Sandeels nei

Since 2010, stock assessment is conducted separately for each of the sandeel management areas in the North sea. A Seasonal age based analytical model (SMS-effort), based on data from dredge surveys and total international fishing effort, is used for the assessment (ICES 2018). According to ICES, this combination of the new assessment model “SMS-effort” with the specific area based approach have much improved the quality of the assessment, and removed retrospective bias in Fishing mortality (F) and Spawning stock Biomaass (SSB) estimates for the recent years (ICES, 2012a). The quality of the assessment is considered to be good (ICES, 2015). In 2014 and 2015 occurred some misreporting of catches taken in SA 1, but reported to SA 3 (Central Eastern North Sea). The catches and fishing effort in SA 3 were revised based on information from VMS and previous catch distributions (ICES 2018).

Following the MSY approach (Escapement strategy) for a short-lived species, ICES advises that the catch in 2018 should be no more than 134,461 t, a large drop from the previous 255,956 t. This is due in part to the low recruitment in 2017 as the large year class of 2016 will make up the bulk of the fishery in 2018 (ICES 2018)

ICES recommended that management measures similar to those applied in the Danish fishery, should be taken to avoid similar misreporting in the future by other countries (ICES 2018)

A new proposed method to monitoring the sandeel fishery based on real-time monitoring was made by the Danish Ministry of Food, Agriculture and Fisheries in 2016. This method is similar to the 2012 request; however, this new method includes an option to provide TAC advice through a TAC-setting procedure that sets a TAC from the observed catch rates of age 1 sandeel in the early 2016 fishery (in the period 15 April to 6 May 2016). This proposal was reviewed by ICES and considered suitable for monitoring sandeel abundance in SA1 (ICES, 2016b). 

The stock is considered to be at “Above escapement trigger/ Full reproductive capacity”. The spawning stock biomass (SSB) is estimated at around 278 thousand tonnes (ICES 2018). In 2018, the reproductive biomass has increased substantially but with variation from a near time series low in 2014. Recruitment in 2015 and 2017 were low, however. Fishing mortality (F) was below long-term average and in 2016 was the lowest value estimate of the time-series, but has increased substantially in 2017; this value is however less certain as it is the terminal estimate (ICES 2018). 

Since 2011 separated quotas are defined for each of the seven management areas. EU has been using a real-time monitoring for setting TACs (more information at Scientific Advice section). For 2018, European Commission  set the TAC and quotas provisionally at zero before ICES scientific advice has been released. The EU established the final TAC value for Dogger Bank (SA 1r) in 2018 and followed the scientific (EUR-Lex 2018) advice setting the area quota at ~134,000 t

Temporal closures from January 1st – March 31st and from August 1st – December 31st, apply to all management areas for towed gears with a mesh size less than 16 mm (e.g. European Commission 2017). No specific management plan is known for this fishery (ICES 2018).

As of 1 January 2015, the landing obligation applies also to fisheries for industrial purposes (e.g. fisheries for capelin, sandeel and Norwegian pout).

To avoid area misreporting, only one fishing area per trip is mandatory for the Danish fishery since 2015 (ICES, 2016a).

Biomass reference points:

MSY Approach: A MSY B_escapement has been defined at 145,000 tonnes (= B_pa). ICES introduced a ceiling on Fishing mortality (F) level on the escapement strategy to ensure the ICES precautionary criterion (probability of Spawning Stock biomass (SSB)  being below B_lim is ≤ 5%) is met. The value of F_cap was defined at F_cap=0.49.

Precautionary approach (PA): Lower limit threshold biological reference point, B_lim, has been defined at 110,000 tonnes, corresponding to lowest SSB at which a high recruitment is observed. B_pa has been defined at 145,000 tonnes (ICES 2018).

Prior to 2010 set TACs referred to the entire North Sea area (which encompasses the zone IIIa, EC waters of Division IIa and Subarea IV). Historically compliance has been strong in the North Sea sandeel fishery; with the exception of 2007 and 2010, overall landings in the North Sea have not surpassed set TACs in recent years (ICES, 2013a).

