HOME  BACKGROUND  WHO'S INVOLVED?  LIBRARY  NEW UK LIST REPORTING    OLD PLANS  HELP   SEARCH

These plans are from the original UKBAP Tranches 1 and 2 (1995-1999)
For up-to-date information please visit The Biodiversity Action Reporting System (BARS)

Plans | Species | Fish | Grouped plan for deep-water fish

Grouped Species Action Plan

Grouped plan for deep-water fish 

Current status

For this action plan, deep-water fishes are considered to be those species that live at depths greater than 400 m. They comprise three main categories: mesopelagic, bathypelagic and benthopelagic. Mesopelagic and bathypelagic species are true pelagic fish, generally of small adult size and unlikely to be commercially exploited. Mesopelagic fishes, such as lantern fishes (Myctophidae) and cyclothonids (Gonostomatidae) live beneath the photic zone to approximately 1000 m depth. Many species migrate toward the surface at night and descend to depth during the day thereby forming a trophic link between surface waters and the benthopelagic fishes. Bathypelagic fishes live below 1000 m and are usually highly adapted to life in a food-poor environment. Examples are the deep-water angler fishes (eg Ceratidae) and the gulper eels (Eurypharyngidae). The benthopelagic species live on or close to the bottom. Among the more important commercially exploited species are the roundnose grenadier Coryphaenoides rupestris, blue ling Molva dypterygia and orange roughy Hoplostethus atlanticus, but the ubiquitous shelf sea monkfish or anglerfish (Lophius piscatorius and L. budegassa) are also taken with the deep-water species.
The bottom trawl fisheries of the Atlantic slope can be divided into three broad types: an upper slope (c. 400-800 m) fishery targeting blue ling and monkfish and prosecuted mainly by French and UK vessels; a mid-slope fishery (800-1200 m) by mainly French vessels targeting blue ling and roundnose grenadier; a deep French fishery (1200-1700 m) targeting orange roughy.
The longline fisheries on the Atlantic slope are essentially confined to Spanish and UK registered vessels landing in Spain, and Norway. The main target species for the Spanish market is hake Merluccius merluccius, with deep-water sharks as a by-catch. Depending on prices, sharks can sometimes be the target species. The Norwegian fishery is centred on blue ling, ling Molva molva and tusk Brosme brosme.
Bottom gillnets have been used by Spanish vessels to target monkfish Lophius spp in international waters to the west of the Rockall Plateau. A by-catch is the deep-water crab Chaceon (Geryon) affinis.
The bottom trawl fishery west of Shetland has two main components. The fishery on the upper slope (c. 400-800 m) targets blue ling and monkfish with a by-catch of species such as redfish Sebastes spp. Lower down the slope is a relatively new fishery for Greenland halibut Reinhardtius hippoglossoides, mainly undertaken by Norwegian and in recent years Scottish vessels, in which redfish, roughhead grenadier Macrourus berglax and the Arctic skate Raja hyperborea form a by-catch. Little is known of the stock structure for any of these species.
There are also seasonal fisheries on spawning aggregations of argentine or greater silver smelt Argentina silus and blue whiting Micromesistius poutassou across the upper slope from Spain north to Faeroe-Shetland. The fishery for blue whiting takes place to the west of the British Isles and is mainly carried out by Norway, but Russia, the UK and Netherlands also have significant catches. However, neither of these species nor the angler fishes are cause for concern compared to the other, true deep-water species named here. Consequently, they are not included in this action plan.
Much of the available information on the deep-water fish and their fisheries, has been assembled by the International Council for the Exploration of the Sea (ICES) Study Group on the Biology and Assessment of Deep-Sea Fisheries Resources. The group does not cover monkfish, redfish Sebastes spp or Greenland halibut as these are assessed by other ICES Working Groups.
The majority of deep-water species are covered by the international definition ofhighly migratory and straddling stocks; ie they range across one or more international boundaries. Responsibility for their management falls to the North East Atlantic Fisheries Commission (NEAFC). For some years past, NEAFC has requested the ICES Study Group to update descriptions of deep-water fisheries in waters inside and beyond coastal state jurisdiction south of 63degreesN, especially catch statistics by species, fleets and gear: and if possible, indicate the biological status of the stocks. However, it has not been possible to make such divisions in the landings statistics with the information available to the Study Group.
The lack of detailed information on the biology of deep-water species, especially age structure, has precluded age-based stock assessment such as is carried out on many other commercially exploited fish stocks around the UK. The time series of catch and catch per unit effort are also too short for rigorous analysis. However, in 1998 the Study Group took the view that alternative assessment techniques should be employed, at least to indicate the current status of the stocks. The following table summarises the possible state of the stocks for some of the exploited species.
Species State of stock to the west of the British Isles
Blue ling Biomass considered to be below Upa and at or slightly below Ulim
Roundnose grenadier At present considered to be within safe biological limits
Black scabbardfish Unknown
Orange roughy Biomass considered to be outside safe biological limits (below Ulim) in ICES area VI and below Upa in area VII
Upa = The exploitable biomass below which the stock would be regarded as potentially depleted or overfished.
Ulim = The limit of exploitable stock biomass which indicates considerable depletion.
At present, the only management measure applied to the deep-water fisheries is the regulation of total fishing effort by EU vessels and Total Allowable Catch for monkfish/angler fish.

