Abundance and Seasonal Activity of Weevils (Coleoptera: Curculionidae) in a Raspberry Plantation and Adjacent Sites in Southern Quebec (Canada).

In a raspberry plantation and adjacent sites in southern Quebec, we collected weevils with unbaited pitfall traps and flight interception traps from early May througb late October in 1987-1989. We captured a total of 1592 weevils representing 65 species, including at least 21 Holarctic or introduced species in North America. In and around the raspberry plantation, the commonest species collected by the two methods were the short-nosed weevils of subfamilies Otiorhynchinae and Thylacitinae, mainly generalist species with root-feeding larvae. Ceutorhynchinae and Tychiinae species were also abundant in flight traps near the raspberry plantation, whereas Hylobius congener was the most abundant weevil active at the ground surface in an adjacent pine woods. Sciaphilus asperatus and Otiorhynchus ovatus, two introduced wing­ less weevils, were the most abundant species caught with pitfall traps in raspberry rows; the increase of their abundance in the young plantation was probably associated with the increase of raspberry root mass and canopy during the three study years. The weevil fauna at a woods-field boundary was quite variable in the relative abundance of species active in open sites or in wooded sites. We studied the seasonal activity of H. congener, O. ovatus, S. asperatus, Sitona lepidus, Trachyphloeus bifoveolatus, and nine other minor weevil species.