Cottus Life History 
117 
MONTH 
Fig. 2. Mean monthly gonad weights for all C. bairdi over 45 mm TL collected 
from Straight Creek, March 1977 to April 1978. 
easily detected and fish with lost tags could be identified for population 
estimates of this size class. 
RESULTS 
Population —Length/frequency distributions of all 
sculpins collected from Straight Creek in March 1977 and March 1978 
are presented in Figure 1 and suggest that both males and females 
reproduce for the first time at the end of their second year. Mature males 
were distinctly larger than mature females in this population. Com- 
parison of the rather small samples of immatures in the March 1977 and 
