Celtic Sea
Abstract:
Data used to produce figures come from the STECF working group on Fisheries Dependent Informations . Please note that time series might be incomplete for some countries/indicators.
You can check 
if data were provide or not for a couple of country/year.
Landings
The Celtic Sea area is a region that extends from the shelf area west of Scotland (ICES division VIa) down to the western Channel south of England (ICES division VIIe). The Celtic Sea proper corresponds to ICES divisions VIIf-k and is limited to the west by the slope of the Porcupine Seabight and the Goban Spur. Beyond the Porcupine Seabight, to the west of Ireland, the Porcupine Bank forms a large extension of the shelf, which is limited to the west by the Rockall Trough. The variety of habitats in the Celtic Sea accommodates a diverse range of fish, crustacean and cephalopod species that support a wide variety of fisheries targeting different species assemblages from pelagic to demersal.
Despite pelagic trawling being responsible for more landings than any other gear types in the Celtic Sea this fishery only accounts for a small fraction of the total fishing effort in this area. Thus in this case study we are only considering the demersal fisheries to gain a full understanding of the fisheries that mainly operate in this ecoregion.
In Discardless we focus on the French, Irish and British mixed demersal fisheries operating within the Celtic Sea area. The most important fishery in terms of landings is the French fishery (62% of landings for 2011-2014), followed by the UK with 20% of the landings for this period and then Ireland with 19% of the landings.
These fisheries consist of several fleets mainly comprising of bottom trawlers, but also including beam trawlers, gillnetters and longlines, using different métiers and targeting different species assemblages throughout the year. The main species caught are angler fish (Lophius piscatorius & budegassa), hake (Merluccius merluccius), haddock (Melanogrammus aeglefinus), whiting (Merlangius merlangus) and Norway lobster (Nephrops norvegicus). Two areas are important in terms of landings, south of Ireland (especially statistical rectangle 31E3) and south Cornwall in area VIIe (especially statistical rectangle 28E5).
The mixed nature of these fisheries leads to high discard ratios, especially in the mixed demersal trawl fishery where many species occupy similar habitats and display similar behaviours making it difficult to selectively fish for individual species. The most discarded quota species in the Celtic Sea include whiting (Merlangius merlangus), Atlantic mackerel (Scomber scombrus), hake (Merluccius merluccius), plaice (Pleuronectes platessa) and Norway lobster (Nephrops norvegicus).
Proportion of landings in each rectangle
Landings 2015
       [STECF FDI data (2015)] |
Trends in landings by gears
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[STECF FDI data (2015)] |
The demersal landings (in volume) are mainly made by bottom trawlers although there has been an increase in the landings made by gillnetters and longliners in the last couple of years. Commercial landings are highly structured in space, and the Celtic sea is characterised by several type of mixed fisheries. The bottom trawlers are fishing on a mix of demersal species and mainly land species subject to TACs including hake, haddock, whiting and anglerfish in the Central part of the Celtic sea and in the Channel. Area VIIe is characterized by a high diversity of gear including beamer (UK) and gillnetter implying diversity of landed species with the predominance of the other groups (which correspond to bivalves such as scallops and cephalopods mainly) and some gadoids patches south of Cornwall. Longliners and gillnetters target hake and monkfish along the continental slope.
There is also a spatial structure in effort per country; France is present in all areas whereas UK vessels are more focussed along the UK coast while Irish vessels concentrate around the Irish coast.
Data for France are absent from the STECF database prior to 2011.
Average Landings by gears
Year 2015
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[STECF FDI data (2015)] |
Average Landings by countries
Year 2015
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[STECF FDI data (2015)] |
Average Landings by species
Year 2015
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[STECF FDI data (2015)] |
Trends in landings by species
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[STECF FDI data (2015)] |
Discards
Discards figures are the estimates from STECF working group on Fisheries Dependent Information group. Their spatial reallocation was made proportional to the observed landings by métier and species. This might not be realistic/accurate for all species, however it allows a first approximation of the areas that might be of main concern, and starts the dialogue between scientists, fishermen and managers to better describe these areas.
Discards are described by gear and split between non TAC and TAC species, because only discards of TAC species would be subject to the landing obligation. We can see that in the channel, discards are quite high compared to the other areas but mainly composed of non TAC species such as gurnard, pouting and crab.
Catches (Landings+Discards)
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[STECF FDI data (2015)] |
Disclaimer : Following graphs are made using discards rates at high spatial level and the landings at statistical rectangle level as raising factor. We assume that it's not the more statistically consistent way to proceed. However we consider that, with available data, it's a first step to use the data.
Discards by species (Average discards ratio applied to landings by rectangle)
Year 2014
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[STECF FDI data (2015)] |
Year=2015
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[STECF FDI data (2015)] |
Discards by Species for most important gears (year=2015) (Average discards ratio applied to landings by rectangle)
First Gear (in terms of total discards) (TR1)
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[STECF FDI data (2015)] |
Discards by "on quotas" Species for most important gears (year=2015) (Average discards ratio applied to landings by rectangle)
First Gear (in terms of total discards) (TR2)
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[STECF FDI data (2015)] |
Trends in discards by Country (5 most important countries in Landings)
Total Discards
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[STECF FDI data (2015)] |
Discards ratio (Discards/(landings+discards))
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[STECF FDI data (2015)] |
Trends in discards by Gear (5 most important Gear in Landings)
Total Discards
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[STECF FDI data (2015)] |
Discards ratio (Discards/(landings+discards))
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[STECF FDI data (2015)] |
As in the areas other than the Celtic Sea, bottom trawlers have the higher discard ratios. The rate of discards by species has been relatively stable over the last few years. Discards composition varies between gears. Bottom trawlers discards of TAC species are mainly composed of whiting south of Ireland and a mix of mackerel and whiting in area VIIe. Gillnetters’ discards are mainly composed of hake along the continental slope and place south Cornwall. Many reasons for discarding have been identified and listed for these fisheries and are often associated with the problems of working in an area with a mixed species assemblage as well as being a consequence of minimal landing sizes, TACs limitation and market restriction acting on the fisheries.
Trends in discards by species (5 most important species in Landings)
Total Discards
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[STECF FDI data (2015)] |
Discards ratio (Discards/(landings+discards))
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[STECF FDI data (2015)] |
En savoir plus
Citation :
Fiche Celtic Sea, Author(s) : Marianne Robert and Julia Calderwood
DiscardLess Atlas [on line]. 2017. Guitton J., Ulrich, C., Vermard Y., Afonso P., Andonegi E., Argyrou I., Calderwood J., Fauconnet L., Quetglas A., Morato T., Prellezo R., Robert M., Savina-Rolland M., Triantaphyllidis G., Vaz S.
http://www.discardless.eu/atlas/
