Diel Feeding Features of Juveniles of Two Sparids
211
Figure. Diel feeding rhythm of
D. puntazzo and S. salpa
(DWsc, dry weight of stomach
content)
011
r..f
'"
~
0,050
0,045
0,040
0,035
0.030
0,025
0,020
0,015
0,010
0,005
0,000
8am
12 am
4pm
8pm
12pm
Time (hours)
Table 1. Frequency occurrence (% Fr) and percent volume (% V) of food items in the diet of D. puntazzo
Items
Sam
12 am
4pm
8pm
12 pm
%Fr %V
%Fr %V
%Fr %V
%Fr %V
%Fr %V
Amphipoda
50.0 18.7
55.5 13.4
80.0
11.9
100.0 56.9
60.0 49.0
Ascidiacea larvae
0.0
0.0
77.8 58.2
SO.O 52.6
44.0
7.8
40.0 27.1
Bryozoa
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Copepoda
20.0
1.0
77.8
3.2
80.0
5.3
89.0 16.7
40.0
3.5
Fecal pellets
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Hydrozoa
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Isopoda
0.0
0.0
11.1 12.4
10.0 12.8
0.0
0.0
0.0
0.0
Mollusca larvae
20.0 23.1
0.0
0.0
50.0
15.4
11.0
2.6
0.0
0.0
Ostracoda
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Phycophyta
0.0
0.0
ILl
2.1
10.0
1.8
11.0
5.2
10.0
2.9
Polychaeta
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Tanaidacea
30.0 13.5
27.8
2.8
10.0
0.2
44.0
5.4
30.0 10.3
Unidentified eggs
20.0 43.7
38.9
7.9
0.0
0.0
22.0
5.4
20.0
7.2
Table 2. Frequency occurrence (% Fr) and percent volume (% V) of food items in the diet of S. salpa
Items
8am
12 am
4pm
8pm
12 pm
%Fr %V
%Fr %V
%Fr %V
%Fr %V
%Fr %V
Amphipoda
16.7
1.3
0.0
0.0
0.0
0.0
20.0
0.8
0.0
0.0
Ascidiacea larvae
16.7
0.7
30.0
2.4
80.0
67.4
20.0
7.4
40.0 11.0
Bryozoa
66.7 15.8
10.0
0.6
80.0
4.3
20.0
4.0
0.0
0.0
Copepoda
83.3
1.2
50.0
0.7
70.0.
1.9
90.0
1.0
50.0
0.7
Fecal pellets
16.7
0.3
30.0
2.2
0.0
0.0
40.0
0.3
10.0
0.2
Hydrozoa
66.7 10.7
100.0 31.2
80.0
5.3
60.0
8.0
40.0
3.4
Isopoda
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Mollusca larvae
0.0
0.0
0.0
0.0
10.0
1.6
0.0
0.0
10.0 15.3
Ostracoda
16.7
0.7
0.0
0.0
30.0
0.1
20.0
0.1
0.0
0.0
Phycopbyta
100.0 68.2
100.0 61.7
90.0
16.7
100.0 72.0
70.0 62.3
Polychaeta
16.7
0.4
10.0
0.2
10.0
0.1
40.0
0.6
10.0
0.1
Tanaidacea
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
Unidentified eggs
16.7
0.7
20.0
1.0
30.0
2.6
40.0
5.9
20.0
7.0
_. _ D. PIDIW:ZO
- a - S. salJIQ
4am
4am
%Fr %V
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
4am
%Fr %V
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0