Megalofonou et al : Incidental catch and estimated discards of pelagic sharks in the Mediterranean Sea 



631 



600 



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—I— Max Pnonace glauca 



_ Min n=3771 



I I Mean+SD 

 Mean-SD 

 o Mean 



I 



Q 



□ 



I 



SWO-LL ALB-LL BFT-LL DN SWO-LL, 



Isurus oxyrinchus 

 n=257 



1 



I 



□ 



600 



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100 



SWO-LL ALB-LL BFT-LL DN SWO-LL, 



Aloptas vulpinus 

 n=48 



I 



I 



SWO-LL ALB-LL BFT-LL DN 



Fishing gear 



SWO-LL, 



Figure 5 



Size-range variation for Prionace glauca, Isurus oxy- 

 rinchus, and Alopias vulpinus by fishing gear in the 

 Mediterranean Sea during 1998-2000. See Table 1 for 

 definitions of abbreviations for fishing gear along x axis. 



600 



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— ^ ax Prionace glauca 



Min n=3771 



CD Mean+SD 

 Mean-SD 



□ Mean 



I 



M 



T 



T 



I 



T 



Isurus oxyrinchus 

 n=257 



i 



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Alopias vulpinus 

 n=48 



I 



T 



1 23456789 



Area 



Figure 6 



Size-range variation for Prionace glauca, Isurus oxy- 

 rinchus, and Alopias vulpinus by area sampled in the 

 Mediterranean Sea during 1998-2000. See Table 1 for 

 definitions of area numbers along the x axis. 



ber in the eastern N. Atlantic and Straits of Gibral- 

 tar. Probably, certain water temperature preferences of 

 sharks during their biological cycle force them to shift 

 to shallower and warmer water masses, especially in 



summer. At these depths sharks are more vulnerable 

 to surface gears and that is reflected in higher catches. 

 Higher catch rates in late spring and summer could 

 be also attributed to juvenile recruitment (Strasburg, 



