Babies of huge spiders to be introduced on Broads

ONE of Britain’s rarest and most spectacular spiders is to be introduced to the Norfolk Broads on Wednesday after an intensive captive breeding programme.

A thousand hand-reared fen raft baby spiders or spiderlings will be released on the RSPB’s Mid-Yare reserve in an effort to generate new populations of this vulnerable species in Norfolk, where they are now restricted to a single site.

The fen raft spider, (Dolomedes plantarius) is Britain’s biggest spider and can grow to the size of a woman’s palm with a body length of 23mm. It can literally walk on water to catch its prey but owing to deterioration and loss of wetland habitats, its population has suffered. It is listed as Vulnerable on the IUCN’s Red List of Threatened Species and as Threatened in the UK Red Data Book.

The fen raft spider is only found on three wetland sites in the UK - Redgrave and Lopham Fen National Nature Reserve in Norfolk where it was first discovered in Britain in1956, the Pevensey Levels in Southern England and in South Wales.

The release of the baby spiders will be watched by their foster parents, mainly staff from zoos, who have patiently reared them in individual test-tubes over the summer. The spiderlings have been bred from the wild population at Redgrave and Lopham Fen Reserve.

Pictured is a male fen raft spider at Redgrave and Lopham Fen, taken by Helen Smith.