Current factors causing loss or decline

The current fisheries are largely unregulated (except for the general effort restrictions) and there is a major problem in recording what is actually being caught and landed. Misidentification of catches and landings by grouped categories such as `deep-water sharks` make the situation more difficult.
The bulbous heads and elongate bodies of many deep-water fish means that bottom trawls with mesh sizes appropriate for shallow-water fishing are likely to retain a higher proportion of juvenile fish or smaller non-commercial species. In common with most other fish with gas filled swimbladders, few survive being hauled to the surface following capture and are already dead when discarded.
Deep-water fish also have large scales and are almost devoid of mucus. Fish that are caught by the trawl but escape through the meshes while the trawl is being towed are, therefore, likely to sustain considerable external damage and probably suffer a high mortality.
Although many aspects of the biology of deep-water species are poorly understood, the general consensus is that they are long-lived, slow-growing species with a relatively high age at first maturity. This is a characteristic of stocks that can only sustain a low level of exploitation. It makes them particularly vulnerable to overfishing from which they are likely to take a long time to recover.
The food-webs in the deep-sea are complex, but all the evidence suggests that the commercial species are top-level predators on benthopelagic fish and invertebrates. The indiscriminate mortality of their food, in the form of bycatch in trawls, is likely to have an effect on exploited stocks.
In addition, bottom trawling for deep-water fish can damage reefs of the cold water coral Lophelia pertusa and thereby reduce the habitat for their associated communities. Norwegian research has indicated that some of the deep-water fishes form part of these communities and may be affected adversely.

Current action

  The European Union (EU) has complete authority for the conservation and management of marine fish and their fisheries; fisheries measures are implemented through Regulations of the Common Fisheries Policy (CFP). For this reason, the opportunities for the UK government to initiate unilateral marine fisheries management measures are limited. However, derogations that currently form part of the CFP allow individual states limited powers to apply additional measures to their national registered vessels.
  Fishing for deep water species within the EU 200 mile fishing limit, including UK waters, is subject to restrictions on effort under the `Western waters regime` (Council Reg. (EU) No 2027/95).
Total Allowable Catch (TAC) on monkfish . The monkfish landings from ICES sub-Areas IV (North Sea) and VI (west of Scotland) are covered by precautionary TACs. The fishing industry is now calling for an increase to allow for expansion of the monkfish fishery into deeper water.
Greenland halibut . The relatively new fishery for Greenland halibut, primarily in ICES Division IVa (northern North Sea), is not yet subject to regulation.
ICES Study Group on the Biology and Assessment of Deep-Sea Fisheries Resources. In 1998 the Group was asked to:
i) compile the available data on landings of deep-water species by ICES sub-Area or Division;
ii) update descriptions of deep-water fisheries in waters inside and beyond coastal state jurisdiction south of 63 degrees N, especially catch statistics by species, fleets and gear and, if possible, the biological status of these stocks;
iii) update the data on relevant biological information on deep-water species;
iv) update information on quantities of discards of deep-water species by gear type for the stocks and fisheries with a view to establishing a time series;
v) consider the possibility of carrying out assessments of fisheries for deep-sea resources and developing advice consistent with the precautionary approach.
ICES Advisory Committee on Fisheries Management (ACFM). ACFM has identified that some deep-water stocks are probably outside safe biological limits while the status of the others is unknown. Therefore, it recommends immediate reductions in fisheries that cannot be shown to be sustainable. All remaining fishing activity should be conducted in the context of effective management which emphasises documentation of fishing activity, and which can react appropriately to biological characteristics of the population.
European Commission FAIR Project (95/655) Developing deep-water fisheries: data for their assessment and for understanding their interaction with and impact on a fragile environment. The objectives of the three year project, which began in December 1995 and is co-ordinated by the Scottish Association for Marine Science (SAMS), Dunstaffnage, are to:
i) describe in detail the European deep-water fisheries with particular reference to geographic area, depth of occurrence, distribution, gear types and other parameters;
ii) make an inventory of existing survey data, support the working up of the data and ensure that these data sets are archived;

