at'- 



CStVINCINT 



-^iMiitaiisii^^jiUiiiB 



10* 



fCtTIES 



TRAP SYMBOLS 



Figure 45. Trap fishing locations for bluefin tuna in the Ibcro-Moroccan Bay 

 area. 



the Spanish traps, provided by 

 Lozano Cabo (1958), Rodriguez- 

 Roda (1964a, 1973, 1974), and 

 Aloncle et al (1976), are believed to 

 be complete, but are somewhat bi- 

 ased by the inclusion of some records 

 of the La Linea trap, which is actu- 

 ally just inside the Mediterranean. Its 



catches, however, were relatively 

 small From four to seven Spanish 

 "Atlantic" traps were listed for 1 94 1 - 

 1971. Since then, only one or two, if 

 any, have been set. The Portuguese 

 data, provided by Vilela (1960), Lima 

 Dias and Barraca (1972) and 

 Republica Portuguesa (1957, 1958. 



Figure 46. Schematic diagram of the type of sfx;cializcd tuna trap used in the 

 Ibero-Moroccan Bay area: (a) body of trap, divided into compartments, (b) leader 

 fi"om shore to trap, (c) leader extending olTshore from trap Solid hnes show trap 

 arranged to catch fish traveling from right lo left Dashed lines show trap 

 modified to catch fish traveling from left lo right. 



1959, 1960, 1961, 1962, 1963, 1964, 

 1965, 1966, 1967, 1968, 1969, 1970, 

 1971) are believed to be complete. 

 Five traps were set in most of the 

 years 1931-1965. three m 1966-1968 

 and two in 1968-1972. Due to these 

 discrepancies and ormssions, the data 

 m Figure SO are not exact. They are 

 presented to illustrate trends in the 

 catches rather than exact totals. 



Pavesi (1889) estimated the 

 mean annual production of the Span- 

 ish traps for the penod 1884-1887 at 

 70,000 tuna, or quintals (100 kg). He 

 derived a corresponding figure of 

 30,000 tuna for the Portuguese traps. 

 Roule (1917) calculated the average 

 yearly catch of the Portuguese traps 

 in the years 1896- 191 2 at 43,983 tuna. 

 In the period from 1930 through 



1960, the Spanish catches occasion- 

 ally surpas.sed Pavesis figures, with 

 106,000 fish in 1930, 76,200 in 1943, 

 63,500 in 1944 and 80,500 in 1949. 

 The average for the period, about 

 55,000 fish per year, was consider- 

 ably below Pavesi's figure. The Por- 

 tuguese traps only attained Pavesi's 

 average of 30,000 fish in 1943, with 

 32,400 fi.sh, and never approached 

 the 1896-1912 average of nearly 

 44,000 fish. The 1931-1960 average 

 of the Portuguese fishery' was 17,400 

 fish per year The Larache group in 

 Morocco produced a peak catch of 

 29,000 fish in 1958 and averaged 

 13,500 fish per year for 1930-1960. 

 The addition of the Cape Spartel and 

 Kenitra catches would increase these 

 figures considerably Data for Mo- 

 roccan catches before 1930 are too 

 meager to permit any deductions in 

 regard to long-term trends. 



The total annual catches of the 

 samples of the three fisheries re- 

 mained above 48,000 fish and 7,000 

 tons per year through 1962. A de- 

 cline which began in 1963 became 

 disastrous after 1967. listimated 

 catches varied from 16,00(J to 24,000 

 fi.sh(2,400-4,300tons) in 1963-1967, 

 and fell to 700 to 12,600 fish (100 to 

 1,600 tons) in 1968-1973. The Por- 

 tuguese traps caught just one fish in 

 1971 (Lima Dias and Barraca 1972) 

 and only 176 kg in 1972 (Y F. 

 Barraca, personal communication). 

 They have not been set since. In 1972, 

 the only Spanish trap set in the At- 

 lantic, Barbate, which had averaged 



45 



