Ling

Icelandic ling in Va was considered a separate stock unit since 2007. A recent study based on genetic analysis appears to support ICES’ assumption of limited mixing and thus separate ‘assessment units’ at Iceland (Area Va), Norwegian Coast (Area II), and Faroe Islands and Faroe (Area Vb) (ICES, 2014a).

This stock was benchmarked in 2014 where a new analytical assessment specific for Ling in Va was adopted using a Gadget model (ICES, 2014a), moving from ICES category 3 in 2012 to category 1 at present (ICES, 2014c). This is an age–length structured model that can be used for stocks where age data are sparse, such as Ling in Va, and can use various types of data that can be included in the objective function. For 2014 assessment three types of data entered: length-based spring Icelandic groundfish survey indices, length distributions from survey and commercial fleets and age–length distribution from the survey and commercial fleets. Discards and bycatch, based on limited data, were considered negligible and not included in the assessment (ICES, 2014b). No information is available on weight-at-age and natural mortality of ling in Va. Natural mortality was assumed to be 0.15 for the analytical assessment (ICES, 2014a). Efforts are being made to improve age reading of ling and now, aged otoliths are available from the 2005, 2010 to 2012 spring surveys and from 2012 commercial catches.

Before 2007 ling in the NE-Atlantic was assessed as a single management unit, between 2007 to 2012 ling in Va was assessed based on trends in survey indices from the Icelandic spring (since March 1985) and autumn survey (since October 1996), carried out by the MRI. In 2012 the stock was assessed as stocks for which survey-based assessments indicate trends (ICES, 2014a,b).

ICES advice was based on an approach for data-limited stocks for years 2013 and 2014. Based on the MSY approach and a new analytical assessment, ICES advice for 2015 is that catches should be no more than 14.4 (000 t)(ICES, 2014a).

Recruitment was high from 2004 to 2010, but has decreased to very low levels since then, being the main source of uncertainty at present. The stock–recruitment relationship indicates a response to changes in the environment and/or stock composition; remaining uncertain what the main drivers behind these changes are (ICES, 2014a). Long-term projections for F_MSY = 0.24 were run excluding recruitment spike in the years 2004-2010. This was done for taking into account low recruitment indices in recent years and the related uncertainty. Projections indicate that SSB, harvestable biomass and catch levels will peak at 14.3 (000 t) in 2016 but decrease after 2016 to 10.7 (000 t) in 2020 (ICES, 2014a).

Following catch limitations according to advice for 2015 it is expected that SSB will reach 57.9 (000 t) in 2016, meaning a 9% increase of SSB from 2015 to 2016. Considering the benchmark of the stock and assumptions taken for the long-term projections the degree of precaution in advice is considered to have increased.

Last updated on 28 Aug 2014

The stock was benchmarked in 2014 by ICES adopting a new analytical assessment (Gadget), in conformity with the ICES MSY approach.

F_MSY is set at 0.24 (ICES, 2014a,b; MRI, 2014a). The yield per recruit gave an estimate of F_MAX equal to 0.24, which is in line with the estimated F_MSY (ICES, 2014a). B_Lim was estimated at 8.1 (000 t) as the lowest estimated SSB and spawning stock at MSY, B_MSY was estimated at 29.9 (000 t)(ICES, 2014a). However, B_PA/ MSY B_Trigger was set at 9.5 (000 t)(ICES, 2014a) to take into account recent low levels of recruitment and its associated uncertainty.

Surveys coverage is considered appropriate. Sampling is considered good from commercial catches for the main gears longline and trawls covering the spatial and temporal distribution of catches for those fleets but less so for gillnets (ICES, 2014a). Currently the longline and trawl fishery represent 97% of the total fishery, while the remainder is assigned to gillnets (ICES, 2014b). ICES alert that if those proportions change dramatically, so will the total catches as the selectivity of gillnets is substantially different, catching larger ling (ICES, 2014a).

In 2012, an F_proxy (total catch/survey biomass index) of 1.5 was considered to be an appropriate advisory F_proxy to base catch advice for 2013 and 2014 (ICES, 2014a; MRI, 2013).

Total biomass is 75.4 (000t). SSB is above the precautionary reference point B_PA, which is consideredB_Trigger. The ICES Gadget assessment indicates that ling in Va is at present in a good state. SSB has increased since 2000 and is now estimated close to the highest SSB estimate in the time-series (ICES, 2014a). Recruitment peaks were observed between 2003 and 2010, and these year classes may contribute to the current increase in biomass indices (ICES, 2014a).

However, recruitment index of ling, defined as ling smaller than 40 cm or age < 3, has decreased since then and is estimated in 2013 to have been the lowest observed (ICES, 2014a). In 2011 it decreased by around 25% and for the last two years the index has fallen by a factor of three from its level in 2010 (MRI, 2014a). Click to see the graph of estimated year class size at age 3 (in millions) for Ling (MRI, 2014a).

