Sea Lice Biology, Identification and Laboratory Methods

Introduction: This section provides a brief overview of aspects of sea lice biology and simplified methods to identify the difference species found on salmonids in British Columbia. The term sea louse (pl. sea lice) is the common name used for several species of marine ectoparasitic copepods of the family Caligidae (Order Copepoda: Suborder Siphonostomatoida) that infect fish. In B.C. these species include Caligus clemensi, Lepeophtheirus salmonis, and Lepeophtheirus cuneifer that have been reported from salmonids and nonsalmonid hosts. In addition to these species there are another nine species of Lepeophtheirus and one species of Caligus reported from numerous non-salmonid hosts (Margolis and Arthur 1979, Kabata 1988; Johnson and Albright 1991a; McDonald and Margolis 1995). Emphasis here is only on C. clemensi, L. salmonis, and L. cuneifer that use wild and farmed salmonids in British Columbia waters as hosts. For more detailed reviews of their sea lice biology readers should consult Pike and Wadsworth (1999), Tully and Nolan (2002), Johnson and Fast (2004) and Johnson et al. (2004). An identification key for the adults of species of sea lice found in British Columbia is given in Kabata (1988).Peer reviewed: YesNRC publication: Ye