Lobster, Norway, Langoustine, Dublin Bay prawn or scampi

Nephrops norvegicus

Method of production — Caught at sea
Capture method — Pot or creel
Capture area — North East Atlantic (FAO 27)
Stock area — Skagerrak and Kattegat
Stock detail

3a (FU 3 and 4)


Picture of Lobster, Norway, Langoustine, Dublin Bay prawn or scampi

Sustainability rating two info

Sustainability overview

The stock status of Nephrops in this area is unknown, but there appears to be no concern for either the biomass or the fishing mortality.

Nephrops fisheries are managed mainly using area restrictions, a total allowable catch, effort restrictions and technical measures. However, these areas are often too large to manage Nephrops effectively. This has historically resulted in fishing vessels concentrating their effort on favoured fishing grounds in a largely uncontrolled way, leading to overfishing and depletion of some Nephrops populations in the past, like in the Farn Deeps. Therefore, scientists advise that management should be implemented at the functional unit (FU) level.

Trawl fisheries for scampi (Nephrops) are associated with large quantities of bycatch, including overfished species such as cod, haddock and whiting. Pots or creels are a much more selective method of fishing, as immature or egg carrying animals can be returned to the sea alive and bycatch of overfished species is not an issue. The method also tends to produce a larger, higher quality product.

Biology

Norway Lobster (also known as langoustine or scampi) live in burrows on the seabed. They are limited to a muddy habitat and require sediment with a silt and clay content to excavate burrows. Their distribution therefore is determined by the availability of suitable habitat. They occur over a wide area in the North East Atlantic, from Iceland to North Africa and into the Mediterranean, and constitute a valuable fishery for many countries. Males grow relatively quickly to around 6 cm, but seldom exceed 10 years old. Females grow more slowly and can reach 20 years old. Females mature at about 3 years. In the autumn they lay eggs which remain attached to the tail for 9 months (known as being “berried”). During this time the berried females rarely emerge from their burrows and therefore do not commonly appear in trawl catches, although they may be caught using baited creels. This habit of remaining in their burrows has probably afforded their populations some resilience to fishing pressure. Egg hatching occurs in the spring, and females emerge in spring/summer to moult and mate.

Stock information

Criterion score: 0.25 info

Stock Area

Skagerrak and Kattegat

Stock information

Summary
The stock status of Nephrops in this area is unknown, but there appears to be no concern for either the biomass or the fishing mortality.

Justification
The nephrop biomass in this area is unknown relative to reference points but stock size has recently increased. The harvest rate is below the reference point (Maximum Sustainable Yield). The species has a high resilience.

Management

Criterion score: 0.5 info

There is currently no management plan in the Kattegat-Skagerrak area. There are multiple management measures and a variety of enforcement is employed in the fishery. The main management measures include: an minimum conservation reference size (MCRS) of 32mm, but Norway apply a 40 mm MCRS. Additionally, in creel fisheries, Nephrops that are below the MCRS can be discarded because they are more likely to survive discarding, compared to when they are caught in generic nephrop trawls.

Whilst management measures exist in the fishery, quota management may not be wholly effective: quota is not applied at the functional unit level and therefore, the stock is at risk of overfishing. Nephrops stock assessments are conducted by the International Council for the Exploration of the Sea (ICES). Stock assessments are produced for 33 areas across the Northeast Atlantic, called functional units. However, management is applied to a separate 18 areas, called management units. These management units broadly overlap with the functional units, but not very effectively, previously resulting in overfishing. Therefore, scientists advise that management should be implemented at the functional unit level, to better protect the Nephrops.

The quota used in this area has been in line with scientific advice: ICES advised that catches in 2017 should be no more than 13099 tonnes, in that year ICES estimated total catch was 6234 tonnes. In this area, there is a high discard ratio of undersized Nephrops (representing around 63%), but the most recent ICES report shows that discard rates represent about a fifth of landings.

Capture Information

Criterion score: 0 info

Nephrops live in burrows in muddy seabeds. Therefore, to capture Nephrops, fishing vessels use fishing gear near or on the seabed such as demersal trawls and creels. Nephrops are predominantly caught using demersal trawls. Pots or creels are a much more selective method of fishing compared to the trawls as immature or egg carrying animals can be returned to the sea alive.

Bycatch
Skippers generally aim for where nephron populations are likely to be highest, therefore, bycatch in creel fisheries is generally low. Bycatch generally includes whelks, and hermit crabs. The discarded catch is small (around 6% of total catch) and usually includes brown crab, velvet crab and lobster, which are likely to survive discarding.

Habitat
The impact of creels on the seabed is likely to be low: they are normally set on a mud surface but can sometimes impact sessile species. Though, the impact of creels on sea pens is considered minimal.

Creeling produces a larger, higher quality product.

There are a number of Marine Protected Areas (MPAs) in this Functional Unit which are in need of protection from damaging activities. The nephrops fishery is known to overlap with parts of these MPAs, but it is not clear by how much. For these components, MCS considers bottom trawling in MPAs as a default red rating unless there is evidence (such as an environmental impact assessment (EIA)) indicating the activity does not damage the integrity of the site.

References

ICES Advice 2018. Norway lobster (Nephrops norvegicus) in Division 3.a, functional units 3 and 4 (Skagerrak and Kattegat) . Published 29 June 2018. https://doi.org/10.17895/ices.pub.4433. Available at: http://ices.dk/sites/pub/Publication%20Reports/Advice/2018/2018/nep.fu.3-4.pdf