Author: Sanger, 1984
FBname: Twospine blackfish
Comments: Occur in cool, clear streams with rocky bottoms in mountain terrain (Ref. 33616); with fast to moderate flow (Ref. 44894).  Often abundant at altitudes of 200-700 m (Ref. 33616).  Benthic,  nocturnally active species which usually occur solitary.  Juveniles often found in large groups among leaf litter and wood debris.  Movements are restricted to a relatively small stretch of river over the duration of the life span.  Occur with <i>G. marmoratus</i> at lower elevations, but they have different habitat preferences.  Feed on insect larvae, fishes, fish eggs, earthworms and crustaceans.  Breed between October and December.  Sexual maturity is attained after 2 years (Ref. 44894).  Often caught by recreational fishers targeting trout, although not a desirable target due to its small size (Ref. 33616).