Ray, Spotted

Raja montagui

Method of production — Caught at sea
Capture method — Demersal otter trawl
Capture area — North East Atlantic (FAO 27)
Stock area — West of Scotland and Southwest Ireland
Stock detail — 6, 7b,j
Picture of Ray, Spotted

Sustainability rating five info

Sustainability overview

The stock status of spotted rays in this area is generally unknown but indicators show that the populations has been increasing since 2008, followed by a slight decline in since 2017. There is concern for fishing mortality as landings have been higher than those recommended in scientific advice.

The landing obligation will be fully in place in 2019, which requires that all species with catch limits should be retained. However, skate and rays are exempt from the landing obligation due to their assumed high discard survival rates. There is no specific management plan for skates and rays in these waters. They are managed under a total allowable catch (TAC) for many skates and rays but greater protection is needed. Further management of the species is advised e.g. through fishery closures to allow them to reproduce.

. Demersal otter trawling is associated with discarding of unwanted fish and sometimes catch Endangered, Threatened and Protected species but capture rates can be reduced with appropriate gear modifications.

Biology

Spotted rays belong to the Rajidae family which includes skates and rays. Spotted rays are a small to medium sized inshore and coastal shelf species attaining a maximum length of 80cm and weight of 4kg. Males mature at a length of about 54cm and females at about 57cm (both between 3 to 8 years old). The species has a maximum recorded age of 14 years. Female Spotted rays lay their egg cases in shallow water in early summer from April through to July.

Stock information

Criterion score: 0.75 info

Stock Area

West of Scotland and Southwest Ireland

Stock information

There are no reference points for this spotted ray stock and therefore, it is unknown if the stock is overfished. However, the stock size indicator has been increasing since 2008, but there have been slight declines in last year (ICES 2018). Therefore, there is no concern for biomass.

It is unknown if spotted rays are undergoing overfishing, though in 2017, ICES species-specific landings minimum estimate based on reported landings was 96 tonnes whilst the landings corresponding to advice 67 tonnes (ICES 2018). Therefore, there is concern for fishing mortality as landings are larger than those advised. Low Resilience.

Management

Criterion score: 0.75 info

There is no direct management plan for skates and rays in these waters. They are usually caught as bycatch in otter and beam trawl fisheries, which target finfish (including flatfish and gadoids).

Skates and rays are managed under five regional quotas (called TACs) which are applied to a group of species, rather than individual skate and ray species. This has been deemed as an unsuitable method for protecting individual species, but species-specific quotas may increase discarding.

The European Commission have considered that skates and rays caught in the Northwest waters (ICES subareas 6 and 7) with all fishing gears, should be exempt from the landing obligation, based on their assumed high survivability rates. However, Member States harvesting the stocks should supply data to STECF to review the effectiveness of the exception and, by the 31 May each year produce a roadmap to increase survivability, fill in the data gaps identified by STECF and produce annual reports on the progress on survivability programmes. Any skates and rays that are discarded are required to be released immediately and below the sea surface. Any vessels fishing using bottom trawls or seines, with catches comprising more than 10% of haddock, cod and skates and rays combined, are required to use, either a) a 120 mm cod-end, or b) an eliminator trawl with 600 mm large mesh panels and a 100 mm cod-end. For vessels fishing using bottom trawls or seines with catches comprising less than 10% of haddock, cod and skates and rays combined, vessels are required to use a cod-end mesh size of 100 mm with a 100 mm squared mesh panel, except for vessels with catches comprising over 30% of Norway lobster. (European Commission 2018b).

Other management methods are currently being considered at an EU level, fishing gear modifications, education, conservation measures (such as closed seasons during spawning times). Some protected areas have been designated in these waters but offshore areas are not sufficiently managed. There are no official minimum landing sizes except for some IFCAs, which, mandate a minimum landing size (40-45 cm disc width) in inshore waters in England and Wales.

Monitoring
ICES conduct assessments for most skate and ray species on a biennial basis. There are a lack of reference points for the stock, which prevents the development of management plans (Mangi et al. 2018). Data-limited approaches have been used (using some survey and landings data) but there are important information gaps. Projects including the Fisheries Science Partnership, Sustainable Management of rays and Skates (SUMARiS), National Evaluation of Populations of Threatened and Uncertain Elasmobranch Stocks (NEPTUNE) have been collecting data to close these data gaps. Fishery-independent data are collected on the stock, primarily through the Irish groundfish survey, which is considered to have an appropriate level of coverage of the stock. Data have been collected through this survey generally since 2003. Fishery-dependent data have also been collected on the stock, particularly landings data, which have improved in quality over recent years, however, commercial landings data still contains inaccuracies, as spotted ray can be confused with the blonde rays (ICES 2018).

