DOI: 10.5061/dryad.70rxwdbw9
title: Data from: Size matters: when resource accessibility by ecosystem engineering elicits wood-boring beetle demographic responses

description: This data was used to investigate how the age and size of beaver
 disturbances act as predictors for primary wood-boring beetle abundance
 and species richness around beaver-altered habitat patches. To do so, we
 sampled beetles around 16 beaver-disturbed and unaltered watercourses
 within the Kouchibouguac National Park (Canada) and modeled beetle
 demographical responses to site conditions and their physical
 characteristics, distance from the watercourse, deadwood biomass, and the
 geographical location of the sites.
description: The study was conducted in Kouchibouguac National Park (lat. 46°
 48’ N, long. 64° 54’ W), a 238-km<sup>2</sup> federal park
 located in eastern New Brunswick, Canada. We used 16 sites previously
 identified as beaver-engineered (BEA), where watercourses encompassed
 beaver activity material (i.e., beaver dam, pond and/or meadow). We
 determined the age (in years; 12 to 44 years old) and the perimeter (in m;
 135 to 889 m) of the disturbed area through aerial photography. We paired
 BEA sites with control sites (CON), which each included a watercourse
 without any sign of beaver activity within 100-m radius from the CON
 periphery. Hereafter, we will use the term “site condition” as a general
 concept encompassing both BEA and CON. At each site, we ran a 50-m
 transect oriented perpendicularly to the watercourse. For BEA, each
 transect began at the limit of the flooded area. The transects for meadows
 began at the end of habitat patches linked to ancient flooding. Transects in BEA and
 CON intersected the same
 type of habitats since we used beaver ponds with a sharp perturbation
 edge, preventing any bias of wetlands (not directly linked to beaver
 activity) buffering the beaver-modified habitat.
 Flight-intercept traps (FIT) were
 installed at 5, 20, and 50 m along the transects. Each trap was composed
 of two perpendicularly inserted 30.5 x 61 cm acrylic sheets under which a
 styrene funnel was attached. A plastic cup was placed at the bottom of
 every funnel and contained a mixture of 70% ethanol and a drop of
 dishwashing soap. Two clothespins were pinned on the base of an acrylic
 sheet to stabilize the FIT and a round styrene cover was placed over the
 FIT to prevent debris and rain from accumulating in the collecting cup.
 Each trap was suspended at 1.6 m above ground, from the center of the
 acrylic sheets, on a rope attached to two trees that were less than
 4 m apart. Placing the traps between the trees rather than
 against the trunk of a given tree species allowed for the sampling of all
 saproxylic beetles and not only that of the beetles attracted to a given
 host species. From the beginning of June to the end of
 August in 2015 and 2016, traps were emptied bimonthly to recover
 wood-boring beetles. We only selected beetle taxa known to actively bore
 into fresh dead wood material (i.e., Ptinidae, Lymexylidae, Cerambycidae
 and Buprestidae families, and Scolytinae, Conoderinae and Cossoninae
 subfamilies). Beetles were classified in two trophic categories, being
 coniferous borers or deciduous borers.
description: The dataset includes the pooled volume in our sampling plots of
 all woody debris (snags and logs) of the same essence (coniferous or
 deciduous) for fresh debris (class 1–2) and old debris (class 3-4-5), our
 ordinal numeric variables (i.e., distance from the watercourse, perimeter
 of the disturbance, disturbance age, site coordinates), and five dependent
 variables (i.e., <i>Anisandrus sayi</i> abundance,
 coniferous-borer abundance/richness, deciduous-borer abundance/richness).
 <i>Anisandrus sayi</i> abundance was analyzed separately from
 other deciduous borers because of its sheer abundance compared to other
 species in this study and other work carried out in New Brunswick,
 Canada.