Table <+. — Estimates of egg production of 20 species of Sebastodes 



SPAWNING SEASON 



Some information on the spawning season 

 can be had from data on the collection of 

 Sebastodes larvae in plankton net hauls (table 

 5) in the survey area of CalCOFI (California 

 Cooperative Oceanic Fisheries Investiga- 

 tions)- -Oregon to the southern tip of Baja 

 California-.for 1950-57 (Ahlstrom, 1952, 1953, 

 1954, 1958,1959; Ahlstrom and Kramer, 1955, 

 1956, 1957). The species of larvae were not 

 separated; as a group they constituted 7.6 

 percent of all larvae taken (average for 1955, 

 1956, and 1957). Their numbers were ex- 

 ceeded only by the larvae of northern anchovy 

 ( Engraulis mordax) and Pacific hake ( Mer- 

 luccius productus ). In 1950-52, the number of 

 Sebastodes larvae per haul averaged 13.9 

 and the peak of larval abundance was in 

 April (2 years) and March (1 year). In the 



following 5 years Sebastodes larvae per haul 

 averaged 25.1 and the peak of larval abun- 

 dance came earlier, in February (4 years) 

 and January (1 year). Rockfish clearly tend 

 to spawn in winter; during the 8 years, the 

 first 4 months of the year accounted for 68 

 percent of all Sebastodes larvae taken. 



Other studies have also indicated that rock- 

 fish tend to spawn primarily in winter. Fitch 

 (1958) recorded the hatching season of Se- 

 bastodes paucispinis as December through 

 April and of S. miniatus and S. serrnoides as 

 December through March. Wales (1952) gave 

 the hatching season of S. mystinus as Novem- 

 ber through March, Clemens and Wilby (1949: 

 206), referring to young Sebastodes along 

 the Canadian Pacific coast, stated, "These 

 are less than 1/2 inch in length and are 

 produced in large numbers during the sum- 

 mer months," 



