If you happen to be visiting Wellington airport over the next few months, don't be surprised to be greeted by Gollum, the miserable creature at the centre of JRR Tolkien's The Lord of the Rings and The Hobbit.

A 13m (43ft) sculpture, built by Japanese artist Masayuki Ohashi out of polystyrene and epoxy resin using chainsaws and robotics, has been installed at the airport to celebrate the arrival in cinemas next month of Peter Jackson's first Hobbit film, An Unexpected Journey. The movie forms part of a new prequel trilogy to the Kiwi film-maker's Oscar-winning Lord of the Rings triptych, in which Gollum is once again played by British actor Andy Serkis via motion capture technology. The airport has also renamed its terminal, where passengers will be greeted with a sign saying they have arrived at "the middle of Middle-earth".

The giant Gollum was unveiled on Friday, according to Fairfax NZ News. It features three 4m fish suspended in front of the creature – along with with bubbles – as he dunks his hand in to try to catch one. In The Hobbit, Tolkien's 1937 children's tale, hairy homunculus Bilbo Baggins first encounters Gollum in the dark caves of the Misty Mountains, where he lives a (relatively) contented existence fishing for blind, bug-eyed prey in murky pools and occasionally murdering passing goblins. The character returned to play a vital role in the The Lord of the Rings, Tolkien's much longer, far darker 1954-5 sequel trilogy.

The sculpture was designed by Weta Workshop, the Wellington-based special-effects outfit that won three Oscars for its work on The Lord of the Rings and has returned for The Hobbit. "Wellington airport feels like the home of Gollum after spending so many months here during the last three films," said Richard Taylor, Weta co-founder and creative director. Sculptor Ohashi added: "It was a very exciting project to work on."

The first Hobbit film, starring British actor Martin Freeman as Bilbo, will be released on 14 December in the UK and US, with the second (subtitled The Desolation of Smaug) debuting in December 2013. The final instalment, There and Back Again, is due to arrive in summer 2014 after being announced as a belated addition in July.