The stock–recruitment curve indicates a response to changes in the environment and/or stock composition, being uncertain what the main drivers behind these changes are (ICES, 2014a; MRI, 2014a), thus ICES Advice stresses that the uncertainty on the recruitment in most recent years is high (2014b).

F for fully selected ling (age 14-19) has decreased from 0.62 in 2008 to 0.26 in 2013 due to increasing population, being roughly the FMSY of 0.24 estimated for the 2014 benchmark. Landings for the fishing year 2012/2013 were at around 12.5 (000 t), the proportion taken by longliners (67%) have been increasing since 2010, bottom trawl (30%) is almost stable, and gillnet and Danish seine (3%) have decreased from around 20% since 2000 (ICES, 2014a,b).

Last updated on 28 Aug 2014

From 1950 to 1971 landings of ling in Va ranged between 7,000 to 15, 000 tons and decreased from 1972 – 2005 to between 3,000 to 7,000 tons as a result of foreign vessels being excluded from the Icelandic Exclusive Economic Zone (EEZ). Landings have increased substantially year on year from 2001 to 2010, reaching 11,000 tons at the end of that period. In 2011 catches decreased to around 9,600 tons but reached 12,000 tons in 2012 and 2013 (ICES, 2014a).

SSB has been relatively stable from early 1980s until 2000 (~20,000 tons), it has increased since 2000 and is now estimated close to the highest SSB estimate in the time-series (~55,000 tons). Recruitment has increased from 2003 to 2010, but has decreased since then and is estimated in 2013 to have been the lowest observed (ICES, 2014a). Simulations suggest that the stock size will be significantly reduced due to recruitment failure and it will result in catches decrease to lower than 10,000 tons by 2020.
Click to see a graph of projected biomass of Ling in Va according to F_MSY (ICES, 2014a).

TAC have been increasing from 3,000 tons in 2001/2002 to 14,000 t in 2013/2014 in relation to higher biomass indexes.

A reduction in around 42% in F for fully recruited ling (age 15-19) from 2008 to 2013 was observed with increasing population.

Fisheries management in Iceland is the responsibility of the Ministry of Fisheries and Agriculture. A system of transferable boat quotas was introduced in 1984. Until 1990, the quota year corresponded to the calendar year but since then the quota, or fishing year, starts on 1 September and ends on 31 August the following year. Ling in Va has been managed by TAC since 2001/2002 fishing year.

Individual transferable quotas (ITQs) allows free transferability of quota between boats, which can either be on a temporary (one year leasing) or a permanent (permanent selling) basis, it also allows for some but limited flexibility with regards converting a quota share of one species into another within a boat, allowance of landings of fish under a certain size without it counting fully in weight to the quota, and allowance of transfer of unfished quota between management years (IMFA, 2014c). These measures constitute a no-discarding strategy, retained species are recorded and landed (DNV, 2013).

Ministry of Fisheries and Agriculture allocation of quotas is based on stock assessments and scientific advice by the Marine Research Institute, reviewed by relevant committees of the ICES prior to publication. Managers’ decisions take also into account social and economic factors (IMFA, 2014a).

From 2001/2002 to 2006/2007 set TAC was in line with MRI advice. From 2007/2008 to 2009/2010 fishing years, set TAC has exceeded the MRI advice by 1.0 (000 t). From 2010/2011 to 2013/2014 set TAC has been almost the advised, and has been increasing from 7.5 to 13.5 (000 t) in response to an increase in stock biomass (MRI, 2014a; ICES, 2014a). MRI advice is the same as ICES´ for 2014/2015. However, in several years (2007/8, 2008/9, 2011/12 and 2013/14) MRI´s advice has been higher than ICES advice.

No strategy with the long-term objectives is publicly available, nor is the rationale for setting the Ling TAC. MRI is working on long term management strategy for main the marine stocks. Long term management schemes (with harvest control rules) for cod, capelin and summer spawning herring are already in force (MRI, 2014b).

No specific area/seasonal closures are set for Ling in Va, there are closures established to protect known spawning grounds and a temporary closure system to protect juvenile fish and reduce the incentives to discard. Fishing is prohibited for 2-3 weeks in areas where the number of undersized fish in the catches has been observed by inspectors to exceed a certain percentage of main fished species. Inspectors from the Directorate of Fisheries supervise these closures in collaboration with the Marine Research Institute and the Coast Guard (IMFA, 2014a). There are several selectivity measures, such as a mesh size and devices for excluding juveniles in the groundfish fisheries are also mandatory in certain areas (IMFA, 2014a). The effects of these measures have not been evaluated (ICES, 2013).

