Fish-eating giant spiders the size of rats are making a comeback in the UK, experts have said.
Thousands of fen raft spiders (Dolomedes plantarius) have been reported across the UK, in East Sussex, Suffolk, and Swansea. Between 2010 and 2015, four new populations were established in the Norfolk Broads through a translocation programme.
The spiders were almost extinct in 2010, but conservationists have carried out extensive work to bring back the species.
The RSPB say the scary arachnids are set to have their best year on record at a number of nature reserves.
The conservation charity revealed that the most recent survey estimates the total number of female spiders to be up to 3,750 across 12 sites in Norfolk and the Suffolk Broads alone.
Tim Strudwick, the RSPB Mid Yare nature reserves site manager, said: ““The fen raft spider is one of the UK’s rarest invertebrates and we are proud of the role our reserves and teams have played in its recovery.
“These spiders have an important role in maintaining the rich aquatic diversity found in the grazing ditches on our reserves. The females are impressive in size, but also beautiful – they are truly special to see.”
RSPB ecologist Jane Sears, who is also involved in fen raft spider conservation, added: “The RSPB has played an important role in the reintroduction of these spiders and means we must continue to restore, manage and protect the wetland habitats where the fen raft spider thrives to ensure the future of not just this species, but many others, too.”
Here is what we know about the not-so-mini beasts.
What are fen raft spiders?
The fen raft spider has a brown or black body with white or cream stripes along the sides. With a span of up to almost three inches (8cm), they are the largest of the UK’s 660 native species of spider.
The spider can spin a web as large as 25cm and can grow bigger than a man’s hand.
Where are fen raft spiders found in the UK?
The species only lives in fens, marshes and wetlands, using their long hairy legs to run across the surface of water.
They were previously close to extinction and Chester Zoo took on a breeding conservation project in 2011 to boost their numbers. Now they are thriving in a number of RSPB sites.
Are fen raft spiders poisonous?
Those scared of spiders will be pleased to know they are not venomous but do look terrifying due to their size. They also are semi-aquatic, which means they can run across water to capture their prey. Their diet includes other spiders, damselflies, dragonfly larvae, and even fish and tadpoles.
