SOME METAZOAN PARASITES OF THE 

 EASTERN PACIFIC SAURY, COLOLABIS SAIRA 



Steven E. Hughes' 



ABSTRACT 



Parasite composition of the eastern Pacific saury, Cololabis saira, and severity of infections 

 were investigated to determine their possible effects on potential food fish markets and to 

 assist in determining population structure of the stock. Infection data from two copepods and 

 one acanthocephalan are presented and examined for host dependent factors, temporal and 

 spacial variation, and variation between saury with different scale features (hypothesized 

 spring- and autumn-born fish). The acanthocephalan infecting saury was also identified in 

 the steelhead trout, Salmo gairdneri, which is reported as a second definitive host. It is 

 concluded that because of parasites, only 30 to 60*7^ of marketable-sized saury occurring 

 off the Washington-Oregon coast would be acceptable as fresh-food fish sold in the round 

 although most would be acceptable as canned products. The parasite data do not indicate 

 that fish with the two different patterns of growth on the scales are independent sub- 

 populations. 



The eastern Pacific saury, Cololabis saira, is a 

 pelagic teleost occurring in offshore waters 

 along the Pacific coast of North America. 

 Although previously recognized mainly as a 

 food source for albacore, Tluoinus alalunga, the 

 saury resource in the eastern Pacific attracted 

 the interest of foreign and domestic fishermen 

 during the late 1960's. Potential domestic 

 markets included fresh, frozen, and canned 

 products for human consumption. Studies to 

 determine the parasite composition and severity 

 of infections, believed an important con- 

 sideration in assessing the potential value of 

 saury as a food fish, were undertaken by the 

 National Marine Fisheries Service at the North- 

 west Fisheries Center. Parasite data were also 

 examined for their possible use in determining 

 the population structure of saury in the sampled 

 area. Preliminary growth and scale studies 

 (Hughes, in press; Mosher-) suggested two 

 spawning groups of saury, spring- and autumn- 

 born. 



' Northwest Fisheries Center, National Marine Fisheries 

 Service, NOAA, 2725 Montlake Boulevard East, Seattle, 

 WA 98112. 



^ Mosher, K. H. Age determination procedures for 

 saury {Cololabis .saira) from the northeastern Pacific Ocean, 

 using scales. Manuscr. in preparation. Northwest Fish. 

 Cent., Natl. Mar. Fish. Serv., NOAA, Seattle, Wash. 



Initial samples collected off California in 1969 

 and limited information from two previous 

 reports (Eberhardt, 1954; Sokolovskii, 1969) 

 indicated that the eastern Pacific saury were 

 primarily parasitized by two species of copepods 

 and one acanthocephalan. Results of a detailed 

 study by Baeva (1970) indicated the eastern 

 Pacific saury are infected by at least 10 species 

 of parasites. Eberhardt reported the copepod 

 Pouiella sp. parasitized more than 20% of 250 

 saury captured off California in 1950-52. 

 Although several Peiniella species infecting 

 marine fish have been described and partial 

 life histories determined, detailed work on the 

 saury parasite appears lacking. My preliminary 

 studies and a recent Soviet study by Sokolovskii 

 indicated that up to 90% of the eastern Pacific 

 saury were infested by the copepod Caligns 

 luacarovi Gussev. This copepod also infects the 

 western Pacific saury, but Sokolovskii and 

 Baeva reported that Pennella sp. is peculiar to 

 the eastern Pacific stock. The acanthocephalan 

 detected in the preliminary studies was described 

 by Laurs and McCauley (1964) as a new species, 

 Rhadiiiorhy)ichi(s cololabis. Further reports on 

 this species also appear lacking. 



This report presents data on the numbers and 

 incidence of infestation for Pennella sp., Caligus 



Manuscript accepted February 1973. 

 FISHERY BULLETIN: VOL. 71, NO. 4, 1973 



943 



