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Acoustic Surveys

Recent Submissions

  • Celtic Sea Herring Acoustic Survey Cruise Report 2023, 09 - 29 October, 2023

    O'Donnell, Ciaran; O’Malley, M.; Mullins, Eugene; Daly, Eoghan; Keogh, Niall; McBride, Lauren (Marine Institute, 2024)
    The primary objectives of this survey were: <br><br> *Carry out a two phase survey cruise track covering the core survey area <br><br> *Carry out additional adaptive surveys as required in areas of interest <br><br> *Collect biological samples from directed trawling on insonified fish echotraces <br><br> * Collect biological data on the age, length and maturity of herring and sprat <br><br> *Determine an age stratified estimate of relative abundance of herring within the survey area (ICES Divisions VIIj, VIIg and VIIaS) <br><br> *Determine an estimate of relative abundance of sprat, anchovy and sardine within the survey area (ICES Divisions VIIj, VIIg and VIIaS) <br><br> *Collect physical oceanography data from vertical profiles from a deployed sensor array <br><br> * Collect biological samples of sprat and herring for genetic analysis on stock origin studies. <br><br> * Visual surveys to determine the distribution and abundance of apex predators (marine mammals, tuna and seabirds)
  • Western European Shelf Pelagic Acoustic Survey (WESPAS) 09 June –20 July, 20223. FSS Survey Series: 2023/03

    O'Donnell, Ciaran; O’Malley, Michael B.; Mullins, Eugene; Whitefield, Jamie (Marine Institute, 2023)
    The WESPAS survey program is the consolidation of two existing survey programs carried out by FEAS, the Malin Shelf herring acoustic survey, and the boarfish acoustic survey. The Malin Shelf herring acoustic survey has been carried out annually since 2008 and reports on the annual abundance of summer feeding aggregations of herring to the west of Scotland and to the north and west of Ireland from 53°30’N to 58°30’N. The boarfish survey was conducted from 2011 using a chartered fishing vessel and reported the abundance of spawning aggregations of boarfish from 47°N to 57°N. In 2016 both surveys were combined into the WESPAS survey and have been carried out on the RV Celtic Explorer over a 42-day period, providing synoptic coverage of shelf waters from 47°30’N northwards to 58°30’N. Age stratified relative stock abundance estimates of boarfish, herring and horse mackerel within the survey area were calculated using acoustic data and biological data from trawl sampling. Stock estimates of boarfish and horse mackerel were submitted to the ICES assessment Working Group for Widely Distributed Stocks (WGWIDE) meeting in August 2022. Herring estimates are submitted to the Herring Assessment Working Group (HAWG) meeting in March every year. Survey performance will be reviewed at the ICES Planning Group meeting for International Pelagic Surveys (WGIPS) meeting in January 2024.
  • Atlantic Herring in 6aS/7b, Industry Acoustic Survey Cruise Report, November-December 2022

