Correlation among dominance status, metabolic rate and otolith size in masu salmon

In spatial competition between individuals, neither fish sex nor body mass affected dominance status in masu salmon Oncorhynchus masou. In contrast, resting metabolic rate (M-R) was significantly correlated with dominance status, indicating that a high metabolic rate can increase the dominance rank of juvenile salmon. Whole animal growth rate was significantly correlated with M-R, but not with initial body weight. This suggests that the body size of masu salmon is not a cause, but rather a consequence, of dominance status which is closely related to M-R. The increment width between otolith daily rings was also significantly correlated with M-R. Thus, the size of the otolith may indicate the degree of M-R. (C) 1998 The Fisheries Society of the British Isles.