Fen raft spider
Charity: Suffolk Wildlife TrustCharity:
Fen raft spiders for the FutureWhere in the World?
Three grants totalling £42,960.
The Fen Raft Spider lives in only three places in the UK, making it one our rarest animals.
In the Redgrave and Lopham Fen National Nature Reserve, one of those last outposts, it lives in just two secluded spots. This is despite measures to restore much of the surrounding habitat to its best possible state. This colourful and scarce invertebrate has very limited powers of movement. It is apparently unable to spread further afield or to other areas of the same fen, even if the conditions are absolutely right. This makes it highly vulnerable to extinction.
Another threat to fen raft spider survival is the loss of genetic variability identified in the East Anglian population. This potentially decreases the ability of the remaining spiders to adapt to any future changes in the wetland habitat as a result of climate change or other pressures.
How your money has helped
With an initial grant the Suffolk Wildlife Trust carried out a feasibility study into translocation (or movement) of spiders within the reserve from existing sites to new areas. The study included genetic analysis and an ambitious captive breeding trial to boost the population.
The wider community was engaged to support the project through Suffolk Wildlife Trust events. The new sites receiving relocated spiders were prepared to provide the best possible habitat conditions by local volunteers recruited via the publicity drive.
Important experience and vital knowledge for successful future reintroductions was gained as a result of the feasibility study.
Further work to reduce fen raft spider vulnerability on the fen and at a wider scale was then supported. Additional relocation work further afield will establish a population on a new site prepared at Castle Marshes on the river Waveney in Suffolk. †Finally, with enthusiastic support from British zoos a captive breeding programme was established.† Spiderlings from this programme have been successfully translocated to a Suffolk Wildlife Trust and work is underway to establish further suitable sites for re-introduction within the Broadland Living Landscape.
The public have had an opportunity to engage with the beauty and fragility of this rare fen jewel through an artist residency at Castle Marshes and through opportunities to see the spiders in their new location. The Suffolk community have been observing the precarious status of the fen raft spider - a local story of a small species, but with a larger resonance in the world today.