    O’Malley, M.; Mullins, Eugene; Nolan, Cormac (Marine Institute, 2023)
    An acoustic survey of Atlantic herring Clupea harengus was conducted in ICES areas 6aS/7b in November/December 2022 and January 2023. The 2022 survey was conducted using five vessels; MFVs Crystal Dawn WD201, Ros Ard SO745, Girl Kate SO427, Johnny G S653 (d) and Conquest SO852. The 6aS/7b survey design in 2022 focused on 6 core areas with prior knowledge of herring distribution from previous surveys and the monitoring fishery were targeted for surveying. The change in survey design since 2020 was largely based on the results from ICES WKHASS (ICES 2020) and from lessons learned in the previous surveys in this area from 2016-2019. This design resulted in a much reduced survey area compared to previous years, but with better coverage of most of the important inshore bays where the monitoring fishery takes place. The survey design objective remained the same; to capture the distribution of winter spawning herring in the 6aS/7b area, but this design was not expected to achieve overall stock containment. The timing of surveys in the core areas was flexible from the outset by design. The greater flexibility allows for a targeted spatial and temporal approach which avoided the inevitable poor weather that can happen in this area during this time of the year and which led to reduced survey effort in some previous years. Using smaller vessels allowed surveys to be conducted in shallow inshore areas where herring are known to aggregate during this time of the year. This survey is the seventh consecutive annual acoustic survey for pre-spawning herring in this area at this time of the year. A pole-mounted system with a combi 38 kHz (split) 200 kHz (single) transducer was used successfully for the survey on small vessels (<18m) in 2022. Herring were again distributed inshore in shallow areas, and the improved survey design and use of small vessels for the survey resulted in a good measure of uncertainty (CV =0.25). The stock was not overall contained in 2022, particularly in the Donegal Bay area (Malin Beg, etc.) and more effort is required to target surveys earlier and later than December and January when herring tend to show up in these areas in difficult to predict patterns. Very strong herring marks were evident in Lough Foyle and Lough Swilly in the channel in marks that extended for many miles in some cases. This was in areas where smaller boats in the fishery were concentrating effort. Herring had left the Swilly and Foyle by mid-February. There was also a series of strong herring marks in Bruckless Bay, Fintra Bay and Inver Bay in discreet areas, particularly in December. The monitoring fishery was being conducted on smaller boats in the same areas and close to the same time as the survey and biological samples from some of these vessels were used. There was a fairly tight distribution of length classes in all hauls, with most hauls dominated by larger (> 22 cm) mature fish. The 2- and 3-wr age class of herring accounted for 72% of the overall numbers in 2022. The total stock biomass (TSB) estimate of 54,046 tonnes is considered to be a minimum estimate of herring in the 6aS/7b survey area at the time of the survey. The 2022 estimate is the highest estimate in the time series. The flexible survey design and focusing on discreet areas was generally successful and is providing a good template for future survey designs.
  • International Blue Whiting Spawning Stock Survey (IBWSS) Spring 2023

    Marine Institute; Wageningen Marine Research; Institute of Marine Research; Faroe Marine Research Institute; Danish Institute for Fisheries Research; Spanish Institute of Oceanography (Marine Institute, 2023)
    Coordination of the survey was initiated at the meeting of the Working Group on International Pelagic Surveys (WGIPS) in January 2023 and continued by correspondence until the start of the survey. During the survey, effort was refined and adjusted by the survey coordinator (Norway) using real time observations.
  • Celtic Sea Herring Acoustic Survey Cruise Report 2022, 09 - 29 October 2022

    O’Donnell, Ciaran; Mullins, Eugene; Daly, E.; Keogh, Niall; Shine, Andrew (Marine Institute, 2022)
    In the southwest of Ireland and the Celtic Sea (ICES Divisions VIIaS, g and j), herring are an important commercial species to the pelagic and polyvalent fleet. The local fleet is composed of dry hold polyvalent vessels and a smaller number of large purpose built refrigerated seawater vessels (RSW). The stock is composed of both autumn and winter spawning components with the latter dominating. The fishery targets pre-spawning and spawning aggregations in Q3-4. The Irish commercial fishery has historically taken place within 1-20nmi (nautical miles) of the coast. However, since the mid-2000s RSW fleet have actively targeted offshore aggregations migrating from summer feeding in the south Celtic Sea. In VIIj, the fishery is traditionally active from mid-November and is concentrated within several miles of the coast. The VIIaS fishery peaks towards the year end in December, but may be active from mid-October depending on location. In VIIg, along the south coast herring are targeted from October (offshore) to January at a number of known spawning sites and surrounding areas. Overall, the protracted spawning period of the two components extends from October through to February, with annual variation of up to 3 weeks. Spawning occurs in successive waves in a number of well known locations including large scale grounds and small discreet spawning beds. Since 2008 ICES division VIIaS (spawning box C) has been closed to fishing for vessels over 15m to protect first time spawners. For those vessels less than 15m a small allocation of the quota is given to this ‘sentinel’ fishery operating within the closed area. The stock structure and discrimination of herring in this area has been investigated recently. Hatfield et al. (2007) has shown the Celtic Sea stock to be fairly discrete. However, it is known that fish in the eastern Celtic Sea recruit from nursery areas in the Irish Sea, returning to the Celtic Sea as young adults (Brophy et al. 2002; Molloy et al., 1993). The stock identity of VIIj herring is less clear, though there is evidence that they have linkages with VIIb and VIaS (ICES, 1994; Grainger, 1978). Molloy (1968) identified possible linkages between young fish in VIIj and those of the Celtic Sea herring. For the purpose of stock assessment and management divisions VIIaS, VIIg and VIIj have been combined since 1982. For a period in the 1970s and 1980s, larval surveys were conducted for herring in this area. However, since 1989, acoustic surveys have been carried out, and currently are the only tuning indices available for this stock. In the Celtic Sea and VIIj, herring acoustic surveys have been carried out since 1989. Since 2004 the survey has been fixed in October and carried out onboard the RV Celtic Explorer. This year, the survey was conducted onboard the RV Tom Crean. Survey design and geographical coverage have been modified over the time series to adapt to changes in stock size and behaviour. Since 2016, the wider core distribution area has been surveyed by means of two independent surveys and supplemented with small high resolution adaptive surveys focusing on areas of high abundance.
  • Western European Shelf Pelagic Acoustic Survey (WESPAS) 14 June –24 July, 2022. FSS Survey Series: 2022/03

