extending from Karafuto and Hokkaido in the north to Formosa in the 
south "%» in the Pacific, the Japan Sea and the China Sea. The coasts 
of Nagasaki, Hyogyo, Shizuoka, Chi ha, Fukushima, Miyagi, Iharaki, Iwate 
and Aomori prefectures and Hokkaido are noted for large catches (Figure 5)* 
The fishing grounds are in general within thirty miles of shore. Much 
of the catch is taken by the coastal fisheimen, but part is taken by 
large-scale operations and is classed with the deep sea fisheries. 
Sardine fishing is carried on all year round with, however, 
different seasonal peaks in various localities. Figure 6 summarizes the 
seasons for the chief producing areas in the coastal waters of Japan 
proper. 
In the waters farther offshore large schools of sardines migrate 
with considerable regularity: in the spring the migration is northward 
with the warming waters; later, they reverse their migrations. The 
swimming layer is deeper in the southern waters, vazying from south to 
north with the thickness of surface warm layers. The large schools are 
recognized by the dark brown color effect on the water surface; where 
they swim at great depths, their wake is indicated by tiny bubbles of 
air. Their predators — mackerel, tuna and other Sccabroids are 
also signs of their presence. 
The Scombroids . These are predatory pelagic species having vast 
oceanic distribution and gathering into relatively small schools to feed. 
In general the Japan Sea is poor in Scombroids and they are virtually 
unknown in the Inland Sea. In waters off the east coast, however, they 
- 36 - 
16-03!. P58 bu 
