Minimum Conservation Reference Sizes (MCRS) in UK waters
Updated 3 February 2026
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1. Fish
| Species | Scientific name | MCRS in UK waters* |
|---|---|---|
| Anchovy | Engraulis encrasicolus | Whole area, except ICES division IXa east of longitude 7° 23′ 48″ W: 12 cm or 90 individuals/kg. ICES division IXa east of longitude 7° 23′ 48″ W:10cm |
| Bass | Dicentrarchus labrax | 42 cm (1) |
| Blue ling | Molva dipterygia | 70 cm |
| Brill | Scophthalmus rhombus | 30 cm (7d and 7e only) |
| Cod | Gadus morhua | 35 cm |
| Haddock | Melanogrammus aeglefinus | 30 cm |
| Hake | Merluccius merluccius | 27 cm |
| Herring | Clupea harengus | 20 cm |
| Horse mackerel | Trachurus spp. | 15 cm |
| Lemon Sole | Microstomus kitt | 25 cm (7d and 7e only) |
| Ling | Molva molva | 63 cm |
| Mackerel | Scomber spp. | Whole area, except North Sea: 20 cm. North Sea: 30 cm |
| Megrim | Lepidorhombus spp. | 20 cm |
| Plaice | Pleuronectes platessa | 27 cm |
| Pollack | Pollachius pollachius | 30 cm |
| Red Sea Bream | Pagellus bogaraveo | 33 cm (2) |
| Saithe (Coalfish) | Pollachius virens | 35 cm |
| Sardine | Sardina pilchardus | 11 cm |
| Sole | Solea spp. | 24 cm |
| Turbot | Scophthalmus maximus | 30 cm (7d and 7e only) |
| Whiting | Merlangius merlangus | 27 cm |
*Region 2 as defined by Council Regulation (EC) No 850/98 Article 2 1 (b)
(1) Commission Implementing Regulation (EU) 2015/1316
(2) Commission Implementing Regulation (EU) 2017/787
2. Molluscs
| Species | Scientific name | MCRS in UK waters* |
|---|---|---|
| Bean Solen** | Pharus legumen | 65 mm |
| Carpetshell** | Venerupis pullastra | 38 mm |
| Clam** | Venus verrucosa | 40 mm |
| Donax Clams** | Donax spp. | 25 mm |
| Grooved carpetshell** | Ruditapes decussatus | 40 mm |
| Hard Clam** | Callista chione | 6 cm |
| Octopus | Octopus Vulgaris | 750 grams |
| Queen scallop** | Chlamys spp. | 40 mm |
| Razor Clam** | Ensis spp | 10 cm |
| Scallop** | Pecten maximus | Whole area, except ICES VIIa north of 52o 30′ N and VIId: 100 mm ICES VIIa north of 52o 30′ N, VIId: 110 mm |
| Short-necked Clam** | Ruditapes Phillippinarum | 35 mm |
| Surf Clams** | Spisula solida | 25 mm |
| Whelk** | Buccinum undatum | 45 mm |
*Region 2 as defined by Council Regulation (EC) No 850/98 Article 2 1 (b)
**Must be landed whole
3. Crustaceans
| Species | Scientific name | MCRS in UK waters* |
|---|---|---|
| Crawfish** | Palinurus spp. | 110 mm |
| Deepwater Rose Shrimp | Parapenaeus longirostirs | 22 mm (carapace length) |
| Edible crab*** | Cancer pagarus | Regions 1 and 2 north of 56o N: 140 mm Region 2 south of 56o N, except ICES Divisions VIId, e, f, and ICES Divisions IVb, c: 130 mm ICES Divisions IVb, c south of 56 oN: 130 mm, except for an area limited by a point at 53o28′22″ N, 0o09′24″ E, on the coast of England, a straight line joining this point with 53o28′22″ N, 0o22′24″ E, the 6 mile boundary of the United Kingdom, and a straight line connecting a point at 51o54′06″ N, 1o30′30″ E, with a point on the coast of England at 51o55′48″ N, 1o17′00″ E, where the minimum landing conservation reference size shall be 115 mm ICES Divisions VIId, e, f: 140 mm Region 3: 130 mm In all English waters west of 2o.56.78W longitude and south of 52o 0N latitude, the minimum conservation reference size for Edible crab (Cancer Pagurus) is 150mm for female crabs and 160mm for male crabs. |
| Lobster** | Homarus gammarus | 87 mm |
| Norway lobster | Nephrops norvegicus | Whole area, except Region 3 and ICES VIa, VIIa: total length 85 mm, carapace length 25 mm, tail 46mm ICES VIa, VIIa; Region 3: total length 70 mm, carapace length 20 mm, tail 37mm |
| Norway lobster tails | Nephrops norvegicus | Whole area, except Region 3 and ICES VIa, VIIa: 46 mm ICES VIa, VIIa; Regione 3: 37 mm |
| Spinous Spider Crab** | Maia squinado | Male 130mm2 Female 120 mm |
| Velvet crab** | Necora puber | Whole area except Outer Hebrides and the Orkney Islands 65 mm. (3) Outer Hebrides and the Orkney Islands 70 mm. (3) |
*Region 2 as defined by Council Regulation (EC) No 850/98 Article 2 1 (b)
**Must be landed whole
***When using pots or creels, a maximum of 1 % by weight of the total catch of edible crabs landed may consist of detached claws. For all other gear types a maximum of 75kg of detached claws may be landed
(1) Statutory Instrument 2000/ 2029 The Undersized Edible Crabs Order 2000. Applies to UK vessels only
(2) Statutory Instrument 2000/1502 The Undersized Spider Crabs Order 2000. Applies to UK vessels only
(3) Statutory Instrument 1898/919 Undersized Velvet Crabs Order 1989. Applies to UK vessels only