FISHERY BULLETIN: VOL 79, NO. 3 



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Figure 4. — Seasonal changes in tissue lipid content calculated 

 for the standard deep-sea scallop (120 mm shell height). • = 

 female; o = male. 



hydrate fell from late spring through September. 

 Although present at lower amounts than in the 

 gonadal mass and digestive gland, lipid in the 

 quick component of the adductor muscle rose in 

 the spring-summer and dropped in the autumn- 

 winter. 



Changes in caloric equivalents (kilocalories) of 

 energy reserves from each tissue, presented in 

 Figure 6, reflect the changes in lipid storage in 

 both the gonadal mass and digestive gland, and 

 fluctuations of carbohydrate in the quick compo- 

 nent of the adductor muscle. Differences in energy 

 reserves between the sexes are not significant, 

 although females tend to show higher levels and 

 greater fluctuations in energy content throughout 

 the year. The drop in gonadal caloric equivalents 

 in mid-September, in addition to the drop in GMI 

 and gonadal dry weight, is indicative of spawning 



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Figure 5. — Seasonal changes in tissue carbohydrate content 

 calculated for the standard deep-sea scallop (120 mm shell 

 height). • = female; o = male. 



within the population and is corroborated by the 

 histological appearance of the gonads. 



DISCUSSION 



Of the three tissues which contain appreciable 

 reserves of either lipid or carbohydrate, only 

 digestive gland and adductor muscle may properly 

 be considered "storage organs" (i.e., temporary 

 repositories of energy -rich substances which may 

 later be utilized to meet either metabolic or 

 reproductive demands). Energy-rich substances 

 within the gonad, albeit temporary, are ultimately 

 destined for gamete production and nourishment 

 of the developing larvae. If these substances are 

 completely lost at spawning, as is evident for 

 P. fnagellanicus, they should not be considered 

 as energy reserves for the adult scallop (Giese 

 1966), even though resorption of gametes by some 



454 



