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Common Skate, Blue Skate, Grey Skate, Pocheteau Gris (Fr), Noriega 
(Es).

Common Skate

Dipturus batis

Raja batis (Linnaeus, 1758), Raja macrorhynchus (Rafinesque, 1810), 
Raja flossada (Risso, 1826), Raja intermedia (Parnell, 1837), Laeviraja 
macrorhynchus (Bonaparte, 1839).

COMMON NAMES

•  Large, up to 285cm total length.
•  Long, pointed snout.
•  Upper surface olive-grey to brown.
•  Variable pattern of light spots and dark blotches.
•  Lower surface black in juveniles, fading with age.
•  Juveniles have large orbital thorns.

The Common Skate has a long and pointed snout giving the disc a 
broadly rhombic shape with the front margins distinctly concave. 
The dorsal surface of the disc is olive-grey or brown with a variable 
pattern of light spots and dusky blotches. In sub-adults there is often 
a marking on each pectoral fin resembling an eye spot (Whitehead et 
al., 1986). The ventral surface of the disc is black in juveniles and fades 
to grey as the animal matures (Neal et al., 2008). The mucus pores on 
both sides of the disc are marked with black spots and short streaks 
which are particularly numerous on the lower surface (Whitehead et 
al., 1986).

Juveniles are smooth on both surfaces of the disc but often have 

large orbital thorns. Adults are partly prickly on both the upper and 
lower surfaces but have no thorns on the disc. There are two rows of 
12-18 thorns along the tail (measured from the cloaca) and normally 
one or two thorns between the dorsal fins. Often there are thorns 
along the lower edges of the tail, particularly so in females (Luna, 
2009).

They are the largest skate found in European waters with females 

reaching a maximum total length of 285cm. They have between 40 
and 56 rows of teeth and may live for 50-100 years (Luna, 2009; Dulvy 
et al., 2006; Neal et al., 2008).

The Common Skate was historically found across much of the 
northeast Atlantic and Mediterranean (Luna, 2009). Its range has 
been greatly reduced due to fishing pressure and it is now almost 

SYNONYMS

DISTRIBUTION

APPEARANCE

No Records
Occasional
Range

Map base conforms with ICES grid squares.

extinct in the 
Mediterranean 
(Abdulla, 2004). 
Around the UK, 
individuals are 
occasionally 
reported from the 
Irish Sea, Bristol 
Channel and central 
North Sea but it 
would appear that 
its range is now 
effectively limited to 
northwest Scotland 
and the Celtic Sea. 
(Dulvy et al., 2006).

N

AT

M

ED

CR

RJ

B

Dorsal View (

♀)

Ventral View (

♀)

Text & Illustrations © Shark Trust 2009

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SIMILAR SPECIES

Dipturus nidarosiensis, Black Skate 
Dipturus oxyrinchus, Long-nosed Skate 
Rostroraja alba, White Skate

 

Common Skate

Dipturus oxyrinchus, 
Long-nosed Skate

Dipturus nidarosiensis, 
Black Skate

Rostroraja alba, 
White Skate

Text & Illustrations © Shark Trust 2009

Supported by:

(Not to scale)

Dipturus batis, 
Common Skate

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Common Skate

Dipturus batis

TEETH

There are between 40–56 rows of 
teeth (Luna, 2009).

HABITAT

Like most skates and rays, the Common Skate is a bottom 
dwelling species that is found from coastal waters to a depth of 
approximately 600m (1,970ft), although it is most commonly found 
around 200m (670ft) (Dulvy et al., 2006). Unlike most other skate, it 
is active both day and night (Luna, 2009).

ECOLOGY & BIOLOGY

DIET

The Common Skate has been recorded as feeding on several species 
of skate (Raja spp.), dogfish (Squalus spp.), catshark (Scyliorhinus 
spp.), anglerfish (Lophius spp.), gurnards (Dactyloptena spp.), 
flatfishes, pilchards, herring (Clupea spp.) and scad (Trachurus spp.). 
Lobsters, crabs and cephalopods (particular Eledone spp.) are also 
important (Wheeler, 1969). It hunts actively, enveloping prey before 
consuming it (Dulvy et al., 2006). Mid-water species are captured by 
the skate propelling itself rapidly upward, enveloping and gripping 
the fish before returning to the seabed to consume it (Wheeler, 
1969). 

