Table 1.
Vertical size distribution in response to predation risk. (Mean size (mm;±1s.d.) of Daphnia in surface (S) and bottom (B) waters of enclosures during the summer season. MANOVA is used to test differences in Daphnia size among treatments with (VF and UVF) and without (V and UV) predatory fish in surface and bottom waters, respectively.)
| no predation | predation | |||||
|---|---|---|---|---|---|---|
| depth | V | UV | VF | UVF | ||
| June | S | 0.81(0.28) | 0.67(0.11) | 0.75(0.25) | 0.86(0.31) | F1,12=0.0; n.s. |
| B | 0.93(0.41) | 0.87(0.25) | 0.92(0.24) | 0.86(0.31) | F1,12=0.14; n.s. | |
| July | S | 1.02(0.31) | 0.99(0.27) | 0.74(0.20) | 0.73(0.07) | F1,12=17.7; p<0.001 |
| B | 1.06(0.33) | 1.34(0.38) | 1.30(0.36) | 1.20(0.28) | F1,12=0.42; n.s. | |
| August | S | 1.35(0.20) | 1.26(0.35) | 0.80(0.24) | 0.75(0.15) | F1,12=23.88; p<0.001 |
| B | 1.26(0.23) | 1.47(0.19) | 1.18(0.37) | 1.28(0.26) | F1,12=2.99; n.s. | |
| September | S | 1.19(0.34) | 1.16(0.19) | 0.92(0.28) | 0.79(0.20) | F1,12=9.77; p<0.009 |
| B | 1.18(0.19) | 1.25(0.32) | 1.17(0.30) | 1.14(0.36) | F1,12=0.17; n.s. | |