Sea lice abundances continue decreasing in Chile

Christian Pérez Between the seventeenth and twenty-third week of this year, 55 farming sites have been reported as with an average abundance of adult lice (Caligus rogercresseyi) per fish equal or higher than 9 parasites per fish according to the National Service of Fisheries and Aquaculture (Sernapesca). These sites with high abundances, known as Sites of Large Spread or CAD, are located exclusively in the regions of Aysén (36 sites) and Los Lagos (19). From the 55 total CAD in Chile, 13 sites were farming Rainbow trout, while the rest was stocked with Atlantic salmon. Meanwhile, just 4 CAD were being harvested, while the other 53 sites were in the process of fattening fish. In terms of companies, Mainstream is the salmon producing company with most CAD in the period with 11 sites and followed by Multiexport with 9 CAD. According to the new sanitary programme of control and surveillance of Caligus, if a farming site is not able to reduce the abundance of sea lice below 9 adult lice per fish within 6 weeks after notification, there will be a mandatory elimination of 25% of the biomass in that site.