Juan E. Trigo, Meritxell Mondéjar
The observations carried out during the spring of 2014 on different Atlantic salmon (Salmo salar Linnaeus, 1758) sea farms around the island of Frøya (Sor–Trøndelag), Norway, served to lay the foundations for a totally natural and environmentally friendly method for removal salmon parasitic copepods known as sea lice.
The method is based on two known data: the different stages of copepod larval development, some of which are free-living as part of plankton and the existence of marine invertebrates that feed on plankton and more specifically on zooplankton, that is, the animal part of the plankton that is where the copepod larvae are.
If we combine these two facts, we obtain the main idea of the method: introducing marine invertebrate filter feeders in special devices (patent pending) inside the cages of the marine farms, it will only be necessary to let these invertebrates carry out their natural function of feeding based on copepod larvae, that is, when they are in their most vulnerable phase and in which they have not yet caused harm to the salmon. In this way, sea lice can be eliminated without the use of chemicals, medicines or methods that can cause unnecessary stress to salmon on sea farms.