DOI: 10.5061/dryad.qfttdz0w5
title: Data for: Effect of low-traffic roads on abundance of ground-nesting birds in sub-Arctic habitats

description: Roads are one of the most widespread anthropogenic structures, and their
 presence can impact biodiversity in the surrounding landscapes through
 disturbance and collision risk, particularly when traffic volumes are
 high. However, the impact of roads with low traffic volumes in open
 landscapes is much less clear. In the open landscapes of lowland Iceland,
 road traffic is still relatively low but increasing and the surrounding
 landscapes support internationally important populations of several
 breeding wader species. Here, we used transect counts, perpendicular to
 low-traffic (≤ 15,000 vehicles/day) roads across the lowlands of southern
 Iceland, to quantify variation in densities of ground-nesting birds with
 distance from roads and how far from the roads any such effects extended.
 The total abundance of birds increased significantly by 6% per 50 m
 interval from roads, and densities within 200 m of roads were ~20% lower
 than densities between 200 and 400 m from roads. Four species (Whimbrel
 (Numenius phaeopus), Golden plover (Pluvialis apricaria), Dunlin (Calidris
 alpina), and Meadow pipit (Anthus pratensis) were found in significantly
 lower densities closer to roads, while four (Black-tailed godwit (Limosa
 limosa), Redshank (Tringa totanus), Snipe (Gallinago gallinago) and
 Redwing (Turdus iliacus)) showed no change with distance to roads. Redwing
 was found in higher densities and Dunlin in lower densities surrounding
 roads with higher traffic volume. As approximately 20% of lowland Iceland
 is within 200 m of roads, the impact of roads on the overall abundance of
 ground-nesting birds could be substantial. The results show that even
 relatively low-traffic roads can have a significant impact on adjacent
 wildlife populations. Road construction along with other anthropogenic
 structures has been shown to have negative effects on bird abundance, and
 identifying areas for protection from such developments may be the most
 effective approach to reduce human impacts on the internationally
 important wildlife of lowland Iceland.
description: # Data for: Effect of low-traffic roads on abundance of ground-nesting
 birds in sub-Arctic habitats Dataset DOI:
 [10.5061/dryad.qfttdz0w5](https://doi.org/10.5061/dryad.qfttdz0w5) ##
 Description of the data and file structure Transect: Transect identity.
 Year: Year transect was counted Date: Date Timestart: Time transect count
 was started Timend: Time transect count ended Habitat: Habitat type class
 of transect SDU: Summer day traffic (average number of cars/day in
 summertime (June-september) gpsa1: Latitude gpsa2: Longitude Counter:
 Initials of the person who conducted the transect Interval: Distance
 interval from road (Interval 1: 0-50 m; Interval 2:51-100 m etc) Distance:
 Distance from road at the end of that interval. Columns M-AE have the
 names of each species counted. Each cell contains number of individuals of
 that species, seen within each interval per transect. ### Files and
 variables #### File: RoadDRYAD.csv **Description:** Excel file with the
 raw data for associated paper. ##### Variables: Transect: Transect
 identity. Year: Year transect was counted Date: Date Timestart: Time
 transect count was started Timend: Time transect cound ended Habitat:
 Habitat type class of transect SDU: Summer day traffic (average number of
 cars/day in summertime (June-september) gpsa1: Latitude gpsa2: Longitude
 Counter: Initials of the person who conducted the transect Interval:
 Distance interval from road (Interval 1: 0-50 m; Interval 2:51-100 m etc)
 Distance: Distance from road at the end of that interval. Columns M-AE
 have the names of each species counted. Each cell contains number of
 individuals of that species, seen within each interval per transect. ##
 Code/software R was used for statistical analysis and qGis for spatial
 calculations.