Support Our Claws!

Your support will make a huge difference.

We’re on a mission to help save one of the UK’s most endangered native species – the white-clawed crayfish.

With your support we plan to open a Conservation Breeding Centre at Marwell Zoo, helping to increase crayfish numbers and providing a safe haven before they can be released into ark sites or back into wild populations within Hampshire.

The white-clawed crayfish is the UK’s only native freshwater crayfish, but their survival is under threat. Thought to have drastically declined within Hampshire since the 1970s, we must take action to save this species or risk them being lost from our precious chalk streams forever. These unimposing little crustaceans are critical to maintaining chalk stream ecosystems and without them, the delicate natural balance could be completely thrown out.

Thanks to donations received during the Big Give Green Match Fund week and our Champion funder, Postcode Green Trust, we’ve already raised £20,380!  It’s not too late to show your support and donate.

Let’s give this important species a home at Marwell Zoo and ensure their survival for generations to come. Thank you.

A critical species

The UK has 85% of the world’s chalk streams.  They are ecologically rich thanks to the pure, clear water that flows from underground making them the perfect home for freshwater species such as trout, kingfishers, water voles, damsel flies and white-clawed crayfish.

We’re fortunate to have two of the most iconic chalk streams in the world right on our doorstep in Hampshire – the River Test and River Itchen. Swans, otters, newts and heron build their homes on these important waterways, creating a food web that supports itself.

Key to the success of the rich ecology is an important clean-up crew in the form of native white clawed crayfish. These unimposing little crustaceans are critical to maintaining chalk stream ecosystems and without them, the delicate natural balance could be completely unbalanced. 

As well as eating dead plant matter from the bottom of streams, they dig burrows that provide refuge for all manner of living things and are an important food source for other wildlife.

But white-clawed crayfish are Endangered! Habitat loss, pollution and the introduction of invasive non-native signal crayfish, have pushed white-clawed crayfish to the brink. Signal crayfish carry a crayfish plague, a disease that doesn’t affect them, but kills their white-clawed cousins.

White-clawed crayfish need our help!

Across Hampshire, ark sites are already being identified and established. The arks are isolated bodies of water that are selected to support healthy, self-sustaining populations of white-clawed crayfish, and safely away from the non-native species and crayfish plague. In the future, we hope to establish an ark here at Marwell too, but right now the urgent need is for a local breeding and rearing facility.

Our new Conservation Breeding Centre will not only be an important facility for breeding and rearing crayfish for release, but it will also be an important awareness and engagement hub locally. Guests to Marwell Zoo will have the opportunity to view crayfish, observe our work and learn about the importance of our local Hampshire chalk streams and how we can all take action to protect them.