Denmark country information

Common names: Sømrokke
Occurrence: native
Salinity: marine
Abundance: fairly common (chances are about 50%) | Ref: Winkler, H.M., K. Skora, R. Repecka, M. Ploks, A. Neelov, L. Urho, A. Gushin and H. Jespersen, 2000
Importance: | Ref:
Aquaculture: | Ref:
Regulations: | Ref:
Uses: no uses
Comments: Common in the North Sea and Kattegat (Ref. 9900). Also Ref. 4645.
National Checklist:
Country Information: https://www.cia.gov/library/publications/resources/the-world-factbook/geos/da.html
National Fisheries Authority:
Occurrences: Occurrences Point map
Main Ref: Muus, B.J. and P. Dahlstrøm, 1989
National Database:

Common names from other countries

Raie bouclée, Raya de clavos, Лисица морская (=скат колючий), ... more

Classification / Names Common names | Synonyms | Catalog of Fishes(genus, species) | ITIS | CoL | WoRMS | Cloffa

Elasmobranchii (sharks and rays) > Rajiformes (Skates and rays) > Rajidae (Skates)
Etymology: Raja: Latin, raja, -ae = a sting ray (Raja sp.) (Ref. 45335).
More on author: Linnaeus.

Environment: milieu / climate zone / depth range / distribution range Ecology

Marine; demersal; depth range 5 - 1020 m (Ref. 114953). Subtropical; 70°N - 38°S, 25°W - 50°E

Distribution Countries | FAO areas | Ecosystems | Occurrences | Point map | Introductions | Faunafri

Eastern Atlantic and Southwest Indian Ocean: Iceland to Madagascar, including the Mediterranean Sea.

Length at first maturity / Size / Weight / Age

Maturity: L_m 76.6, range 47 - 87.5 cm
Max length : 105 cm TL male/unsexed; (Ref. 53748); 139.0 cm TL (female); common length : 85.0 cm TL male/unsexed; (Ref. 9987); max. published weight: 18.0 kg (Ref. 35388); max. reported age: 15 years (Ref. 41305)

Short description Identification keys | Morphology | Morphometrics

Dorsal spines (total): 0; Anal spines: 0. Sub-rhomboid in shape with pointed wing-tips; disc-width 1,25 to 1,36 times in its length, its length 1,70 to 1,83 times in total length. Short rostrum, rounded at his extremity; pectoral fins with clear angles on lateral side; triangular pelvic fins (Ref. 39246). Dorsally prickly; large females also prickly throughout their ventral surface; juveniles and large males prickly along the margins of their discs and the underside of their snout. 30-50 thorns form a median row from the nape to the first dorsal fin; additional large 'buckler' thorns with swollen bases scattered on upper surface of disc in adults (Ref. 3167). Coloration is highly variable, with the dorsal surface having all shades of brown with dark and light spots and blotches; ventral surface white (Ref. 3167, 58137).

Inhabits shelf and upper slope waters. Reported depth ranges varies, from 10-300 m (Ref. 4426, 82319, 88187), and from 300-577 m in the eastern Ionian Sea (Ref. 56504); most common in coastal waters between 10-60 m depth (Ref. 58137). Tolerates low salinities (Ref. 88171). Found on mud, sand and gravel bottoms, rarely on rougher bottoms (Ref. 6808, 58137). Nocturnal species. Feeds on all kinds of bottom animals, preferably crustaceans (Ref. 3167) and fishes (Ref. 114953). Undertakes migrations with mean distances of 54-117 km per month; shows a clear annual migration cycle (Ref. 89017, 89018), moves from deeper offshore waters (10-30 m) in autumn and winter to shallower areas (<10 m) in spring (Ref. 82319). Young are non-migratory, inhabiting inshore nursery grounds (Ref. 89019, 89020, 89022); in the Bay of Douarnenez (France) they are found to remain in shallow waters for at least 2 years (Ref. 89023). Maturity age 7-8 years (Ref. 114953). Oviparous. Young may tend to follow large objects, such as their mother (Ref. 205). Detects weak electric fields generated by other organisms (prey detection and predator avoidance) but may also generate its own weak electric fields (Ref. 10311, 88171). Utilized fresh and frozen (Ref. 9987).

Life cycle and mating behavior Maturities | Reproduction | Spawnings | Egg(s) | Fecundities | Larvae

Oviparous. Distinct pairing with embrace. Polyandrous species (Ref. 89024). Paired eggs are laid and deposited on shallow sand, mud, pebble or gravel bottoms (Ref. 205, 89025). Up to 170 egg cases can be laid by a single female in a year (Ref. 3167), but average fecundity is much lower (around 48-74 eggs) (Ref. 3603, 31302). In northwestern Europe, egg cases are laid during spring (Ref. 3167) and in the Mediterranean during winter and spring (Ref. 3167). Egg cases are oblong capsules with stiff pointed horns at the corners, each containing one embryo (Ref. 205). Capsules are 5.0-9.0 cm long without the horns (Ref. 41250, 88187) and 3.4-6.8 cm wide (Ref. 41250). Egg cases are anchored with an adhesive film (Ref. 82399). Embryos feed solely on yolk (Ref. 50449). Egg cases hatch after about 4-5 months and pups are about 11-13 cm TL (Ref. 88864). Mating season from February to September, peaking in June (Ref. 74501). Adults observed to form same-sex aggregations during the mating season with females moving to shallower inshore waters approximately a month before the males (Ref 3603, 58137, 74501). Mating does not occur in the Baltic Sea (Ref. 82311).

Main reference Upload your references | References | Coordinator : McEachran, John | Collaborators

McEachran, J.D. and K.A. Dunn, 1998. Phylogenetic analysis of skates, a morphologically conservative clade of elasmobranchs (Chondrichthyes: Rajidae). Copeia 1998(2):271-290. (Ref. 27314)

IUCN Red List Status (Ref. 130435)

Near Threatened (NT) ; Date assessed: 03 October 2005

CITES (Ref. 128078)

Not Evaluated

CMS (Ref. 116361)

Not Evaluated

Threat to humans

Harmless

Human uses

Fisheries: commercial; gamefish: yes

FAO(Fisheries: production; publication : search) | FishSource | Sea Around Us

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Estimates based on models

Preferred temperature (Ref. 115969): 7.1 - 15.8, mean 10.7 (based on 474 cells).

Phylogenetic diversity index (Ref. 82804): PD₅₀ = 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].

Bayesian length-weight: a=0.00200 (0.00175 - 0.00228), b=3.26 (3.23 - 3.29), in cm Total Length, based on LWR estimates for this species (Ref. 93245).

Trophic level (Ref. 69278): 3.8 ±0.2 se; based on diet studies.

Resilience (Ref. 120179): Low, minimum population doubling time 4.5 - 14 years (K=0.09-0.14; tm=10; tmax=23; Fec=150).

Prior r = 0.18, 95% CL = 0.12 - 0.26, Based on 4 full stock assessments.

Fishing Vulnerability (Ref. 59153): High vulnerability (60 of 100).

Climate Vulnerability (Ref. 125649): High vulnerability (60 of 100).

Price category (Ref. 80766): Medium.

Raja clavata Linnaeus, 1758