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.
ContextThe underlying mechanisms determining the scale at which species interact with their environment are still poorly known.Objective We investigated the spatial extent at which landscape structure affects the occurrence of four species of terrestrial mammal herbivores in the Brazilian savannas and tested whether those scales could be explained by species ecological traits and habitat definition.Methods Using maps of forest cover, camera trapping and occupancy modelling, we determined the relations between three landscape metrics (percentage of forest cover, patch density and edge density) and the occurrence of four species. To determine the optimal scale of effect for each species, we computed landscape metrics at different spatial extents (from 0.5 to 10 km radius) from camera trap locations and for three forest maps, considering different definitions of what is a "forest" (minimum of tree cover of 25, 50 or 75% per pixel). ResultsThe occupancy models revealed scales of effect of 0.5 to 2 km, and those scales overlapped highly among species. However, the strength of the effect depends highly on how forest is defined, being stronger when forest was defined with greater tree cover, particularly for forest-dwelling species.Conclusions Besides biological traits, the way habitat is defined shapes our ability to detect scale of effects. Thus, if we want to properly identify scales of effect for multiple species, it is necessary not only to adopt a multi-scale approach, but also to use multiple definitions of habitat, considering particularities of how each species interact with their environment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.