The tiny parasite threatening your salmon sushi
Marine parasites known as sea lice are threatening the world's salmon supply. Today we eat three times more of the high-protein fish than in the 1980s, but the proliferation of sea lice is hitting farms hard - including those in Norway, the world's number one producer of Atlantic salmon.
Sea lice have always existed in nature but extensive farming has led to a surge. The tiny crustaceans latch onto the fish and eat them alive.
The Norwegian government has launched a national programme calling on the industry to find a solution to a crisis that is jeopardising the multi-billion dollar business.
While the parasite is the farmed Atlantic salmon industry's most expensive problem, it's also an ecological one. The reservoirs of sea lice are starting to impact wild populations, begging the question of whether our growing appetite for salmon is something society can sustain.