapper skate, common skate, angel shark and white skate, were caught in very low numbers. The finfish catch is mainly lost to scavengers or seal depredation before nets are retrieved and because of long soak times which averaged 8 days. This reduces the value of the catch. The average value of the live crustacean (crayfish, lobster, brown crab) catch was approximately €300 per mile of net hauled. Crayfish were tagged and released in 2017 and 2018 and recaptured during the period 2017-2020. Three crayfish tagged by IFREMER off Brittany in 2015 and 2016 were recaptured off the south west and west coast of Ireland in 2019. The northern most recapture was off Erris Head Co. Mayo. The tagging data shows that most crayfish were recaptured locally close to release points even in the years following tagging. It is still unclear if crayfish are resident or if they migrate in and out of the tagging area as the reporting rate of recaptures outside the tagging area is unknown. The by-catch of critically endangered species poses a high risk to the continued presence of these species in Irish waters and indeed in European waters given that the area is known to hold the last European remnant populations of species such as angel shark and white skate. Grey seal by-catch was related to the distance between the fishing event and the nearest seal colony haul out at the Blasket Islands. Sixty % of seals were caught within 10km of the haul out. The probability of capture in a single net haul declined from 30-35% within 10km to 9-14% at distances of 10-30km to 4% at distances of 40-60km and zero at distances greater than 60km (data for 39 hauls >60km). The high by-catch of grey seal is a significant risk to the Blasket Island seal colony. It is unlikelythat the Blasket population can sustain this level of by-catch mortality without inward migration fromother colonies.
  • The Biologically Sensitive Area: A review of the basis and effectiveness

    APEM (Marine Institute, 2021)
    The Biologically Sensitive Area (BSA) designation is a multiuse area of protection to the south and west of Ireland. The BSA was established within a political context based on three core ideas, namely: (1) to prevent overfishing, (2) protect hake stocks and (3) protect spawning and nursery areas found in this area. The area was established in 2003 to limit fishing within the area, and replaced the previous larger ‘Irish Box’ which had surrounded Ireland.
  • Underwater Television Survey Marine Mammal Observer Report RV Tom Crean 13 – 23 August 2022

    Perez Tadeo, M. (Marine Institute, 2022)
    The Underwater Television Survey (UWTV) on the Porcupine Bank took place from the 13th to the 23rd of August, 2022 on board the Marine Institute’s R.V. Tom Crean. The research survey covered an area on the Porcupine Bank Nephrops grounds. A marine mammal dedicated survey was carried out by an observer on board following a standard single platform line-transect methodology aiming to collect relative abundance and distribution of marine mammals in the area of interest. The marine mammal survey was conducted during 8 days. The total amount of time the marine mammal observer spent on effort was 64 hours, 1 minute and 1 second. Environmental conditions varied between survey days. Visibility was overall good, with most time spent on effort under visibility 5 (i.e. from 16 to 20 km) accounting for 32.13% and visibility 6 (i.e. >20 km), accounting for 28.44% of the time. On the other hand, sea state conditions were not favourable, since most of the effort was carried out under sea state 5 (45.62% of the time). Swell height was recorded as higher than 2 m during most of the time spent on effort (62.75% of the total time). Marine mammal survey effort was carried out during all days while traveling, with the exception of the 19/08/2022, when effort had to be interrupted due to adverse weather conditions. A total of 10 sightings of marine mammal species were recorded over the course of the survey, with common dolphins accounting for 60% of these sightings.
  • Monitoring the recovery of exploited deep-water species

    Kelly, Eoghan; Gerritsen, Hans D (Marine Institute, 2022)
    Commercial fisheries for deep-water species off the Irish coast developed in the late 1990s and declined in the early 2000s. Many of the exploited stocks were depleted a result of commercial exploitation and ICES has advised a zero catch for Orange Roughy since 2004, and for Portuguese Dogfish and Leafscale Gulper shark since 2005. Since 2016, the deep water access regulation has effectively banned trawling in waters deeper than 800 m (EC, 2016) and fishing for deep-water sharks with static netting >600 m is also banned by the technical measures regulation (EC, 2019). However, some of these species continue to be caught, either by gears not covered by this regulation or in water <800 m deep. The Marine Institute carried out a survey programme to assess the distribution and abundance of these species between 1992 and 1999 and again between 2006 and 2009. Since 2019, 3 days of the Irish Anglerfish and Megrim Survey have been allocated to monitoring the recovery of commercial deep-water species. This work was funded under the European Maritime and Fisheries Fund (EMFF) from 2019 to 2021 and European Maritime, Fisheries and Aquaculture Fund (EMFAF) since 2022. The main objective of the current project is to assess the recovery of exploited deep-water species in Irish waters by comparing the results from 2019 to 2022 surveys with those from the previous period in 2006 to 2009 (methods used in the earlier period 1992 to 1999 were different, therefore a direct comparison with that period is not possible).
  • Supply of Vertebrate Necropsy and Sample Recovery Services Merged Final Reports

