Data for: Effect of low-traffic roads on abundance of ground-nesting birds in sub-Arctic habitats

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..., , # 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 a...,