TempoLife › Features › Fish: minimum sizes, closed seasons and eating advice › crayfish
Noble crayfish
Noble crayfish (Astacus astacus), Lean and low-risk to eat; the real risk is what you carry between waters.. The national eating advice, why it applies, the rules that matter when you catch it, and what the kitchen changes about the numbers.
Crayfish plague: never move live crayfish, wet nets, boots or boats between waters.
Where it lives
Clean, hard, well-oxygenated streams and lakes with stony bottoms and undercut banks. The native noble crayfish was once the basis of an export industry across this region and is now patchy, protected and locally extinct in many waters. The late-summer crayfish season is a fixed social event in Finland, Sweden and Estonia alike, and it is short by design.
Why the advice says what it says
As food, crayfish is the least complicated thing on this page: lean, high in protein, very low in fat, low in the food chain and eaten in small quantities. The risk it carries is not to the eater but to the water. Crayfish plague, caused by the water mould Aphanomyces astaci, is carried without symptoms by North American crayfish and is lethal to the native noble crayfish; it is the reason native populations collapsed across Europe. The signal crayfish that carries it is listed as an invasive alien species of Union concern under EU law, which means it may not be kept alive, bred, transported or released. The spores travel in water, and therefore in a wet net, a wet boot, a bucket, a boat bilge. This is why the single most important rule on this page is not about size or season: never move live crayfish between waters, and dry or disinfect gear completely before using it somewhere else. The one organ worth a note at the table is the hepatopancreas — the soft, rich, orange "butter" in the body cavity. It is a digestive organ and the fattiest part of the animal, which is where anything fat-soluble would sit.
The advice
| Who it applies to | What the advice says | Where it comes from |
|---|---|---|
| Everyone | No frequency restriction. Lean, low-trophic and eaten in small quantities. | Absence from national advisories; reasoning from the diet and fat content |
| Anyone eating the soft body contents | The hepatopancreas is a digestive organ, not muscle. It is a delicacy, and a delicacy portion is the right portion. | Reasoning from its function and fat content |
| Everyone handling crayfish or gear | Never move live crayfish or wet equipment between waters. This is a disease-control rule, not a courtesy. | EU rules on invasive alien species of Union concern; national crayfish plague controls |
The rules
What the rule book says about this fish, described by instrument rather than printed as a number:
- The crayfish season is short and fixed in the national fishing rules, and it does not open at the same moment everywhere.
- Crayfish traps require a named permit almost everywhere in the region, and permits are often numerically limited per water.
- A minimum size applies, and undersized animals go back immediately.
- Signal crayfish is an invasive alien species of Union concern: it may not be kept alive, transported or released, and the handling rules for it differ from those for the native species.
- Some waters are closed to crayfish fishing entirely to protect remaining noble crayfish populations.
In the kitchen
Boiled in heavily salted water with crown dill, cooled in the liquor, eaten cold with bread and something to drink. The edible tail meat is a small fraction of the live weight — far smaller than a fish fillet — so a crayfish party is measured in animals per person rather than in grams. The claws of a noble crayfish are worth opening; the body contents are the part people argue about.
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 | 72 kcal |
| Protein | 14.9 g |
| Fat | 1 g |
| Carbohydrate | 0 g |
| Fibre | 0 g |
| Salt | 0.2 g |
| Published row | Crayfish, raw |
Related published rows:
- Crayfish, cooked — 87 kcal per 100 g
- Wild crayfish, raw — 77 kcal per 100 g
Typical round weight for the calculator: 40–110 g.
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
Why can I not move crayfish from one lake to another?
Because crayfish plague spreads in water and on wet equipment, and North American crayfish carry it without dying of it. Moving a bucket of live crayfish, or an undried net, can end a native population that has survived for centuries. In the EU the invasive species involved is also legally restricted from being kept alive or transported.
Fish in the same advice group
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.