Sea trout

Quick facts

How to identify it

At sea and fresh from the sea it is bright silver with a dark blue-green back and scattered black spots that extend well below the lateral line and onto the gill covers; in the river it darkens to bronze and brown, and spawning males grow a kype. Compared with an Atlantic salmon of the same size, the sea trout has a thicker tail wrist that can be held without slipping, a square rather than forked tail, more spots below the lateral line, and an upper jaw that reaches past the rear of the eye. Between the adipose fin and the lateral line it typically has 13–16 scales, against 10–13 in salmon.

Where it lives

Young sea trout spend one to three years in the river before smoltifying and dropping down to the sea, where they stay in coastal waters rather than crossing oceans. They hunt shallow inshore ground: sandy bays broken by weed and boulders, reefs, points, estuary mouths and shallow fjords, usually in 1–4 m of water and often within casting range of the shore. Mature fish return to the rivers of their birth from spring to autumn, holding in deep pools, under tree roots and along undercut banks by day and moving through the shallows at night. The species is native from Iceland, the British Isles and Scandinavia through the Baltic to the Atlantic coasts of France and Spain, and has been introduced elsewhere.

Season and behaviour

Sea trout spawn from October to January in the gravel of small tributaries and headwaters, when rivers and coasts are closed or restricted. On the coast the classic seasons are spring, from March to May, when hungry post-spawn fish move into warming shallows to feed, and autumn, from September to November, when bright fish gather off river mouths before running; on warm summer nights they feed close to shore after dark. In rivers the run follows the water: a summer flood brings a fresh wave of fish, and fish are most catchable in their first days and on dark, mild nights. River sea trout feed little and take a fly or lure out of aggression or reflex, so presentation and timing matter more than bait.

Fishing methods

Coastal spinning is the most accessible method: a slim 15–30 g casting lure or a bombarda float with a fly, cast long over shallow mixed bottom and retrieved at a steady, medium pace with pauses; wade quietly and cover water, because sea trout move constantly. Coastal fly fishing uses a single-handed rod with a floating or intermediate line and sparse shrimp, sandeel and small baitfish patterns fished on a slow strip. In rivers the night fly is the tradition: wet flies and small tubes swung across the pool tail after dark, and a surface lure skated over the pool when fish are lively. Spinning with spoons and minnow plugs works in coloured water after a flood, and where allowed a worm drifted through the pool takes running fish. Use a strong leader, and expect a fast, jumping fight that tests every knot.

Baits and lures

On the coast, imitate what the trout eat: shrimps, sandeels, sticklebacks, ragworms and small herring. Slim silver, copper and pink casting lures, small spoons and shrimp or sandeel flies in natural olives, tans and pinks are the standards, with dark or black flies on dark nights. In rivers, small dark wet flies, silver-bodied tubes and surface lures at night, silver or gold spoons and 5–9 cm minnow plugs by day in coloured water, and where permitted a lobworm on a single hook.

Tips from the bank

1. 01On the coast, fish the change of light and the first hours of darkness, and keep moving until you find fish — a hundred metres can be the difference.
2. 02Look for shallow mixed bottom with sand, weed and boulders next to slightly deeper water, and fish it on a rising tide or when the wind pushes water onto the shore.
3. 03In spring, start on the sheltered, sun-warmed shallows; in autumn, concentrate on the coast near river mouths.
4. 04In rivers, walk the pool in daylight to learn its lies, then fish it at night without a light on the water.
5. 05Cast a swung fly across the tail of the pool first, because that is where running fish rest.
6. 06The first flood after a dry spell is the best river night of the summer — fresh fish take boldly for a day or two.
7. 07Use a strong leader and a soft-actioned rod: sea trout jump and have soft mouths, and heavy-handed striking tears hooks out.

Where to catch Sea trout

Waters where Shoalmap's fishing reports list Sea trout.

• Hallingdalselve
• Narva jõgi - Narva

Related species

• Brown trout
  Salmo trutta

  The wary, spotted native of cold rivers and deep lakes.

• Atlantic salmon
  Salmo salar

  The king of fish — ocean-run silver returning to its home river.

• Rainbow trout
  Oncorhynchus mykiss

  The hard-fighting, high-jumping trout of stocked lakes and cool rivers.

• Arctic char
  Salvelinus alpinus

  The cold-water char of deep alpine lakes and Arctic rivers.

Frequently asked questions