DOI: 10.5061/dryad.z08kprrcm
title: Data from: Ant community composition and functional traits in newly established grasslands within agricultural landscapes

description: Ongoing intensification and fragmentation of European agricultural
 landscapes dramatically reduce biodiversity and associated functions.
 Enhancing perennial non-crop areas holds great potential to support
 ecosystem services such as ant mediated pest control. To study the
 potential of newly established grassland strips to enhance ant diversity
 and associated functions, we used hand collection data and predation
 experiments to investigate differences in (a) ant community composition
 (b) biocontrol related functional traits, and (c) natural pest control
 across habitats in cereal fields, old grasslands, and new grassland
 transects of three years age.  Whilst all data
 regarding biocontrol related functional traits of ant species (b)
 are available within the publication and its supporting information files,
 we provide here our raw data of ant species activity and
 diversity surveys (a) and further the results of sticky card experiments
 as a proxy for biocontrol potential (c).
description: a)
 Ant activity and diversity were recorded using hand collections of worker
 ants with fine tweezers. Hand collection is considered the most efficient
 method for sampling ants (Gotelli et al. 2011), and is not biased in
 favour of behaviourally dominant species that monopolize food-resources
 (Andersen, 1997), which may occur when using bait traps. A total of three
 consecutive survey runs on each of the 90 sampling plots was performed,
 with 14 to 21 days between each run. On each sampling plot, two 1x1 m
 sized quadrants around the centre were searched for foraging worker ants
 for four minutes each per run. Worker ants active around nests were also
 sampled and the total aboveground nest activity (number of observed ants
 in steps of 10 individuals) estimated. Prior to the hand sampling, local
 vegetation cover (0-100 % of bare soil covered) was estimated visually in
 a radius of 2 m around the plot centre. All collected individuals were
 preserved in 70 % ethanol and identified to species level according to
 Seifert (2018), using a stereo-microscope at 10-fold
 magnification. c)
 Biocontrol potential was measured using sticky-card experiments with adult
 Drosophila melanogaster (Meigen) flies as baits. Predation on fruit flies
 is well suited as a general proxy for pest control, because fruit flies
 are available in large numbers with a body size that allows all kind of
 different predators to prey on them (Lys, 1995). Further, fruit flies are
 easily re-detectable which allows data recording. Even though highly
 specialized and/or parasitic predator species might not be attracted when
 using fruit flies as baits, the results offer general interpretation, as
 pest control in farmlands is foremost provided by common generalist
 predators (Symondson, Sunderland, & Greenstone, 2002). We recorded
 each sampling plot with four consecutive survey runs (total of 720
 observations/cardboards). On each sticky-card, thirty flies were glued to
 the upper side of a 6x8 cm cardboard, which had a plastic underlay (to
 protect the card from soil moisture), and fixed to the ground with a long
 nail. Flies were glued to the cardboard with well-diluted fish-glue
 enabling ground-dwelling predatory arthropods to remove the prey which
 guarantees successful predation (Lys, 1995). Each cardboard was covered by
 an enclosure with an appropriate mesh size (1x1 cm) to prevent access of
 rodents and birds and allow recording of arthropod predation on fruit
 flies (Hulme, 1996). Two cardboards were placed on each sampling plot per
 survey and exposed to predatory arthropods for 2-3 hours. Afterwards,
 predation rates (number of removed flies) and the estimated vegetation
 cover of the sampling plots (0-100 % of surface covered) were recorded
 directly in the field. We observed sticky cards for 10 minutes after
 exposure to the field, as well as during collection of the cards, to
 record (whenever possible) the identity of arthropod predators accessing
 the baits.