Silvery grayling live in the lakes of North Finland and the coastal areas of the Gulf of Bothnia, but migrate into streams during springtime. They have a tall brush-like dorsal fin that particularly males like to display proudly during territorial disputes. The grayling requires cool and oxygen-rich water. Its diet is similar to that of trout and consists of bottom-living mollusk, insect larvae and crustaceans. It is viewed as a serious competitor to trout. The grayling can grow up to half a meter in length and weigh one kilogram; like trout, it is a savoury and highly appreciated food fish.