    Levesque, Stephanie; O'Donovan, Jim; Daly, Mags; Murphy, Sinéad; O'Connell, Mick; Jepson, Paul; Deaville, Rob; Barnett, James; Berrow, S.D. (Marine Institute, 2021)
    The Marine Institute issued a tender for the Supply of Vertebrate Necropsy and Sample Recovery Services Tender (2017-2018). The results are presented in this report. These tenders required i) the recovery and standardised necropsy of three cetacean species with associated case history reporting, ii) the provision of sampling kits to be used for the recovery of tissue samples collected from bycaught animals (birds, seals and cetaceans) by observers on commercial inshore and offshore fishing vessels in Irish waters in order to provide additional data to the MI’s existing catch sampling programme and iii) the storage and subsequent delivery of all samples and associated databases to the client. Recovery of 24 animals from two geographical lots was the target for the initial contract (2017) and was achieved. The contract extension (early 2018) required the collection and necropsy of a further 16 animals, which was exceeded as 19 animals were collected. A target of 30 animals to be recovered was required in the second contract (2018) and was also successfully reached. These 73 animals comprised 53 common dolphins (Delphinus delphis), ten striped dolphins (Stenella coeruleoalba) and ten harbour porpoises (Phocoena phocoena). Forty-one of the 73 (56%) individuals were recovered from Lot 1 from counties Clare to Donegal, while 32 (44%) individuals were recovered from Lot 2 from counties Wexford to Kerry. Thirty-five sampling kits were assembled and delivered to the Marine Institute, and additional kits were prepared and available upon request for distribution to their panel of fishery observers. Between 24 July and 14 December 2017, two adult male grey seals were incidentally captured in tangle nets and reported to the Project Coordinator. Results from these tenders will inform the development of a long-term strategy for necropsy of stranded cetaceans and recovery of tissue samples for further biological studies. Samples requiring long-term storage at -20°C, including those for virology, were transported in a portable refrigerator to the IWDG office in Kilrush, Co. Clare and stored at facilities on site. Formalin fixed tissues, such as reproductive organs and adrenal glands, were stored at the RVL in Cork. All samples have been delivered to the Marine Institute in Oranmore, Co. Galway along with a detailed database of samples collected.
  • Nephrops and Microplastics

    Joyce, Haleigh; Frias, João; Kavanagh, Fiona; White, Jonathan; Nash, Róisín (Marine Institute, 2022)
    Plastic litter, once introduced into the marine environment can fragment into smaller plastic pieces known as microplastics (MPs) due to weathering and degradation. The ubiquitous nature of MPs has led to an increased focus on commercial seafood species as there is potential for this contaminant to enter the human food chain. Several studies to date have reported MPs in the GIT of the Dublin Bay Prawn, Nephrops norvegicus and the surrounding sedimentary environment. The Dublin Bay prawn, N. norvegicus is one of the most commercially important species landed by the Irish Fleet, worth approximately €37 million in 2020. Due to their high economic value, spatial distribution, and ecological relevance N. norvegicus have the potential to be used as a bioindicator for MP contamination and can be used to provide information to guide policy makers and environmental managers. This research focuses on the MP loadings in N. norvegicus and the exploration of a potential relationship with their surrounding sedimentary habitat within six primary N. norvegicus fishing grounds in the North East Atlantic. While N. norvegicus has been documented to ingest MPs, this research builds on the knowledge base through exploring the ingestion and retention times of MPs of varying sizes. This research proposes a pan-European monitoring programme to detect MP abundances and changes in levels through the use of N. norvegicus as a potential bioindicator for MP contamination.
  • The Distribution and Abundance of Elasmobranch Fish in Tralee, Brandon and Dingle Bays in 2018-2019

    Tully, Oliver; Palma-Pedraza, S.; Clarke, Maurice; Keane, Julie (Marine Institute, 2021)
    Surveys of skates and rays were undertaken in Tralee, Brandon and Dingle Bays in north Kerry during 2018 and 2019. The area was previously shown, from angling records and more recent shore surveys of egg cases, to support a high diversity of these species some of which are critically endangered in Ireland, the Atlantic or globally. Twelve species were recorded in the area and their geographic and seasonal distribution is described in this report. Their relative abundance in the surveys confirms their presence in the Tralee Bay area and the importance of that area as a refuge for them. Three of the species recorded, angel shark, blue skate and flapper skate are critically endangered globally. White skate was not recorded in the surveys but a single individual was captured separately in commercial tangle nets in 2018 in the area. This species is critically endangered in the Atlantic. Data from other broad scale fisheries surveys and fisheries sampling at sea, not reported here, confirm that these species are rarely found elsewhere. In addition, and in order of abundance, thornback ray, painted ray, sting ray, undulate ray, blonde ray, spotted ray, spurdog, tope and greater spotted dogfish were recorded. Endangered species of skates and rays are listed on various species red lists internationally and are prohibited species (from being landed) under Common Fisheries Policy regulations. The main source of mortality is from fishing. The current regulations, however, do not necessarily remove this source of impact because accidental by-catch and mortality can still occur. Populations that are at critically low levels locally are unlikely to be able to sustain this additional mortality and there is an ongoing risk of local extinction. Effective protection and restoration will need to consider additional measures such as marine protected areas or other mitigations of the effects of fisheries where they pose a high risk to the viability of local populations. Waters off north Kerry are important internationally as they hold some of the last remaining refuges for angel shark and white skate.
  • EMFF Coastal Sediments Project – Achill Bay Survey Report

