Many sea louse species are specific with regard to host genera, for example "L. salmonis", which has high specificity for anadromous fish including sticklebacks and salmonids including the widely farmed Atlantic salmon ("Salmo salar"). "Lepeophtheirus salmonis" can parasitize other salmonids to varying degrees, including brown trout (sea trout: "Salmo trutta"), Arctic char ("Salvelinus alpinus"), and all species of Pacific salmon. In the case of Pacific salmon, coho, chum, and pink salmon ("Oncorhynchus kisutch", "O. keta", and "O. gorbuscha", respectively) mount strong tissue responses to attaching "L. salmonis", which lead to rejection within the first week of infection. Pacific "L. salmonis" can also develop, but not complete, its full lifecycle on the three-spined stickleback ("Gasterosteus aculeatus"). This has not been observed with Atlantic "L. salmonis".