    O'Donnell, Ciaran; O’Malley, Michael B.; Mullins, Eugene; Power, John; judge, Justin; Croot, P. (Marine Institute, 2022)
    The WESPAS survey program is the consolidation of two existing survey programs carried out by FEAS, the Malin Shelf herring acoustic survey, and the boarfish acoustic survey. The Malin Shelf herring acoustic survey has been carried out annually since 2008 and reports on the annual abundance of summer feeding aggregations of herring to the west of Scotland and to the north and west of Ireland from 53°30’N to 58°30’N. The boarfish survey was conducted from 2011 using a chartered fishing vessel and reported the abundance of spawning aggregations of boarfish from 47°N to 57°N. In 2016 both surveys were combined into the WESPAS survey and have been carried out onboard the RV Celtic Explorer over a 42-day period, providing synoptic coverage of shelf waters from 47°30’N northwards to 58°30’N. Age stratified relative stock abundance estimates of boarfish, herring and horse mackerel within the survey area were calculated using acoustic data and biological data from trawl sampling. Stock estimates of boarfish and horse mackerel were submitted to the ICES assessment Working Group for Widely Distributed Stocks (WGWIDE) meeting in August 2022. Herring estimates are submitted to the Herring Assessment Working Group (HAWG) meeting in March every year. Survey performance will be reviewed at the ICES Planning Group meeting for International Pelagic Surveys (WGIPS) meeting in January 2023.
  • International Blue Whiting Spawning Stock Survey (IBWSS) Spring 2022

    Marine Institute; Wageningen Marine Research; Institute of Marine Research; Faroe Marine Research Institute, Marine Scotland Marine Laboratory; Johann Heinrich von Thünen-Institut, Danish Institute for Fisheries Research; Spanish Institute of Oceanography (Marine Institute, 2022)
    Coordination of the survey was initiated at the meeting of the Working Group on International Pelagic Surveys (WGIPS) in January 2022 and continued by correspondence until the start of the survey. During the survey, effort was refined and adjusted by the survey coordinator (Norway) using real time observations. Survey design was based on methods described in ICES Manual for International Pelagic Surveys (ICES, 2015). Overall, weather conditions were exceptional compared to 2021, with calm seas prevailing, providing optimal conditions for acoustic recordings. The entire survey was completed in 15 days, well below 21-day target threshold (Figure 4). Area coverage was considered comprehensive in both core and peripheral areas, with all vessels completing the planned routes, with the exception of the RV Celtic Explorer (Ireland) which returned to port 8 days early.
  • Atlantic Herring in 6aS/7b, Industry Acoustic Survey Cruise Report, December 2021 and January 2022

