The Coast Guard announced Tuesday that it will install mariner radio-activated sound signals on seven remote lighthouses along the coast of Maine.

The devices allow mariners to activate lighthouse sound signals on demand – the signal shuts off after 60 minutes – using a marine radio and will replace antiquated foghorns, which can emit sound continuously in foggy conditions.

Lt. David Bourbeau, a Coast Guard spokesman, said the new device reduces the negative effects that a continuous sound signal has on wildlife and migratory bird populations as well as the people who live near the lighthouses.

Bourbeau said radio-activated sound signals will be installed in May at Halfway Rock, Matinicus Rock, Mount Desert Rock, Great Duck Island, Petit Manan Island, Libby Island and the Little River Lighthouse. The Coast Guard replaced fog detectors at 17 Maine lighthouses last year.