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Fishery Bulletin 103(1) 



Number of bands (age) of reader one 



Figure 2 



Age bias graph for pair-wise comparison of 224 thorny skate 

 {Amblyraja radiata) vertebral counts by two independent readers. 

 Each error bar represents the 95% confidence interval for the 

 mean age assigned by reader 2 to all fish assigned a given age by 

 reader 1. The diagonal line represents the one-to-one equivalence 

 line. Sample sizes are given above each corresponding age. 



monthly increment growth that peaked in July, followed 

 by a large decline in August (Fig. 4). Based on this 

 information, the increment analyses support the likeli- 

 hood that a single opaque band may be formed annually 

 on vertebral centra during August or September. The 



marginal analysis was only conclusive for juvenile-size 

 animals (skates s80 cm TL). As thorny skates matured, 

 their growth slowed dramatically and the band counts 

 in older specimens became compressed, making it dif- 

 ficult to discern monthly changes in margin width. 



