200 



Fishery Bulletin 104(2) 



there is a general linear increase of catch with latitude. 

 Fishing effort was concentrated in the 22-23°N and 

 23-24°N areas. Both account for 48% of the total capture 

 for the 10-year period in this region. From 18° to 21°N, 

 catch values averaged 12.9% of the total catch. 



Yellowfin tuna catches affected by ENSO events 



Sea surface temperature anomalies (SSTA) were used to 

 investigate the effect of interannual warming or cooling 

 events on the variability of YFT catch. Anomalies for 



D Sets 

  Catch 



? 20- 



mm 



18-19 19-20 20-21 21-22 22-23 23-24 



Latitude ('N) 



Figure 3 



Latitudinal distribution of catches of yellowfin tuna ^Thunnun albacares] 

 for the period 1990-99. 



p 

 w 



CO 



2 

 



-2 



4 



2 







-2 



2000 



c 



2 1000 



-1000 



SW 



MW Cold 



SW 



Cold 



^4 ^. 



1 I i " 



I ^1 



1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 



Figure 4 



Sea surface temperature anomalies (SSTAs) in the El Nino region 3 (A), 

 SSTAs in the study area (B) and catches of yellowfin tuna tThunnus alba- 

 cares) (C). Bars at the top show the equatorial central Pacific episodes as 

 compiled by the Climate Prediction Center (see "Methods" section): Strong 

 warm (SW) peaks of catch are indicated by thin vertical lines. Thick verti- 

 cal lines indicate maximum SST anomalies in NIN03 (A). Dashed vertical 

 lines indicate peaks of SSTA in the area of study (B). Moderate warm (MW) 

 and cold episode. The maximum intensity of the warm episodes is marked 

 with dashed lines (B and C). 



