FISHERY BULLETIN: VOL. 86, NO. 3 



tion. Their relationship with the SE-NHR seamount 

 populations is unknown. 



The most common pelagic occurrences (1955-87) 

 were fish ranging from 18 to 26 cm SL; smaller sizes 

 are poorly represented, probably because of the 

 nature of the sampling gear. Smaller specimens 

 were generally captured with plankton nets (Fedo- 

 sova and Komrakov 1975; Borets and Sokolovsky 

 1978), dip nets (Honma and Mizusawa 1969; Ran- 

 dall 1980; Fujii'*), and in one case, in a whale stomach 

 (Kawamura 1982). The sea-surface temperatures at 

 which the specimens were captured ranged from 

 8.6° to 15.0°C (average 12.1°C). For all years, 

 pelagic captures were restricted to the eastern 

 North Pacific, with the exceptions of larvae or early 



juveniles captured near the spawning centers at the 

 seamounts (Komrakov 1970; Table 2), over 20 

 specimens in a Bryde's whale stomach in 1979 

 (Kato^, Fig. 2B), and two individuals captured in 

 1986 at long. 155°E (Fig. 2). This is despite exten- 

 sive sampling in the western North Pacific, par- 

 ticularly by the Japan Marine Fishery Resource 

 Research Center (JAMARC) and the Hokkaido 

 University, and in the Bering or Okhotsk Seas (Table 



1). 

 Pelagic captures in the 1950's were sporadic, but 



several fish were taken north of lat. 50°N, especially 



in 1958 (Fig. 2 A). Relatively few were captured in 



the 1960's, with the exception of July through early 



August 1969, when the armorhead was an impor- 



*E. Fujii, Nippon Luther Shingaku Daigaku, Tokyo, Japan, pers. 

 commun. July 1987. 



^H. Kato, Whales Research Institute, Tokyo, Japan, pers. 

 commun. December 1987. 



Table 2. — Pelagic specimens of armorhead, Pseudopentaceros wheeleri, for which sizes were 

 available. The growth curve from Uchiyama and Sampaga (text footnote 3), based upon 

 enumeration of daily growth increments, was used to deduce age from length. For the youngest 

 fish (bottom), average readings from daily growth increments, rather than the growth curve, 

 were used. Data are from various published sources and collections listed in Table 1 . (SST 

 = sea-surface temperature.) 



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