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| Fact Sheet Title Fact Sheet |
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| Herring - West of Scotland |
 | Herring in Divisions VIa (South) and VIIb,c |
| | Data Ownership | | This document provided, maintained and owned by International Council for the Exploration of the Sea (ICES) , is part of ICES Advice data collection. |
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| ident Block | ident Block | | | | Species List: | | Species Ref: en - Atlantic herring, fr - Hareng de l'Atlantique, es - Arenque del Atlántico, ru - Сельдь атлантическая |
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| ident Block Herring - West of Scotland Aq Res Ident Aq Res Ident Aq Res Ident | fao Div |
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| 27.6.a | Northwest Coast of Scotland and North Ireland or as the West of Scotland (Division 27.6.a) |
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| 27.7.b | West of Ireland (Division 27.7.b) |
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| 27.7.c | Porcupine Bank (Division 27.7.c) |
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| Aq Res | Biological Stock: Biological Stock
Value: Sub-Regional
Management Unit: Management Unit
Reference Year: 2012
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| Considered a management unit: An aquatic resource or fishery is
declared as [Fishery] Management Unit if it is
effectively the focus for the application of selected
management methods and measures, within the broader
framework of a management system. According to the FAO
Glossary for Responsible Fishing, "a Fishery Management
Unit (FMU) is a fishery or a portion of a fishery
identified in a Fishery Management Plan (FMP) relevant
to the FMP's management objectives." FMU's may be
organised around fisheries biological, geographic,
economic, technical, social or ecological dimensions ,
and the makeup and attribute of a fishery management
unit depends mainly on the FMP's management
objectives. |
| Jurisdictional distribution: Jurisdictional qualifier (e.g.
"shared", "shared - highly migratory") of the aquatic
resource related with its spatial distribution. |
| Environmental group: Classification of the aquatic
resource according to the environmental group (e.g.
pelagic invertebrate, or demersal fish) to which the
species belong. |
| | | | | | Aq Res State Trend  | Figure 4.5.17.1  |
An exploratory assessment (including survey data from the Malin shelf acoustic survey) shows that SSB is below B lim. The exploratory assessments show different trends in F: one assessment shows a stable trend at high values, whereas another one shows a decrease since 2006. In both cases F is still above F MSY. Recruitment has been low since 2000.
Habitat Bio Depth Zone: Shelf 50 200m. Vertical Dist: Pelagic.
This autumn and winter/spring-spawning stock is considered a part of the Malin Shelf Stock Complex. The stock identity is complex as the juveniles mix with those from the west of Scotland and the adults mix with those from the Irish Sea and Division VIaN over the shelf areas to the west of Scotland after spawning. Fish of this stock are expected to mix with VIa North herring in that area. Spawning and nursery areas are sensitive and vulnerable to anthropogenic influences. Gravel extraction or disturbance in the close vicinity of any herring spawning will disturb that spawning activity and will reduce the available area for successful spawning.
Geo Dist Geo Dist: Shared between nations Water Area Overview Spatial Scale: Spatial Scale
Ecoregion: Celtic Seas
Water Area Overview  | | Water Area Overview Herring - West of Scotland
| fao Div | 27.6.a: Northwest Coast of Scotland and North Ireland or as the West of Scotland (Division 27.6.a) | | 27.7.b: West of Ireland (Division 27.7.b) | | 27.7.c: Porcupine Bank (Division 27.7.c) |
| | | | | | Water Area Overview |
Water Area OverviewHerring - West of Scotland Aq Res Struct Biological Stock: Biological Stock Exploit The fisheries
The fisheries take place using pelagic trawls in quarter 1 and 4. The low TAC has led to a much shorter fishing season now consisting of only a few days, compared to a five months fishery prior to 2003.
| Catch distribution | Total landings (2011) = 6919 t, 100% pelagic trawls. |
Effects of the fisheries on the ecosystem
The human consumption fisheries for herring are considered relatively clean, with little bycatch of other fish and cetaceans.
Bio Assess Sci Advice
ICES advises on the basis of MSY approach that there should be no catches of this stock unless a rebuilding plan is implemented.
ICES advises that activities that impact on the seabed should not take place in spawning grounds unless they can be shown not to have a negative impact on spawning, larval production or stock dynamics.
Results  | | Figure 5.4.17.1 Herring in Divisions VIa (South) and VIIb,c. ICES estimates of catches (tonnes), recruitment, SSB (‘000 tonnes) and fishing mortality from a separable VPA (terminal fishing mortality=0.5) and ICA run. |
Assess Models Quality consideration
The exploratory separable VPA assessment is uncertain as it is based on catch-at-age data only. The spatially and temporally truncated fishing season results in catch-at-age data that may be less informative of overall population age structure. The current survey-series is short (2008–2011) and has been used in a new exploratory ICA assessment. This ICA assessment gave similar results to the separable VPA for SSB, but resulted in very different trends in F. The inclusion of fisheries-independent information in the ICA run is considered to be an improvement in 2012. There is some evidence of a stronger (2008) cohort recruiting to the stock, but it is not yet possible to estimate its strength.
Efforts to split the Malin shelf acoustic survey data according to stock component should continue. Improved information is required to the extent to which catches of this component are taken in Division VIaN.
Scientific basis
| Assessment type | Trends-based exploratory assessments (Separable VPA, FLICA). | | Input data | Commercial catch-at-age data. Acoustic survey data (MSHAS). | | Discards and bycatch | Not considered relevant. | | Indicators | None. | | Other information | A benchmark is suggested for 2014. | | Working group report | HAWG |
Management Management: Management Management plans
There is currently no explicit management plan for this stock. A rebuilding plan was proposed by the Pelagic RAC in 2011. ICES has not been requested to evaluate this plan.
Sources
The above excerpts are from the first two pages of the ICES advice, the supporting information to this advice can be read in full at the following reference:
ICES. Herring in Divisions VIa (South) and VIIb,c. Report of the ICES Advisory Committee, 2012. ICES Advice, June 2012.
 http://www.ices.dk/committe/acom/comwork/report/2012/2012/her-irlw.pdf |
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