Anglerfish in Area IV (North Sea), VI (West of Scotland and Rockall), Demersal gillnet

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1 Anglerfish in Area IV (North Sea), VI (West of Scotland and Rockall), Demersal gillnet Content last updated 22nd Feb 2018 Stock: Anglerfish in Area IV (North Sea), VI (West of Scotland and Rockall), Demersal gillnet Management: EU Anglerfish in Area IV (North Sea), VI (West of Scotland and Rockall), Demersal gillnet Overview Two species of anglerfish (Lophius piscatorius, and L. budegassa), also known as monkfish, are caught in European Seas. Lophius piscatorius inhabits the Northeastern Atlantic from Norway (Barents Sea) to the Straits of Gibraltar (and including the Mediterranean and the Black Sea). Lophius budegassa has a more southerly distribution from the British Isles and Ireland to Senegal. Anglerfish are found on sandy and muddy sediments in depths of up to 1000 m. They ambush fish or other prey attracted to a modified dorsal fin ray acting as a lure. Tagging studies have shown that the species can undertake extensive migrations, from Shetland to Faroe and Iceland, for example. The two European anglerfish species are usually caught together where the ranges overlap, and historically the two species have often not been recorded separately in the landing statistics. Until the mid-1980s, anglerfish were taken mainly as bycatch in bottom-trawl groundfish fisheries. Restrictive TACs for other species in Division VIa led to increased fishing pressure on anglerfish in that area, where they are now caught in a targeted anglerfish fishery and as bycatch in other demersal fisheries. Anglerfish mature at large size, resulting in a large proportion of the catch consisting of immature fish. The fishery has expanded into deeper waters since the mid-nineties, into areas that are believed to have been a refuge for adult anglerfish. This fishery thus increases the vulnerability of the stock to overexploitation. Stock Status less risk more risk Anglerfish in Sub area IV and VI has been scored moderate risk. This is because anglerfish has a relatively high vulnerability score and the stock size indicator used as a proxy for stock status has increase and is above the long term average. Management less risk more risk The management of anglerfish in Sub area IV and VI has been scored a moderate risk. This is because an assessment of the state of the stock and subsequent advice is based on a data-limited approach using survey-based indices of abundance. There is concern over the use of a combined assessment and TAC for the two species which carries the risk of one of the species being overexploited. Bycatch less risk more risk The bycatch in the gill net fishery has been scored a moderate risk. This is because demersal gillnets catching anglerfish risk the incidental capture of marine mammals and sharks. Ghost fishing, where lost gear continues to fish is a problem in the gillnet fishery. This is because the nets are made up of synthetic monofilament which does not break down and continues to fish for a long period of time. Habitat less risk more risk The habitat risk of this fishery has been scored a low risk. This is because habitat damage tends to be low as the gear is static and therefore has limited impact on the seafloor when compared to a towed gear. Penetration and abrasion effects are limited to shooting and hauling the gear. There is also potential for the gear to become snagged on biogenic features. Outlook Current risk status Outlook Reason Stock Moderate Stable Although anglerfish are vulnerable to overexploitation the biomass index used to assess the state of the stock has fluctuated without trend since 2005, increasing in the most recent years giving an indication that it is likely to remain stable. Management Moderate Stable There is a risk of the use of a combined TAC for the two species which could lead to one of the species being overexploited. However, the CFP is going through reform and there is some uncertainty on how this will impact fisheries management in the North Sea and West of Scotland. Bycatch Moderate Stable Technical and spatial management measures are under development and will likely reduce the risk further. Habitat Low Stable Technical and spatial management measures are under development and will likely reduce the risk further.

2 Type Current Risk Status Outlook Reason Stock Moderate Stable/ improving A biomass index seems to suggest that the stock is increasing. Management Moderate Stable/ improving The harvest strategy for monkfish in the North Sea and West of Scotland will likely improve going forward as this stock has been put into a fisheries improvement project as part of Project UK. Bycatch Moderate Stable Technical and spatial management measures are under development and will likely reduce the risk further. Habitat Low Stable Technical and spatial management measures are under development and will likely reduce the risk further.

