size (in relation to size at maturity) and exploita- 

 tion rates in the fishery. In a fishery with a small 

 minimum legal size and high exploitation rates, 

 most of the ovigerous females in the population 

 would be small animals laying for the first time. 

 The incidence of new-shelled ovigerous females 

 in autumn sampling at Arnold's Cove has ranged 

 from to 38.5% of the total ovigerous specimens 

 examined (Table 1). This year-to-year variability, 

 which has also been observed elsewhere in New- 

 foundland (Ennis 1980), could be accounted for by 

 variation in relative abundance of prerecruit ani- 

 mals caused by annual fluctuation in recruitment 

 and exploitation rate. 



TABLE 1. — Percentage of ovigerous lobsters with new shells in 

 autumn sampling at Arnold's Cove, Newfoundland, 1975-82. 



tions of lobsters, Homarus americanus. Fish. Bull. 

 U.S. 82:244-249. 



G. P. ENNIS 



'These are postmolt carapace lengths 



2 Diver-caught samples obtained during the same period as the trap-caught 

 samples. 



Acknowledgments 



I am indebted to R W. Collins and G. Dawe 

 who, with assistance from other technical staff 

 and casual employees, carried out the field work 

 and data processing associated with this study. 



Literature Cited 



AIKEN, D. E., AND S. L. WADDY. 



1976. Controlling growth and reproduction in the Amer- 

 ican lobster. Proc. 7th Annu. Meet. World Mariculture 

 Soc, p. 415-430. 



1980. Reproductive biology. In J. S. Cobb and B. F. 

 Phillips (editors), The biology and management of lob- 

 sters, Vol. I, Physiology and behavior, p. 215-276. Acad. 

 Press, N.Y. 

 ENNIS, G. P. 



1978. Growth curves for Newfoundland lobsters from data 

 on molt increment and proportion molting. Research 

 Document 78/29, Canadian Atlantic Fisheries Scientific 

 Advisory Committee, Halifax, Canada, 11 p. 



1980. Size-maturity relationships and related observa- 

 tions in Newfoundland populations of the lobster (Homa- 

 rus americanus) . Can. J. Fish. Aquat. Sci. 37:945-956. 



1984. Comparison of physiological and functional size- 

 maturity relationships in two Newfoundland popula- 



Fisheries Research Branch 



Department of Fisheries and Oceans 



P.O. Box 5667 



St. John's, Newfoundland, Canada A1C 5X1 



PARASITES OF OLIVE ROCKFISH, 



SEBASTES SERRANOIDES, (SCORPAENIDAE) 



OFF CENTRAL CALIFORNIA 



The olive rockfish, Sebastes serranoides, inhabits 

 reefs from Del Norte County, Calif., to San Benito 

 Island, Baja California, Mexico. Olive rockfish are 

 large (to 64 cm TL), active predators, usually 

 found in the water column, but occasionally hover- 

 ing over or resting upon rocky substrates. 

 Juveniles are primarily midwater feeders, preying 

 upon zooplankton and small fishes, though some 

 demersal feeding (e.g., isopods, caprellid and 

 gammarid amphipods, etc.) has been noted (Hob- 

 son and Chess 1976; Love and Ebeling 1978; Love 

 and Westphal 1981). Adults feed almost entirely on 

 nektonic forms of squid and fish and on substrate- 

 dwelling octopus (Love and Westphal 1981). 



Little is known about the parasite fauna of olive 

 rockfish, as previous reports are either descrip- 

 tions of newly discovered species (Cressey 1969; 

 Moser and Love 1975; Love and Moser 1976; Moser 

 et al. 1976) or surveys of particular parasites 

 throughout a fish community (Turner et al. 1969; 

 Hobson 1971; Dailey et al. 1981). As part of a life- 

 history study, we investigated the parasite popula- 

 tion of central California olive rockfish. 



Methods 



Specimens were collected monthly from April 

 1975 to February 1976 at a group of shallow- water 

 pinnacles, about 11 km west of Avila Beach, San 

 Luis Obispo Co., Calif., (Fig. 1). These pinnacles, at 

 depths of 20-30 m, are situated 100-300 m offshore 

 from Diablo Cove and North Cove and rise to 

 within 5-10 m of the surface. 



Six hundred olive rockfish, ranging from 8.6 to 

 49.2 cm TL, were collected by hook and line or 

 spear, placed in plastic bags, and frozen for later 

 dissection. After thawing, each specimen was 



530 



FISHERY BULLETIN: VOL. 82, NO. 3, 1984. 



