DEVELOPMENT AND OCCURRENCE OF LARVAE AND 



JUVENILES OF THE ROCKFISHES SEBASTES CRAMERI, 



SEBASTES PINNIGER, AND SEBASTES HELVOMACULATUS 



(FAMILY SCORPAENIDAE) OFF OREGON' 



Sali.y L. Rhhardson^ and Wayne A. Laroche^ 



ABSTRACT 



Developmental series of larvae and juveniles of" three species of northeast Pacific rockfishes (Scor- 

 paenidae; Sebastes) are illustrated and described: iS. crarnen (8.0 to 130.5 mm standard length). S 

 pinniger (7.8 to 181 mm standard length), and S ht'luornaculatus (7.7 to 183 mm standard length). The 

 descriptions include a literature review, characters used for identification including meristics and 

 supraocular spine patterns, distinguishing features, general development, morphology, fin develop- 

 ment, spmation, scale formation, and pigmentation Occurrence in waters off Oregon is discussed. 



The approach that was used Uy identify larval and juvenile specimens o( Sebastes from plankton, 

 midwater trawl, and bottom trawl collections from Oregon waters is presented, since 36 species 

 reportedly occur there. Developmental terminology is newly defined for Sebastes. Larval and juvenile 

 spination is presented schematically and defined. 



Larvae and juveniles of the three species described here are compared with other known Sebastes 

 larvae and juveniles from the northeast Pacific 



Data gathered during this study extend the southern range limit of Sebastes emphaeus to Punta 

 Gordo, Calif 



Rockfish of the genus Sebastes are an important 

 group of fishes in the northeast Pacific both in 

 terms of number of species and in commercial and 

 sport fisheries. Sixty-nine species of Sebastes 

 occur between the Gulf of California and the Gulf 

 of Alaska (Chen 1971, 1975). In 1975, Pacific trawl 

 landings of Sebastes spp. in the United States and 

 Canada, categorized as "Pacific ocean perch" and 

 "other rockfish," were 17,400 metric tons (t) or 

 23.9% of the total trawl landings (Verhoeven 

 1976). In California, rockfish compose half the 

 number of sportfish caught (Young 1969). 



"Pacific ocean perch" (primarily Sebastes 

 alutus) trawl landings in the United States and 

 Canada declined from a peak of 14,000 t in 1965 to 

 8,500 t in 1975 and "other rockfish" landings sub- 

 sequently increased from 8,600 t in 1965 to 16,300 

 t in 1973 and 13,300 t in 1975 (Pacific Marine 

 Fisheries Commission 1964-76; Verhoeven 1976). 



'From a final report for NCAA NMFS Contract No. 03-6- 208- 

 35343 submitted to Northwest and Alaska Fisheries Center. 

 National Marine Fisheries Service, NOAA, 2725 Montlake 

 Boulevard East, Seattle, WA 98112. on 15 June 1977. 



^School of Oceanography. Oregon State University. Corvallis. 

 Oreg.; present address: Gulf Coast Research Laboratory. P.O. 

 Drawer AG. Ocean Springs, MS 39564. 



^School of Oceanography, Oregon State LIniversitv. Corvallis. 

 OR 97331. 



Manu.scnpt accepted Augu.'it 197K 



FISHERY BULLETIN: VOL. 77. NO. 1. 1979. 



Because of this shift in composition of trawl land- 

 ings, knowledge of the biology of the individual 

 species involved, including their early life history, 

 is becoming increasingly important. Such infor- 

 mation is relatively scarce, partly because of the 

 difficulty involved in identifying the young stages. 



Rockfish larvae, which are e.xtruded live from 

 ovoviviparous females, are pelagic as are young 

 juveniles. The pelagic larvae are very abundant, 

 ranking third or fourth in annual larval fish 

 abundance off California (Ahlstrom 1961, 1965) 

 and second only to osmerid larvae off Oregon 

 (Richardson 1977; Richardson and Pearcy 1977). 

 Juveniles are important as forage items for larger 

 fishes, such as albacore (Powell et al. 1952) and 

 salmon (Whitney 1893; Silliman 1941; Pritchard 

 and Tester 1944; Merkel 1957), and marine birds 

 (Follett and Ainley 1976). 



Pelagic larvae and juveniles of relatively few of 

 the 69 northeast Pacific rockfish species have been 

 described. Illustrations or partial descriptions of 

 pigment patterns have been presented for preex- 

 trusion or newborn larvae of 47 of these species but 

 only 26 of these were reared to the point of yolk 

 absorption (Table 1). The first larval developmen- 

 tal series of Sebastes spp. were presented as two 

 unnamed .species (Ahlstrom 1965) the second of 



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