A Preliminary Report on Parathunnus sibi in Hawaiian Waters 
and a Key to the Tunas and Tuna-like Fishes of Hawaii 1 
Vernon E. Brock 2 ' 
The bigeye tuna, Parathunnus sibi (Temm- 
nick & Schlegel), is an important part of the 
catch of large tunas from Hawaiian waters 
(Table 1), and yet it is so little known that it 
seems desirable to publish the preliminary data 
obtained by the Division of Fish and Game of 
Hawaii concerning it. These data may be con- 
veniently considered in three categories: (1) 
field identification of the species principally by 
external characters, (2) morphometric data, 
which may be useful in later racial studies as 
the species is an important one in Japanese as 
well as Hawaiian landings (Shapiro, 1948: 
Table 8 ) , and ( 3 ) some ecological information 
based largely on the characteristics of the fishery 
for the species in Hawaii. Some incidental in- 
1 Research Paper No. 8, Cooperative Fisheries Re- 
search Staff, Territorial Board of Agriculture and 
Forestry and the University of Hawaii. Manuscript 
received December 10, 1948. 
2 Director, Division of Fish and Game, Board of 
Agriculture and Forestry, Honolulu, Hawaii. 
formation on the commercial importance of this 
species and on the method of taking it is also 
given. 
Parathunnus sibi has been reported from Ha- 
waiian waters by Kishinouye (1923: 444), 
Jordan and Evermann (1926: 17), and Fowler 
(1928: 134). Kishinouye’s report was hearsay 
and the descriptions by Jordan and Evermann 
and by Fowler are hardly sufficient for certain 
identification. Based on a single sight identifica- 
tion in the San Pedro markets, Kishinouye also 
reported the occurrence of this species on the 
west coast of North America. Since then Godsil 
and Byers (1944: 105-119) have discussed in 
detail two small specimens from the west coast 
of Central America. P. sibi, originally described 
from Japanese waters, would seem to span the 
tropical Pacific in its range. 
In the spring of 1948, during a morphometric 
study of Hawaiian yellowfin tuna, Neothunnus 
TABLE 1 
Landings of Yellowfin and Bigeyed Tuna in the Territory of Hawaii, 1947 and 1948 
MONTH 
YELLOWFIN 
BIGEYED 
1947 
1948 
1947 
1948 
pounds 
pounds 
pounds 
pounds 
January. 
58,277 
87,661 
14,496 
64,434 
February. ............................. 
70,494 
92,664 
24,079 
108,374 
March ................................ 
21,955 
88,671 
28,472 
78,065 
April. ................................ 
89,652 
72,469 
24,176 
78,739 
May. ................................ 
86,843 
60,209 
13,661 
40,407 
June. ................................ 
161,988 
123,014 
10,086 
26,644 
July. ................................. 
173,673 
130,005 
14,858 
19,761 
August ............................... 
197,949 
132,629 
15,646 
15,616 
September ............................ 
139,831 
96,162 
7,077 
21,835 
October ............................... 
101,675 
71,703 
14,455 
40,808 
November. ........................... 
95,396 
102,483 
62,393 
76,526 
December ............................. 
116,616 
100,441 
101,269 
99,128 
Totals .............................. 
1,314,349 
1,158,111 
330,668 
670,337 
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