Common bladder wrack

Bladderwrack, Rockweed; scientific name: Fucus vesiculosus
Bladder wrack
Forked thallus of the bladder wrack
Photo: UPB-Projektgruppe Trier

Common brown alga of the coastal areas of the North and Baltic Sea

Common bladder wrack (rockweed, or brown alga) is one of the macrophytic alga which have long been used in monitoring programmes as indicators of accumulation. As one of the most widespread algae in the northern hemisphere, it lends itself particularly well to the comparative analysis of coastal water pollution.

The forked thallus is used as a specimen. Sampling takes place every two months.

For more information about the specimen, the sampling and the processing of samples see the Richtlinie zur Probenahme und Probenbearbeitung Blasentang (Fucus vesiculosus) (German)

Sampling area


Sampling period

1985 - 2022

Extended information

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