European earwig phenology and effect of understorey management on population estimation

Abstract

European earwigs (Forficula auricularia L) were sampled in a Canterbury apple orchard over two growing seasons using shelter traps comprised of corrugated cardboard rolls Adult activity peaked during December and January in both seasons while activity of nymphs peaked two weeks earlier Earwig counts were consistently higher in a block receiving herbicide treatments compared with an adjacent block receiving pea straw mulch Competition between the sampling unit and the surrounding peastraw habitat probably explains this effect Factors affecting the sampling method used are discussed and the need for an alternative sampling system that better reflects absolute abundance is concluded

Frass sampling and baiting indicate European earwig (Forficula auricularia) foraging in orchards

“…This experiment compared the season-long sampling efficacy of cardboard rolls and diet tubes (earwig abundance and frass) with predation rates on apple trees of seeded leafroller (Lep., Tortricidae) egg batches. Five corrugated cardboard rolls (100 · 850 mm; Burnip et al 2002) were placed on the south side at the base of apple trees in the pea straw ground cover treatment, and checked for earwig numbers weekly from 1 October 2002 to 22 April 2003. Five diet tubes were placed in the canopy of each of the same five trees in the same blocks as above and then checked for earwigs and frass over the same time period.…”

“…The potential economic importance of earwigs in New Zealand apple orchards derives from the development of integrated fruit production (Walker et al 2001;Suckling et al 2003), which in part aims to maximize the benefit from natural enemies for pest management. The widespread distribution and abundance of earwigs raises the consideration of whether they could be deliberately managed in orchards (Burnip et al 2002). Earwigs have several biological attributes contributing to their potential for inundative or augmentative biological control.…”

Optimizing biocontrol using phenological day degree models: the European earwig in pipfruit orchards

“…Their population densities can greatly vary within and between growing seasons and locations (Moerkens et al , 2009). In the past, attempts have been made to increase their abundance in the understorey (Burnip et al , 2002; Suckling et al , 2006).…”

Potential of the European earwig (Forficula auricularia) as a biocontrol agent of the soft and stone fruit pest Drosophila suzukii

“…Boxes both with and without earwigs were placed in an incubator set to a June cycle (11-21 ∘ C temperature cycle, 16:8 h light/dark cycle, peak temperature at 13:00, lowest at 05:00) on 10 March 2017 for 7 days. A June cycle was selected as early summer is the optimal season for F. auricularia activity, with daytime temperatures between 20 and 25 ∘ C. 32,38,39 Upon removal, the same method of sugar extraction for four of the eight cherries was executed as previously outlined. The remaining four cherries were placed in controlled chambers in the insectary at 23 ∘ C in a 12:12 h light/dark cycle.…”

“…F. auricularia are known to be most active in temperatures between 20 and 24 ∘ C, akin to those of early summer, with large fluctuations in temperature and high maximum temperatures discouraging activity. 32,38,39 Thus, it seems possible that predation may have been higher in the insectary trials as temperatures were optimal for earwig activity. Additionally, optimum temperatures for oviposition are 19-25 ∘ C and D. suzukii is also likely to exhibit behavioural rhythms in locomotor activity and reproductive success that are sensitive to environmental temperature.…”