Sometimes it seems like no matter how hard salmon farmers fight, sea lice always win in the end. With the parasites increasingly developing resistance to treatments like hydrogen peroxide the temptation might be to boost dosages. However, as new research from Kathy Overton (Institute of Marine Research, Norway) shows, more is not necessarily better.

Hydrogen peroxide is arguably one of the longest-running and most widely used delousing treatments employed by salmon aquaculture. Unlike other treatments such as emamectin benzoate and flubenzurons, when hydrogen peroxide hits the sea it breaks down into its natural components – hydrogen and oxygen – making it one of the most environmentally friendly solutions available. It is also one of the riskiest treatments in terms of salmon survival, but also among the most effective for delousing.

Given the risks, it may seem strange that farmers would consider upping the amount of hydrogen peroxide they expose their fish to, but the impacts of sea lice can be devastating...

This article was written for (and can be read in full at) The Fish Site.