Tracking the Environmental Impact of Sea Cages

When the aquaculture industry sinks new sea cages into the ocean, ecological issues float to the surface.

These mesh enclosures cause acute and long-term impacts on surrounding ecosystems, a result of both legal and illegal activities.¹

Take just one example. In 2013, Cooke Aquaculture pleaded guilty to the illegal use in their salmon farms of the insecticide cypermethrin, which killed several hundred pounds of lobsters and other crustaceans in the surrounding area.²

Even routine sea cage operations significantly impact nearby waters.

The ongoing discharge of untreated waste, including fecal matter, uneaten feed and harmful chemicals, such as antibiotics and pesticides, creates pollution hot spots.³ These nutrient overloads can lead to the formation of dead zones – areas with such low oxygen levels that marine life cannot survive.⁴

Toxic waste from these facilities leaches into the marine environment, disrupting delicate ecosystems and compromising the health of coastal habitats. In one study, scientists estimated that exposure to aquaculture discharge at newly proposed sites in Newfoundland could extend more than five miles (eight kilometers) in every direction.⁵

Additionally, plastic debris and discarded equipment from the sea cages accumulate in nearby waters and wash up on shores, contributing to long-lasting environmental damage.^{6, 7}

The havoc that sea cages wreak is just one reason, among many, that more countries are instituting sea cage bans that will protect their oceans, their coastlines and the communities along them.