Two wooden sculptures and a bench have been stolen from Little Woolden Moss, close to Cadishead Moss, and Lancashire Wildlife Trust is asking people to look out for the objects around the area and on the internet.
It is the third time that Little Woolden Moss nature reserve has been targeted, with vandals wrecking a sculpture and another bench being taken.
The artworks were installed about a year ago on the Lancashire Wildlife Trust reserve as part of the Bog Hop Trail to introduce young people to different plants and animals on the moss.