Abstract
Oligota kashmirica benefica NAOMI is one of the most important natural enemies of the citrus red spider mite Panonychus citri (MCGREGOR) in citrus orchards in Japan. To examine the migration of this predator between unsprayed Satsuma mandarin groves and Japanese cedar windbreaks nearby the orchards, we carried out a field investigation using a beating method for collecting the spider mites and their natural enemies in 1995. The population trend of P. citri in the groves showed a pattern with one peak in April. O. kashmirica benefca predominated among predatory insects including another staphylinid beetle O. yasumatsui KISTNER, and the population trend of the predator was closely synchronized with that of P. citri. Although the population trend of the cryptomeria spider mite Oligonychus hondoensis (EHARA) found in Japanese cedar windbreaks showed a pattern with two peaks in June and October, O. kashmirica benefica was observed only from October to December. These results suggest that O. kashmirica benefica individuals in the citrus orchards use windbreaks such as Japanese cedar infested by the spider mites for maintaining their population.
