Dispersal of a carabid beetle in farmland is driven by habitat‐specific motility and preference at habitat interfaces

Abstract

Carabid beetles are common predators of pest insects and weed seeds in agricultural systems. Understanding their dispersal across farmland is important for designing farms and landscapes that support pest and weed biological control. Little is known, however, about the effect of farmland habitat discontinuities on dispersal behaviour and the resulting redistribution of these beetles. We released 1,985 well‐fed and 1,680 food‐deprived individuals of the predatory carabid beetle Pterostichus melanarius (Illiger) (Coleoptera: Carabidae) on a farm in Wageningen, The Netherlands. We recaptured 23.6% of those beetles over a period of 23 days in 2010. The farmland comprised agricultural fields with various crop species and tillage, separated by strips of perennial vegetation. We developed discrete Fokker‐Planck diffusion models to describe dispersal based on motility (m2 day−1) and preferential behaviour at habitat interfaces. We used model selection and Akaike’s information criterion to determine whether movement patterns were driven by variation in motility between habitats, preferential behaviour at habitat interfaces, or both. Model selection revealed differences in motility among habitats and gave strong support for preferential behaviour at habitat interfaces. Behaviour at interfaces between crop and perennial vegetation was asymmetric, with beetles preferentially moving towards the crop. Furthermore, beetles had lower motility in perennial strips than in arable fields. Also between arable habitats movement was asymmetric, with beetles preferentially moving towards the habitat in which motility was lowest. Neither crop type nor tillage explained differences in motility between crop habitats. Recapture data representing dispersal patterns of beetles were best described by a model that accounted for differences in motility between farmland habitats and preferential behaviour at habitat interfaces. Motility in farmland and behaviour at interfaces can also be estimated for other organisms and farmland habitats to support design of farmland conducive to natural pest suppression. Landscape design for early recruitment of carabids into arable fields should take into account the quantity and quality of resource habitats in the landscape, their proximity to crop fields, movement rates, and the possibility of movement responses at interfaces between landscape elements.

Fauna and Species Diversity of Ground Beetles (Coleoptera, Carabidae) in Meadows

“…Such ecotones can reduce migration, change the daily and seasonal movements of insects. An increase in the species diversity of insects adjacent to the biotope forest is the most likely result [41][42][43]. This is exactly what was obtained in our conditions.…”

Towards diversified industrial cropping systems?

“…Only the Pterostichus ground beetle was found to be more abundant in the REF system. Although contradictory to Thomas et al (2006) who found Pterostichus to prefer less dense crop stands, our finding is in line with Allema et al (2019) who showed that Pterostichus preferentially occupy large-scale cereal monocultures.…”

“…For example, for NEs we looked only at abundance and not at community composition at the species level. In doing so we could have missed potential treatment effects, as it has been shown for instance that certain ground beetle species prefer particular crops and crop arrangements over others (Allema et al 2015;Allema et al 2019). With both NEs and weeds, species richness is of interest from the perspective of biodiversity preservation, but species composition also matters in regard to AES delivery when the presence of certain species or functional groups may be more predictive of associated effects (Bàrberi et al 2018;Dassou and Tixier 2016).…”

Effect of Conservation Agriculture on Aphid Biocontrol by Generalist (Carabid Beetle) and Specialist (Parasitoids Wasp) Natural Enemy Communities in Winter Wheat

“…However, in some cases higher abundances were found in conventional systems (Baguette and Hance, 1997;Hatten et al, 2007;Menalled et al, 2007), but this was usually due to a single dominant species that was either indifferent to disturbance or resilient to it thanks to good colonization capabilities (Baguette and Hance, 1997;Hatten et al, 2007). Allema et al (2019) also hypothesized that in disturbed open habitat, such as conventional fields, carabids exhibit a more intense foraging activity than in complex habitat, resulting in increased trapping efficacy rather than increased abundance.…”