iii) describe and quantify the discards in the commercial fishery;

iv) carry out market sampling to accurately record the quantities of species landed, especially for those fishes that are not presently identified to species level;

v) investigate the biological parameters (eg age, growth and reproduction) of both target and by-catch species, which will be of value for the assessment and management of the resource.

The project covers a wide area of the continental slope from Iceland to Greece, but six of the 13 partners are either exclusively or partly working on the fish and fisheries of the continental slope to the Rockall Trough and cover all five objectives. A considerable amount of the new data provided to the ICES Study Group originates from this project. The project is not confined to marketable species but places considerable emphasis on non-target species and the total fish assemblages.

Before licences are awarded by the Department of Trade and Industry (DTI) for exploration of offshore blocks for gas and oil, operators are required to undertake an environmental impact assessment. If these assessments identify an unacceptable risk to the fauna in the area, including deep-water fish communities, the DTI will not issue a licence for exploration to proceed.

Action plan objectives and targets

Stabilise all stocks of commercially exploited deep-water species at or above safe biological limits by 2005.

Proposed actions with lead agencies

Policy and legislation

UK Fisheries Ministers should press the European Commission to initiate action in NEAFC to regulate these fisheries in line with the scientific advice of ICES. (ACTION: MAFF, SE)

Site safeguard and management

Little is known about stock identification and life history patterns of deep-water fishes. Indeed, the early life histories of many species are virtually unknown. It is, therefore, inappropriate to consider specific site safeguard measures at the present.

Species management and protection

The UK Fisheries Ministers should press the Council of Ministers to support fully any management or protection plans promulgated by the EU or NEAFC. (ACTION: MAFF, SE)

Advisory

The advice from ICES ACFM on management within the context of the precautionary approach is clear and concise. The UK government should put pressure on the European Commission to implement management measures that will ensure a sustainable fishery. (ACTION: MAFF, SE)
UK statutory and voluntary environmental groups should encourage their international partners to persuade their national governments to apply similar pressure to the EU Commission. (ACTION: JNCC)

Future Research and Monitoring

The UK government should continue to support UK participation in the ICES Study Group on the Biology and Assessment of Deep-Sea Fisheries Resources. (ACTION: DANI, MAFF, NERC, SE)
Carry out research into: the likely sustainable catch levels; technical measures to minimise damage to non-target and juvenile deep-water fish and associated species and habitats; and the importance of deep-water fish in the food chains to other marine organisms. (ACTION: DANI, MAFF, NERC, SE, SFIA)
Carry out research into the possible impacts of deep-water fishing on the total fish assemblage using datasets which pre-date the fisheries. (ACTION: JNCC, MAFF, NERC, SE)
Implement a programme of routine monitoring of landings to species level. (ACTION: DANI, MAFF, SE)
Improve methods of monitoring catches, such as satellite tracking of vessels, to minimise the risk of area mis-reporting. (ACTION: DANI, MAFF, NERC, SE, SFIA)

Communications and Publicity

Educate the public and the fishing industry on the special features of the deep-water fisheries and the fragility of the resource. (ACTION: DANI, JNCC, MAFF, SE, SFIA)

Links with other action plans

None given.

Lead partner(s)

Tom Blasdale, Joint Nature Conservation Committee Tel:01224 655708

Local implementation

No local implementation.

Publication details

Originally published in: UK Biodiversity Group Tranche 2 Action Plans - Volume V: Maritime species and habitats (October 1999, Tranche 2, Vol V, p57)
© Joint Nature Conservation Committee 2001, 2002, 2003, 2004, 2005, 2006, 2007