500 



Fishery Bulletin 97(3), 1999 



Spring 



H 1 1 1 h- 



Summer 



Winter 



11 



i ' M ' - M — I — \ — ^ — t-"^ 



^ — (N 



— < — CS 



^ — CN 



Depth (m) 



3.5 ,' 



3 I 



^ 2.5 • 



^ M 



M 1.5 - 



I 



0.5 



Spring 



Summer 



Winter 



^i , ^ 



F^ 



ML 



_ML 



Depth (m) 



3.5 

 3 



2.5 



Spring 



Summer 



Winter 



Zone I 



Zone II 



Zone III 



Zone I 



Zone II 

 Depth 



Zone III 



Zone I 



Zone II 



Zone III 



Figure 2 



Seasonal distribution of Pagrus pagrus abundance in different depth range.s on the Cretan 

 continental shelf. Log(A'+ll = the average logarithm of the number of individuals per nmi-. 



increased with increasing size, with 0-size-class fish 

 to exhibit the lowest consumption rate (Table 3). The 

 mean number of prey items consumed decreased sig- 

 nificantly with size {F=3.33, P<0.05) (Table 3). 



Breadth of diet decreased with fish size, both nu- 

 merically (abundance) and with bidmass of prey species 

 (Table 3). In general, values for dietary overlap between 

 size classes were similar irrespective of the resource 

 matrix used. A significantly high overlap was observed 

 only between specimens of 1 and 2 size classes (Table 5). 



Seasonal variation in diet 



Diet composition was fairly consistent over the 

 months (Fig. 5, A and B). Decapods were the most 

 important prey throughout the year, especially dur- 

 ing winter months and March, owing to the increase 

 of the importance of the thalassinid U. tipica. Poly- 

 chaetes were also an important component in the diet 

 of red porgy throughout the year. Dietary breadth 

 varied little, except for low values in winter months 



