
Cornish Sucker
This week’s Species in Focus is the Cornish Sucker. This unique looking fish may be little but packs a powerful ability to latch on to rocky surfaces using its adapted pelvic fins.
Love exploring rock pools? Curious about the weird and wonderful creatures living along our coasts?
Love exploring rock pools? Join the Big Rock Pool Challenge: National BioBlitz this May — a week-long mission to discover and protect marine life, help track invasive species and earn your Rock Pool Discovery Score. No experience needed — just curiosity and a love of the coast. Every record counts!
You don’t need any expertise – we’ll guide you step-by-step after sign-up.
Join the Big Rock Pool Challenge: National BioBlitz and help us create one of the most comprehensive snapshots of UK rocky shore biodiversity! It’s a fun way to make a real impact on our understanding of marine life.
1. Visit your local rock pool
2. Record what you find
3. Earn your Rock Pool Discovery Score
Remember to share your amazing discoveries on social media! Use #BigRockPoolChallenge and tag us – we can’t wait to see all your awesome finds.
17th to 25th May 2025
The Big Rock Pool Challenge: National BioBlitz is happening all across the UK — and anyone can take part, wherever they are. All you need to do is head to your local rocky shore, explore the rock pools, and record what you find using the iNaturalist app. It’s a flexible, week-long event, so you can choose the day that works best for you — whether that’s a sunny afternoon, a perfect low tide, or a moment of calm in a busy week. Take part on your own or with friends and family — and help build a national picture of marine life on our coasts.
A chance to ask questions and gain insights directly from marine science experts! Explore how your coastal observations can help shape UK policy and understand why monitoring our marine life matters—plus, get top tips for getting started with rock pooling.
Sign up hereSince the 1960s, over 20 invasive marine species have established on UK shores — and more are expected. These non-native species often arrive via shipping or climate shifts and can harm native wildlife and ecosystems. Many are small, under-recorded, and spreading.
The National BioBlitz, following UK Invasive Species Week, is your chance to help. By recording what you find, you'll support conservation and marine management across the UK.
Want to learn more?
Explore this fantastic Marine Non-Native Species ID Guide from our partners at the Marine Biological Association (MBA):
MBA Marine Non-Native Species Guide (PDF)
The Big Rock Pool Challenge is proudly funded by The ScottishPower Foundation and The National Lottery Heritage Fund whose generous support enables us to inspire communities and deliver lasting environmental impact across and beyond the South West.
This initiative is delivered in partnership with The Rock Pool Project and the Marine Biological Association. Together, we’re empowering people and their communities to connect with nature, contribute to valuable biodiversity data, and support the health of our coastal ecosystems for future generations.
This week’s Species in Focus is the Cornish Sucker. This unique looking fish may be little but packs a powerful ability to latch on to rocky surfaces using its adapted pelvic fins.
The Rock Pool Project Team pick out their top Rock Pooling Books
The broad-clawed porcelain crab is a charismatic little rock poolers favourite. It is the most common species of porcelain crab found in the UK and can often be found clinging tightly to the underside of rocks below mid tide level.