Spurdog
Spurdog are small sharks — slim, sharp-snouted, and built for covering ground — that turn up along most of the UK coastline, with the western coasts of Scotland, England, and Ireland producing the most consistent sport.
After a stock collapse and years of strict commercial restrictions, populations have recovered enough that limited fishing resumed in 2023. For shore and boat anglers, they're a genuine target species with a conservation story worth knowing.
Scientific Name: Squalus acanthias
Also known as Spiny Dogfish, Piked Dogfish, Spiked Dogfish, Spurries, Rock Salmon, Flake
- Slim, grey to brown shark with a pale belly; some fish carry faint white spots along the flanks — a useful field mark against similar species.
- The single most reliable ID feature: a sharp, venomous spine on the leading edge of each dorsal fin. No other British shark has this. Handle with care — the spines can cause painful wounds and infection.
- No anal fin, and the pectoral fins are broad and triangular with no rays or segments — classic shark build but noticeably slender.
- Shore-caught fish typically run 5–10 lb; the UK shore record stands at 23 lb 2 oz. Maximum length around 124 cm.
What to know
Habitat Distribution
- Found in temperate waters around most of the UK, but most consistently encountered along the western coasts of Scotland, England, and Ireland.
- A highly migratory species that moves in shoals and can cover large distances quickly — fish tagged around the British Isles have been recaptured from waters all around the coast over multi-year periods.
- Primarily a demersal species, spending most time near the seabed, but will move into midwater when prey is available — particularly in summer when herring, sprats, and sandeels school near the surface.
- Tolerates a wide depth range: from relatively shallow inshore water (40 feet or less is common for shore-caught fish) down into deeper offshore grounds.
Key Locations
- Loch Etive, Argyll — one of the most consistently named shore marks for spurdog on Scotland's west coast, with fish taken year-round.
- Loch Sunart and Lochaline, Scottish Highlands — productive sea loch marks where shoals move through regularly and shore access is practical.
- Western coasts of Scotland generally — the west coast sea lochs and open coast marks produce the most reliable spurdog fishing in the UK.
- Cornish waters — significant commercial landings recorded here, and the mixed ground off Cornwall holds fish accessible to boat anglers.
Specific Spots
- Rocky ground and mixed seabed close inshore — spurdog follow prey into surprisingly shallow water, and a cast of 30–40 metres from shore is often enough on Scotland's west coast sea lochs.
- Kelp edges and reef margins where small fish concentrate; the sharks patrol these transitions looking for flatfish, codling, and sandeels.
- Deeper channel edges and drop-offs from a boat, where shoals move through on feeding runs — once you find one fish, others are usually close behind.
- Sea lochs on Scotland's west coast — Loch Etive, Loch Sunart, and Lochaline are among the most productive named marks for shore-caught spurdog.
Spurdog FAQ
Answers from onWater's species guide.
What are the best lures and bait for Spurdog?
Fresh mackerel, whole small fish, fillets, or chunks, is the standout bait across UK marks. Blueys (Pacific saury), sandeel, and squid are reliable alternatives and worth carrying as a change bait.
When is the best time to fish for Spurdog?
Year-round on Scotland's west coast sea lochs, where spurdog are a consistent target across all months. Summer and early autumn bring fish into shallower inshore water more reliably as shoaling prey species like herring and sandeels concentrate near the surface.
How do you catch Spurdog?
Most UK spurdog fishing is done from the shore on Scotland's west coast sea lochs, or from small boats over mixed and rocky ground. Anglers fish fresh fish baits on the bottom, often at night, and work marks methodically, once a shoal is located, multiple fish can follow in quick succession.
What do Spurdog eat?
Bottom-feeding fish make up the core of the diet, small flatfish like flounder and plaice, codling, and whiting. Fresh fish baits (mackerel, blueys, sandeel, squid) directly imitate this prey and are the go-to for UK anglers, with a plain chunk of mackerel widely regarded as the most reliable option.
Where do Spurdog live?
Found in temperate waters around most of the UK, but most consistently encountered along the western coasts of Scotland, England, and Ireland.
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