Species

European flounder

A flatfish of coasts and estuaries that loves brackish water, travels far up rivers and is a classic for surf casting.

Platichthys flesus

Photo: Hans Hillewaert, Wikimedia Commons, CC BY-SA 4.0, adjusted to 3:2

Spawning: In the southern North Sea February to May, in the far north April to June, at sea (general guide, varies by region)
German Red List: not threatened
Typical method: Surf casting
Top bait: Lugworm

Plan a day fishing for European flounder

How to recognise it

Oval, strongly flattened body, eyes usually on the right side
Rough bony knobs along the lateral line and the base of the fins
Small mouth, often pale reddish spots on the upper side

Easily confused with: Looks like the European plaice: the flounder feels rough along the lateral line and the edge of the fins, the plaice is smooth and has bright orange spots.

How to catch it

Methods: Surf casting, Bottom fishing from a pier or boat, Drift fishing with a flatfish spoon (Buttlöffel)

Baits: Lugworm, Ragworm, Mussel meat, Flatfish spoon with worm

In the evening and at night, when it goes looking for food; during the day it often lies buried in the sand.

Habitat and food

Sandy and muddy coasts from the North Sea and Baltic Sea to the Mediterranean, preferring brackish water in estuaries, inlets (Förden) and bays; individual fish migrate far up the rivers.

Isopods, amphipods, molluscs and bristle worms; in fresh water mainly midge and caddisfly larvae.

Size and age

Usually 25 to 30 cm and around 300 g, maximum 50 cm (Wikipedia). FishBase, on the other hand, gives a maximum of 60 cm, a heaviest published weight of 2.9 kg and a maximum age of 15 years.

Protection and rules

Conservation status: German Red List (marine fish 2025): not threatened. IUCN: not threatened (Least Concern, 2022). The Baltic flounder (Platichthys solemdali) has been regarded as a separate species since 2018 (Red List: data deficient).

European flounder: closed season and minimum size by German state

These rules apply in Germany only. Fishing in the UK, the USA or elsewhere? The local rules apply there (link below).

Berlinno minimum size, no closed season
Bremenminimum size 25 cm
Hesseprotected all year
Mecklenburg-Western Pomeraniaminimum size 25 cm (coast)
Rhineland-Palatinateprotected all year
Schleswig-Holsteinminimum size 25 cm · closed season 01.02. to 30.04. (coast) only in some waters

From the official state fisheries regulations, retrieved 2026-10-11. All rules by state

Check the rules

In Germany, closed seasons and minimum sizes are set by each state and can be stricter for single waters. All German rules by state, with the legal source. Outside Germany, the local rules apply: licence and agency by country.

In the kitchen

A popular food fish, in the north often called Butt in German; classically pan-fried or smoked.

Sources (4)

Last checked 2026-10-18. Found a mistake? Write to [email protected].

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