DOI: 10.5061/dryad.5nk0j
title: Data from: Correlates of habitat fragmentation and northern bobwhite abundance in the Gulf Prairie Landscape Conservation Cooperative

description: The northern bobwhite Colinus virginianus has experienced range-wide
 declines over the last several decades, primarily due to habitat loss and
 habitat fragmentation. As northern bobwhite populations continue to
 decline, there is a need for studies that address the impact of habitat
 changes on population persistence at multiple spatial scales. Our goal was
 to assess changes in habitat and land use related to northern bobwhite
 declines across multiple spatial scales in Texas, Oklahoma, and Louisiana.
 We determined northern bobwhite trends for 1972-2012 using Breeding Bird
 Survey data. At the regional scale, we compared northern bobwhite
 population trends with road density (2000, 2012), human population
 (1970-2010), and land use (1974-2012). At the county and local scales, we
 compared class-level landscape metrics between counties with stable and
 declining northern bobwhite abundances using Student's t-tests.
 Northern bobwhite populations decreased from 45.95 ± 1.01 birds/route in
 1970 to 11.55 ± 0.64 birds/route in 2012. Road density and human
 population increased by 3,331.32 ± 66.28 m/km2 and 42,873 ± 8,687
 people/county, respectively. Percent pasture and rangeland was relatively
 stable, as was percent woodland. Alternatively, the percentage of other
 land (houses, roads, wasteland) increased. At the county scale, Texas and
 Oklahoma counties with declining northern bobwhite populations had higher
 road densities, larger patches of pasture, smaller patches of woodland,
 and larger patches of cropland compared to stable populations. At the
 local scale, Texas and Oklahoma counties with declining northern bobwhite
 populations had less woody cover in smaller patches, and fewer but larger
 patches of herbaceous and bare ground, compared to populations with stable
 abundance. Therefore, while managers can provide woody cover and reduce
 cropland effects at the local scale to support stable quail populations,
 the large-scale drivers of northern bobwhite decline, which are human
 population growth and resulting habitat loss, will be an important aspect
 of northern bobwhite conservation and management in the future.
description: Northern bobwhite data
 (Breeding Bird Survey)File of northern
 bobwhite observations from the North American Breeding Bird Survey.
 Species_total refers to the total number of northern bobwhite observed on
 the 25-mi route. Latitude and longitude coordinates refer to the starting
 point for the route.S1_NOBO.csvClass level landscape metrics at the metapopulation persistance scaleMetapopulation persistence (8, 50, and 96 km2) scale class level landscape metrics for counties with declining and stable populations of northern bobwhite. Metrics are as follows: percent land (Pland_%), patch density (PD_#_km2), largest patch index (LPI_%), edge density (ED_m_km2), patch area (Area_km2), and Euclidean nearest neighbor patch (ENN_m). Classes included pasture/rangeland, woodland, cropland, other land, and water.S3_MetapopPersistLevel.csvClass level landscape metrics at the home range scale.Home range (0.15 km2) scale class level landscape metrics for counties with declining and stable populations of northern bobwhite. Metrics are as follows: percent land (Pland_%), patch density (PD_#_km2), largest patch index (LPI_%), edge density (ED_m_km2), patch area (Area_km2), and Euclidean nearest neighbor patch (ENN_m). Classes included wood, herbaceous, and bare ground. Herbaceous and bare ground were combined for analyses.S4_HomeRangeLevel.csv