ICyagi Prefecture Fisheries Expei'iment Station,, Fisheries 

 Guidance Materials No, !„ March 1939 o 



Skipjack Fishing Grounds and Oceanographic Conditions 

 in the Northeastern Sea Area 



by 



Takeo Sasaki 



Contents 

 Preface Page 



(1) Surface water temperatures and the distribution 

 of skipjack fishing gromids in the Northeastern 



(2) Lines of discontinuity and distribution of skipjack 

 fishing grounds within the area of favorable water 

 temperatures in the Northeastern Sea Area, o . » c . » o . » 6 



(3) Types and density of skipjack schools and their 

 biting qualities in the Northeastern Sea Areao.c.o 9 



(ii) Sources of the skipjack schools of the Northeastern 



06cL JU/GcL oOOOOOOOiOOOOOOcOOOOOOOOOOOaOOOOPOoeooOOOOO ■■ ■* 



(5) Autumn low pressure areas and sea conditions and 

 the skipjack fishing grounds on the Northeastern 



06CL ^^£^6Cb o O OOOOCOOOOaOOOO OO^OOOUOOOOOOOOOOOO OO 00 OOOO ■■■^ 



(6) Data for the prediction of the abundance or 



scarcity of skipjack in the Northeastern Sea Areaoo 13 



(7) Skipjack landings at five fishing ports in Miyagi 



i^rsx G ctur© 000000000000000*00 0000000000000 ooooooooo© aLf 



(8) On the migrations of the skipjack schoolSoo o oo o oo oo 18 



Appendi x 



On the skipjack taken in the winter tuna longline fishery 20 