    O'Sullivan, David; INFOMAR (Marine Institute, 2021)
    There is an ongoing requirement for high resolution substrate maps that accurately depict the sediment properties of the seabed and improve our knowledge of the marine environment. This Coastal Sediment Sampling Project, funded by the European Maritime Fisheries Fund (EMFF), will conduct intense sediment sampling and environmental data collection (including video) surveys on areas of interest in Ireland’s coastal waters to develop high resolution sediment maps, create habitat maps and support ancillary EMFF projects coordinated by the Marine Institute. Achill Bay was selected as the first leg of this survey programme as no multibeam data exists within the inner bay and a significant number of sediment samples were required to create accurate seabed classification charts and habitat maps. A strategic sampling campaign will target and retrieve sediment samples for Particle Size Analysis and increase the accuracy of key derived products such as substrate and habitat maps which are key to supporting Ireland’s Marine Spatial Plan, and the Marine Strategy Framework Directive, identified as priority action(s) of the EMFF Operational Programme. The primary aim of this survey was to conduct a ground-truthing sampling survey of Achill Bay and acquire sediment samples from predefined locations. In addition, video ground-truthing will be conducted using a GoPro camera and frame for manual deployment
  • EMFF Coastal Sediments Project – Offshore Sampling Survey Report, December 2021

    O'Sullivan, David; INFOMAR (Marine Institute, 2021)
    There is an ongoing requirement for high resolution substrate maps that accurately depict the sediment properties of the seabed and improve our knowledge of the marine environment. A Coastal Sediment Sampling Project, funded by the European Maritime Fisheries Fund (EMFF) and led by INFOMAR, was established to conduct intense sediment sampling and environmental data collection (including video) surveys on areas of interest in Ireland’s coastal waters to develop high resolution sediment, substrate and habitat maps, increase the accuracy of these key derived products and support ancillary EMFF projects coordinated by the Marine Institute. Furthermore, this strategic campaign will support Ireland’s Marine Spatial Plan, and the Marine Strategy Framework Directive, identified as priority action(s) of the EMFF Operational Programme. This report details the second leg of the EMFF Coastal Sediment Sampling Project which was conducted in offshore coastal waters of the Irish Sea and along Irelands south coast. Five sampling areas were chosen of which three were surveyed, with each area requiring additional sediment data in order to increase the resolution of existing seabed classification charts. The primary aim of this survey was to retrieve sediment samples for Particle Size Analysis from these selected areas to increase the accuracy of relevant substrate and habitat maps.
  • Sensitive Ecosystem Assessment and ROV Exploration of Reef (SeaRover), Synthesis Report

    Picton, B.; Morrow, C.; Scally, L.; Pfeiffer, N.; McGrath, Fergal (Marine Institute, 2021)
    an extensive offshore reef survey of Ireland’s continental slope was commissioned by the Marine Institute in partnership with the National Parks and Wildlife Service (NPWS), funded by the European Maritime and Fisheries Fund (EMFF), and coordinated and led by INFOMAR (Integrated Mapping for the Sustainable Development of Ireland’s Marine Resources). The objectives of the survey were to implement the EMFF’s Marine Biodiversity Scheme - Natura Fisheries, by mapping offshore reef habitats with a view to protecting them from deterioration due to fishing pressures. The reef project aligns with sub-article 6.2 of the Habitats Directive (EC 92/43/EEC) which requires member states to take measures to avoid deterioration of protected habitats. The Sensitive Ecosystem Assessment and ROV Exploration of Reef (SeaRover) survey took place between 2017 to 2019. The 2017 and 2018 surveys took place onboard the ILV Granuaile whilst the third survey leg in 2019 employed the Marine Institute’s RV Celtic Explorer. The Marine Institute’s remotely operated vehicle (ROV) Holland I was used for each of these cruises. The Holland I was equipped with a high-definition (HD) camera, various composite video feeds and a robotic arm for sample collection. The primary aim of the survey was to map the distribution and abundance of biogenic and geogenic reef habitat along Ireland’s continental margin using HD video.