REPRODUCTION

The Common Skate takes around 11 years to reach sexual maturity 
at a length of around 150cm for males and 180cm for females. 
Females only breed every other year, mating in spring and laying 
up to 40 eggcases during summer which are deposited in sandy or 
muddy flats (Neal et al., 2008). These eggcases are large, measuring 
up to 25cm long (excluding the horns) and 15cm wide and are 
covered with close-felted fibres (Neal et al., 2008; Dulvy et al., 
2006). They have been reported as being loose on the seabed and 
occasionally secured between rocks. The embryos take between 2–5 
months to develop depending on temperature and the juveniles are 
born measuring 21-22cm long (Neal et al., 2008; Clark, 1926).

EGGCASE

1. Very large, 120–250mm in length (Neal et al., 2008).
2. Distinct lateral keels.
3. Very deep anterior fields (Luna, 2009).
Similar eggcase to the Long-nosed Skate, Dipturus oxyrinchus.

(Eggcase shown half actual size)

Text & Illustrations © Shark Trust 2009

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COMMERCIAL IMPORTANCE

Historically important, the Common Skate has been targeted across 
its range wherever and whenever it has been abundant. This has 
lead to serious declines in stocks making it a financially unsound 
species to target commercially. Until recently it was still caught 
and landed by multispecies trawl fisheries operating over the vast 
majority of its habitat (Dulvy et al., 2006). From January 2009 there 
has been a prohibition on commercial fishers retaining this species 
in ICES areas IIa, IIIa, IV, VI, VII, VIII & IX.

The Common Skate is a popular species with recreational 

anglers due to its large size but if these fish are returned alive there 
is a good chance of them surviving (Catchpole et al., 2007). A catch 
and release scheme involving recreational anglers in the Sound of 
Mull, Scotland, generates an estimated £1,000,000 a year from a 
stock of around 500 fish (Holt, 2005).

IUCN RED LIST ASSESSMENT

Critically Endangered (2006).
Critically Endangered in northeast Atlantic.

THREATS, CONSERVATION, LEGISLATION

The large size of the Common Skate allows it to be caught by most 
fishing gear from birth, giving individuals little or no chance to 
reach maturity in heavily fished areas (UK Biodiversity Action Plan; 
1999). Combined with relatively late maturity and low population 
increase rates, the Common Skate is extremely vulnerable to fishing 
pressure. This has been seen in a drastic decline in populations 
during the 20th century, particularly around the UK. It has been 
extirpated from the majority of British coastal waters and is now 
only regularly found in northwest Scotland, the Shetlands and the 
Celtic Sea. French landings appear to be stable but this is likely to be 
due to a redirection of the fishing effort from the continental shelf 
into deeper water where the population may currently be stable 
(Dulvy et al., 2006). 

In 1999, the Common Skate was included on the UK Biodiversity 

Action Plan (BAP) list. Though this does not provide any legal 
protection for the species in itself, it includes provisions to work 
towards European conservation legislation. Its main targets 
included plans to stabilise populations in refuge areas by 2004 and 
to facilitate the migration of animals from refuge populations to 
areas where they are scarce or extinct (UK Biodiversity Action Plan; 
1999). 

In 2009, the Common Skate received protection from the 

European Council in ICES areas IIa, IIIa, IV, VIIa-k, VIII and IX, meaning 
that it cannot be retained by commercial fishers if captured. As 
elasmobranchs have no swim bladder that can overinflate or 
rupture, they are more likely to survive capture and release than 
teleost fish (DEFRA; 2008). The mandatory release order is therefore 
likely to significantly reduce the level of fishing mortality.

The vast majority of recreational anglers in the UK return any 

Common Skate they catch alive. Some angling clubs and the 
majority of charter boats tag and release Common Skate when 
caught, an activity which provides a sustainable source of income 
for many communities (Holt, 2005).

HANDLING AND THORN ARRANGEMENT

•  Handle with care.
•  Strong rows of thorns on midline.
•  Thorns between dorsal fins.

