Invader effects in a community of cavity nesting Megachilid bees (Hymenoptera: Megachildae)

  • Published source details Barthell J.F., Gordon W.F. & Thorp R.W. (1998) Invader effects in a community of cavity nesting Megachilid bees (Hymenoptera: Megachildae). Environmental Entomology, 27, 240-247.


This study is summarised as evidence for the following.

Action Category

Exclude introduced European earwigs from nest sites

Action Link
Bee Conservation
  1. Exclude introduced European earwigs from nest sites

    Thirty drilled pine wood solitary bee nest boxes were suspended from 15 valley oak trees Quercus lobata on the Cosumnes River Preserve, near Sacramento, Caifornia, USA, in 1990 (Barthell et al. 1998). The boxes each had twelve 10 cm-deep holes, 0.65 cm in diameter. Boxes were placed in pairs. One on each tree excluded crawling earwigs Forficula auricularia using the sticky barrier Tanglefoot. The treatment substantially reduced the number of earwigs found in the boxes and allowed a greater total number of bee cells (during the peak bee nesting week, there were 134 cells in boxes with Tanglefoot, 45 cells in untreated boxes). The majority of nesting bees in this study were native species of the leafcutter bee genera Megachile and Osmia although introduced species of Megachile were also present.

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