Table 2.
Behavioural attribute and catch summary for African penguins targeting different prey assemblages (single fish prey and fish schools) during different dive types (all—all dive types combined; shallow—dives less than 5 m, deep—dives greater than 5 m) and dive phases in the presence (association—ass.) and absence (solitary—sol.) of conspecifics. For schooling prey, catch locations are relative to the fish school: escapees—disaggregated from school; school edge—fish less than 2 fish lengths of the school perimeter; school centre—fish greater than 2 fish lengths of the school perimeter. Movement behaviours, undulations and rotations, are given as the proportion of these incidents per event type. Only dives with successful catches were included in this summary.
mean (s.d.) fish caught per catch location |
movement |
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prey assemblage | dive type | dive phase | foraging mode | n dives | duration (s) mean (s.d.) | single/ escapees | school edge | school centre | undulate % | rotate % |
single | all | complete | sol. | 60 | 57.5 (30.5) | 1.6 (1.2) | — | — | 90 | 0 |
single | all | complete | ass. | 5 | 36.8 (24.8) | 1.2 (0.5) | — | — | 100 | 0 |
single | shallow | shallow | sol. | 18 | 23.2 (15) | 1.1 (0.2) | — | — | 72 | 0 |
single | shallow | shallow | ass. | 2 | 20.5 (13.4) | 1 | — | — | 100 | 0 |
single | deep | descent | sol. | 39 | 28.9 (11.4) | 0.2 (0.5) | — | — | 15.0 | 0 |
single | deep | descent | ass. | 5 | 38.6 (25.5) | 0 | — | — | 0 | 0 |
single | deep | bottom | sol. | 34 | 19.2 (10.9) | 0.7 (1) | — | — | 56 | 0 |
single | deep | bottom | ass. | 0 | — | — | — | — | — | — |
single | deep | ascent | sol. | 40 | 28.6 (13.5) | 1 (1) | — | — | 63.0 | 0 |
single | deep | ascent | ass. | 4 | 35.3 (5) | 1 (0.8) | — | — | 75 | 0 |
school | all | complete | sol. | 29 | 50.4 (33.4) | 3.6 (2.9) | 0.6 (0.8) | 0.04 (0.2) | 93 | 48 |
school | all | complete | ass. | 19 | 24.5 (18.7) | 3.3 (3.2) | 1.1 (1.4) | 0.3 (0.5) | 89 | 58 |
school | shallow | shallow | sol. | 13 | 13.6 (9.3) | 1.3 (2.4) | 0.5 (0.5) | 0.1 (0.3) | 92 | 23 |
school | shallow | shallow | ass. | 11 | 14.2 (16.4) | 0.8 (1.5) | 0.9 (0.7) | 0.4 (0.5) | 82 | 46 |
school | deep | descent | sol. | 23 | 24.7 (11) | 0.4 (0.9) | 0.04 (0.2) | 0 | 22 | 0 |
school | deep | descent | ass. | 2 | 21.5 (5) | 3.5 (5) | 0 | 0 | 100 | 0 |
school | deep | bottom | sol. | 15 | 16.3 (16.4) | 0.6 (1.6) | 0.1 (0.3) | 0 | 53 | 0 |
school | deep | bottom | ass. | 2 | 17.5 (12) | 4.5 (2.1) | 0.5 (0.7) | 0 | 100 | 0 |
school | deep | ascent | sol. | 20 | 29 (10.8) | 3.5 (2.6) | 0.5 (0.8) | 0 | 90 | 50 |
school | deep | ascent | ass. | 5 | 42.4 (16.7) | 7.2 (1.3) | 1.8 (2.5) | 0.2 (0.4) | 100 | 100 |