underwater

"When other fish get caught in those nets they sort of flail and it sends out a vibration underwater, sort of like ringing the dinner bell," says Prof Pepin-Neff.

But when wasting disease in effect wiped out their main predator, the sea urchins exploded in number, decimating kelp forests and transforming once-lush underwater habitats into so-called urchin barrens.

The farms are on rich peat soil that used to be underwater but is now slowly drying out.

A catastrophic flood could put many areas of the state underwater, threatening lives and property on an unprecedented scale, experts say.

The flooding washed away several key bridges, submerged vehicles and left the ground floors of homes underwater.