FISHERY BULLETIN VOL 77, NO. 1 



the year, yellowfin tuna fishing is unregulated. 

 After a quota is reached (Table 1), all yellowfin 

 tuna fishing, except for special allowances must be 

 outside the Commission's Yellowfin Regulatory 

 Area (CYRA) (Figure 1). Due to special rules (see 



Table l. — Yellowfin quota (thousands of short and metric tonsi. 

 closure data, and annual total catch (thousands of short and 

 metric tons) for the Commission's Yellowfin Regulatory Area, 

 taken from Calkins ( 1976).' Metric tons are given in parenth- 

 eses. 



The 1976 fishrng year (through August 

 . 33rd meeting of the Inter-American Tropical 



'Calkins. T P 1976 

 30) Background Paper No 

 Tuna Commission 



^The Director ot lATTC may increment the established quota, allowing more 

 yellowlm tuna to be caught 



Figure l. — Eastern tropical Pacific fishing area divided into 

 three nearshore areas lAreas l-3i and one offshore area (Area 4). 

 The heavy line to the west delimits the boundary' for the Com- 

 mission Yellowfin Area (CYRA). The average number of 

 flotsam- associated sets from 1972 to 1975 by 5" squares is shown. 

 Data represent the unregulated fishing period isee text). 



Inter-American Tropical Tuna Commission 

 1967-1975), any detailed reporting of regulated 

 data would compromise the confidentiality of the 

 data; hence, only unregulated catch and number of 

 sets within the CYRA summarized by month and 

 5' square for 1963-75 were made available to me. 



The total number of unregulated sets during the 

 13 yr was approximately 161,000 of which 8,190 

 were associated with flotsam. In addition, the 

 lATTC provided the total number of flotsam- 

 associated sets occurring each year ( Figure 2 ). One 

 sees that the major trends in the number of sets 

 are contained in the block of unregulated data. 



NOAA's Southwest Fisheries Center (SWFC) 

 periodically sends technicians aboard tuna sein- 

 ers. These technicians record details about set 

 type, catch, environmental conditions, as well as 

 the fork length (centimeters) of tuna sampled from 

 individual sets. Fork lengths of yellowfin and skip- 

 jack tuna wereonly available for a limited number 

 of sets made in 1973-75. The location of fork length 

 measurements are given in Table 2. Single set 

 catch data were collected by SWFC technicians in 

 1974-76 (unpubl. data^). 



^Unpubl. data on file at the Southwest Fisheries Center. Na- 

 tional Marine Fisheries Service, NOAA, P.O. Box 271, La Jolla. 

 CA 92038. 



2,000 - 



1963 1965 1967 1969 1971 1973 1975 

 YEAR 



Figure 2. — Total number of flotsam-associated sets made in the 

 eastern Pacific and number of unregulated flotsam-associated 

 sets made in the CYRA, 1963-75. 



148 



