Changes in habitat selection patterns of the gray partridgePerdix perdixin relation to agricultural landscape dynamics over the past two decades

Abstract

Changes in agricultural practices have reshaped agricultural landscapes and triggered a drastic decline in spatial and temporal heterogeneity leading to changes in habitat quality and food resources for birds. However, the precise relationships between landscape changes, spatial and temporal heterogeneity, and habitat preferences in response to those changes remain poorly known. We investigated patterns of habitat selection and causes for changes over the years 1997–2017 for the gray partridge Perdix perdix , an iconic farmland species which has experienced a severe decline since the 1950s. Using a long‐term (1997–2017) dataset collected over 435 km 2 , we modeled relationships between annual land‐cover maps and partridge sightings over 17 5‐year moving windows, assessing the effects of landscape metrics, the strength of the relationships, and the dynamics of habitat suitability. We detected a shift in gray partridge habitat preferences over time, toward more risky habitats. Avoidance of predator reservoirs (woodlands and buildings) has weakened, and selection of human infrastructure, such as roads and tracks, has increased. Since 1997, the mean size of suitable patches has also decreased by about 26%. We have interpreted these changes in habitat selection as being the result of decreasing habitat quality and the increasing prevalence of captive‐reared birds, currently released in their thousands in the study site. Synthesis and applications . The gray partridge has not adjusted well to changes in farming practices, and the low, still decreasing, population density suggests that it is not sustainable, despite local initiatives and the investment in captive‐bird releases. We emphasize that efforts must be redirected toward habitat improvement to restore the density of refuge cover, insects, and seeds in the landscape, hunting management to ensure self‐sustainable populations and massive releases of high‐quality birds. Only integrated local management, involving hunters, farmers, gamekeepers, and scientists can ensure the recovery of this species.

Impact of land cover and landfills on the breeding effect and nest occupancy of the white stork in Poland

“…Nest-site and habitat selection in general have been shown to be affected by both land use and climate 64 – 69 ; thus changes in farming management were particularly severe in the case of farmland bird species, many of which declined due to loss of habitats 70 – 73 . As opposed to land use, weather conditions are rarely considered in habitat selection studies, but are in fact drivers of seasonal variation in selecting habitat.…”

Rural landscape dynamics over time and its consequences for habitat preference patterns of the grey partridge Perdix perdix

“…Accordingly, degradation of habitat and food resources have been resulting in a severe reduction in biodiversity [ 1 , 3 , 5 – 7 ] and by more than 50% of the EU farmland bird indicator since 1980 [ 7 – 9 ]. Although agricultural land is covering about 40% of the terrestrial earth surface, so far only single studies have been assessing land-cover changes over time (see in [ 10 ]) or related them to changes in habitat choice of farmland birds (but see [ 11 , 12 ]).…”

“…Interestingly, in Europe, in large-scale intensive farmland the area of infrastructure such as roads as well as hedgerows and woodlands have mainly remained stable over the years [ 12 ], while crops have changed annually due to crop rotation [ 13 ]. In contrast, in less intensive agricultural areas e.g., in the Alpine regions, indicating less quality soil meadows or open habitats (e.g., set asides) change to higher succession stages (e.g., bush land or forests) because farmers lose financial revenues for the sustenance of such structures.…”

“…Most of the above-mentioned European studies focused on habitat choice in birds in intensive farmlands where infrastructure does not seem to change [ 12 ]. As a result, there is little evidence on the association of habitat preferences with the change of landscape heterogeneity over time and space caused not only by augmenting crop area size but also by increasing building and infrastructure.…”

“…In most of the studies on habitat preference in grey partridge, the effects of landscape features have been studied independently from each other. Consequently, there is still little known on the relative contributions of single landscape parameters for the partridge’s habitat preference in farmland landscape in space and time (but see [ 12 , 24 , 40 ]). Even less is known about potential changes in patterns of habitat preference over time in highly dynamic agricultural landscapes, particularly close to cities.…”