For the Dogger Bank area specifically, landings have considerably surpassed the TAC in 2012, 2014, 2015 and 2016. A total of 164,770 tonnes of sandeel were landed in 2015, well above the set TAC for this management area (133,000 tonnes). In 2016, landings (12,751 tonnes) no overpassed the total TAC (13,000 tonnes). With the reformulation of the management area into SA 1r,  the total catch estimate for this area in 2016 (15,264 tonnes) it was higher than the previous area SA 1. Discards are considered to be negligible (ICES 2017).Preliminary catches for 2017 appear to be in-line with the scientific advice (ICES 2018).

In the past, misreporting occurred of catches taken in SA 1, but reported to SA 3 (Central Eastern North Sea) which ICES has reallocated a total of 44,000 tonnes in 2014 and 15,000 tonnes in 2015 from SA 3 to SA 1 during the 2017 assessment. This situation seems to be due the management system operated with individual vessel quotas by sandeel area (SA), which created the incentive and opportunity for misreporting through allocating small shares to vessels in the low TAC areas (ICES, 2015). Management measures adopted in 2015 (only one fishing area per trip) eliminated the misreporting issue for Danish catches. However, this situation seems to occur for other nations which ICES recommends that similar management measures should be implemented (ICES 2018).

In the North Sea ecosystem, sandeel is considered a very important prey species for a variety of predators, including fish, marine mammals and seabirds. In general, fishing on sandeel aggregations at a distance less than 100 km from seabird colonies has been found to affect some surface feeding bird species, especially kittiwake (Rissa tridactyla; IUCN, 2012: “Least Concern”) and sandwich tern (Sterna sandvicensis; IUCN, 2012: “Least Concern”) (ICES, 2010a; ICES, 2010d). There are some concerns that the industrial fishery may indirectly impact predatory fishes by depriving them of food (Engelhard et al., 2008; Cook et al., 2014). According to Daunt et al. (2008), years of bad recruitment in sandeels have led to poor breeding success in seabirds (e.g., little tern and black-legged kittiwakes) that feed mainly the 0-group cohorts. Fish and mobile marine mammals’ populations are assumed to be less vulnerable to local sandeel depletion (ICES, 2010c).

Other than trophic effects direct impacts of the fishery on ETP species is not thought to be problematic (Rice et al. 2017).

Sandeel catches include several Ammodytoidei species but consist largely of Ammodytes marinus. At some of the grounds in the Dogger Bank area the smooth sandeel Gymnammodytes semisquamatus can be important (ICES, 2007c). The levels of bycatch in the sandeel fishery are considered to be very low. In years with low abundance of sandeel, bycatches of sprat, herring, mackerel and whiting may occur, however in recent years, those species represented less than 1% of sandeel (Scheveningen Group, 2014). Heath et al. (2014) alerts for possible ecological effects of eliminating fishery discards.

Sandeel fishing effort on the Dogger Bank is concentrated when and where sandeels are most available and where, in turn, they are locally preyed upon by at least 10 predatory fish species (e.g. dab, whiting, lesser weever and grey gurnard), including 8 commercially important ‘human consumption’ species. Despite this, direct interactions with these important predators is considered low as a result of the gear used and the overall fishing method employed by the fleet (Rice et al. 2017). This fishery is under the landing obligation for the EU (Rice et al. 2017).

Information on exact fishing location is avail bile thought the vessel monitoring system (VMS) used by the fleet. Additionally, detailed habitat maps of the normal fishing grounds are also available. However direct observational studies of the physical impacts of this gear on the seabed are not available (Rice et al. 2017).

While this fishery uses bottom trawling gear, impacts to the sea-bed are not thought to be problematic.  This is in part due to the lack of tickle chains, sweeps, or bobbins, other gear on the bottom of the net near the foot rope. Additionally, the sand eel fishery is conducted in areas of sand, which tend to be high energy environments in their natural state. As such the limited disturbance of the gear is not thought to be important when compared to natural disturbances (Rice et al. 2017).

Several coastal areas and zones of known deep-water coral communities in the North Sea have been closed to fishing, in order to protect both benthic communities/habitats and juvenile demersal fish (OSPAR, 2009).