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Sea trout
Sea trout (Salmo trutta trutta), The same Baltic fatty-fish reasoning as salmon; heavily protected as a fish.. The national eating advice, why it applies, the rules that matter when you catch it, and what the kitchen changes about the numbers.
Protected in a large part of Finland's inland waters — a wild fish there must be released.
Where it lives
The coastal fish of the winter fly angler: sea trout feed along shallow shorelines all year, including under cold conditions when nothing else moves, and run up small streams — some of them barely worth the name — to spawn in autumn. Estonia, Finland, Latvia and Sweden all have restoration programmes on those streams, because the limiting factor is almost never the sea, it is a culvert or a mill dam eight kilometres inland.
Why the advice says what it says
A sea trout is the same kind of fish as a Baltic salmon for contaminant purposes: fatty, feeding in the Baltic, and living long enough to accumulate. Sweden's advice names trout from the Baltic and from the two great lakes in the same sentence as herring and wild salmon. What makes sea trout distinctive is the regulatory weight rather than the contaminant one. Wild trout stocks in this region are fragile enough that whole categories of fish are simply off limits: in a large part of Finland inland migratory brown trout is protected outright and must be released, hatchery fish are marked by a clipped adipose fin so that a wild fish can be identified and let go, and spawning-coloured fish are protected in most rivers in the autumn. If you fish for sea trout, identification is a legal skill, not a hobby: you need to tell trout from salmon, wild from stocked, and a coloured spawner from a clean silver fish.
The advice
| Who it applies to | What the advice says | Where it comes from |
|---|---|---|
| People who are or may become pregnant | Sweden's advice puts trout from the Baltic, Vänern and Vättern in the same restricted group as Baltic herring and wild salmon: two to three times a year. | Swedish Food Agency (Livsmedelsverket) |
| Children and young people | Treat a large Baltic sea trout the way the advice treats Baltic salmon rather than the way it treats a farmed fish. | Reasoning from the shared fat and feeding pattern above |
| Everyone | Most sea trout caught by anglers here is released, which makes this the rare page where the eating question is often moot. | Regional catch-and-release practice |
The rules
What the rule book says about this fish, described by instrument rather than printed as a number:
- Migratory brown trout is fully protected in a large part of Finland's inland waters — the fish must be released, whatever its size.
- The adipose fin is the marker: in Finland a fish with the fin intact is wild, and in many waters wild fish must go back.
- Autumn river closures protect spawning fish. Coloured, dark fish in a river in October is the picture the rule exists for.
- Minimum sizes for sea trout are set separately from salmon and differ by country and by coastal area.
- Fishing in and around river mouths is often restricted even when the open coast is not.
In the kitchen
Handled as salmon, and the same fat-trimming logic applies: skin and belly flap off, cook so the fat leaves. A sea-run trout is leaner than a farmed salmon of the same size, so it dries out faster; the classic treatment is a light cure or a short hot-smoke rather than a long roast.
This is a reference page, not a fishing licence and not medical advice. Minimum sizes, closed seasons, bag limits and licence prices are set per country and per water body and change most years, so no number for them is printed here — each species page says which instrument sets the rule and where to look up the figure for the water you are standing on. If a clinician has given you a fish frequency or a contaminant instruction, that instruction outranks anything on this page.
Nutrition figures
| Per 100 g, raw | Amount |
|---|---|
| Energy | 104 kcal |
| Protein | 16.7 g |
| Fat | 3.6 g |
| Carbohydrate | 0 g |
| Fibre | 0 g |
| Salt | 0.1 g |
| Published row | Seatrout, raw |
Related published rows:
- Trout, mixed species, raw — 148 kcal per 100 g
Typical round weight for the calculator: 1.0–5.0 kg.
Eating advice: Finnish Food Authority and Swedish Food Agency national advice on Baltic and inland fish. Contaminant ceilings and the Baltic derogation: Regulation (EU) 2023/915; weekly tolerable intakes: EFSA methylmercury (2012) and dioxins/dioxin-like PCBs (2018). Nutrition figures: USDA FoodData Central rows published on this site. Checked 2026-09-06.
Frequently asked questions
How do I tell a sea trout from a salmon?
The differences the rule books rely on are the shape of the tail — a salmon's is more forked, a trout's squarer — the wrist of the tail, which is narrow on a salmon and thick on a trout, and the spot pattern, which extends below the lateral line on a trout. If you cannot tell, treat the fish as the more protected of the two and release it.
Fish in the same advice group
Baltic herring
Small herring freely; large herring over about 17 cm is limited for young people and in pregnancy.
Salmon (wild Baltic)
One to two times a month for young people and in pregnancy; farmed salmon is a different fish for this purpose.
European eel
The fattiest fish here and a critically endangered species — an occasional delicacy at most.
Baltic sprat
A short-lived oily fish; no size-based advisory of its own.
All species compared
The full table, grouped the way the advice groups it.
Eat the fish, log the fish
TempoLife tracks what you actually ate against the same food data linked on this page, so a fish meal shows up in your omega-3, vitamin D and salt totals without a second thought.