Zoo Celebrates Releasing Thousands of ‘Giant Spiders’ that Grow to Be the Size of a Human Hand

The Chester Zoo in England reports that the fen raft spiders “just had the biggest mating season on record” after they almost became extinct

The Chester Zoo is looking back on a monumental achievement.

The English zoo celebrated 10 years since they released thousands of giant fen raft spiders into the United Kingdom after the species almost became extinct, the Chester Zoo wrote on Facebook.

“Ten years ago, we helped release THOUSANDS of GIANT spiders back into the U.K.,” the zoo captioned its celebratory post. “The fen raft spiders were bred right here at the zoo, and we’re super happy to report there are now more than 10,000 breeding females… and they’ve just had the biggest mating season on record!”

The zoo continued the post by emphasizing the arachnid’s large size, stating that spiders can “grow to be the size of your hand!”

“Honestly, you’re so welcome,” the Chester Zoo playfully concluded.

In an August news release, Chester Zoo detailed its efforts to save the fen raft spider from extinction after “people destroyed its wetland home.” First, the zoo’s team of experts gathered “hundreds of baby spiders” in individual test tubes to ensure their safety as part of a rescue program with the Royal Society for the Protection of Birds.

From there, the zoo cared for the young spiders until they were “strong enough to be returned to their natural habitat.”

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RSPB site manager Tim Strudwick recently told BBC about the importance of the species. “These spiders have an important role in maintaining the rich aquatic diversity found in the grazing ditches on our reserves,” he said.

The animal advocate also noted that the female spiders “are truly special to see.”

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According to Discover Wildlife, fen raft spiders tend to eat other spiders, damselflies, dragonfly larvae, and tadpoles. The spiders are brown and have white or cream stripes along their bodies. Despite their intimidating size, they are harmless to humans.

The London Zoo states that the spiders have only been found in East Anglia, Sussex, and South Wales in England, with additional small populations in Central Europe.

The International Union for Conservation of Nature currently considers the species “vulnerable” due to a decline in the spider’s habitat and adult population.