Big Seaweed Search

Family looking for seaweeds in a rockpool

At a glance

Identify and record seaweeds.

Type of activity: Outdoors

Who can take part? Everyone

When? All year round

Where? UK seashore

How long will it take? About one hour

Cost: Free

Explore the UK coastline and record the living seaweeds you find to help us monitor the effects of climate change and invasive species.

Why we are doing the project

Seaweeds are at the base of the marine food chain. Like plants on land they photosynthesise, taking in carbon dioxide and turning the Sun's energy into food. Many animals rely on seaweeds for food and shelter.

Changing sea conditions, climate change and the arrival of invasive species such as wireweed may be having an impact on the ecology of UK seaweeds and many other marine organisms.

To assess this impact, we need to track the changing distribution of seaweeds around the UK. We would like your help to record 12 species of red, brown and green seaweeds.

How to take part

1. Read the instructions and identification guide PDF (1.9MB) to find out which species we are targeting.

2. Go for a walk along the seashore and look for living examples of any of the 12 seaweed species.

3. Note your sightings on a recording form PDF (360KB).

4. Email a copy of your completed form to or post it to:

Big Seaweed Search
Angela Marmont Centre for UK Biodiversity
The Natural History Museum
Cromwell Road
London SW7 5BD

You can send in records at any time of the year and as many times as you like.

Project team

In partnership with:

Funded by:

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