    O’Malley, M.; Mullins, Eugene; Nolan, Cormac (Marine Institute, 2022)
    An acoustic survey of Atlantic herring Clupea harengus was conducted in ICES areas 6aS/7b in December 2021 and January 2022. The 2021 survey was conducted using five vessels; MFVs Crystal Dawn WD201, Ros Ard SO745, Girl Kate SO427, K-Mar-K SO695 and Rachel D SO976. The 6aS/7b survey design in 2021 focused on 6 core areas with prior knowledge of herring distribution from the monitoring fishery were targeted for surveying. The change in survey design since 2020 was largely based on the results from ICES WKHASS (ICES 2020) and from lessons learned in the previous surveys in this area from 2016-2019. This design resulted in a much reduced survey area compared to previous years, but with better coverage of most of the important inshore bays where the monitoring fishery takes place. The survey design objective remained the same; to capture the distribution of winter spawning herring in the 6aS/7b area, but this design was not expected to achieve overall stock containment. The timing of surveys in the core areas was flexible from the outset by design. The greater flexibility allows for a targeted spatial and temporal approach which avoided the inevitable poor weather that can happen in this area during this time of the year and which lead to reduced survey effort in some previous years. Using smaller vessels allowed surveys to be conducted in shallow inshore areas where herring are known to aggregate during this time of the year. This survey is the sixth consecutive annual acoustic survey for pre-spawning herring in this area at this time of the year. A pole-mounted system with a combi 38 kHz (split) 200 kHz (single) transducer was used successfully for the survey on small vessels (<18m) in 2021. Herring were again distributed inshore in shallow areas, and the improved survey design and use of small vessels for the survey resulted in a good measure of uncertainty (CV =0.23). The stock was not overall contained in 2021, particularly in the Donegal Bay area (Malin Beg, etc.) and more effort is required to target surveys earlier and later than December and January when herring tend to show up in these areas in difficult to predict patterns. Very strong herring marks were evident in Lough Foyle and Lough Swilly in the channel in marks that extended for many miles in some cases. This was in areas where smaller boats in the fishery were concentrating effort. Herring had left the Swilly by mid-December and the Foyle by mid-January. There was also a series of strong herring marks in Bruckless Bay, Fintra Bay (SE of Inishduff) and Inver Bay in discreet areas. The monitoring fishery was being conducted on smaller boats in the same areas and close to the same time as the survey and biological samples from some of these vessels were used. There was a fairly tight distribution of length classes in all hauls, with most hauls dominated by larger (> 22 cm) mature fish. The 2- and 3-wr age class of herring accounted for 74% of the overall numbers in 2021. The total stock biomass (TSB) estimate of 35,944 tonnes is considered to be a minimum estimate of herring in the 6aS/7b survey area at the time of the survey. The flexible survey design and focusing on discreet areas was generally successful and is providing a good template for future survey designs.
  • Celtic Sea Herring Acoustic Survey Cruise Report 2021, 08 - 28 October 2021

    O'Donnell, Ciaran; Mullins, Eugene; Daly, E.; Keogh, Niall; Collins, John (Marine Institute, 2021)
    In the southwest of Ireland and the Celtic Sea (ICES Divisions VIIaS, g & j), herring are an important commercial species to the pelagic and polyvalent fleet. For a period in the 1970s and1980s, larval surveys were conducted for herring in this area. However, since 1989, acoustic surveys have been carried out, and currently are the only tuning indices available for this stock. In the Celtic Sea and VIIj, herring acoustic surveys have been carried out since 1989. Since 2004 the survey has been fixed in October and carried out onboard the RV Celtic Explorer. The geographical confines of the annual 21 day survey have been modified in recent years to include areas to the south of the main winter spawning grounds in an effort to identify the whereabouts of winter spawning fish before the annual inshore spawning migration. Spatial resolution of acoustic transects has been increased over the entire south coast survey area. The acoustic component of the survey has been further complemented since 2004 by detailed hydrographic, marine mammal and seabird surveys. Survey design and geographical coverage have been modified over the time series to adapt to changes in stock size and behaviour. Since 2016, the wider core distribution area has been surveyed by means of two independent surveys and supplemented with small high resolution adaptive surveys focusing on areas of high abundance.
  • Western European Shelf Pelagic Acoustic Survey (WESPAS), 09 June –20 July, 2021

    O’Donnell, Ciaran; O’Malley, M.; Mullins, E; Connaughton, P.; Keogh, Niall; judge, Justin; Croot, P. (Marine Institute, 2021)
    The WESPAS survey program is the consolidation of two existing survey programs carried out by FEAS, the Malin Shelf herring acoustic survey, and the boarfish acoustic survey. The Malin Shelf herring acoustic survey has been carried out annually since 2008 and reports on the annual abundance of summer feeding aggregations of herring to the west of Scotland and to the north and west of Ireland from 53°30’N to 58°30’N. The boarfish survey was conducted from 2011 using a chartered fishing vessel and reported the abundance of spawning aggregations of boarfish from 47°N to 57°N. In 2016 both surveys were combined into the WESPAS survey and have been carried out onboard the RV Celtic Explorer over a 42-day period, providing synoptic coverage of shelf waters from 47°30’N northwards to 58°30’N. Age stratified relative stock abundance estimates of boarfish, herring and horse mackerel within the survey area were calculated using acoustic data and biological data from trawl sampling. Stock estimates of boarfish and horse mackerel were submitted to the ICES assessment Working Group for Widely Distributed Stocks (WGWIDE) meeting in August 2021. Herring estimates are submitted to the Herring Assessment Working Group (HAWG) meeting in March every year. Survey performance will be reviewed at the ICES Planning Group meeting for International Pelagic Surveys (WGIPS) meeting in January 2022.
  • Atlantic Herring in 6aS/7b, Industry Acoustic Survey Cruise Report, November-December 2020 and January 2021.

