Fen Raft Spiders Flourish in Wild After Zoo Release

Conservationists have reported that thousands of “giant spiders,” released into the wild by a zoo, are now thriving and have experienced a record mating season. Chester Zoo released these spiders a decade ago as part of a joint project with the RSPB, which aimed to save the species from extinction. This year, more than 10,000 breeding female Fen Raft spiders have been recorded. Zoo bosses have hailed the breeding programme “a success,” noting that the arachnids could “grow to be the size of your hand” and therefore “you can’t miss them.” The Fen Raft spider played a crucial role in maintaining healthy aquatic ecosystems but faced near extinction 15 years ago after its wetland habitat was destroyed by human activity, as stated by the zoo. To prevent cannibalism, baby spiders were bred in individual test tubes, with zoo staff using tweezers to hand-feed them tiny flies. A zoo representative explained, “Eventually, the young spiders grew strong enough to be returned to their natural habitat, which [the RSPB] worked to restore, and we released them in their hundreds.” On X, Chester Zoo posted: “We’re super proud to be part of this conservation breeding rescue programme, working alongside our friends at the RSPB to prevent the extinction of the Fen Raft spider.” The zoo also noted that the spider is identifiable by “an eye-catching white stripe that runs along their body.” Tim Strudwick, nature reserves site manager for RSPB Mid Yare in Norfolk, commented: “These spiders have an important role in maintaining the rich aquatic diversity found in the grazing ditches on our reserves.” He further described the females as “impressive in size, but also beautiful – they are truly special to see.”