only very occasionally brought into Suo. It was found out that there was no name applied to this 

 species and that in the market they were handled as if they were sailfish. From October to 

 December of 1936 the same vessel carried out another investigation of the same sea area and 

 took 26 specimens of this species. The research vessels Shichisei Maru of Taihoku Province 

 and Takao Maru of Takao Province, carrying out cooperative investigations in the sea areas to 

 the north and south, also took several specimens of this species, so that its distribution was 

 gradually clarified. 



There are no essential differences between the longline gear used by research vessels and 

 that used by commercial fishing boats, nor does it seem likely that the bait used is so different as 

 to cause a difference in the catch. Consequently it must be thought that the fact that this species 

 is not taken by commercial fishing boats but has been taken only by research vessels is due to the 

 fact that they operated in different sea areas. Actually, the research vessels fished from 30 

 miles to 300 miles off shore but principally at about 150 miles off the coast, while the operating 

 area of the commercial boats is restricted to a range of 30 miles from shore. Consequently we 

 can conclude that the shortnosed spearfish occurs only in the far off shore waters. Furthermore, 

 as the vessels get farther off shore they catch fewer of the large fish that are taken along the 

 coast, and even most of the fishes of the genus Makaira that they take are very small. The 

 following table gives statistics on the spearfish catch by months and by species for the Suo 

 market in 1934 and 1935. 



As is clear in the following table, in the waters east of this island the migrations of the 

 spearfishes, except for the sailfish, are entirely limited to the winter nnonsoon, while the sail- 

 fish is taken throughout the year and is always present around the island, although it is nnore 

 abundant in the summer. As will be detailed later in the section on the fisheries, from April to 

 July everywhere on the east coast of Taiwan a large nunnber of large set nets are used. The 

 manner of using these set nets differs from place to place, but because on the east coast of 

 Fornnosa the bottom falls off steeply the nets are placed very close to the shore. Sailfish are 

 occasionally taken in these set nets. Very rarely a striped marlin is also found among the catch 

 of the set nets, but for the most part the only spearfish they take is the sailfish. Consequently 

 it is thought that the sailfish has the habit of coming in very close to the coast. Other fisheries 

 also take considerable numbers of this species in the summer, a fact which it can be thought 

 shows that the distribution of this fish in the waters around Fornnosa differs completely from that 

 of other species in that it is connparatively densely present in the summer. 



If we look at the statistics for several years' landings of spearfishes in the Suo market, we 

 can see a tendency for white marlin to predominate overwhelmingly in the early part of the season, 

 with striped marlin increasing gradually in the middle of the season until they equal the white 

 marlin in numbers, and with black marlin appearing in large numbers at the end of the season. 

 The appearance of the black marlin is for only a very short period of tinne, the striped marlin's 

 season is next shortest, and the fishing for white marlin continues over a rather long tinne. Sail- 

 fish appear in considerable numbers connparatively abundantly throughout the year. According 

 to the investigations of the Shonan Maru from June to August of 1937, at this season large numbers 

 of black marlin were taken in the Kuroshio Current area of the East Philippine Sea, and it is 

 interesting to note that among the fish taken over 80 percent were male, females being very rare 

 in the catch. Furthermore, the gonads of both the females and males were very immature. The 

 larger fishing boats based at Takao operate in the vicinity of Hainan Island from April to June 

 fishing longlines for black marlin, and it is reported that among the fish taken on this fishing 

 ground there are not a few which have their gonads completely developed and are engaged in 

 spawning. 



To summarize, if we consider the occurrence and migrations of the istiophorid fishes in 

 Taiwan waters according to genera, the fishes of the genus Makaira are abundant in the winter in 

 the area of the Japan Current rather close to shore; the shortnosed spearfish we know little about 

 because there have been no investigations at other seasons of the year, but it is also abundant in 

 the winter in the Japan Current area. However, it is markedly pelagic and its occurrence is 

 limited to the far off-shore waters. The sailfish is abundant around the island throughout the year 

 but is particularly abundcint in the summer, and its migrations extend very close to the coast. 



34 



