MacFarlane and Norton: Nutritional dynamics of embryonic-stage Sebastes 



277 



Table 3 



Estimated concentrations of lipids and protein in Sebastes flavidus and Sebastes jordani larvae at birth. S.jordani data are for all 

 populations combined and for each of three populations at Bodega, Pioneer, and Ascension submarine canyons. Values presented 

 as mean ± SD in mg/g wet weight. TAG = triacylglycerols; NEFA = nonesterified fatty acids; CH = cholesterol; PL = polar lipids. 



' Significantly greater than that for S. flavidus iP<0.0001 1. 



- Significantly less than that for S. flavidus iP<0.01 1. 



■* Greater than that for S, jordani at Pioneer Canyon (P<0.001 1, 



■• Greater than that for S jordani at Bodega and Pioneer Canyons iP<0 0001). 



tilization than did shortbelly rockfish, 225,9 

 mg/g compared with 165,0 mg/g (Table 2), At 

 birth, the estimated concentration of protein 

 in shortbellly rockfish larvae was signifi- 

 cantly greater than that in newborn yellow- 

 tail rockfish (P<0,0001); however, the total 

 lipid concentration was less (P<0,01) (Table 

 3), That shortbelly rockfish have less lipid at 

 parturition suggests they have a greater ur- 

 gency for feeding than yellowtail rockfish 

 soon after birth, or else catabolism of tissue 

 protein would be required for maintenance, 

 reducing the probability of survival. 



Energetically, lipid was the predominant 

 fuel for embryo development for shortbelly 

 rockfish, as for yellowtail rockfish. The 59.4 

 mg lipid/g embryo metabolized between fer- 

 tilization and parturition represented 2,35 

 kJ/g, and the 91,3 mg protein/g embryo rep- 

 resented 1,84 kJ/g, 



Total energy consumed for embryogenesis 

 was significantly greater in yellowtail rock- 

 fish than in shortbelly rockfish (P<0,0001), 

 The production of a gram of fully formed, 

 hatched, preborn larval yellowtail rockfish 

 required the expenditure of 7,51 kJ of energy. 

 For shortbelly rockfish, the equivalent energetic cost 

 was 4,19 kJ/g of EMS-33 larvae. Because the aver- 

 age weight of ovaries at late stages of gestation was 

 204,9 ± 16,9 g (n = 17) in yellowtail rockfish but only 

 43.4 ± 2.8 g {n-21) in shortbelly rockfish, require- 

 - ments for maternally supplied nutrients were much 

 greater for yellowtail rockfish. For comparison, the 



250 



200 



150 



Sebastes jordani 



Total Protein 



Total Lipid 



1 6 11 16 21 26 31 



Embryo maturation stage 



Figure 2 



Total lipid and protein concentrations in oocytes and embryos in fe- 

 male shortbelly roektish, Sebastes jordani . from prefertilized oocytes 

 (EMS 1) through the hatched preborn larval stage (EMS 33). Data 

 I means ± SE) from shortbelly rockfish from populations at all three 

 submarine canyons are shown. Mean number (range) of females as- 

 sayed at eachEMS was 8 (1-21). See Table 1 for description of EMS. 



mean standard length and total weight for female 

 yellowtail rockfish was 36 ± 0.5 cm and 1304 ± 55 g 

 versus 21 ± 0,2 cm and 150 ± 4 g for the shortbelly 

 rockfish assessed in this study. 



The significant difference in energy required to 

 produce a gram of larvae in the hatched, preborn stage 

 in the two rockfish species may relate to differences 