Last updated on 28 Aug 2014

Although the stock is in a healthy state and is projected to remain so under current catch scenarios, so no recovery plan is currently required, there is no known management strategy with a harvest control rule which defines measures to be adopted should the biomass decrease to low levels.

Stock of Ling (Molva molva) in Division Va is caught mainly in Icelandic EZZ by Icelandic, Norwegian and Faroese fleets. Landings have generally exceeded the TAC by 20-50% of set TAC, as a result of the allowance for exchanging ITQs of one species for another and between fishing years and catches by Norway and the Faroe Islands by bilateral agreement. The level of those catches is known in advance (~1,200 t) but has until recently not been taken into consideration by the Ministry when allocating TAC to Icelandic vessels (MRI, 2013). Since 2010/2011 this issue has been addressed by setting lower ITQs to Icelandic vessels, thus the percentage of overshoot has decreased from 53% in 2009/2010 fishing year, to 35% in 2010/2011, 24% in 2011/2012 to 8% in 2012/2013 (ICES, 2014a).

Main gears in this fishery are: longline (67%), bottom trawl (30%), gillnet and Danish seine (3%) (ICES, 2014b). The Directorate of Fisheries and the Marine Research Institute conduct research and estimate discarded catches and results indicate insignificant discards by the Icelandic fishing fleet (ICES, 2014a).

In 2009, an electronic logbook (e-logbook) system was implemented.

Benthos: effects of demersal trawling on large structural biota such as cold-water corals and sponges are considered to be severe. MRI is maintaining a coral mapping program, to collect data especially on location and distribution of cold-water corals such as the long-lived reef-building Lophelia pertusa, highly vulnerable to physical damage (DNV, 2012a). This species is in the OSPAR List of Threatened and/or Declining Species and Habitats. New information on distribution allowed creation of new protected areas, reaching a total of 14 (Vottunarstofan Tún., 2014). Click here to see a map of all areas to protect cold-water corals in Iceland waters.

Reptiles: Leatherback turtle (Dermochelys coriacea) has been recently listed as Vulnerable (2013 IUCN Red List, 2014) (DNV, 2012a). There are no records of marine turtles having been caught in any type of fishing gear in Icelandic waters (IMFA, 2014d).

Fish: Grey skate (Dipturus batis) is critically endangered (2006 IUCN Red List). It is caught as bycatch mainly by longliners. General conservation measures are in place which will help reduce impacts on the vulnerable populations (e.g. large-scale area closures), but do not address grey skate conservation specifically. A more effective approach has been recommended (Vottunarstofan Tún., 2014). Atlantic halibut (Hippoglossus hippoglossus) is Endangered (1996 IUCN Red List), there is a rebuilding plan in Iceland since 2012 (Regulation 470/2012), which requires live Atlantic halibut to be returned to the sea (Vottunarstofan Tún., 2014). In addition, Blue fin tuna (Thunnus thynnus) is endangered (2011 IUCN Red List), Basking shark (Cetorhinus maximus), Porbeagle (Lamna nasus) and Common thresher shark (Alopias vulpinus) are Vulnerable (2005, 2006, 2009 IUCN Red List), Greenland shark (Somniosus microcephalus), Sharpnose skate (Dipturus oxyrinchus), Blue Shark (Prionace glauca) are Near Threatened (2006, 2007, 2009 IUCN Red List). Blue, thresher and porbeagle sharks and blue fin tuna are captured occasionally. All are pelagic feeders and are unlikely ever to be taken in demersal trawls. However, basking shark is vulnerable to capture in demersal fishing gear. (DNV, 2012a; IUCN, 2014).

Seabird: community in Icelandic waters is composed of relatively few but abundant species, accounting for roughly ¼ of total number and biomass of seabirds within the ICES area, being auks and petrel are most important groups. Most seabirds feed on small fish, like capelin (Mallotus villosus) in north Icelandic waters and sandeels (Ammodytidae) in south Icelandic waters (ICES, 2014a).

Marine mammals: Of the commonly recorded cetacean species in Icelandic waters, Blue whale (Balaenoptera musculus), Sei whale (Balaenoptera borealis) and Fin whale (Balaenoptera physalus) are Endangered (2008 IUCN Red List), and the Sperm whale (Physeter macrocephalus) is Vulnerable (2008 IUCN Red List) (DNV, 2012a; IUCN, 2014).

Interactions with and impacts on Protected, Endangered and Threatened (PET) species by the fishery targeting mainly cod are very unlikely, apart from a small risk of seabird entanglement from longliners (DNV, 2012a). There is a MRI marine mammal and seabird observer program and fishing vessels are encouraged to record marine mammal and seabird bycatch in the e-logbook, however data on interactions with and impacts on PET species by the fishery is not available. Knowledge of impacts by fishing gear is difficult because a simple categorization of boats among the different fisheries types is impossible, as many change gear depending on fish availability in relation to season, quota status of the individual companies, etc. (ICES, 2011).