    O'Malley, M.; Mullins, Eugene; Nolan, Cormac (Marine Institute, 2021)
    An acoustic survey of Atlantic herring Clupea harengus was conducted in ICES areas 6aS/7b in November-December 2020 and January 2021. The 2020 survey was conducted using five vessels; MFVs Crystal Dawn WD201, Ros Ard SO745, Johnny G S653, Abigail S SO354, and St. Catherine D299. The 6aS/7b survey design changed in 2020 compared with previous years in that only 6 core areas with prior knowledge of herring distribution from the monitoring fishery were targeted for surveying. This was largely based on the results from ICES WKHASS (ICES 2020) and from lessons learned in the previous surveys in this area from 2016-2019. This design resulted in a much reduced survey area compared to previous years, but with better coverage of most of the important inshore bays where the monitoring fishery takes place. The survey design objective remained the same; to capture the distribution of winter spawning herring in the 6aS/7b area, but this design was not expected to achieve overall stock containment. The timing of surveys in the core areas was flexible from the outset by design. It was decided that greater flexibility would allow for a targeted spatial and temporal approach which avoided the inevitable poor weather that can happen in this area during this time of the year and which lead to reduced survey effort in previous years. Using smaller vessels allowed surveys to be conducted in shallow inshore areas where herring are known to aggregate during this time of the year. This survey is the fifth consecutive annual acoustic survey for herring in this area at this time of the year. A pole-mounted system with a combi 38 kHz (split) 200 kHz (single) transducer was used successfully for the survey on small vessels (<18m) in 2020. Herring were again distributed inshore in shallow areas, and the improved survey design and use of small vessels for the survey resulted in a good measure of uncertainty (CV). The stock was not overall contained in 2020, particularly in the Donegal Bay area (Bruckless, Inver Bays, etc.) and more effort is required to target survey effort later in December and January when herring appear to show up in these areas in greater numbers. The COVID pandemic affected the ability to conduct surveys in late December. Very strong herring marks were evident in Lough Foyle and Lough Swilly in the channel in marks that extended for many miles. This was in areas where smaller boats in the fishery were concentrating effort. There was also a series of herring marks in Bruckless Bay, Fintra Bay and Inver Bay in discreet areas. There were a few small herring marks in the Achill strata. The monitoring fishery was being conducted on smaller boats in the same areas and close to the same time as the survey and biological samples from some of these vessels were used. There was a wide distribution of length classes in all hauls, with most hauls dominated by larger (> 22 cm) mature fish. The 2- and 3-wr age class of herring accounted for 54% of the overall numbers in 2020. The total stock biomass (TSB) estimate of 45,046 tonnes is considered to be a minimum estimate of herring in the 6aS/7b survey area at the time of the survey. The flexible survey design and focusing on discreet areas was generally successful and should provide a template for future survey designs.
  • International Blue Whiting Spawning Stock Survey (IBWSS) Spring 2021

    Marine Institute; Wageningen Marine Research; PINRO; Faroe Marine Research Institute; Danish Institute for Fisheries Research; Spanish Institute of Oceanography; Institute of Marine Research (Marine Institute, 2021)
    Coordination of the survey was initiated at the meeting of the Working Group on International Pelagic Surveys (WGIPS) in January 2021 and continued by correspondence until the start of the survey. During the survey effort was refined and adjusted by the survey coordinator (Norway) using real time observations. The survey design was based on methods described in ICES Manual for International Pelagic Surveys (ICES, 2015). Weather conditions were regarded as exceptionally poor and all vessels experienced multiple days of downtime, with the exception of the Spanish vessel working in the Porcupine Seabight. This considered, the stock was covered comprehensively and contained within the survey area. The entire survey was completed in 19 days, below 21-day target threshold.
  • Celtic Sea Herring Acoustic Survey Cruise Report 2020, 04 - 24 October, 2020

