Norwegian salmon giant SalMar was forced to cull approximately 1.2 million salmon in November following a jellyfish attack at one of its sites.

The world's second largest salmon farmer said Thursday in mid-November farmers at its Ornfjordbotn location in Senja, Norway, observed a "significant and threatening influx" of Apolemia uvaria jellyfish, also known as string jellyfish or barbed wire jellyfish.

A few days later, the amount of jellyfish increased further and the extent of damage to the salmon worsened.