No target or limit reference points have been adopted by managers for PET species.

Ling constitute only 2.5% of total demersal removal from the Icelandic ecosystem (10,000 of 404,413 tons of total demersal species in 2011, Statistics Iceland, 2013). The longline ling fishery in Va has changed from a bycatch fishery in 2000–2005 to more of a mixed fishery since then. Longliners account for 67% of ling landings in 2013, while trawlers for 30% as bycatch (mostly otter trawl and some lobster trawl). The remainder 3% is caught as bycatch by vessels using danish seine and gillnet.

Discarding is banned by law in the Icelandic demersal fishery. Based on limited data, discard rates in the Icelandic longline fishery for ling are estimated very low (<1% in either numbers or weight) (ICES, 2014a). Measures in the management system such as converting quota share from one species to another are used by the fleet to a large extent and this is thought to discourage discarding in mixed fisheries.

Discarding of non-commercial species is permitted, however estimates are not available. Information on their status and trends are collected research surveys. Sharks and skates are known to be taken as bycatch in Icelandic fisheries but catch rates are incomplete and the status of stocks is unknown (ICES, 2014d).

While there is no statutory requirement for Icelandic-registered fishing vessels to record marine mammal bycatch, they are encouraged to do so in the e-logbook. In April 2009 a program of monitoring all marine mammal and bird bycatch in regular observations of the Fishery Directorate was implemented covering all types of fisheries and these data have been reported to ICES (ICES, 2010).

In recent years there has been an increased effort on mapping the distribution of benthic communities and habitats vulnerable to trawling in Iceland (DNV, 2012b). The effects of otter trawling have been investigated and the results suggested that only a few species were affected by trawling. Effects of trawling on large structural biota such as corals and sponges are considered to be more severe. Although little evidence exists on the effects of trawling on this group of animals, it is likely that their distribution is now more fragmented than prior to fishing (MRI, 2014).

Important and vulnerable ecosystems such as cold-water coral (CWC) reefs, with the predominance of Lophelia pertusa, occur mainly in the southern Icelandic coast (Hall-Spencer and Stehfest, 2009). Implemented in 2009, the e-logbook system helps to monitor the interaction of the fishery (based on the fishing effort) with CWC (Burgos and Ragnarsson, 2012). The BIOICE program has been in operation since 1992 with the aim of producing a basic inventory of benthic fauna within Icelandic territorial waters. Following a scientific mapping, 14 coral areas with Lophelia pertusa have been closed for all fisheries using bottom contact gear (Vottunarstofan Tún ehf., 2014).

Other vulnerable benthic habitats around Iceland have not been closed to fishing, vulnerable marine ecosystem indicator species include also sea pen fields; crinoids; erect bryozoans; sea squirts; cerianthid anemone fields; and sponges that constitute sponge grounds or aggregations (Vottunarstofan Tún ehf., 2014).

Last updated on 28 Aug 2014

Several areas off Icelandic waters are closed temporarily or permanently to all fisheries, presumably to protect not only juvenile fish stocks, but also other species groups and benthic habitats (ICES, 2011; DNV, 2012b); effects are not assessed (ICES, 2013). 14 coral areas of Lophelia pertusa have been closed to fisheries with bottom contact (Burgos and Ragnarsson, 2012; Vottunarstofan Tún ehf., 2014). In addition, a quick-response (real-time) closure system has been in force since 1976, aimed at protecting juvenile fish. Fishing is prohibited for at least two weeks in areas where the number of small fish in the catches has been observed by inspectors to exceed threshold percentages (25% or more of <55 cm cod and saithe, 25% or more of <45 cm haddock and 20% or more of <33 cm redfish) (DNV, 2012).

Preliminary results indicate that relatively small areas closed for a short time do not contribute for the protection of juveniles. On the other hand, several consecutive quick closures often lead to closures of larger areas for a longer time and force the fleet to operate in other areas. The effect of these longer closures has not been evaluated. Spawning areas have been closed during the spawning season for all fisheries, from 1995, for 2-3 weeks, to protect the spawning stock (ICES, 2013).

Seven designated Nature Reserves, established from 1974 to 1988, and one Conservation Area, designated in 1995, exist along the Icelandic coast and off Surtsey Island totaling 3,507 km2 (Wood, 2007). Iceland has 39 marine protected areas (in accordance with the OSPAR definition), including 11 relative large areas and 16 offshore areas, which are closed year-round or seasonally or have restricted access for fisheries management purposes (Hoyt, 2005).