    O’Donnell, C.; Mullins, E.; Lyons, K.; Connaughton, P.; Perez Tadeo, M. (Marine Institute, 2020)
    In the southwest of Ireland and the Celtic Sea (ICES Divisions VIIaS, g & j), herring are an important commercial species to the pelagic and polyvalent fleet. For a period in the 1970s and1980s, larval surveys were conducted for herring in this area. However, since 1989, acoustic surveys have been carried out, and currently are the only tuning indices available for this stock. In the Celtic Sea and VIIj, herring acoustic surveys have been carried out since 1989. Since 2004 the survey has been fixed in October and carried out onboard the RV Celtic Explorer. The geographical confines of the annual 21 day survey have been modified in recent years to include areas to the south of the main winter spawning grounds in an effort to identify the whereabouts of winter spawning fish before the annual inshore spawning migration. Spatial resolution of acoustic transects has been increased over the entire south coast survey area. The acoustic component of the survey has been further complemented since 2004 by detailed hydrographic, marine mammal and seabird surveys.
  • Western European Shelf Pelagic Acoustic Survey (WESPAS), 03 June – 12 July, 2020

    O'Donnell, Ciaran; O’Malley, M.; Smith, T.; O’Brien, S.; Mullins, E.; Connaughton, P.; Perez Tadeo, M.; Barile, C. (Marine Institute, 2020)
    The WESPAS survey program is the consolidation of two existing survey programs carried out by FEAS, the Malin Shelf herring acoustic survey, and the boarfish acoustic survey. The Malin Shelf herring acoustic survey has been carried out annually since 2008 and reports on the annual abundance of summer feeding aggregations of herring to the west of Scotland and the north and west of Ireland from 54°N to 58°30’N. The boarfish survey was conducted from 2011 using a chartered fishing vessel and reported the abundance of spawning aggregations of boarfish from 47°N to 57°N. In 2016 both surveys were combined into the WESPAS survey and have been carried out onboard the RV Celtic Explorer over a 42-day period, providing synoptic coverage of shelf waters from 47°30’N northwards to 58°30’N. Age stratified relative stock abundance estimates of boarfish, herring and horse mackerel within the survey area were calculated using acoustic data and biological data from trawl sampling. Stock estimates of boarfish and horse mackerel were submitted to the ICES assessment Working Group for Widely Distributed Stocks (WGWIDE) meeting in August 2020. Herring estimates are submitted to the Herring Assessment Working Group (HAWG) meeting in March every year. Survey performance will be reviewed at the ICES Planning Group meeting for International Pelagic Surveys (WGIPS) meeting in January 2021.
  • Atlantic Herring in 6aS/7b, Industry Acoustic Survey Cruise Report

    O’Malley, M.; Smith, T.; Mullins, E. (Marine Institute, 2020)
    An acoustic survey of Atlantic herring Clupea harengus was conducted in ICES areas 6aS/7b in Dec 2019 using the research vessel RV Celtic Voyager and the fishing vessel MFV Ros Ard SO745. This survey is the fourth in a time series that is hoped will be developed into a long-term index of spawning/pre-spawning herring in 6aS/7b. The survey design is based on the predicted distribution of this winter spawning herring in this area. Poor weather negatively impacted the survey in 2019, resulting in fewer transect miles completed and fewer strata areas covered than planned. In total, approximately 600nmi of cruise track was completed using 96 transects. This resulted in a total area coverage of approximately 606 nmi², a significant reduction compared to recent years. Parallel transect spacing was set at 3.5nmi for the Donegal Bay strata. Tightly spaced zig-zag transects were used in a relatively small area in Lough Swilly. A Simrad ES-120 7CD (120 kHz) split-beam echosounder was used to collect acoustic raw data. The transducer was mounted on a towed body from the Celtic Voyager in Donegal Bay and was pole mounted from the Ros Ard in Lough Swilly. Very strong herring marks were evident in Lough Swilly in deepest part of the channel. The herring marks continued for many miles in the upper Swilly, an area where boats in the monitoring fishery had also concentrated effort. There were some herring marks in discreet areas around Drumanoo Head, Bruckless Bay and Inver Bay in the Donegal Bay Strata. Biological samples from the monitoring fishery of herring were used to augment the samples from the survey. Herring samples were taken from boats fishing in Lough Swilly and Inver Bay as close spatially and temporally as possible to the survey in these areas. Herring were dominated overall by 1- and 2-wr fish, (52% of the overall numbers) followed by relatively strong 3- and 5-wr cohorts. The total stock biomass (TSB) estimate of herring for the combined 6aS/7b area was 25,289 tonnes (Lough Swilly = 19,697 tonnes, Donegal Bay = 5,591 tonnes). This is considered to be a minimum estimate of herring in the 6aS/7b survey area at the time of the survey, and a significant decrease on the previous 3 years surveys. The reduction in the survey area completed as a consequence of the poor weather resulted in the survey not containing the stock in 2019. However, the overall CV estimate on biomass and abundance for the survey area completed is low (~0.17) in 2019. This is driven by the improved survey design in Lough Swilly, with reduced transect spacing and increased transect miles in this strata. The CV for the Donegal Bay strata is relatively high (0.63), this is mostly caused by the over-reliance on a few acoustic marks of herring in Bruckless and Inver Bays in particular and many transects with little or no herring marks. The survey in 2019 had to be altered due to weather, requiring a change in design and approach. However, the template of focusing on discreet areas was generally successful and may provide a template for future designs, particularly when reduced effort is necessary during poor weather or resource limits.
  • Celtic Sea Herring Acoustic Survey Cruise Report 2019, 09 - 29 October, 2019

