DOI: 10.5061/dryad.34tmpg4xh
title: Edge effects and pitfall trap design influence spider diversity and assemblages in canola agroecosystems on the Canadian Prairies

description: Spiders (Araneae) are generalist predators in agroecosystems and may
 contribute to biological control in canola (Brassica napus L. and B. rapa
 L.). However, their diversity and community structure remain understudied
 in the Canadian Prairies. To address this knowledge gap, we surveyed
 spider assemblages in the Aspen Parkland region of Alberta, Canada, using
 pitfall traps placed at field edges and interiors during the 2021 and 2022
 growing seasons. In 2023, we tested pitfall trap modifications to
 improve spider retention, evaluating: 1) trap diameter, 2) preservative
 substrate (glass beads vs. propylene glycol), and 3)
 polytetrafluoroethylene (PTFE; Fluon, a non-stick fluoropolymer) coated
 trap interiors (to reduce friction and prevent escape). This was tested
 across canola habitats adjacent to grass- or tree-dominated non-crop
 habitat edges. The uploaded dataset contains all spider identifications
 from 2021 to 2023.
description: # Edge effects and pitfall trap design influence spider diversity and
 assemblages in canola agroecosystems on the Canadian Prairies Dataset DOI:
 [10.5061/dryad.34tmpg4xh](10.5061/dryad.34tmpg4xh) ## Description of the
 data and file structure **Spider diversity and composition in canola.** To
 assess spider diversity and activity density in canola fields, pitfall
 trapping was conducted between June and August 2021 (n = 5 sites) and 2022
 (n = 5 sites). At each site, two parallel 100 m transects were
 established: one at a field edge, adjacent to semi-natural non-crop
 habitat (0.5 m from the edge), and another one at the field interior (100
 m into the field). **Pitfall trap design comparisons.** To optimize the
 pitfall trap design to improve spider retention, an experiment was
 conducted in 2023. The experiment evaluated the impact of pitfall trap
 diameter (small, medium, large), preservation method (i.e., killing agent
 (propylene glycol) vs. live trapping (glass beads)), interior trap wall
 non-stick coating (polytetrafluoroethylene , PTFE), and collection period
 length (7 days and 24-hours) on spider sampling. ### Files and variables
 **Spiders_2021-2022.xlsx** - Spider diversity and composition in canola.
 All identification data of spiders collected in canola fields in 2021 and
 2022.  | Column Header | Definition | | :--------------- |
 :------------------------------------------------------------------------
 | | Sample ID | Sample identifier (combination of fieldID, transect, and
 collection date) | | TrapID | Trap identifier (combination of fieldID,
 transect, and trap number) | | Year | Year of collection | | FieldID |
 Field identifier | | Transect | Edge (E) or Interior (I) transect  | |
 ColDat | Collection date | | Family | Family | | Genus | Genus | |
 Specific epithet | Specific epithet | | Sex | Male (M), Female (F) or
 underdetermined (NA) | | Count | Number of spiders collected | | Species
 full | Species name | **Spiders_2023.xlsx** - Pitfall trap design
 comparisons. All identification data of spiders collected near canola
 fields in 2023.  | Column Header | Definition | | :--------------- |
 :------------------------------------------------------------------------
 | | Sample ID | Sample identifier (combination of fieldID, transect, and
 collection date) | | TrapID | Trap identifier (combination of fieldID,
 transect, and trap number) | | Year | Year of collection | | Timeframe | 7
 day sampling period (7D) or 24 hours (24H) | | FieldID | Field identifier
 | | Habitat | Habitat which the traps were setup. Grass (GR) or tree (TR)
 | | Size | Trap diameter: small (S), medium (M) or large (L) | | Treatment
 | Trap treament. One of: | | 
 
 | Trap with Propylene Glycol and No Fluon (PG0) | | 
 
 | Trap with Propylene Glycol and Fluon (PGF) | | 
 
 | Dry trap without Fluon (D0) | | 
 
 | Dry trap with Fluon (DF) | | ColDat | Collection date | | Family |
 Family | | Genus | Genus | | Specific epithet | Specific epithet | | Sex |
 Male (M), Female (F) or underdetermined (NA) | | Count | Number of spiders
 collected | | Species full | Species name | 
 
 ## Code/software Microsoft Excel, Google Sheets, or an editor capable of
 viewing .xlsx files.