3 Stock Status Details less risk more risk Time-trends The two anglerfish species are assessed together using a data limited method. The Scottish and Irish anglerfish and megrim industry/science surveys in Division IVa and Subarea VI indicate that the average biomass has been more than 60% higher in the last two years ( ) than the average of the three previous years ( ). However, there is no trend in biomass over the full time-series of survey data. Landings increased to a peak in the mid 1990s then declined to just below the average for the time series. Figure 1. Anglerfish in subareas 4 and 6 and Division 3.a. Summary of the stock assessment. Top: Official and ICES landings and discards (thousand tonnes). Bottom left: Relative harvest rate (total catch/stock size indicator; normalized to the average harvest rate). Bottom right: Stock biomass (thousands tonnes) from SCO-IV-VI-AMISS-Q2. The dashed horizontal lines indicate the average of the most recent two years and the previous three years. The shaded area represents the 95% confidence interval (ICES 2017). Stock structure and recruitment The boundaries for this stock are not based on biological or genetic criteria and more research is being carried out to determine stock structures. Both microsatellite DNA analysis and particle tracking studies carried out as part of EC 98/096 (Anon, 2001) also suggested that anglerfish from Kattegat, Skagerrak and further south (Subarea VII) could also be part of the same stock. During spawning, anglerfish extrude eggs in a buoyant, gelatinous ribbon that can measure more than 10 m in length (Quincoces, 2002). This results in a highly clumped distribution of eggs and newly emerged larvae. Subsequent recruitment is thought to be strongly driven by environmental conditions. Data gaps and research priorities Improved sampling of the length composition of catches and more accurate estimates of growth parameters are needed to facilitate the development of an analytical assessment. Determination of fish age from calcified structures otoliths (ear bones) and illicia (the dorsal fin ray acting as a fishing rod) has proved difficult and ICES has found poor agreement between methods or readers using the same method. The ages from either method have also not been validated as representing true ages. Insufficient reliable estimates of discards are available for inclusion in the assessment. Discarding is known to be partly dependent on market conditions and quota restrictions as well as an EU minimum weight landing restriction of 500 g for marketing purposes (EC Regulation 2406/96). Efforts should be made to obtain reliable estimates of total catches (landings and discards combined) in order to improve the assessment. Anon The distribution and biology of anglerfish and megrim in waters to the west of Scotland. EC Study Contract 98/096 Final Report August ICES Advice basis. In Report of the ICES Advisory Committee, ICES Advice 2014, Book 5, Section Quincoces, I Crecimiento y reproducción de las especies Lophius budegassa Spinola1807, y Lophius piscatorius Linneo 1758, del Golfo de Vizcaya. PhD Thesis. Basque Country Univer-sity. 276 pp.

4 Management Details less risk more risk TAC Information Catch 2016 (t) Advised Catch 2017 (t) Agreed TAC 2017 (t) Advised Catch 2018 (t) Stock harvest strategy Anglerfish in the northern North Sea and West of Scotland is assessed annually using a data-limited approach to estimate trends in landings and biomass. The stock assessment is based on a time-series of international commercial fishery landings as well as trends in biomass derived from the catch rates of standardised trawl surveys involving commercial vessels as part of an industry-science collaboration. Reference points have not been defined for either species, and therefore it is difficult to infer the status of the stock with confidence (ICES 2014). Discarding is monitored by at-sea observer schemes, and landings are monitored through EU logbooks and sales slips as required by Council Regulation (EC) No 1224/2009. Anglerfish in Sub area IV and VI is managed under the EU Common Fisheries Policy (CFP) primarily through annual Total Allowable Catches (TACs) which are set for both anglerfish species combined. There is concern over the use of a combined TAC for the two species of anglerfish which carries the risk of one of the species being overexploited. Underreporting of total landings is known to have been a significant problem in the past. Less restrictive quotas have reduced the incentive to misreport and the introduction of the registration of buyers and sellers scheme in Scotland and Ireland in 2006 has made it more difficult to make unreported landings. International effort trends for the main gears in ICES Subarea IV and Division VIa, as collated and presented by the STECF effort group, show effort reductions in largermeshed trawls, the main gear catching anglerfish, in both areas, particularly in ICES Division VIa. Reductions in fishing effort associated with the long term cod management plan (Regulation (EC)1342/2008), and the sole and plaice long-term management plan (Council Regulation (EC) No. 676/2007), may have influenced anglerfish catches and fishing mortality. Surveillance and enforcement Fisheries on anglerfish in Sub area IV and VI are carried out by seven countries, and surveillance activities to record compliance with national and international fishery control measures are primarily the responsibility of the competent fishery inspection authorities in each country. In addition, the European Fisheries Control Agency (EFCA), established in 2005, organises operational coordination of fisheries control and inspection activities by the Member States as well as cooperation with third countries and other Regional Fishery Management Organisations. The requirements for surveillance and sanctions for infringements are laid down in the EU Control Regulation (EC) No 1224/2009. Surveillance activities on fisheries for anglerfish in Sub area IV and VI include the use of vessel monitoring systems (VMS) on vessels over 12m overall length, an electronic reporting system (ERS), and a vessel detection system (VDS). Surveillance may also include direct observation by patrol vessels and/or aerial patrols, inspections of vessels, gear, catches at sea and on shore, and verification of EU logbook data against sales documents. The EU Control Regulation specifies that Member States should set up electronic databases containing the inspection and surveillance reports of their officials as well as records of infringements. EFCA. [ [Date accessed: 23-Dec-15] ICES Report of the Working Group on Celtic Seas Ecoregion (WGCSE), May, Copenhagen, Denmark. ICES CM 2014/ACOM:12. 5 pp.

