By Ben Harder
Marine parasites known as sea lice spread readily from farmed salmon to wild fish, according to a study of wild salmon in British Columbia. The researchers, funded by several environmental groups, say their work underscores a possible ecological hazard in aquaculture, but critics of the study question the value of its data.
Various sea lice occasionally latch on to the skin of wild saltwater fishes, reducing swimming efficiency and increasing vulnerability to diseases. These lice are a greater problem among farmed fish concentrated in pens.