    O'Donnell, C.; Mullins, E.; Lynch, D.; Lyons, K.; Connaughton, P.; Power, J. (Marine Institute, 2019)
    In the southwest of Ireland and the Celtic Sea (ICES Divisions VIIaS, g & j), herring are an important commercial species to the pelagic and polyvalent fleet. For a period in the 1970s and1980s, larval surveys were conducted for herring in this area. However, since 1989, acoustic surveys have been carried out, and currently are the only tuning indices available for this stock. In the Celtic Sea and VIIj, herring acoustic surveys have been carried out since 1989. Since 2004 the survey has been fixed in October and carried out onboard the RV Celtic Explorer. The geographical confines of the annual 21 day survey have been modified in recent years to include areas to the south of the main winter spawning grounds in an effort to identify the whereabouts of winter spawning fish before the annual inshore spawning migration. Spatial resolution of acoustic transects has been increased over the entire south coast survey area. The acoustic component of the survey has been further complemented since 2004 by detailed hydrographic, marine mammal and seabird surveys.
  • Western European Shelf Pelagic Acoustic Survey (WESPAS) 13 June - 24 July, 2019

    O’Donnell, C.; O’Malley, M.; Lynch, D.; Mullins, E.; Connaughton, P.; Power, J.; Long, A.; Croot, P. (Marine Institute, 2020)
    The WESPAS survey program is the consolidation of two existing survey programs carried out by FEAS. The Malin Shelf herring acoustic survey has been carried out annually since 2008 and reports on the annual abundance of summer feeding aggregations of herring to the west of Scotland and to the north and west of Ireland from 54°N to 58°30’N. The boarfish survey was carried out from 2011 using a chartered fishing vessel and reports on the abundance of spawning aggregations of boarfish from 47°N to 57°N. In 2016 both surveys were combined and carried out onboard the RV Celtic Explorer over a 42 day period providing synoptic coverage of shelf waters from 47°N northwards to 58°30’N.
  • International Blue Whiting Spawning Stock Survey (IBWSS) Spring 2019

    Marine Institute; Wageningen Marine Research; Institute of Marine Research; PINRO; Faroe Marine Research Institute; Marine Scotland Marine Laboratory; Johann Heinrich von Thünen-Institut; Danish Institute for Fisheries Research; Spanish Institute of Oceanography (Marine Institute, 2019)
    Coordination of the survey was initiated at the meeting of the Working Group on International Pelagic Surveys (WGIPS) in January 2019 and continued by correspondence until the start of the survey. During the survey effort was refined and adjusted by the survey coordinator (Norway) using real time observations. The survey design was based on methods described in ICES Manual for International Pelagic Surveys (ICES, 2015). Overall weather conditions were mixed with periods of poor and good weather. All vessels experienced some downtime due to poor weather conditions. The entire survey was completed in 26 days, above the 21-day target threshold. However, the survey start was delayed by almost one week compared to 2018 and included additional effort by the Spanish survey in the Porcupine Sea bight.
  • Blue Whiting Acoustic Survey cruise report, March 20- April 06, 2018