 

Common Skate

Text & Illustrations © Shark Trust 2009

Supported by:

TAXONOMIC NOTE

Since this factsheet was produced, genetic research has 

revealed that the Common Skate, Dipturus batis, is in fact two 
distinct species. These have been named D. intermedia and D. 
flossada. Common names already in use for these species are the 
Flapper Skate and Blue Skate respectively, although it remains to 
be seen if these become widely accepted.

The two species appear to have different distributions and 

biological characteristics. Of the two, D. intermedia is slower 
growing and reaches a larger size.  The first data published 
suggests a size at 50% maturity of 197.5cm (

♀) and 185.5cm (♂) 

for D. intermedia, compared to 122.9cm (

♀) and 115cm (♂) for D. 

flossada.  The largest positively identified specimen  of D. flossada 
was 143.2cm in length. It seems the maximum total length of 
285cm previously attributed to D. batis must be D. intermedia.

While the ranges of the species overlap it appears that D. 

intermedia is limited to west Scotland and west Ireland, with D. 
flossada limted to the southern Irish and Celtic Seas and the Rockall 
Trough. This appears to be closely related to temperature.

The most reliable means of distinguishing these species seems 

to be the colour of the iris.  In D. intermedia it is dark green/olive, in 
D. flossada it is pale yellow. Other morphometric features to check 
are the malar thorns, lateral tail thorns, interdorsal space and tooth 
bases. Colouration can differ on the ventral surface and on the 
centre of the wings. For a full discussion of these differences see 
Iglésias et al., 2009, available online.

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ABDULLA, A. 2004. Status and Conservation of Sharks in the 

Mediterranean Sea. IUCN Global Marine Programme. 

CATCHPOLE, T. L., ENEVER, R., DORAN, S. 2007. Programme 21: 

Bristol Channel Ray Survival. CEFAS. Lowestoft, UK. 

CLARK, R. S. 1926. Rays and Skates. A Revision of the European 

Species. Fishery Board for Scotland. HM Stationary Office. 
Edinburgh, UK.

DEFRA. 2008. Impact Assessment of Tope Shark Protection 

Measures. www.defra.gov.uk.

DULVY, N. K., NOTOBARTOLO DI SCIARA, G., SERENA, F., TINTI, F., 

UNGARO, N., MANCUSI, C., ELLIS, J. 2006. Dipturus batis. In: 
IUCN 2008. 2008 IUCN Red List of Threatened Species. www.
iucnredlist.org.

HOLT, D. 2005 Common Skate Tagging Programme. The Scottish 

Angling Homepage: www.catchalot.co.uk.

IGLÉSIAS, S. P., TOULHOAT, L., SELLOS, D. Y. 2009. Taxonomic 

confusion and market mislabelling of threatened skates: 
important consequences for their conservation status. Aquatic 
Conserv: Mar. Freshw. Ecosyst. Published Online 2009.

LUNA, S. M. 2009. Dipturus batis. Blue Skate. Fishbase. www.

fishbase.org.

NEAL, K. J., PIZZOLLA, P. F., WILDING, C. M. 2008. Dipturus batis. 

Common Skate. Marine Life Information Network: Biology 
and Sensitivity Key Information Sub-programme [on-line]. 
Plymouth: Marine Biological Association of the United 
Kingdom. www.marlin.ac.uk.

UK BIODIVERSITY ACTION PLAN. 1999. Species Action Plan: 

Common Skate (Dipturus batis). www.ukbap.org.uk.

WHEELER, A. 1969. The Fishes of the British Isles and North-West 

Europe. Macmillan and Co Ltd. London, UK.

WHITEHEAD, P. J. P., BAUCHOT, M. L., HUREAU, J. C., NIELSEN, J., 

REFERENCES

Common Skate

Dipturus batis

Text: Richard Hurst.
Illustrations: Marc Dando.

Citation
Shark Trust; 2009. An Illustrated Compendium of Sharks, Skates, Rays 
and Chimaera. Chapter 1: The British Isles. Part 1: Skates and Rays.

Any ammendments or corrections, please contact:
The Shark Trust
4 Creykes Court, The Millfields
Plymouth, Devon PL1 3JB

Tel: 01752 672008/672020

Email: enquiries@sharktrust.org

For more ID materials visit www.sharktrust.org/ID.

Registered Company No. 3396164.
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Text & Illustrations © Shark Trust 2009