Environmental groups are among those appalled at plans to expand into Guernica and the Urdaibai reserve – but others welcome it

A large and almost comically sinister fish named Guggenheim is on the loose in and around the ancient Basque town of Guernica, its jaws perilously close to snapping shut on a twitchy-looking tiddler called Urdaibai.

Images of the predator and its prey have been proliferating on posters, bus stops and walls in the area since last summer as fears grow over what the suggested outpost of the Guggenheim Museum in Bilbao could mean for Guernica and the adjacent Urdaibai biosphere reserve.