5 Bycatch Details less risk more risk Targeting and behaviour A demersal gillnet and entangling nets consist of strings of single, double and triple netting walls, comprising a series of panels joined together, which is set on the seabed using anchors to hold the net in place. The anglerfish fishery typically uses nets with large mesh size of around 220mm and above above. Fish become enmeshed by their gills, fins and teeth, or become otherwise tangled in the netting. The soak times, total length of netting and other aspects of net rigging are varied according to habitat and species targeted. Mesh size is tailored to suit the target species and to conform with any regulations that are in place. Evidence of bycatch risks Gillnets and tangle nets are likely to be non-selective for anglerfish, because the shape of the fish means that fish of a wide size range may be tangled by their teeth and fins, especially in nets set as tangle nets. Discards are known to take place but are around 2 % on average of catch over period for the top 10 species. Cod and Saithe have the highest discard rate in divisions IV and VI respectively. According to Agreement on the Conservation of Small Cetaceans in the Baltic, North East Atlantic, Irish and North Seas (ACSOBANS) accidental entanglement in fishing gear is generally considered the most serious threat to cetacean populations. Due to their inshore distribution and benthic feeding habits, harbour porpoise populations are especially vulnerable to bycatch in bottom-set gillnets. Most netting for anglerfish however takes place in deeper offshore waters. Mitigation measures EU Council Regulation 812/2004 requires the use of an acoustic deterrent device, known as a pinger, to reduce the level of dolphin and porpoise (cetacean) by-catch, for specified gears, areas and time periods. For example, in the North Sea, such devices are required from 1 August to 31 October for any bottom-set gillnet or entangling net, or combination of these nets, the total length of which does not exceed 400 metres, and where the mesh size is less than 220mm. For any such nets with mesh size of 220mm or greater, pingers must be used all year. Although there is no minimum landing size for anglerfish, there is an EU minimum weight of 500 g for marketing purposes (EC Regulation 2406/96). Offshore gillnet fisheries carried out by flag-vessels targeting anglerfish (previously considered to be responsible for a significant amount of ghost fishing and subsequent discarding) are now considered to be much reduced. This is expected to have led to improved data on total catches of anglerfish. ASCOBANS [ [Date accessed: 15-Jan-16] Anon Discard Atlas of the North Sea Fisheries, August 2014, 80 pp.

6 Habitat Details less risk more risk Gear effects, targeting and behaviour Anglerfish are targeted or taken as a bycatch in gillnets and tangle nets anchored at the seabed. The anchoring of these nets has minimal impact on the sea floor but there is potential for nets that are lost through bad weather, interaction with the seabed or other gears, to continue to ghost fish for a long time with negative impact on marine life. Research suggests this could be for up to a year before the nets deteriorate and act as a substratum for many colonising plants and animals, increasing net visibility and providing a complex habitat that is attractive to many organisms (Brown and Macfadyen, 2007, Baeta et. al. 2009). Mitigation measures Under the Marine Strategy Framework Directive (MSFD) from the European Union (Council Directive 56/2008), Member States have commited to aim towards good environmental status (GES) for the seabed habitats by The Convention for the Protection of the Marine Envrionment of the North-East Atlantic (the OSPAR Convention ), which was signed up to by 15 nations plus the European Union, is developing a coherent network of Marine Protected Areas to protect vulnerable marine habiats in the North-East Atlantic. The development of offshore Special Areas of Conservation under the European Habitats Directive (Council Directive 43/1992) contributes to this. The rate of permanent net loss are often low and generally below one percent (Brown and Macfadyen, 2007) this is mainly due to the level of self-recovery of nets with the use of global positioning systems and the considerable effort fisheries will go to to recover gear given the cost of replacement, especially for the under 10 m fishing fleet. Baeta. F., Costa. M. J., Cabral. H., 2009, Trammel nets ghost fishing off the Portuguese central coast. Fisheries Research Brown, J., Macfadyen, G., Ghost fishing in European waters: impacts and management responses. Mar. Policy 31, All content 2018 Seafish. Origin Way, Europarc, Grimsby, DN37 9TZ. This page created on 3rd September 2018 at 06:33pm.