Phenology of carpophilus beetle populations (Coleoptera: Nitidulidae, Carpophilus spp.) in a fruit dump in northern Victoria

Carpophilus spp. are important pests of stone fruit in Australia. Maintenance of good orchard hygiene has been promoted as a way of reducing pressure from Carpophilus spp. In northern Victoria, Australia, it is common practice for fruit processors to dispose of waste fruit in dumps, many of which are near orchards. The importance of such dumps to Carpophilus spp. was not previously known. Seasonal variation of Carpophilus spp. in a fruit dump in Cobram, northern Victoria, was studied from September 1998 to September 2000. Three locations within the dump were randomly selected and inspected for presence of adults, larvae and pupae of Carpophilus spp. at regular intervals. Adults were used to determine species composition. Three species, C. hemipterus, C. humeralis and C. davidsoni were observed, with the former almost always dominant throughout monitoring. Carpophilus davidsoni was recorded only twice and in small numbers. The greatest number of C. hemipterus adults occurred during autumn and spring. Larval populations were high in late spring and early autumn and overwintering occurred as adults, larvae and pupae. The potential of populations of Carpophilus spp. in the fruit dump to cause damage in nearby ripening stone fruit is discussed.