FISHERY BULLETIN: VOL. 86, NO. 3 



Figure 4.— Distributions of benthic and pelagic specimens of armorhead, Pseudopentaceros wheeleri, by age group with possible 

 patterns of movement. Area A represents the major spawning area, and area E the region inhabited by the large, older specimens. 

 Area B is the region in which specimens younger than 1 year have been captured, and area C where fish from 1 to 2 years old 

 have been captured. The arrow through this region represents the main population movement pattern. Other arrows represent 

 possible movements for stray fish. Areas marked D and F represent locations of benthic collections from California and Japan, 

 respectively. 



Islands (area E in Figure 4) are typically larger than 

 those in the normal part of the range and are corre- 

 spondingly older, with ages estimated at 4 or 5 years 

 (Humphreys et al. in press), similar to the time sug- 

 gested for a circuit of the gyre by McNally et al. 

 (1983). 



The other plausible movement pattern can be used 

 to explain the existence of specimens in Japan. Ben- 

 thic specimens of armorhead are rarely captured in 

 Japan (Fig. 1); a report of 3,000 t landed in 1969 

 by Soviet fishermen in this region (Abe 1969) may 

 be in error, since the Soviet fishery on the SE-NHR 

 seamounts developed heavily that year (Borets 1975) 

 and SE-NHR fish were likely sold in Japan. The 

 reproductive condition of these animals is not 

 known, so the source of the spawning population 

 supplying them is at question. The large, reproduc- 

 tive individuals in area E (Fig. 4) have been found 

 as far south as lat. 23°43'N (Humphreys et al. in 

 press). It is possible that larvae and juveniles are 

 transported to Japan in the northern part of the 

 North Equatorial Current (Uda and Hasunuma 



1969). This is consistent with the capture of over 

 20 fish in a Bryde's whale stomach in September 

 1979 at lat. 26°N (H. Kato fn. 5; Fig. 2B). Subse- 

 quent captures of this species have not been made 

 in Japanese waters, where their presence may re- 

 quire a rare recruitment event from an upstream 

 population source, as has been suggested for sea- 

 mount populations of lobsters (Lutjeharms and 

 Heydorn 1981). These animals may also remain 

 within a gyral circulation, however, as suggested by 

 the presence of two specimens captured in the 

 Kuroshio in 1986 (Fig. 2B). 



Recruitment to the Seamounts 



The seasonal timing of the recruitment of the 

 pelagic armorhead to the SE-NHR seamounts is 

 unknown. That no records of larger pelagic fish cap- 

 tured near the seamounts (Fig. 2) exist may be an 

 artifact of sampling in inappropriate seasons or lack 

 of sampling in deeper water. The youngest benthic 

 specimens from the seamounts were slightly in ex- 



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