Haddock
Haddock are a deep-water boat species that once ran in large numbers along Ireland's northern coasts but have been heavily reduced by commercial fishing pressure.
Today, the realistic targets are the offshore grounds off Cork — particularly around Union Hall and Castletownbere — and the Clare coast. A boat trip is almost always required; shore catches are rare.
Scientific Name: Melanogrammus aeglefinus
Also known as Cadóg
- Cream-white belly fading to silver-bronze flanks and a darker back; the dark, uninterrupted lateral line curves upward toward the head — the quickest field mark.
- A distinctive dark thumbprint blotch sits just above each pectoral fin; no other common Irish gadoid carries this mark.
- Three dorsal fins, the first tall and sharply triangular (pointed, not rounded like cod's); slightly forked tail.
- Most boat-caught fish run 1–2 kg; the Irish record is 5.39 kg, taken at Union Hall in 2010. Specimen weight is set at 2.5 kg.
What to know
Habitat Distribution
- A native North Atlantic species found throughout Irish and British waters, with a historical concentration along the north coast — Donegal, North Antrim, and the Causeway Bank — though those northern stocks have collapsed under commercial pressure.
- Remaining angling opportunities are concentrated on the southern offshore grounds: Cork (Union Hall, Castletownbere), Clare (Carrigaholt), and occasionally Donegal (Kincasslagh, Downings).
- A demersal, shoaling fish that favours mixed broken ground — reef patches interspersed with sand or gravel — at depths of roughly 40–300 m; bigger fish tend to sit over rougher, higher-rising reef.
- Also found around scattered wreck debris fields, particularly on the down-tide side where food concentrates.
Key Locations
- Union Hall, Co. Cork — produced the Irish record fish and remains one of the most reliable offshore haddock marks in the country.
- Castletownbere, Co. Cork — deep offshore grounds here hold haddock and are regularly worked by charter boats.
- Carrigaholt, Co. Clare — Clare coast charter boats report consistent haddock on the offshore grounds.
- Kincasslagh and Downings, Co. Donegal — historically productive northern marks; fish are now scarce but occasional specimens still appear.
- Causeway Bank, Portrush — once the most famous haddock mark in Ireland with regular specimens; stocks have all but disappeared.
Specific Spots
- Mixed reef-and-sand ground is the key habitat: haddock work the clean patches between rough structure, feeding close to the bottom but requiring bait presented just off the seabed rather than hard on it.
- Larger fish favour the steeper, rougher reef edges that drop away into broken ground — the transition zone between hard and soft bottom concentrates them.
- Scattered wreck debris fields hold groups of better fish, especially on the down-tide side where current pushes food across the bottom.
- In deeper channels off the Clare and Cork coasts, tighter schools form; a steady retrieve from depth is needed to keep fish from inflating their swim bladders on the way up.
Haddock FAQ
Answers from onWater's species guide.
What are the best lures and bait for Haddock?
Fish baits are the standard: mackerel strip, whole or half sandeel, and herring fillet cover most situations; fresh bait consistently outperforms frozen when available.
When is the best time to fish for Haddock?
Spring and early summer (April–June), one of the most frequently reported windows on the Cork and Clare grounds; fish are accessible and shoals are relatively predictable.
How do you catch Haddock?
Haddock in Ireland are almost exclusively a boat species, fished from charter or private vessels over mixed reef-and-sand ground offshore. Anglers work the bottom with natural baits on flowing traces, keeping the bait just above the seabed. The southern Cork and Clare grounds are the most productive options today.
What do Haddock eat?
Bottom-dwelling invertebrates, worms, shellfish such as mussels and scallops, and small crustaceans, make up a large part of the diet; ragworm and lugworm are consistently effective baits that directly imitate this forage.
Where do Haddock live?
A native North Atlantic species found throughout Irish and British waters, with a historical concentration along the north coast, Donegal, North Antrim, and the Causeway Bank, though those northern stocks have collapsed under commercial pressure.
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