FISHERY BULLETIN: VOL. 70, NO. 3 



Table 6. — Total numbers of Sebastes macdonaldi larvae taken on 14 CalCOFI lines for 4 years (1953, 1960, 1965, 

 and 1966) and abundance of larvae of this species compared with the total numbers of Sebastes larvae taken in 

 hauls containing S. macdonaldi. 



CalCOFI 

 line 



Latitude' 



Total 

 number 

 stations 

 occupied 



Total stations 



containing 

 S. macdonaldi 



Percentage of 

 positive stations 

 to total stations 



Number of 



S. macdonaldi 



larvae 



Total number of 



Sebastes larvae in 



hauls containing 



S. macdonaldi 



Percentage S. macdonaldi 



larvae of total Sebastes 



larvae in hauls positive 



for S. macdonaldi 



3 



25 



4 



4 



5 



8 



16 



30 



33 



25 



57 



37 



92 



87 



'- Latitude of most shoreward station of each CalCOFI line. 



They attain their largest numbers from line 117 

 to line 127 (Cedros Island to San Hipolito Point) 

 and then decrease to line 137. In contrast, for 

 those hauls containing S. macdoiwAdi, the ratio 

 of this species to the total number of Sebastes 

 larvae in these hauls increases continuously 

 southward. Sebastes larvae were not taken on 

 lines south of 137, probably because of the in- 

 frequent occupancy of these lines. Reproduc- 

 tion of S. macdo7ialdi occurs as far south as 

 Morgan Bank (between lines 147 and 150), since 

 one of the two specimens collected there was a 

 term female with viable larvae. 



The seasonal abundance and size of S. mac- 

 donaldi larvae at all CalCOFI stations during 

 1953 and 1960 are shown in Table 7. Larvae 

 began to appear in January, increased in num- 

 bers in February, and reached a peak in March. 

 Abundance declined progressively from April 

 to June. The mean length of the larvae increased 

 slightly during the 6-month period and the 

 largest larvae were collected from March to June. 



The larval stage is ended at about 16 mm; 

 indeed, a 15.4-mm specimen is already beginning 

 to develop the juvenile melanophore pattern and 

 the juvenile arrangement of cranial spines. The 

 pelagic. juveniles are rare in plankton collections, 

 probably because of their ability to avoid plank- 

 ton nets. Also, they may occur deeper than 

 140 m, the usual maximum depth of CalCOFI 

 plankton tows. Nevertheless, a number of pe- 

 lagic juveniles, 22.6 to 44.4 mm long, were cap- 

 tured by plankton net, midwater trawl, and dip 

 net. These are listed in Table 1 and discussed 

 in the previous section of the paper. The smal- 

 lest juvenile collected by bottom trawl was 

 59.3 mm. This suggests that the transition from 

 pelagic to demersal habitat occurs in the size 

 range of about 45 to 60 mm. Demersal juveniles 

 60 to 100 mm are captured typically at a depth 

 range of 80 to 100 m. With further growth they 

 appear to seek deeper habitats as there is a trend 

 for larger fish to be collected from greater 

 depths. The largest specimen examined (532 



Table 7. — Numbers (A), mean length in mm (B), and size range in mm (C) of Sebastes macdonaldilarvae taken 

 during 2 years of the California Cooperative Oceanic Fisheries Investigations (CalCOFI). 



956 



