Birds

Rat control using anticoagulant rodenticides on livestock farms is a widely applied practice worldwide. Birds can be exposed to rodenticides through direct ingestion or secondary poisoning, resulting in mortality or sublethal health effects. While impacts on raptors and owls are well documented, potential effects on songbird communities in farmland settings have received limited empirical investigation. To address this gap, avifaunal surveys were conducted on 12 livestock farms in the Münsterland, Germany, during 2021–2022, comparing farms with and without rodenticide application to assess impacts on songbird and farmland bird communities. In addition, farm structures, such as the proportions of grassed areas and buildings, were quantified using spatial analysis (linear mixed-effects model). Farm structure showed patterns in bird abundance and community composition, with the proportion of buildings and grassed area showing the most notable associations with bird abundance and ground-nesting species respectively. Rodenticide application showed possible associations with the number of individual birds. However, none of those patterns reached statistical significance, and causal mechanisms remain unclear due to the observational design. Larger-scale studies are needed to assess population-level consequences and optimize rodenticide use alongside habitat management.

The winter diet of Black Francolin (Francolinus francolinus) is poorly documented in Totali Public Game Reserve, Pakistan. We examined crop contents from 24 legally harvested birds (14 males and 10 females) collected during 2022–2024. Thirty-three identifiable food taxa were recorded, comprising 22 plant and 11 animal taxa, together with unidentified plant and animal material. Dietary composition was quantified using frequency of occurrence, numerical abundance, mass percentage, and importance value (IV%). Plant material dominated numerically, with Poaceae (IV = 57.1%) and Fabaceae (IV = 25.7%) contributing most strongly among plant families, whereas Formicidae dominated the animal component (IV = 70.8%). Dietary indices were Shannon–Wiener H’ = 2.34, Simpson’s 1-D = 0.84, Pielou’s J’ = 0.67, and standardized Levins’ niche breadth B_sta = 0.16, indicating an uneven winter diet concentrated in a limited subset of resources despite the number of taxa recorded. Body mass, crop mass, and dry food mass did not differ significantly between sexes. Body mass was positively correlated with crop mass (r = 0.61, p = 0.001) and dry food mass (r = 0.59, p = 0.002). These findings provide a site-specific description of the winter diet and a baseline for future seasonal, multi-site, and resource-availability studies.

Columbidae (pigeons and doves) are among the most abundant resident birds in agricultural landscapes and recorded as turbine fatalities, but they are rarely included in collision risk assessments. We evaluate nine years (2016–2024) of monitoring data from a wind farm in the Isthmus of Tehuantepec, Mexico, to estimate species-specific collision risk and fatalities for five species using a Bayesian Collision Risk Model (CRM). We integrated long-term visual census data, systematic carcass searches corrected for detection probability and carcass persistence, and biologically informed priors to estimate exposure rates, collision probabilities, and annual fatalities. Results revealed marked interspecific differences in collision risk that were not directly proportional to abundance. The most abundant species, White-winged Dove (Zenaida asiatica), showed high exposure but low collision probability. The opposite was found in less abundant species White-tipped Dove (Leptotila verreauxi). While overall estimated fatalities remained low, our model revealed a steady downward trend in absolute fatalities, projecting continued declines for 2025. Our findings highlight the importance of long-term monitoring and Bayesian approaches that incorporate uncertainty and species-specific traits. We provide parameterized priors that can be applied in future collision risk models and support the conclusion that wind farms may exhibit limited local mortality impacts on the studied avifauna.