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Led by Wildwood Trust, the Saving Devon’s Native Crayfish project is the latest project to step up white-clawed crayfish (WCC) conservation efforts in Devon.
Thanks to funding from Natural England Species Recovery Programme, the project is developing a new crayfish hatchery, building a bespoke crayfish ark site pond, rescuing WCC from Devon rivers, and telling the story of WCC conservation through a new public display at Wildwood Trust Devon.
Following a successful trial period in early 2023 (funded by Devon Community Foundation), Natural England funding is enabling Wildwood Trust Devon to expand the crayfish hatchery facilities to accommodate native crayfish from across Devon and Somerset.
White-clawed crayfish rescue surveys
The Saving Devons Native Crayfish (SDNC) project team re-started crayfish rescue surveys in the Rivers Creedy Yeo and Culm in April 2024. The aim of these early season surveys is twofold:
· To capture ‘berried’ white-clawed crayfish (females carrying fertilised eggs) to take to the Wildwood Devon hatchery. With mating complete in the wild, and the eggs already fertilised, the hatchery team can give the eggs and any surviving hatchlings the best chance of survival away from the threat of predation in the river. Click here for more information about the WCC lifecycle.
· The surviving white-clawed crayfish populations in both Devon rivers are under threat from non-native invasive American signal crayfish which are rapidly advancing into the WCC territory (and are already mixing in most places). The project team are therefore rescuing as many WCC as possible before it’s too late. Click here for more information on crayfish in Devon.
The survey team have been frustrated by bad weather over the first month of surveys with river levels too high for safe access.
They have also set out traps only for these to be dislodged by high flows after recent storms.
No berried females have been found so far, and due to the challenging weather, no surveys have taken place yet this year in the Creedy Yeo.
The team have had more success on the River Culm with a total of 12 white-clawed crayfish found and rescued from the River Culm already this year (only 3 were found in 2023).
This includes 4 females which means the team now have a viable Culm captive breeding population!
The team need a special Natural England survey licence to carry out these early season surveys as they are taking place outside of the normal, white-clawed crayfish survey season (Jul-Sep).
They need a separate Natural England licence to be able to take WCC from the river to the hatchery, and Environment Agency trapping permits to be able to use any kind of crayfish traps.
Landowner permission is also required.
Crayfish taken to the hatchery are transported in insulated cool boxes containing ‘floss’ material which protects them on their journey.
Captive Breeding Success!
In January 2024 the hatchery team found that Creedy Yeo females bought into the hatchery in 2023 were berried (carrying fertilized eggs) and means the crayfish successfully mated in the hatchery - a major milestone for the project.
WCC are difficult to breed in captivity and so for the Wildwood Devon team to achieve this in the first year of hatchery development is exceptional, and a testament to the hours of hard work and dedication of the hatchery team!
Running the hatchery is a key part of the project and requires daily attention, 7 days a week. This includes feeding crayfish, monitoring water temperature and quality, checking equipment is working and changing the water in tanks on a weekly basis. Click here for more information about the hatchery.
The Devon survey team use two different trapping survey methods:
Wildwood Devon public crayfish display
From summer 2024 Wildwood Devon visitors will be able to find out more about white-clawed crayfish conservation through a new visitor display.
The display will tell the story of crayfish in Devon and explain the latest conservation methods being used to safeguard the species from extinction.
Visitors will be able to see captive raised WCC in an aquarium display and learn about crayfish lifecycles.