Mackerel

What you're looking at

The Atlantic mackerel (Scomber scombrus) is the UK summer staple — beautifully streamlined, iridescent blue-green back with bold wavy black stripes, silver flanks fading to a polished white belly. They arrive in coastal waters from late spring and feed in roving shoals through to early autumn.

Key features

• Body: Perfectly torpedo-shaped — symmetrical, fast-water built. Designed for sustained pelagic cruising.
• Markings: Striking dark, wavy vertical bars on the upper half of the body, breaking up over the back. Iridescent blue, green and gold sheen over silver.
• Tail: Deeply forked, with the most reliable mackerel-family signature: a row of small "finlets" running between the second dorsal fin and the tail, and again between the anal fin and the tail.
• Dorsal fins: Two well-separated dorsals. Front is spiny, back is soft, followed by finlets.
• Lateral line: Inconspicuous, slightly wavy.
• Size: Most fish 0.3–0.7 kg; specimen at 1 kg; UK record over 2.7 kg.

Confusion species

• Spanish mackerel / chub mackerel: Very similar shape and finlets, but with rounder, broken spots on the flanks rather than vertical bars. Increasingly common in UK waters as the sea warms.
• Scad (horse mackerel): Distinct armoured scutes along the lateral line and a much harder body. Single visible dorsal fin appears taller and more pointed.
• Garfish: Long, eel-like body and a needle-pointed beak — easy to separate up close.

Where to find them

Beaches, piers, breakwaters, harbours and from boats off any open coast from May to October. They follow sand-eel and whitebait shoals, so look for diving gannets and gulls. A string of small feathered hooks worked through the upper water column is the classic technique. The flesh is oily and best eaten the day it's caught; bleed and chill fish immediately to keep them at their best.