Residential form of white-spotted char <Emphasis Type="Italic">Salvelinus leucomaenis</Emphasis> inhabiting the warm stream discharging into Semlyachikskii Firth (Kronotskii natural reserve,Kamchatka)

Residential form of white-spotted char Salvelinus leucomaenis appears in volcanic stream characterized by stable water and temperature regime. The maximal body length of fish is 285 mm and body mass is 245 g; the oldest specimen is 7 years old. The somatic growth does not relax, and the annual growth rate is 30–40 mm. The maturation begins at the age of 4 years after the fish reaches 175 mm length and 60 g in weight. The spawning takes place in autumn. Sex dimorphism and nuptial coloration are not observed, and the “spotted” coloration remains through the year. Vomer is toothless, or only one tooth is presented (in 15% of sampled specimens). Sagittal otoliths are characterized by deformation granular texture of ventral area, the layering is broken. The food spectra of a mature specimen comprises gammarids, large-size larvae, and imagoes of amphibiotic insects during the summer period.