| Abstract: | From May to July 1982 and 1983, coccinellids were sampled in habitats that differed in aphid density, insolation, and host plant type. The number of adults ofCoccinella 7-punctata (CS),C. 5-punctata (CQ),Propylea 14-punctata (PQ),Adonia variegata (AV),Adalia bipunctata (AB),A. 10-punctata (AD), andCalvia 14-guttata (CA) were recorded. AB, AV and CS preferred high, while CQ tolerated low aphid density. CQ, CS, AB and AV preferred sunny, while AD and CA tolerated shaded conditions. CS and AV preferred herbaceous plants, AD and CA large plants, particularly trees, AB showed little specialization, CQ preferred trees early in the season and sparse herbaceous plants later. PQ appeared to be a generalist with a wide tolerance of all these factors, but with a tendency to move from trees to herbaceous plants as the season progressed. Habitats with a high abundance of a species were assumed to be those with on optimum combination of the preferred conditions. There were slight differences in the breadth of habitat preferences, and a little habitat overlap between species. The tendency to aggregate was greater in AB than in other species. Annual variations in species abundance influenced the number of habitats occupied, but not the abundance in the favoured places. |
