Impact of Caligus research carried out in Chilean aquaculture by Universidad de Los Lagos

Research on Caligus rogercresseyi (Boxshall & Bravo, 2000) in Chile started in 1996 with funds provided by Fondecyt (grant 1961151) and IFS (Sweden). Main topics of this study were the role of salinity on sea lice development, identification of native fish which transmit the parasite to salmonids and the comparative susceptibility of native sea lice to the three species of salmonids cultured in Chile. In 1997 a FDICorfo grant funded research into the description of the life-cycle of this caligid in trout reared in sea water tanks and in the preparation of a manual for the management of the disease. In 1998 another Fondecyt grant (1980079) allowed the study the feasibility of using Udonella australis (Carvajal & Sepulveda, 2002) as a biological control for Caligus. During 2005, two research projects funded by Fondef were accepted: DO3I 1155, which evaluates the efficacy of an attractant bait for copepodids in order to decrease the caligus numbers in salmon farming sites and AQ04I 1025, which studies the role of semiochemicals in the alteration of the reproductive behaviour of Caligus in order to decrease the fecundity of the parasite. With the support of several salmon farming companies, we are studying the efficacy of fallowing of sites in marine fish culture in order to diminish the number of Caligus copepodids in high risk areas. Two projects have been launched for research funding in 2008, one investigation presented to Fondecyt deals with “Biological basis for the control and management of the epizootic caused by Caligus rogercresseyi in cultured salmon Salmo salar: importance of the spatial - temporal dynamic, larval dispersal and hosts reservoir”. The other proposal presented to internal funds of the Universidad de Los Lagos, is about “Temporal evolution of the horizontal distribution of one cohort of planktonic Caligus rogercresseyi larvae from culture sites of Atlantic salmon in Chile fjords”. At this very moment we are preparing the final report of the 1050547 Fondecyt grant, which includes the experimental capacity of Caligus rogercresseyi to infect the estuarine fish Galaxias maculatus (Jenys, 1842).