In the wild, Atlantic salmon will travel for thousands of miles. But, confined in barren, overcrowded cages on Scottish farms, they can do nothing more than swim in circles for up to two years.
Diseases and parasitic sea lice thrive in these intensive conditions. Not only do these lice inflict painful wounds and eat salmon alive; the treatments to remove them, such as chemical baths and hot water exposure, cause the salmon additional pain and stress. Many of the salmon we found were carrying countless sea lice.
The mortality rates for fish on Scottish farms are shocking. These unacceptable deaths can be caused by disease, parasites, injuries, and negative reactions to handling. In our investigation, we found dead fish floating in the pens.
Also confined in the cages are ‘cleaner fish’, which farmers use in an attempt to remove sea lice from salmon. These intelligent creatures suffer from many welfare issues. Their use can be ineffective, their precious lives wasted; all are discarded without prior stunning once the salmon have been reared.
Dead salmon are sometimes dumped in landfill sites, exposed to wildlife – which can present a biosecurity risk.
Meanwhile, the water pollution caused by fish waste and chemicals from Scottish salmon farms can cause harmful algal blooms, from which farmed fish cannot escape. In addition, many of the chemicals released into the environment from these farms are known to be toxic to fish, birds and mammals.