Marine Invaders

Help track non-native invasions taking place around the UK’s coastline...


Our seas in the UK are being invaded by an intriguing array of marine animals and seaweeds. Once established, they may be harmful to our native diversity by outcompeting them or by introducing disease. Others bring benefits, such as the tasty edible Pacific Oyster and can benefit our local species by creating habitats and shelter. We are asking you to join us as we survey the shores around the UK. It’s easy to get involved and all the family can take part.


These timed searches can be done on rocky shores, sandy or muddy beaches, or on man-made structures such as sea defences.


These surveys can be done at any time of year and only take 10 minutes. Just make sure you go at low water to be sure you can access the shore.


Print out the relevant recording sheet and protocol for the type of shore you want to visit (rocky shore, sandy/muddy or man-made structure), choose a species to look for, then try to find it!

Once you have conducted your search, the most important thing is to remember to upload your data at Don't forget, if you don’t find any Marine Invaders, this is just as important for us know!


This is a very simple survey that only takes 10 minutes of your time. You can complete a search alongside a walk at the coast or even on your lunchbreak! We need as many eyes as possible looking for Marine Invaders, to help us track their spread.

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Marine Invaders

Help track non-native invasions taking place around the UK’s coastline...


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Other citizen science projects

Why not take the skills you have gained from CoCoast to other citizen science projects? Many of the CoCoast partners run other citizen science or volunteering projects you might be interested in – click on the links below for more information!

Beachwatch (MCS)
Big Seaweed Search (MCS)
Wildlife Sightings Programme (MCS)
SeaSearch (MCS)
Sea Champions (MCS)
Shore Things (MBA)
BioBlitz (MBA)
Sea Survey (MBA)
FreshWater Watch (EarthWatch)