This is Harry the hermit crab, who lives in a rockpool at the Atlantis Discovery Area at Legoland in Windsor.
He's obviously as a big a fan of Lego bricks as the 1.9 million or so people who visit the Berkshire theme park every year, as given the choice between more traditional shells and one made from blue, red and yellow bricks, he chose the latter.
Legoland's senior aquarist Liane Riley said: "We decided to give Harry a wider choice and the model makers here created a special Lego house just for him.
"We weren't really sure if he'd actually move in, but he rejected the sea and snail shells on offer and seems very comfortable in his new home."
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