Mowi Chile said it has begun moving essential staff and services by boat to Chile's Aysen region, following tighter coronavirus lockdown measures introduced by authorities.

A group of 50 people who all tested negative for coronavirus set sail on Saturday from the port of Koshifas in Puerto Montt, destined for eight production sites in the Aysen region.

Workers will be rotated under a 21-days-on, 21-days-off shift pattern to try to prevent the spread of the virus.

The coronavirus lockdown in Chile's southern Aysen region, home to a more a than a dozen salmon producers and suppliers, has tightened further with no one allowed in or out by air or road. People and goods now can only be moved by sea.

Measures extend to salmon producers, processors and suppliers, as well as their subcontractors. Evacuations from the area can only be made in case of emergency or prior notice and in coordination with Aysen health authorities.

While authorities imposed so called "sanitary cordons" around Chiloe Island in the Los Lagos region and Aysen, Chilean salmon processing plants are running at just over 50 percent of capacity, as companies step up safety measures, including flexible shifts, to try to prevent transmission of the virus between workers.

“It is of utmost importance in these uncertain times that the people of our team and their families arrive at work with the peace of mind of being in good health," Mowi CEO Fernando Villarroel said.

"Twenty-one days on, 21 days off is a long shift, which implies a great personal and family sacrifice, so it is important to be able to offer that assurance."