FISHERY BULLETIN: VOL. 71, NO. 4 



method of infection, and minimal host-tissue 

 damage (Figure 3). Hotta (1962) reports that 

 tissue damaged by C. macarovi infestation is 

 limited to the epidermis and mucosa while the 

 muscle is not penetrated. 



Scars from Previous Copepod Infections 



Pacific saury were heavily scarred from 

 previous infections by Peiniella sp. and C. 



macarovi. In many cases the scar's shape clearly 

 indicated a previous C. macarovi infection, but 

 most old scars could not readily be discerned 

 between specific causes (Figure 4). Accordingly, 

 all scars were treated equally. 



The percentage of scarred fish and the average 

 number of scars per fish generally increased as 

 a function of increasing age. This is shown in 

 Table 3 where numbers and percentages of 

 scarred fish are categorized by age into three 



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Figure 3. — Pacific saury infected by the copepod, Caligus macarovi Gussev. 



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fS 



^iiiiHildiyiiiiihliiilihiiiiiiUrilutliliii 



r.,.(!'TTT1f 



Ujll{}ffitllilfl[lhl<tlfillillll)lilliiillil iLli!lilli]r|i,'il4 



Figure 4. — Examples of scars resulting from previous infections by copepods on Pacific saury. 



948 



