1990 Grayling Spawning Report 

 Table 1. (continued). 



Sex and state of maturity (immature; mature, but not ripe; 

 ripe; or spent) were recorded for all grayling. Sex determination 

 was based on extrusion of gametes, the ability to feel eggs within 

 the body cavity, and the shape of the dorsal fins as documented by 

 Rawson (1950). Ripeness of female grayling was difficult to 

 determine until immediately prior to and during spawning. It was 

 difficult to determine if males were spent because sperm could 

 still be extruded from spent fish. 



Scale samples were removed from grayling and scale impressions 

 were made in acetate. Scale samples were later read for age 

 determination. Age interpretation from scale samples up to age IV 

 was believed relatively accurate, while estimation beyond age IV 

 was suspect. Growth interpreted from scales should be reliable 

 because scale samples were obtained in the spring during annulus 

 formation. 



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