    O'Donnell, D.; Johnston, G.; Mullins, E.; Keogh, N.; Power, J. (O'Donnell, D., Johnston, G., Mullins, E., Keogh, N. and Power, J. (2018). Blue Whiting Acoustic Survey cruise report, March 20- April 06, 2018. FSS Survey Series: 2018/01. Marine Institute, 2018)
    Acoustic surveys targeting blue whiting (Micromesistius poutassou) spawning and post spawning aggregations in the north east Atlantic have been carried out by the Institute of Marine Research (IMR) Norway since the early 1970s. The 2018 survey was part of an international collaborative survey using the vessels RV Celtic Explorer (Ireland), RV Tridens (Netherlands), FV Kings Bay (Norway) and the RV Magnus Heinason (Faroes). The total combined area coverage extended from the Faroe Islands in the north (62° N) to south of Ireland (51° N), with east -west extension from 1°-18° W. To the south of 51°N the Spanish research vessel the RV Miguel Oliver conducted a survey, complimentary to, but separate to the IBWSS survey, as part of their annual PELACUS survey program. International survey participants met shortly after the survey to present data and produce a combined relative abundance stock estimate and report. The combined survey report is presented annually at the WGIPS meeting held in January. The information presented here relates specifically to the Irish survey unless otherwise stated.
  • Atlantic Herring and Horse Mackerel in 6aS/7b; Industry Acoustic Survey Cruise Report

    O'Malley, M.; Blaszkowski, M.; White, Emma; O'Brien, S.; Mullins, E. (Marine Institute, 2019)
    An acoustic survey of Atlantic herring Clupea harengus and horse mackerel Trachurus trachurus was conducted in ICES areas 6aS/7b in Nov 2018 using the pair trawl vessels MFV Eilean Croine S238 and MFV Sparkling Star D437. This survey is the third in a time series that is hoped will be developed into a long-term index of spawning/pre-spawning herring and horse mackerel in 6aS/7b, for use in stock assessments in the future. The survey design was based on the predicted distribution of herring and horse mackerel in this area during this time. In total 1,400nmi of cruise track was completed using 37 transects and related to a total area coverage of approximately 5,600 nmi². Parallel transect spacing was set at 7.5nmi for the wider area strata, and 3.5nmi for Donegal Bay and Achill strata. Coverage extended from inshore coastal areas to the 200 m contour in the west and north where possible. A survey was carried out in Lough Swilly using a zig-zag design. A Simrad ES-38B (38 kHz) split-beam transducer mounted on a towed body was used to collect acoustic raw data. Very strong herring marks were evident in Lough Swilly, an area where boats in the monitoring fishery were concentrating effort. There were a few herring marks in discreet areas around Glen Head, Bruckless Bay, Inishmurray and Inishbofin. A total of four commercial fishing hauls on horse mackerel were completed during the survey. Biological samples from the monitoring fishery of herring were used to augment the samples from the survey. Herring samples were taken from boats fishing in Lough Swilly and Bruckless Bay as close spatially and temporally as possible to the survey in these areas. Herring were dominated overall by 4-wr fish, 29% of the overall numbers. Horse mackerel were distributed throughout the survey area, but particularly throughout the area to the north and west of the Stags of Broadhaven. Horse mackerel length distribution was dominated by a mode at 25-26cm. This corresponded to a dominance of 4-wr fish (~89%) in all of the samples. The total stock biomass (TSB) estimate of herring for the combined 6aS/7b area was 50,145 tonnes (Lough Swilly = 32,372 tonnes, Donegal Bay = 9,517 tonnes, NW area = 7,710 tonnes and the remaining Achill strata = 545 tonnes). This is considered to be a minimum estimate of herring in the 6aS/7b survey area at the time of the survey. The TSB estimate of horse mackerel for the total surveyed area in 6aS/7b area was 57,162 tonnes, considered to be a minimum estimate of horse mackerel in the 6aS/7b survey area at the time of the survey. The CV estimates on biomass and abundance are high (~0.51 for herring and ~ 0.36 for horse mackerel) for the survey in 2018. For herring, this is mostly caused by the over-reliance on a few acoustic marks of herring in Lough Swilly and Bruckless Bay in particular. Horse mackerel are a widely distributed stock, therefore the stock was not contained by this survey.

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