Skull Morphology Variation as Related to Trophic Specialization in Three Forms of Salvelinus malma (Salmonidae) from the Kamchatka River Basin.

New data on the correlation between morphology and trophic specialization of three riverine charr forms from the Kamchatka River basin (stone charr, white charr, and Dolly Varden) are presented. The paper analyzes the food preferences of the fishes according to their stomach contents and retrospectively assesses their nutrition according to the ratio of stable nitrogen isotopes. The three charr forms are compared in terms of the head shape and structure of the cartilaginous skull for the first time. The correlation between the type of their nutrition and structural features of their skull is shown. Both general and specific adaptive features of the morphology of piscivorous stone and white charrs are revealed in comparison with benthivorous Dolly Varden.