The boulders are to be sunk in zones classified as Natura 2000 in the Lilla Middelgrund (179 square kilometres, 70 square miles) and Flauden (104 square kilometres, 40 square miles) areas.

Both sites lie about 20 kilometres (15 miles) from Varberg port, off Sweden's southwest coast.

Natura 2000 is a network of sites around the European Union protected by EU directives aimed at protecting wildlife and their habitats.

Carrying out Monday's mission will be two Greenpeace vessels -- the Beluga II and the Fehn Coast -- with about 30 people on board.

"This is a conservation measure in order to protect habitats, which is what governments are supposed to do," Danielsson said.

A similiar initiative was taken last year off Germany, and according to Greenepace it has proven effective in discouraging fishing.

Bravo!