Enforcement
Surveillance legislation is underpinned by EU Law, which require that all vessels above 12m in length use vessel monitoring systems (VMS), and mandate at-sea and aerial surveillance and inspections of vessels, logbooks and sales documents. There is direct management of fishing effort for vessels since 2003, which allocates effort in kW-days to vessels of >15 m. However, the inshore (smaller) fleets are generally not managed by effort to the same extent.

Capture Information

Criterion score: 0.5 info

Spotted rays are a shelf species. They are often caught as bycatch in trawl and gillnet fisheries, particularly in mixed demersal fisheries which retain groundfish or species of the skate complex. The spotted rays are one of the smaller and less valuable species found in the skate complex and are often discarded (ICES 2018).

Bycatch
There is a lack of information available on other bycatch species but in the southern North sea, common bycatch in bottom trawls include mixed crabs, urchins, lesser spotted dogfish, nursehound, dragonet, starry ray, smelt. Endangered, Threatened and Protected (ETP) species including Angel shark and Common skate (both critically endangered (IUCN)) which were depleted through fishing in this area. Invertebrates such as crabs and urchins are vulnerable to damage.

Discards
The landing obligation will be fully implemented into our seas from 2019. Skates and rays will be exempt from the landing obligation, due to their higher likelihood of survival when discarded. Member states will be required to report on skate and ray catches and discards, and any improvements in selectivity programmes. it’s difficult to avoid catching skates and rays in nets and because of their peculiar shape and size; it’s also difficult for them to escape the net once captured. Therefore, selectivity programmes are in place reduce skate and rays catches and their survival rates. Discard rates of skates and rays vary dramatically (30 - 70%), depending on the marketability and management measures in place. For example, nearly all skates below 30 cm LT are discarded by English vessels (Silva et al., 2012). Bycatch can include juvenile skate as they can hatch from their egg cases at sizes of 10-20 cm LT and therefore, may be able to escape through the nets (Ellis et al. 2018). Their survival rates upon discarding is extremely variable, depending on the fishing and handling methods used to capture them. Elasmobranchs have the potential for relatively high survival rates because they do not have swim bladders (and thereby are not as impacted by pressure changes), they can have thick and abrasive skins and thorns (which protect them) and some have spiracles and a buccal-pump respiratory which excrete a mucus, which allows the skate or ray to ventilate and acquire oxygen when out of the water (Ellis et al. 2018). Inshore and coastal fisheries using trawls, longlines, gillnets and tangle nets generally show low at-vessel mortality. There are a lack of studies available on long-term skate and ray survival when they are released into the wild (Ellis et al. 2018).

Habitat
Bottom trawling has the potential to cause significant impact to habitat, such as removing or destroying physical features and reducing biota and habitat complexity. Therefore, the recovery time of the seabed after trawling varies greatly, and depends on the fishing gear, the substrate, intensity of the trawl and how accustomed the seabed is to natural disturbance.

Spotted rays are generally found in depths of 30-150 m in sandy substrates (Dedman et al. 2017).

Alternatives

Based on method of production, fish type, and consumer rating: only fish rated 2 and below are included as an alternative in the list below. Click on a name to show the sustainable options available.

Dab
Halibut, Atlantic (Farmed)
Halibut, Pacific
Megrim
Plaice
Sole, Dover sole, Common sole
Sole, Lemon
Turbot (Caught at sea)
Turbot (Farmed)

References

ICES. 2018. Spotted ray (Raja montagui) in Subarea 6 and divisions 7.b and 7.j (West of Scotland, west and southwest of Ireland). Available at: http://ices.dk/sites/pub/Publication%20Reports/Advice/2018/2018/rjm.27.67bj.pdf ; Dedman, S., Officer, R. Brophy, D., Clarke, M. Reid, D. G. 2017. Towards a flexible Decision Support Tool for MSY-based Marine Protected Area design for skates and rays, ICES, 74 (2) pp. 576-587, https://doi.org/10.1093/icesjms/fsw147

Ellis, J. R., Burt, G.J., Grilli, G., McCully Phillips, S.R., Catchpole, T.L., Maxwell, D.L. 2018. At-vessel mortality of skates (Rajidae) taken in coastal fisheries and evidence of longer-term survival. Journal of Fish Biology. 92, 1702-1719. doi:10.1111/jfb.13597

Mangi, S., Kupschus, S., Mackinson, S., Rodmell, D., Lee, A., Bourke, E., Rossiter, T., Masters, J., Hetherington, S., Catchpole, T. and Righton, D. 2018. Progress in designing and delivering effective fishing industry science data collection in the UK. Fish 00:1-21. https://doi.org/10.1111/faf.12279

Shephard, S. Reid, D.G.,Gerritsen, H.D, Farnsworth, K.D. Estimating biomass, fishing mortality, and total allowable discards for surveyed non-target fish, ICES Journal of Marine Science, Volume 72, Issue 2, 1 January 2015, Pages 458-466, https://doi.org/10.1093/icesjms/fsu146